Status Report on the Development of HFC®245fa as a

Blowing Agent

M. C. BOGDAN , D. J. WILLIAMS , P. B. LOGSDON, R. C. PARKER

AlliedSignal Inc.

ABSTRACT

December 31,1995 marked the end to the manufacture

of CFCs in the U.S. for use as blowing agents. The foam

industry has successfully converted to HCFC-141b and

other blowing agents. This, however, is not the last transition that the industry needs to make.

HCFCs have specific phaseout dates, according to the

Montreal Protocol which differ across the globe. Currently, the manufacture of HCFC-141b for use as a blowing agent in the U.S., will cease on January 1, 2003. The

identification of the next generation of blowing agents has

begun as a response to this market need.

AlliedSignal is committed to supplying a blowing agent

to meet customer needs in the foam industry. In 1994, at

the Polyurethane World Congress, AlliedSignal announced HFC-245fa (1,1,1,3,3- pentafluoropropane) as

their "third generation" blowing agent candidate to

replace HCFC-141b. HFC-245fa was selected on the basis

of the optimum combination of possessed attributes; it is

a liquid, nonflammable blowing agent with acceptable

environmental characteristics and good toxicological

properties. Testing performed to date on foams prepared

with HFC-245fa have demonstrated improved physical

properties and k-factor aging versus those made with

HCFC-141b. This paper discusses the recent work conducted by AlliedSignal in continuing the development of

HFC-245fa .

Before 1996, AlliedSignal's major research efforts have

been in defining the properties of HFC-245fa and proving

it as a feasible blowing agent. We are sensitive to the complexities of developing new foam technologies and want to

minimize any transition difficulties through customer

partnering. Because of this our focus has now shifted to

developing a database of information to assist our customers in selecting and converting to HFC-245fa.

This paper contains a discussion of the latest toxicity

and environmental data. It will focus on answering some

commonly asked customer questions in the areas of polyol solubility, premix vapor pressures, and cell gas content.

Research work is currently underway to optimize the

use of HFC-245fa in various industry applications which

focuses on improving k-factor and physical properties.

This work, along with a comparison of Total Equivalent

Warming Impact (TEWI) of various blowing agents being

considered, is also included.

INTRODUCTION

T

he production of HCFC-141b is currently scheduled to

cease as of January 1, 2003. In order to meet future

energy and environmental requirements, alternative

blowing agents to HCFCs, currently used in insulating

foam applications, will be required.

Although there are several potential options for replacement blowing agents, many applications will continue to

require .a liquid , non-flammable blowing agent designed

to produce foams with low thermal conductivity using traditional processing techniques. The most promising class

of materials to fill this need are the liquid HFCs. AlliedSignal is committed to supplying an alternative HFC

blowing agent to meet these needs.

In 1994 at the Polyurethane World Congress, AlliedSignal announced that HFC-245fa (1,1,1,3,3- pentafluoropropane) is our primary blowing agent candidate to

replace HCFC-141b. We consider HFC-245fa to be the

optimum replacement candidate for HCFC-141b since it

has similar physical properties, is non-flammable , is

acceptable environmentally and toxicologically and can

meet the performance requirements of the foam insulation market.

With the transition from HCFC-141b on the horizon,

there is much work to begin for an effective transition.

Each foam market segment has its own set of testing and

trials which must be completed before products containing a new blowing agent can be commercially sold. The

extent and time requirements vary dramatically from segment to segment. In addition, there are several phases of

toxicity testing which must be completed and government

approvals which must be obtained prior to HFC-245fa

becoming a commercial product.

AlliedSignal has presented a continuing series of

papers since 1992, updating the industry on our liquid

HFC blowing agent development program. This paper

provides the most recent information on the physical

properties and toxicology of HFC-245fa. With the stronger

push to utilize energy efficient appliances, reduce energy

utilization in current structures and as well as pressure to

create new structures which are more "environmentally

friendly", we have included a discussion and application of

Total Equivalent Warming Impact or TEWI on refrigerator trials performed to date. Finally, we have included

information relating to the manufacture of foam with

POLYURETHANES EXPO '96

EE-RM-93-801 COMMENT 269

Status Report on the Deve.lopment of HFC-245fa as a 

Blowing Agent 

M. C. BOGDAN, D. J. WILLIAMS, P. B. LOGSDON, R. C. PARKER 

AlliedSignal Inc. 

ABSTRACT 

December 31,1995 marked the end tothe manufacture 

of CFCs in the U.S. for use as blowing agents. The foam 

industry has successfully converted to HCFC-141b and 

other blowing agents. This, however, is not the last transition that the industry needs to make. 

HCFCs have specific phaseout dates, according to the 

Montreal Protocol which differ across the globe. Currently, the manufacture of HCFC-141b for use as a blowing agent in the U.S., will cease on January 1, 2003. The 

identification ofthe next generation of blowing agents has 

begun as a response to this market need. 

AlliedSignal is committed to supplying a blowing agent 

to meet customer needs in the foam industry. In 1994, at 

the Polyurethane World Congress, AlliedSignal announced HFC-245fa (1,1,1,3,3- pentafluoropropane) as 

their "third generation" blowing agent candidate to 

replace HCFC-141b. HFC-245fa was selected on the basis 

of the optimum combination of possessed attributes; it is 

a liquid, nonflammable blowing agent with acceptable 

environmental characteristics and good toxicological 

properties. Testing performed to date on foams prepared 

with HFC-245fa have demonstrated improved physical 

properties and k-factor aging versus those made with 

HCFC-141b. This paper discusses the recent work conducted by AlliedSignal in continuing the development of 

HFC-245fa. 

Before 1996, AlliedSignal's major research efforts have 

been in defining the properties of HFC-245fa and proving 

it as a feasible blowing agent. We are sensitive to the complexities of developing new foam technologies and want to 

minimize any transition difficulties through customer 

partnering. Because of this our focus has now shifted to 

developing a database of information to assist our customers in selecting and converting to HFC-245fa. 

This paper contains a discussion of the latest toxicity 

and environmental data. It will focus on answering some 

commonly asked customer questions in the areas of poly01 solubility, premix vapor pressures, and cell gas content. 

Research work is currently underway to optimize the 

use of HFC-245fa in various industry applications which 

focuses on improving k-factor and physical properties. 

This work, along with a comparison of Total Equivalent 

Warming Impact (TEWI) of various blowing agents being 

considered, is also included. 

INTRODUCTION 

The production of HCFC-141b is currently scheduled to 

cease as of January 1, 2003. In order to meet future 

energy and environmental requirements, alternative 

blowing agents to HCFCs, currently used in insulating 

foam applications, will &e required. 

Although there are several potential options for replacement blowing agents, many applications will continue to 

require.a liquid , non-flammable blowing agent designed 

to produce foams with low thermal conductivity using traditional processing techniques. The most promising class 

of materials to fill this need are the liquid HFCs. AlliedSignal is committed to supplying an alternative HFC 

blowing agent to meet these needs. 

In 1994 at the Polyurethane World Congress, AlliedSignal announced that HFC-245fa (1,1,1,3,3- pentafluoropropane) is our primary blowing agent candidate to 

replace HCFC-141b. We consider HFC-245fa to be the 

optimum replacement candidate for HCFC-141b since it 

has similar physical properties, is non-flammable , is 

acceptable environmentally and toxicologically and can 

meet the performance requirements of the foam insulation market. 

With the transition from HCFC-141b on the horizon, 

there is much work to begin for an effective transition. 

Each foam market segment has its own set of testing and 

trials which must be completed before products containing a new blowing agent can be commercially sold. The 

extent and time requirements vary dramatically from segment to segment. In addition, there are several phases of 

toxicity testing which must be completed and government 

approvals which must be obtained prior to HFC-245fa 

becoming a commercial product. 

AlliedSignal has presented a continuing series of 

papers since 1992, updating the industry on our liquid 

HFC blowing agent development program. This paper 

provides the most recent information on the physical 

properties and toxicology ofHFC-245fa. With the stronger 

push to utilize energy efficient appliances, reduce energy 

utilization in current structures and as well as pressure to 

create new structures which are more "environmentally 

friendly", we have included a discussion and application of 

Total Equivalent Warming Impact or TEW! on refrigerator trials performed to date. Finally, we have included 

information relating to the manufacture of foam with 

POLYURETHANES Expo '96 1 
Table 1 . Blowing agent physical properties

50

Molecular Weight 134.0 137.4 116.9 70.0 72.0

Boiling point °F 59.5 74.8 89.7 120.7 96.8

Liquid density, g/cc @68°F 1.32 1.49 124 0.75 0.63

Vapor Pressure, psia @68°F 17.8 12.8 10.0 4.9 8.3

Vapor Thermal Conductivity,

BTU in/hrlt°oF @ 111°F 0.097 0.064 0.084

BTU in/hr ftl°F @ 77°F 0.061 0.072 0.083 0.104

Flame Limits. volume % None' None' 7.6 - 17.7° 1.4 - 9.4° 1.3 - 8.'

Flash Point. °F None None None -35 -40

' ASTM E681 , amfaen• 10008068 maidf ,gfNan aye„

` Tes method not ap°0Md

Table 2. Blowing agent flammability properties

HFC-245fa CFC-11 HCFC-141b Cyclopentane n-Pentane

Flash Point, F

Tag Closed Cup None None None -35' -40'

(ASTM D56.67)

Setaflash Closed Tester

(ASTM 03828.67)

None None None

Tag Open Cup

(ASTM 0310.86)

None None - None

Vapor Flame Limits, Vol % None None 7.6-17.7° 1.4-9.4' 1 -3-8.0'

(ASTM E661-85)

Minimum Ignition Energy , m) N/A N/A 18,000 0.2-0.3

Heat of Combustion , kcat/mol 244 220 786 839

Test method not Spectiled

° Amb,ent condi9ons, match ignm«,

Table 3. Blowing agent environmental properties

HFC-245fa CFC-11 HCFC-141b HFC-134a C ntane n-Pentane

Ozone Depletion Potential 0 1 ' 0.11 0 0 0

Atmospheric Lifetime , years 8.4 50 9,4 14 Few Da

Global Warming P^entia

100 yr time h000iO1 (CO, . tl 820 4000 630 1300 3 3

VOC Status No No No No Yes Yes

A9 Osfa wept HFC-245i, MW from 'Eneegy and Dlopol Wamvrp Its of lon.otKey iw Next GO{eratan

CFCend HCFC NmmaSvm 1994

° Ndi wmiy b be mrttgerad a VOC

d3'

HFC-245ta CFC-11 HCFC- 141b Cyclopentane n-Pentane

60 iW

T eiPeel 9ra, 'F

-FHFC.2451, -e--HCFC-laud --f-CFC. 11 - M- C,cb°ema°e

110 1zd

Figure 1. Vapor pressures of some foam blowing agents

12C

HFC-245fa: Solubility, vapor pressure, a discussion of the

effect of surfactants on foam properties, cell gas content,

foam aging and k-factor vs. mean temperature. The paper

concludes with a discussion ofAlliedSignal's plans for continuing development and commercialization of HFC245fa.

PHYSICAL PROPERTIES

The physical properties of HFC-245fa are shown in

Table 1. CFC-11, HCFC-141b, n-pentane and cyclopentane are included for comparative purposes. The molecular weight of HFC-245fa is approximately the same as

that of CFC-11, therefore use levels in foams are about

equal to those used with CFC-11 to achieve a given density. The boiling point of HFC-245fa is lower than those of

the other blowing agents listed. This lower boiling point,

and therefore higher vapor pressure at any given temperature, can provide significant improvement in certain

foam properties, particularly at lower temperatures. The

vapor pressure of HFC-245fa and other foam blowing

agents as a function of temperature are shown in Figure

1. The higher vapor pressure of HFC-245fa impacts the

processing and storage of premixes. The lower boiling

point and higher vapor pressure of HFC-245fa have contributed to stronger foams with better k-factors over a

range of temperatures. These issues are discussed in the

section in the report entitled k-Factor vs. Mean Temperature and Time.

FIANEVIABILITY CHARACTERISTICS

The ability of HFC-245fa to be used in existing foam

processing equipment with minimum modifications is

important. Currently, most rigid foam processing equipment is designed to handle either non-flammable or moderately flammable liquid blowing agents. HFC-245fa is

considered "non-flammable" and has no flame limits. The

flammability characteristics of HFC-245fa are given in

Table 2. the flammabrlity properties of CFC-11, HCFC141b, cyclopentane, and n-pentane are included for comparison. Based on this test data, we believe HFC-245fa

can be used safely on all existing foam processing equipment. In fact, this material has successfully been used in

low pressure, high pressure and spray equipment. It has

also been successfully processed into refrigerator cabinets. The details will be discussed later in this paper.

ENVIRONMENTAL PROPERTIES

HFC-245fa is a non ozone depleting chemical. The environmental properties of HFC-245fa are given in Table 3.

Also included in the table are the data for HCFC-141b,

CFC-11, cyclopentane and n-pentane. The atmospheric

lifetimes of these blowing agent molecules is a key factor

in the determination of these environmental properties.

The Global Warming Potential (GWP) of HFC-245fa is relatively low compared to CFC products and other commercially available products today, such as HFC-134a, which

leads us to believe that the GWP of HFC-245fa will be

environmentally acceptable . A recent reduction of the

GWP of HFC-245fa has occurred due to a change in the

atmospheric lifetime of methyl chloroform. Because of its

atmospheric lifetime an application to exempt HFC-245fa

from being considered a VOC has been filed and we anticipate this exemption will be granted shortly.

The assessment of GWP should not only be limited to

the direct contribution of the blowing agent such as HFC245fa, but also the assessment of the indirect contribution

of the carbon dioxide emissions resulting from the energy

required to operate a system over its normal life. This

analysis is referred to as TEWI or "total equivalent warming impact".

In spring of 1995 , The American Home Appliance Manufacturers (ARAM) conducted a trial with HFC-245fa.

The formulations used to produce these refrigerator cabinets were unoptimized. Refrigerators manufactured with

HCFC- 141b were used as a control. The cabinets were

assembled and a DOE Cabinet Energy test and a Reverse

2 I Bogdan, Williams, Logsdon, Parker

EE-RM-93-801 COMMENT 269

Table 1. Blowing agent physical properties 

,,~ HFC·245ta CFC·ll HCFC·141b Cyclopentane n·Pentane 

Molecular Weight 134.0 137.4 116.9 70.0 72.0 

Boiling POint of 59.5 74.8 89.7 120.7 96.8 

LIquId density, glee 068°F 1.32 1.49 124 0.75 0.63 

Vapor Pressure, pSia @68°F 17.8 12.8 10.0 4.9 8.3 

Vapor Thermal COndUctNrty. 

BTU inlhrft'oF 0 111°F 0.097 0.064 0.084 

BTU Inlhr ft"F 0 ~F 0.061 0.072 0.063 0.104 

Flame Limits. volume %, None- Nonel 7.6·17.7' 1.4·9.4' 1.3-8.' 

Flash POint. OF None None None ·35 .40 

''''STME681,a~'COl'ldltlOM matehlQl'lltlOO cltya!' 

~ T HI method nol apeot~ 

3C 60 70 00 100 110 

~HFC·2.51. -+-HCFC-1411) """'-CFC-11 -.- C~ntane 

Figure 1. Vapor pressures of some foam blowing agents 

HFC-245fa: Solubility, vapor pressure, a discussion of the 

effect of surfactants on foam properties, cell gas content, 

foam aging and k-factor vs. mean temperature. The paper 

concludes with a discussion of Allied Signal's plans for continuing development and commercialization of HFC245fa. 

PHYSICAL PROPERTIES 

The physical properties of HFC-245fa are shown in 

Table 1. CFC-ll, HCFC-141b, n-pentane and cyclopentane are included for comparative purposes. The molecular weight of HFC-245fa is approximately the same as 

that of CFC-ll therefore use levels in foams are about 

equal to those ~sed with CFC-ll to achieve a given density. The boiling point of HFC-245fa is lower than those of 

the other blowing agents listed. This lower boiling point, 

and therefore higher vapor pressure at any given temperature, can provide significant improvement in certain 

foam properties, particularly at lower temperatures. The 

vapor pressure of HFC-245fa and other foam. blo.wing 

. agents as a function of temperature are shown m FIgure 

1. The higher vapor pressure of HFC-245fa impacts the 

processing and storage of premixes. The lower boiling 

point and higher vapor pressure of HFC-245fa have contributed to stronger foams with better k-factors over a 

range of temperatures. These issues are discussed in the 

section in the report entitled k-Factor vs. Mean Temperature and Time. 

FLAMMABILITY CHARACTERISTICS 

The ability of HFC-245fa to be used in existing foam 

processing equipment with minimum modifications is 

2 I Bogdan, Williams, Logsdon, Parker 

Table 2. Blowing agent flammability properties 

Flash POInt, SF 

HFC-245ta CFC-1 I HCFC-14 I b CycIopentane n·Pentane 

T 8g Closed Cup None None None ·35' (ASTM 05&-87) 

Setaflash Closed Tester None None None (ASTM D3828-B7) 

Tag Open Cup None None • None (ASTM 0310-B6) 

Vapor Flame Umns, Vol % None None 7.6-17.7' 1.4-9.4' (ASTM E681-85) 

Minimum Ignition Energy, mj NlA NlA 18.000 0.2·0.3 

Heat of Combusbon, kcaVmol 244 220 768 

'Test methOd not apectfted 

Il Ambtent conditions, match ignition 

Table 3. Blowing agent environmental properties 

HFC-245fa CFC-" HCFC-141b HFC-l34a i5iiiiiOOi!ntane 

Ozone Depletion Potential 0 I 0.11 0 0 

Atmosphenc Lifetime ~ars 8.4 50 9.4 I' Few08Vs 

Global Warmmg Potentia 

100 yr time horwon (COr • 11 820 4000 630 1300 3 

VOCStatus No No No No Yes 

All o.ta u:ept HFC-245fa data from Energy and GiobaI watn"III'Ig Impacts of Nof..cr'H{Jnd and Next Gerwrabon CFC and HCFC AItemIItJves· 11)9.4 

~ Not hUtyto be C:OtISIdered a vee 

·40' 

1.3-8.0' 

839 

n.-Pentane 

0 

Few Days 

3 

Yes 

important. Currently, most rigid foam processing equipment is designed to handle either non-flammable or mm:;Ierately flammable liquid blowing agents. HF~-~45fa IS 

considered "non-flammable" and has no flame lImIts. The 

flammability characteristics of HFC-245fa are given in 

Table 2. The flammabnity properties of CFC-ll, HCFC141b, cyclopentane, and n-pentane are included for comparison. Based on this test. d~ta, we believe ~C-24~fa 

can be used safely on all eXIstmg foam processmg eqUIpment. In fact, this material has successfully been used m 

low pressure, high pressure and s~ray equipment. It hB:s 

also been successfully processed mto refrigerator cabInets. The details will be discussed later in this paper. 

ENVIRONMENTAL PROPERTIES 

HFC-245fa is a non ozone depleting chemical. The environmental properties of HFC-245fa are given in Table 3. 

Also included in the table are the data for HCFC-141b, 

CFC-ll, cyclopentane and n-pentane. Th~ atmospheric 

lifetimes of these blowing agent molecules IS a key factor 

in the determination of these environmental properties. 

The Global Warming Potential (GWP) ofHFC-245fa is relatively low compared to CFC products and other comm~rcially available products today, such as HFC-134a, ~hICh 

leads us to believe that the GWP of HFC-245fa wIll be 

environmentally acceptable. A recent reduction of the 

GWP of HFC-245fa has occurred due to a change in the 

atmospheric lifetime of methyl chloroform. Because of its 

atmospheric lifetime an application to exempt HFC-24~fa 

from being considered a VOC has been filed and we antIcipate this exemption will be granted shortly . 

The assessment of GWP should not only be limited to 

the direct contribution of the blowing agent such as HFC245fa, but also the assessment of the indirect contribution 

of the carbon dioxide emissions resulting from the energy 

required to operate a system over its normal life. This 

analysis is referred to as TEWI or "total equivalent warming impact". 

In spring of 1995, The American Home Appliance Manufacturers (AHAM) conducted a trial with HFC-245fa. 

The formulations used to produce these refrigerator cabinets were unoptimized. Refrigerators manufactured with 

HCFC-141b were used as a control. The cabinets were 

assembled and a DOE Cabinet Energy test and a Reverse 

I 

I 
Table 4. Results of AHAM refrigerator trial

AHAM RE FR IGE RAT OR

TRIAL

DOE Cabinet Energy , Reverse Heat Leakage,

KwH/day BTU/hr

lowing agent HCFC-141b HFC-245fa HCFC-141b HFC-245fa

verage value 2.071 2.090 270.2 271.7

/o Increase vs 0.9 0.5

HCFC-141b

Table 5. TEW/ analysis AHAM refrigerator trial

120W

♦ Assumptions:

10Oyrtime horizion

. 20 yr. appliame lifetime

. 100% of HF -245fa xeleased

after 20 yr.

Con ibs ion fium tefrigernt

(134a) is constant

Heat Leakage test were performed on each. The results

are contained in Table 4. The refrigerators produced with

HFC-245fa had equivalent energy performance to the

ones produced with HCFC-141b even though there was a

5% higher k-factor for foams produced with HFC-245fa.

This is why actual analysis of the foam in its application

at the temperatures it will be exposed to is important.

There is an extensive discussion of k-factor vs. mean temperature included in'a latter portion of this paper.

If this energy data for the unoptimized refrigerators is

combined with the GWP for HFC-245fa, a TEWI analysis

of the refrigerators energy requirements can be calculated. The results are also displayed in Table 5. A comparison of the energy requirement for a refrigerator made

with HFC-245fa, HCFC-141b and cyclopentane are

included.

It is important to understand the assumptions which

are made in this calculation. These include : the refrigerators are operational in North America, the 100 yr. GWP

is used for each chemical to determine its direct contribution to global warming in terms of kg CO2 generated, the

life of the appliance is assumed to be 20 years, at the end

of the 20 year life all the blowing agent will be released to

the environment, and for the sake of consistency the fluorocarbon used as the compressor fluid in these examples

is HFC-134a.

The result is that the total requirements , both direct

and indirect, to operate a refrigerator produced with the

unoptimized HFC-245fa formulations has less TEWI in

its lifetime than one produced with cyclopentane. Also, it

requires approximately 8.3% less TEWI due to direct

energy requirements to operate than one produced with

cyclopentane. This is a critical concern in regions where a

consistent supply of electricity or energy production

Table 6. Summary of toxicity testing conducted on HFC-245fa to

date

TEST HFC-245fa HCFC-141b n-Pentane Isopentane Cvclo ntane

Acute Dermal LD,n> 2000 LD,,,> 2000 no LDw no LDsp no LD50

mg/kg mg/kg reported reported reported

No irritation No irritation Irritation Irritation Irritation noted

noted noted noted noted

Acute LC,a>

Inhalation 101.300 ppm

Screen- Mice

Cardiac Negative at 10.000 ppm xxx xxx Weak

Sensitization 10,000 and Threshold Sensitizer

20.000 m

Human Weak Not active up zxx xxx xxx

Lympocyte activity at to 35% v/v

30% v/v

without S9

Mouse Not active at Not active up xxx xxx xxx

Micronucleus 100,000 ppm to 36.000

PPM

Ames Assay Not Active Not Active xxx Not Active xxx

Acute (4) Hr LC,p> LCw- LCsp- xxx xxx

Inhalation- 200,000 ppm 62,000 ppm 11.260 ppm

Rats

xxx- Test results not reported

Note: No exposure level was reported for cyclopentane only a classification as a weak sensitizer

capacity is not adequate enough to meet the needs of the

population. Additional improvements in the performance

of HFC-245fa foam can,, be expected as formulation optimization is done over the next few years. Hence, the energy consumption of refrigerators prepared with HFC-245fa

should be even lower. This points out the importance of

not only considering the direct chemical effect of a substance,but also considering the total energy requirements

of the system in which it is used.

In addition to the environmental aspects, the discussion

of the long term breakdown products of CFC substitutes,

into trifluoroacetic acid (TFA) has been occurring.

Research work has recently been completed which identifies the long term breakdown products of HFC-245fa as

HF and CO2. Therefore, the use of HFC-245fa does not

lead to the formation of TFA in the environment.

TOXICOLOGICAL PROPERTIES

It is critical that the toxicity of any alternative foam

blowing agent candidate be fully defined. This data is

required not only to set industrial exposure guidelines

during storage, handling, and use of the blowing agent

during the foam manufacturing process, but is also important in risk assessment analyses of the final foam product

in its intended use and is critical to considerations in

product stewardship and responsible care.

The HCFC and HFC molecules commercialized over the

past several years, including HCFC-141b, have been

extensively tested for toxicity characteristics. HFC-245fa

is currently undergoing a similar toxicity testing protocol.

A summary of the toxicity testing conducted on HFC245fa to date is included in Table 6. Data on HCFC-141b

and hydrocarbons is also included for comparison.

The test results support that HFC-245fa has a very low

order of acute toxicity equivalent to or better than those,

reported for HCFC-141b. We are continuing our toxicity

testing and have summarized in Table 7 our anticipated

work. We anticipate the results of the 28 day inhalation

and 13 week inhalation study with HFC-245fa to be completed in 1996.

Bogdan, Williams, Logsdon, Parker / 3

EE-RM-93-801 COMMENT 269

Table 4. Results of AHAM refrigerator trial 

AHAM RE FRIGE RAT OR 

TRIAL 

DOE Cabinet Energy. Reverse Heat Leakage, 

KwH/day BTU/hr 

Blowing agent HCFC-141b HFC-245fa HCFC-141b HFC-245fa 

Average value 2.071 2.090 270.2 271.7 

Yo Increase vs 0.9 0.5 

HCFC-141b 

Table 5. TEWI analysis AHAM refrigerator trial 

• Assumptions: 

• 100yrtime mrizion 

• 20 yr. appliaD::e lifetime 

• 100% ofHFC-245famlemed 

afulr2Oyr. 

• Contribution from refrigerant 

(l34a) is constant 

Heat Leakage test were performed on each. The results 

are contained in Table 4. The refrigerators produced with 

HFC-245fa had equivalent energy performance to the 

ones produced with HCFC-141b even though there was a 

5% higher k-factor for foams produced with HFC-245fa. 

This is why actual analysis of the foam in its application 

at the temperatures it will be exposed to is important. 

There is an extensive discussion ofk-factor vs. mean temperature included in' a latter portion of this paper. 

If this energy data for the unoptimized refrigerators is 

combined with the GWP for HFC-245fa, a TEWI analysis 

of the refrigerators energy requirements can be calculated. The results are also displayed in Table 5. A comparison of the energy requirement for a refrigerator made 

with HFC-245fa, HCFC-141b and cyclopentane are 

included. 

It is important to understand the assumptions which 

are made in this calculation. These include : the refrigerators are operational in North America, the 100 yr. GWP 

is used for each chemical to determine its direct contribution to global warming in terms of kg CO2 generated, the 

life of the appliance is assumed to be 20 years, at the end 

of the 20 year life all the blowing agent will be released to 

the environment, and for the sake of consistency the fluorocarbon used as the compressor fluid in these examples 

is HFC-134a. 

The result is that the total requirements , both direct 

and indirect, to operate a refrigerator produced with the 

unoptimized HFC-245fa formulations has less TEWI in 

its lifetime than one produced with cyclopentane. Also, it 

requires approximately 8.3% less T~WI due to direct 

energy requirements to operate than one produced with 

cyclopentane. This is a critical concern in regions where a 

consistent supply of electricity or energy production 

Table 6. Summary of toxicity testing conducted on HFC-24Sfa to 

date 

TEST HFC-245fa HCFC-14Ib D-Pentane Isopenlane Cvclopenla..., 

Acute Dennal LD",>2ooo LD",> 2000 noLDso noLO,. noLD", 

mg/l<g mg/l<g reponed reponed reponed 

No irritation No initalion Irritation Irritation Irritation noted 

noted noted noted noted 

Acute LC,.> 

Inhalation 101.300 ppm 

Screen- Mice 

Cardl3c Negauveat 10.000 ppm xxx xxx Weak 

Sensitization 10.000 and Threshold Sensitizer 

20.000 ppm 

Human Weak NOI active up xxx xxx xxx 

Lympocyte activity at to 35% vlv 

3O'k vlv 

without 59 

Mouse Not active at Not active up xxx xxx xxx 

Micronucleus 100.000 ppm to 36.000 

. ppm 

Ames Assay Not Active Not Active xxx Not Active xx> 

Acute (4) Hr LC,.> LC,.- LC,.- xxx xxx 

Inhalatlon- 200.000 ppm 62.000 ppm 11.260 ppm 

Rats 

xxx- Test results not reponed 

Note: No exposure level was reponed for cyclopentane only a classificalJon as a weak sensitizer 

capacity is not adequate enough to meet the needs of the 

population. Additional improvements in the performance 

of HFC-2~5fa foam cap, be expected as formulation optimization is done over the next few years. Hence, the energy consumption of refrigerators prepared with HFC-245fa 

should be even lower. This points out the importance of 

not only considering the direct chemical effect of a sub-

.' stance .but also considering the total energy requirements 

of the system in which it is used. 

In addition to the environmental aspects, the discussion 

of the long term breakdown products of CFC substitutes, 

into trifluoroacetic acid (TFA) has been occurring. 

Research work has recently been completed which identifies the long term breakdown products of HFC-245fa as 

HF and CO2, Therefore, the use of HFC-245fa does not 

lead to the formation ofTFAin the environment. 

TOXICOLOGICAL PROPERTIES 

It is critical that the toxicity of any alternative foam 

blowing agent candidate be fully defined. This data is 

required not only to set industrial exposure guidelines 

during storage, handling, and use of the blowing agent 

during the foam manufacturing process, but is also important in risk assessment analyses ofthe final foam product 

in its intended use and is critical to considerations in 

product stewardship and responsible care. 

The HCFC and HFC molecules commercialized over the 

past several years, including HCFC-141b, have been 

extensively tested for toxicity characteristics. HFC-245fa 

is currently undergoing a similar toxicity testing protocol. 

A summary of the toxicity testing conducted on HFC245fa to date is included in Table 6. Data on HCFC-141b 

and hydrocarbons is also included for comparison. 

The test results support that HFC-245fa has a very low 

order of acute toxicity equivalent to or better than those. 

reported for HCFC-141b. We are continuing our toxicity 

testing and have summarized in Table 7 our anticipated 

work. We anticipate the results of the 28 day inhalation 

and 13 week inhalation study with HFC-245fa to be completed in 1996. 

Bogdan, Williams, Logsdon, Parker I 3 
Table 7. Additional toxicological studies

Planned Studies

• 28 Day Inhalation

• 13 Week Inhalation

• Rat & Rabbit Teratology

• Environmental

• Octanol/water partition coefficient

• Algae

• Daphnia

• Fish

Optional Studies

• Reproductive toxicity

• Sub-chronic toxicity

• Repeated dose studies

• Global compliance

Table 8. HFC-245fa compatibility with plastics and elastomers

Compatible Not Compatible

• Polyethylene • Nitrile ( marginal)

• Polypropylene • HNBR

• PTFE • Viton

• EPDM • Epichlorohydrin

• Neoprene

• Buna-N

Material is immersed inIIFC-245fa for 2 weeks at room temperature

Pass/Fail Criteriar Swelling < 20& or shrinkage < 5%

Table 9. Formulations for base premix

Premix pb%

Thanol R470X` ' 100

Ttab B8466' 1.5

D DR81720 '' 1.0

Premix blowing agent ratio (75/25 wt%)

Eastman Chemical

o' Huntsman Chemical

"'Air Products & Chemicals

THERMAL AND HYDROLYTIC STABILITY

In our previous paper(I), we reported that HFC-245fa

has been evaluated for storage stability at temperatures

up to 200°C with no evidence of blowing agent decomposition. This testing was done on neat HFC-245fa, HFC245fa with 300 ppm water added, and both neat and "wet"

HFC-245fa in the presence of 302 stainless steel, 3003

aluminum, or both. Additional testing has been done with

cold rolled steel, brass and lead with similar results.

Limited testing has also been completed on several gasket

materials and plastics. These results are summarized in

Table 8.

It is important to note that these tests represent the

suitability for contact of these materials with neat HFC245fa and do not necessarily represent their suitability for

contact with "B-components" containing HFC-245fa as is

the case in foam processing equipment. A test was conducted immersing Viton gasket material at room temperature for 2 weeks to neat samples of CFC-11SBA, HCFC14lb and HFC-245fa and also to neat "B-components" and

"B-components" containing each of the blowing agents.

The formulation for the "B-components" used is contained

in Table 9. The results of the testing are contained in

Table 10. Although only weight gain is reported in this

paper other dimensional measurements were also taken.

The data for length, width and hardness follow the same

trend as weight. Therefore, before using any "B-components" in equipment independent of blowing agent it is

highly recommended that a brief stability test be conducted on the "wetted" gaskets and seals in the unit.

POLYOL SOLUBILITY

Solubility of a blowing agent is a critical variable in the

foaming reaction. It is determines both the density and

insulation properties of the foam. The solubility of HFC245fa was tested in various polyols and polyol blends. The

4 if Bogdan, Williams, Logsdon, Parker

Table 10. Compatibility of viton gasket with blowing agents and

blowing agent premix formulations

Piton Gasket Compatibility

HFC-245fa

HCFC-141b

CFC-11SBA

premix

0 5 10

% Weight Gain

15

OBA & Premix

n Neat Blowing agent

Table 11. Resin formulations

Resin II Coat nt pbw

1 Pluracol 975 ' 100

Te ostabB-8404 1.5

Pol cat 8 - 2.5

2 Terate 254 100

8

8408 ' 2

MZO K-15 ' 3

DABCO TMR-30 0.5

Water 0.5

Thah R-470X ' 100

LK-443 I

DABCO R-8020 1

4 Multmol 4063 "' too

Te ostab B-8461 1.5

Polycat 8 2.5

"BASF

Goldschmidt Chemical

"'Air Products & Chemicals

''Eastman Chemical

"'Bayer

Men 4

Men 3

Mein 2

Men1

Kneel 975

824

V°ranot 390

T aW R-470X

Taroi 235

Taste 2541

Taste 254°

Tana 203

Muaranol 4063

Table 12.

Solubility of HFC-245fa In Polyois and Resins

0 10 20 30 40 50 60 70

HFC-245fa Dlasoived phpp

polyol blends tested , listed in Table 11, represent a typical spray, appliance, PIR and panel formulation. A known

amount of polyol or resin and an excess amount of HFC245fa was added to a calibrated tube. The tubes were

sealed and allowed to equilibrate for 24 hours. If separation occurred the height of the blowing agent was measured and the amount dissolved in the polyol was calculated. The data available to date is summarized in Table

12. Additional testing is currently in progress and will be

presented as it becomes available.

EE-RM-93-801 COMMENT 269

Table 7. Additional toxicological studies 

Planned Studies Studies 

• 28 Day Inhalation • Reproductive toxlcny 

• 13 Week Inhalation • Sub-chronic toxicity 

• Rat & Rabbit Tenttolog) • Repeated dose siudies 

• Environmental • Global comphance 

• Octanollwater panJuon coefficient 

• Algae 

• Daphnia 

• FISh 

Table 8. HFC-24Sfa compatibility with plastics and elastomers 

Comoalible Not Compatible 

• Polyethylene • Nitrile ( marginal) 

• Polypropylene • HNBR 

• PTFE • Vuon 

• EPDM • Epichlorohydrin 

• Neoprene 

• Buna·N 

· Malenal is immersed mHFC-24Sfa for 2 weeks at room temperature 

· PassIF.il Criteria' Swelhng < 20,. or shnnkage < 5'" 

Table 9. Formulations for base premix 

Premix 

Thanol R470X' , 

Tet20stab B8466 • 

Dabco R8020 .' 

Premix blowillg agnt ratio (75125 wr%) 

" Eastman Cherrucal 

c! Huntsman Chemical 

L" Air Products & Chemicals 

pb .. 

100 

1.5 

1.0 

THERMAL AND HYDROLYTIC STABILITY 

In our previous paper(I1, we reported that HFC-245fa 

has been evaluated for storage stability at temperatures 

up to 200°C with no evidence of blowing agent decomposition. This testing was done on neat HFC-245fa, HFC245fa with 300 ppm water added, and both neat and "wet" 

HFC-245fa in the presence of 302 stainless steel, 3003 

aluminum, or both. Additional testing has been done with 

cold rolled steel, brass and lead with similar results. 

Limited testing has also been completed on several gasket 

materials and plastics. These results are summarized in 

Table 8. 

It is important to note that these tests represent the 

suitability for contact of these materials with neat HFC245fa and do not necessarily represent their suitability for 

contact with "B-components" containing HFC-245fa as is 

the case in foam processing equipment. A test was conducted immersing Viton gasket material at room temperature for 2 weeks to neat samples of CFC-llSBA, HCFC141b and HFC-245fa and also to neat "B-components" and 

"B-components" containing each of the blowing agents. 

The formulation for the "B-components" used is contained 

in Table 9. The results of the testing are contained in 

Table 10. Although only weight gain is reported in this 

paper other dimensional measurements were also taken. 

The data for length, width and hardness follow the same 

trend as weight. Therefore, before using any "B-components" in equipment independent of blowing agent it is 

highly recommended that a brief stability test be conducted on the "wetted" gaskets and seals in the unit. 

POLYOL SOLUBILITY 

Solubility of a blowing agent is a critical variable in the 

foaming reaction. It is determines both the density and 

insulation properties of the foam. The solubility of HFC245fa was tested in various polyols and polyol blends. The 

4 I Bogdan, Wl1liams, Logsdon, Parker 

: 

Table 10. Compatibility ofviton gasket with blowing agents and 

blowing agent premix formulations 

VitO" Gasket Compatibility 

I I 

HFC-245fa 

HCFC-141b 

-

OBA. Premix 

CFC-11SBA • Neat Blowing agent 

premix 

o 5 10 15 

% Weight Gain 

Table 11. Resin formulations 

Resin # 

I 

2 

'. 

4 

" BASF 

(2)GoJdschmidl Chemical 

!3! Air Products & Chemlca1s 

141 Eastman Chemical 

CSJBayer 

Component 

Pluracol 97S . 

TegostabB-8404 w 

Polyeat8 . 

Telate 254 

Tegostab B-8408 • 

DABCO K·15 '" 

DABCO 1MR-30 '" 

Water 

Thahol R-470X «. 

LK-443 ." 

DABCO R-8020 '" 

Multranol 4063 '" 

Tegostab B-8461 ., 

Polvcat 8 '" 

Table 12. 

pbw 

100 

1.5 

2.5 

100 

2 

3 

0.5 

0.5 

100 

I 

I 

100 

1.5 

2.5 

Solubility of HFC-245fa In PoIyoIs and Realns 

~3 

~2 

Piuraco{ 975 

_824 

Thanol R-4&70X 

T_0I235 

Terato 25(1 

Tertto 2S4c 

T ..... 203 

Munraool <4063 

~ 

o 10 20 30 40 50 60 

HFC-245fa DluolVed phpp 

70 

polyol blends tested, listed in Table 11, represent a typi-

. cal spray, appliance, PIR and panel formulation. A known 

amount of polyol or resin and an excess amount of HFC245fa was added to a calibrated tube. The tubes were 

sealed and allowed to equilibrate for 24 hours. If separation occurred the height of the blowing agent was measured and the amount dissolved in the'polyol was calculated.- The data available to date is summarized in Table 

12. Additional testing is currently in progress and will be 

presented as it becomes available. 
Table 13. Raw materials and blends used for blowing agent stabilii-y testing

MATERIAL WT RATIO TESTED

(COMPONENT : HFC-245fa

Pol ols 70:30

Catalysts 1:10

Surfactants 1:15

Com atibilizers 1:7

MDI 1:10

Table 14. Raw material chemical stability data

Component Unaffected Affected

Catalysts Polycat 5 DABCO K-15

DABCO TMR-30' Polycat 46'

Curithane 52' -DABCO TMR

DABCO TMR-2

DABCO TMR-3

Compatibilizers N-10-

N-95 '

MD1 Lupranate M-20S'

Lupranate M-70L'

Mondur MR'

Papi 27'

Rubmate M"

Surfactants L5100

L5110

Y 10774

L6900

L5440

DC-9342'

DC-5357'

LK-443 '

Tegostab B-8404

Tegostab B-8458

Tegostab B-8467

Tegostab B-8465'

Te ostab B-84PI

Patrols Voranol 360

Voranol V370'

Voranol V490'

Thanol R-575'

Thanol R-370`

Thanol R-4220'

Thanol R-470X'

Terate 2541`

Thanol R-650X'

Stepanol 2352"

Thanol SF-265'

Notes I Air Products & Chemicals 7. Goldschmidt Chemical

2. Huntsman Chemical 8. Eastman Chemical

3. BASF 9, Hoechst-Celanese

4 Bayer 10. Stepan Co

5 Dow Chemical

6 ICI

Solubility of the blowing agent in the "B-components" is

not only a function of its solubility in the polyol but also is

influenced by the surfactant used in the formulation This

is further discussed in the Surfactant portion of this

report.

COMPATIBILITY WITH FOAM RAW

MATERIALS

In our previous papers' 1i, we have reported some limited data on compatibility of various raw materials with

HFC-245fa. Additional raw materials have been tested

and the results shown in Table 14. A series of sealed tube

studies were done to determine the stability of HFC-245fa

in the presence of certain polyurethane raw materials.

Each raw material was mixed with HFC-245fa in a weight

ratio similar to that which would be typically be found in

a blended polyol component and placed in sealed glass

tubes. The ratios used are listed in Table 13. The tubes

were then placed in a 300 °F oven for 24 hours. The test

was run under these conditions to simulate the exotherm

temperature during the manufacture of a polyurethane

foam. The tubes were removed from the oven and the contents analyzed for decomposition products by gas chromatography.

a

CFC- I I Vapor Pressure at 130 F

40-,

/

35 a-

/

30 I-e

25 130 F /

lo,

20

/

15 70F

10a

5

0

/

0 5 10 1s 20

Wt. % HFC-245fa in P824

Figure 2. Vapor pressure HFC-245fa in P824

The chemical decomposition of a blowing agent such as

HFC-245fa produces a mineral acid (HF) which is reactive

with catalysts in a premix system and thus can influence

foam reactivity. This decomposition reaction can occur

during extended storage of a premix or during the foam

reaction. Since the premix is a mixture of materials , there

is obvious synergy between the components which influence the chemical reactions that occur during the foaming

process and the storage 'of the premix. This test however

does not take this into account . It was designed to detect

any reaction between the HFC-245fa and any single raw

material only.

The affected substances are catalysts. During the introduction of HCFC-141b, it was discovered that use of

potassium carboxylate catalysts such as DABCO K-15*

resulted in increased levels of decomposition products in

the cell gas of foams produced with HCFC-141b. This

reaction was primarily found to occur in polyisocyanurate

foams (31 DABCO K-15* was found to be chemically reactive with HFC-245fa and isocyanates under the test conditions.

This test determines the chemical sensitivity between

HFC-245fa and raw materials which is an important consideration. However, the critical concern is what occurs in

the final foam product. This is discussed in detail along

with the results of toxicity testing on HFC-1234ze in a

later portion of this paper.

PREMIX AND POLYOL VAPOR PRESSURE

From both an environmental and a processing perspective the vapor pressure of the premix is critical. It is a key

part of determining how to effectively minimize fugitive

emissions as well as defining the type of container necessary for shipment and storage of a system.

Two types of vapor pressures measurements have been

taken vapor pressure vs. blowing agent concentration and

vapor pressure vs. temperature. The measurement of

vapor pressure vs. blowing agent concentration gives insight into processing parameters and how to minimize

fugitive emissions. Figure 2 contains a graph of vapor

pressure vs. wt. % HFC-245fa in Pluracol 824. The vapor

pressure of HFC-245fa blend is lower than the vapor pressure of neat CFC-11 at concentration of less than 20 % at

70 °F. Therefore, if the blowing agent is added to a cooled

premix (i.e. below the boiling point of HFC-245fa) fugitive

* Air Products

Bogdan, Williams, Logsdon, Parker / 5

EE-RM-93-801 COMMENT 269

'Table 13. Raw materials and blends used for blowing agent stabili!Jt testing 

MATERIAL WT RATIO TESTED 

(COMPONENT: HFC·Z4Sfa I 

Polvol, 70:30 

Catalvsts 1:10 

Surfactant!. 1:15 

CompatibilJzen. L7 

MDI I:JO 

Table 14. Raw material chemical stability data 

Comoonenl 

CaJaiysls 

Compatibiliurs 

MDi 

Surfactant! 

Polyols 

~ote!'. J AIr Product~ & Chemlcah 

.2 Huntsman Chemrcal 

3. BASF 

4 Bayer 

5 Dow ChemIcal 

6 ICI 

Unallected Affected 

Polycar 5 DABCOK-I~ 

DABCO TMR-30' POIYC3[ 46! 

Curithane 52~ ·DABCO TMR 

DABCO TMR-2 

DABCO TMR·' 

N-IO' 

N-95' 

Lupranale M-20S' 

Lupranate M-70L 3 

Mondur MR4 

Pap' 27~ 

Rubmate MtL5100 

L51 JO 

YI0774 

L6900 

L5440 

DC-934i 

DC-5357' 

LK-443 ' 

Tegostab B-8404 

Tegostab B-8458 

T egostab B-8467 

T egostab B-8465 ~ 

TegoSlab B-84PI 

Voranol360 

Varano I \,370' 

Varanol V490' 

Thanol R-575' 

Thanol R-370' 

Thanal R-42(lf 

Thanol R-470X' 

T erate 254 J "-

Thanol R-650X' 

Stepano! 2352 il 

Thana! SF·26S· 

7 Golds.chmidt Chemlcaj 

8. Eastman Chemical 

9, Hoechst-Celane3c 

10 Stepan Co 

Solubility of the blowing agent in the "B-components" is 

not only a function of its solubility in the polyol but also is 

influenced by the surfactant used in the formulation This 

is further discussed in the Surfactant portion of this 

report. 

COMPATIBILITY WITH FOAM RAW 

MATERIALS 

In our previous papers <11, we have reported some limited data on compatibility of various raw materials with 

HFC-245fa. Additional raw materials have been tested 

and the results shown in Table 14. A series of sealed tube 

studies were done to determine the stability ofHFC-245fa 

in the presence of certain polyurethane raw materials. 

Each raw material was mixed with HFC-245fa in a weight 

ratio similar to that which would be typically be found in 

a blended polyol component and placed in sealed glass 

tubes. The ratios used are listed in Table 13. The tubes 

were then placed in a 300 of oven for 24 hours. The test 

was run under these conditions to simulate the exotherm 

temperature during the manufacture of a polyurethane 

foam. The tubes were removed from the oven and the contents analyzed for decomposition products by gas chromatography. 

CFC· I I Vapor Pressure at 130 F 

40 . -. --.. ------. ----. -,- - - - - -.. 35 

...... 30 

.!!! ! 25 

f 20 CI) == 

CI) 15 f 

Q. 10 

5 

0 

0 

/ 

/ 

/ 

,-

/ 

/ 

,-

,,/ 

5 

,- I30F ,- ,- ,-

/' 

10 

,. ,. 

,. ,. ,. 

Wt. % HFC-245fa In P824 

15 

Figure 2. Vapor pressure HFC-245fa in P824 

20 

The chemical decomposition of a blowing agent such as 

HFC-245fa produces a mineral acid (HF) which is reactive 

with catalysts in a premix system and thus can influence 

foam reactivity. This decomposition reaction can occur 

during extended storage of a premix or during the foam 

reaction. Since the premix is a mixture of materials , there 

is obvious synergy between the components which influence the chemical reactipns that occur during the foaming 

process iUld the storage ·of the premix. This test ,however 

does not take this into account. It was designed to detect 

any reaction between the HFC-245fa and any single raw 

material only. . 

The affected substances are catalysts. During the introduction of HCFC-141b, it was discovered that use of 

potassium carboxylate catalysts such as DABCO K-15* 

resulted in increased levels of decomposition products in 

the cell gas of foams produced with HCFC-141b. This 

reaction was primarily found to occur in polyisocyanurate 

foams.(3) DABCO K-15* was found to be chemically reactive with HFC-245fa and isocyanates under the test conditions. 

This test determines the chemical sensitivity between 

HFC-245fa and raw materials which is an important consideration. However, the critical concern is what occurs in 

the final foam product. This is discussed in detail along 

with the results of toxicity testing on HFC-1234ze in a 

later portion of this paper. 

PREMIX AND POLYOL VAPOR PRESSURE 

From both an environmental and a processing perspective the vapor pressure of the premix is critical. It is a key 

part of determining how to effectively minimize fugitive 

emissions as well as defining the type of container necessary for shipment and storage of a system. 

'!\vo types of vapor pressures measurements have been 

taken vapor pressure vs. blowing agent concentration and 

vapor pressure vs. temperature. The measurement of 

vapor pressure vs. blowing agent concentration gives insight into processing parameters and how to minimize 

fugitive emissions. Figure 2 contains a graph of vapor 

pressure vs. wt. % HFC-245fa in Pluracol 824. The vapor 

pressure ofHFC-245fa blend is lower than the vapor pressure of neat CFC-ll at concentration of less than 20 % at 

70 OF. Therefore, if the blowing agent is added to a cooled 

premix ( i.e. below the boiling point ofHFC-245fa) fugitive 

* Air Products 

Bogdan, Williams, Logsdon, Parker I 5 
Table 15. Premix and blowing agent concentration

Premix Concentration

66% Polyether

65% Polyester

72% Sucrose

HFC-245fa Concentration

34%

35%

28%

emissions should be minimal. This was demonstrated in a

recent AHAM refrigerator trial where HFC-245fa was

added subsurface to a precooled premix in an open processing tank . Typically premix blending is done in closed

containers. Therefore, the loss of less than 4% during the

mixing of the blowing agent into the premix and the

transfer of the premix into the tanks of the processing

equipment is considered excellent.

Vapor pressure measurements are also useful in determining the appropriate shipping containers . Vapor pressure is a very critical concern in the systems business

because currently a significant portion of the systems sold

are shipped in drums or totebins. These containers traditionally have low pressure ratings. The vapor- pressure of

three commercial spray foam systems containing HFC245fa were measured. These were sucrose, polyether and

polyester polyol spray formulations. The premix and blowing agent concentrations are listed in Table 15. The containers were filled to 93% of capacity to simulate drum

storage conditions. The results are contained in Table 16.

There is a marked difference in vapor pressure of the systems tested. It is in part due to the different quantity of

HFC-245fa dissolved in each.

At the low temperature of 50°F all three systems have

similar vapor pressures. This supports the findings that

fugitive emissions should not pose a problem at processing temperatures below 60°F. However, at elevated temperatures the vapor pressure is directly proportional to

the quantity of HFC-245fa used in the system. The formulations exceed the vapor pressure rating of most totes

(1 atm) at 68°F. Drum pressure ratings vary dependent

upon the drum gauge chosen. This is an area where more

data needs to be generated.

STABILITY DURING THE FOAMING

REACTION

The stability of HFC-245fa during the foaming reaction

is an area under study. It was discovered that under certain conditions during the foaming reaction it was possible for HCFC-141b to decompose into HCFC-1131a and

HCFC-151a. The decomposition took place more readily in

PIR than PUR foams and was highly correlated to the levels of potassium octoate present in the system.l3'

A well defined research program has begun to identify

what decomposition products, if any, were formed during

foaming with HFC-245fa toxicity testing would then be

conducted on these products and conditions which promote decomposition reactions would be identified. The initial foams produced with HFC-245fa were analyzed for

cell gas content (4). Only one decomposition product was

identified, HFC-1234ze ( 1,3,3,3 tetrafluoropropene). It is

possible for this structure to exist in both a cis and a trans

orientation. The decomposition reaction is shown in Table

17.

Data on foams prepared from the Class I* and Class II*

panel formulations and the spray formulation reported in

our previous papers") (21 indicate that very little or no decomposition of the blowing agent occurs during the foamTable 16. Vapor pressure measurements vs temperature in spray

foam formulations

0

50 59 68 77 86 95

Temperature ° F

-POLYETTER ---POLYESTER -a- SUCROSE

Table 17. Reaction mechanism for the formation of HFC-1234ze

C F s - C H - C F C F, - C H = C F + H F

H F C - 2 4 5 f a HFC -1 234ze

Table 18. Variables for decomposition study

Variable Level I Level 2

Trimer Catalyst DABCOTM K-15 ' DABCO" TMR-2

Reactivity Low- 50 sec Hi - 32 sec

Index 250 350

Amine Catalyst DABCOTM TMR-30 Polycatt" 8"

Polyol Stepanpol PS-2352 Terate 2541°'

Blowing Agent Package 35 pbw HFC-245fa! 25 pbw HFC-245fa/

0 pbw water I pbw water

Air Products & Chemicals

'''Stepan Chemical

13iHoerchst -Celanese

ing reaction. As with HCFC-141b, it was found that the

decomposition reaction occurs primarily in PIR foams. It

was also discovered that the reaction mechanism favored

the formation of the trans isomer over the cis isomer in a

4:1 ratio. In response to this information, HFC-1234ze

trans and HFC-1234ze cis isomers were purified and submitted for limited toxicity testing. Toxicity testing on

HFC-1234ze trans isomer has been completed. The limited amount of data available on HFC-1234ze trans implies

that it is not highly toxic or mutagenic. Toxicity testing is

currently scheduled for the cis isomer.

A new program was initiated to determine what conditions favored the decomposition reaction in polyisocyanurate foams. The program was modeled after the work completed with HCFC-141b13>. A series of 16 experiments

were run to define the importance of 6 key variables.' The

variables chosen were: trimer catalyst type [ potassium

carboxylate, DABCOTm K-15(Tl) vs. a quaternary ammonium carboxylate DABCOT"' TMR-2 (T2)], reactivity [fast

(R2) vs. slow (Rl) gel time] , foam index [250 (Il) vs. 350

(I2)], amine catalyst type [a volatile monoamine, N,Ndimethylcyclohexylamine, PolycatTM 8 (A2), vs. a less

volatile triamine, DABCO T14TMR-30 (Al)], polyol type

[StepanpolTM PS-2352 (Pl) vs. TerateTM 2541 (P2)], and

blowing agent package [HFC-245fa only (Bl) vs. HFC245fa plus water (B2)]. Two levels or types of each variable were set They are shown in Table 18. This arrived

*This numerical flame spread is not intended to reflect hazards presented

by this or any other under actual fire conditions.

6 / Bogdan, Williams, Logsdon, Parker

EE-RM-93-801 COMMENT 269

Table 15. Premix and blowing agent concentration 

Premix Concentration HFC·24sr. Concentration 

669< Polvether 

65% Polvester 35'K 

72% Sucrose 281t 

emissions should be minimal. This was demonstrated in a 

recent AHAM refrigerator trial where HFC-245fa was 

added subsurface to a precooled premix in an open processing tank . Typically premix blending is done in closed 

containers. Therefore, the loss of less than 4% during the 

mixing of the blowing agent into the premix and the 

transfer of the premix into the tanks of the processing 

equipment is considered excellent. _ 

Vapor pressure measurements are also useful in determining the appropriate shipping containers. Vapor pressure is a very critical concern in the systems business 

because currently a significant portion of the systems sold 

are shipped in drums or totebins. These containers traditionally have low pressure ratings. The vapor- pressure of 

three commercial spray foam systems containing HFC245fa were measured. These were sucrose, polyether and 

polyester polyol spray formulations. The premix and blowing agent concentrations are listed in Table 15. The containers were filled to 93% of capacity to simulate drum 

storage condition!!. The results are contained in Table 16. 

There is a marked difference in vapor pressure of the systems tested. It is in part due to the different quantity of 

HFC-245fa dissolved in each. 

At the low temperature of 50°F all three systems have 

similar vapor pressures. This supports the findings that 

fugitive emissions should not pose a problem at processing temperatures below 60°F. However, at elevated temperatures the vapor pressure is directly proportional to 

the quantity of HFC-245fa used in the system. The formulations exceed the vapor pressure rating of most totes 

(1 atm) at 68°F. Drum pressure ratings vary dependent 

upon the drum gauge chosen. This is an area where more 

data needs to be generated: 

STABILITY DURING THE FOAMING 

REACTION 

The stability ofHFC-245fa during the foaming reaction 

is an area under study. It was discovered that under certain conditions during the foaming reaction it was possible for HCFC-141b to decompose into HCFC-1131a and 

HCFC-151a. The decomposition took place more readily in 

PIR than PUR foams and was highly correlated to the levels of potassium octoate present in the system. (3) 

A well defined research program has begun to identify 

what decomposition products, if any, were formed during 

foaming with HFC-245fa ,toxicity testing would then be 

conducted on these products and conditions which promote decomposition reactions would be identified. The initial foams produced with HFC-245fa were analyzed for 

cell gas content(4). Only one decomposition product was 

identified, HFC-1234ze ( 1,3,3,3 tetrafluoropropene). It is 

possible for this structure to exist in both a cis and a trans 

orientation. The decomposition reaction is shown in Table 

17. 

Data on foams prepared from the Class I* and Class II* 

panel formulations and the spray formulation reported in 

our previous papers(1) (2) indicate that very little or no decomposition of the blowing agent occurs during the foam6 I Bogdan, Williams, Logsdon, Parker 

Table 16. Vapor pressure measurements vs temperature in spray 

foam formulations 

30 T------------------------------

c;- 25 

iii 20 .e: 

CII 

.. 15 ::J 

III 

III 10 CII 

.. 

Q. 5 

O+-----~----~----~----_r----~ 

50 59 68 77 86 95 

Temperature 0 F 

I--POLYETHER --POLYESTER --SUCROSE! 

Table 17. Reaction mechanism for the formation of HFC-1234ze 

CF 3 ·CH 2 ·CF CF 3 -CH=CF+HF 

HFC-245fa HFC-1234ze 

;fable 18. Variables for decomposition study 

Variable 

Tnmer Catalyst 

Reactivity 

Index 

Amine Catalyst 

Polvol 

Bl;wing Agent Package 

01 Air Products & Chemicals 

/~I Stepan Chemical 

01 Hoerchst -Celanese 

Level J 

DABCO'" K-15 ," 

Low- 50 sec 

250 

DABCO'" TMR·30 '" 

Stepanpol PS·2352 ," 

35 pbw HFC-245fa/ 

o pbw water 

Levell 

DABCOTM TMR·2' ' Hi - 32 sec 

350 

PoJycatTt.t 8<: 

Terate 2541°> 

25 pbw HFC-24Sfa/ 

1 pbw wafer 

ing reaction. As with HCFC-141b, it was found that the 

decomposition reaction occurs primarily in PIR foams. It 

was also discovered that the reaction mechanism favored 

the formation of the trans isomer over the cis isomer in a 

4:1 ratio, In response to this information, HFC-1234ze 

trans and HFC-1234ze cis isomers were purified and submitted for limited toxicity testing. 1bxicity testing on 

HFC-1234ze trans isomer has been completed. The limited amount of data available on HFC-1234ze trans implies 

that it is not highly toxic or mutagenic. 1bxicity testing is 

currently scheduled for the cis isomer. 

A new program was initiated to determine what conditions favored the decomposition reaction in polyisocyanurate foams. The program was modeled after the work completed with HCFC-141b(3). A series of 16 experiments 

were run to define the importance of 6 key variables.' The 

variables chosen were: trimer catalyst type [ potassium 

carboxylate, DABCOTM K-15(T1) vs. a quaternary ammonium carboxylate DABCOTM TMR-2 (T2)], reactivity [fast 

(R2) vs. slow (R1) gel time] , foam index [250 (Il) vs. 350 

(12)], amine catalyst type [a volatile monoamine, N,Ndimethylcyclohexylamine, PolycatTM 8 (A2), vs. a less 

volatile triamine, DABCO TMTMR-30 (AI)], polyol type 

[StepanpolTM PS-2352 (PI) vs. ThrateTM 2541 (P2)], and 

blowing agent package lHFC-245fa only (B1) vs. HFC245fa plus water (B2)]. Two levels or types of each variable were set. They are shown in Table 18. This arrived 

*This numerical flame spread is not intended to reflect hazards presented 

by this or any other under actual fire conditions. ' 
° Table 19. 16 Experiments for study on formation of HFC-1234ze

I of water Index amine trimer time

1 stepan 0 250 tmr30 k15 50

2 terate 1 250 k15 50

3 stepan 1 350 tmr3O k15 50

4 terate 0 350 pc8 k15 50

5 terate 1 250 tmr30 k15 30

6 stepan 0 250 k15 30

7 terate 0 350 tmr30 k15 30

8 stepan 1 350 PC8 k15 30

9 terate 1 250 tmr30 tmr2 50

10 stepan 0 250 PC8 tmr2 50

11 terate 0 350 tmr30 tmr2 50

12 stepan 1 350 c8 tmr2 50

13 stepan 0 250 tmr30 tmr2 30

14 terate 1 250 tmr2 30

15 ste an 1 350 tmr30 tm12 30

16 terate 0 350 tmr2 30

Stepan refers to Stepanol PS-2352

Terate refers to Terate 2541

HI

Lou

Y. wara uimc amne amt

Figure 4. Analysis of experimental data

at the 16 experiments listed in Table 19. On each foam

reactivity, cell gas content, peak exotherm and density

were determined. Analysis of the data using the Taguchi

method yield s the results in Figure 4. Each point represents an average for all the, experimental results for that

variable.

Based upon experimental error analysis, the two variables of the six tested with the strongest effect to produce

the HFC-1234ze trans isomer is reaction time and trimer

concentration level. In experiments where the reaction

time was 30 seconds and DABCO K-15 was used, the levels of HFC-1234ze trans produced were on average two

times higher than in reactions where the reaction time

was 50 seconds and DABCO TMR-2 was used. It is important to realize that in any reaction the catalyst levels are

what determines the reactivity of the system. Therefore,

these should not be considered independent effects as also

the case with the *amine catalyst and index results. This

study is continuing to determine if there is any effect on

the HFC-1234ze trans levels in the foam as it ages. It is

important to note here that under these conditions HFC1234ze trans can be generated but the limited toxicity

data indicates that HFC-1234ze trans does not appear to

be highly toxic or mutagenic.

SURFACTANTS

Considerable work has been conducted over the past

several months to further define the performance of HFC245fa as a foam blowing agent. The choice of surfactant is

Table 20. Formulation used for surfactant evaluation

component Pbw

B- component

Voranol 370 70

Tero1375 " 30

Polycat 5 0.7

Polycat41 0.5

Water 1.0

Surfactant 2.5

HFC-245fa 24

A-component

Mondur MR 129

Index 125

Temperature 60 ° F

"'Dow Chemical

'2 oXID Incorporated

Air Products & Chemicals

Bayer

80 r

Table 21. Surfactant vs. closed cell content

B8404 B8409 B8418 88433 88462

Surfactant

a critical part of optimization of the k-factor of a foam. In

the transition from CFC-11 to HCFC-141b, it was discovered that the best foam performance in terms of both kfactor and physical properties was achieved with the use

of different surfactants. Some very preliminary work has

been completed using Goldschmidt surfactants studying

the effect different surfactants have on the physical properties of foams produced with HFC-245fa. The initial

work was done with the appliance formulation listed in

Table 20. The foam was produced in L-molds and samples

were taken to determine the effect each surfactant had on

closed cell content, k-factor, flow and physical properties.

The tests suggest the use of Goldschmidt B8404 and

B8462 produced foams with higher closed cell contents

(Table 21) and lower k-factors than those produced with

other surfactants (Table 22). They also produced foams

with better flowability (Table 23) and physical properties

than other Goldschmidt surfactants. As a result of this

work, the use of Goldschmidt B8404 and B8462 were

found to perform better than other Goldschmidt surfactants tested. Similar work has been completed on a series

of OSi surfactants. To date OSi surfactant L-6900 appears

to be the best of the Osi surfactants tested. Additional surfactant screening is currently in progress and will be

reported in subsequent papers.

K-FACTOR VS TIME AND MEAN

TEMPERATURE

We have previously reported that foams produced with

HFC-245fa age at a slower rate than foams produced with

Bogdan, Williams, Logsdon, Parker / 7

EE-RM-93-801 COMMENT 269

, :rable 19. 16 Experiments for study on formation of HFC-1234ze 

j oolvol water 

1 stepan 0 

2 terate 1 

3 stepan 1 

4 terate 0 

5 terate 1 

6 stepan 0 

7 terate 0 

8 stepan 1 

9 terate 1 

10 stepan 0 

11 terate 0 

12 stepan 1 

13 stepan 0 

14 terate 1 

15 stepan 1 

16 terate 0 

Stepan refers to Stepanol PS-2352 

Terate refers to Terate 2541 

Index amine 

250 tmr30 

250 oc8 

350 tmr30 

350 oc8 

250 tmr30 

250 oc8 

350 tmr30 

350 oc8 

250 tmr30 

250 oc8 

350 tmr30 

350 pcB 

250 tmr30 

250 oc8 

350 tmr30 

350 oc8 

Ma in Effects for HFC-1234ze trans 

HI 

trimer time 

k15 50 

k15 50 

k15 50 

k15 50 

k15 30 

k15 30 

k15 30 

k15 30 

tmr2 50 

tmr2 50 

tmr2 50 

tmr2 50 

tmr2 30 

tmr2 30 

tmr2 30 

tmr2 30 

·--·~/·\·················· LOW 

polyoJ lure 

Figure 4. Analysis of experimental data 

at the 16 experiments listed in Table 19. On each foam 

reactivity, cell gas content, peak exotherm and density 

were determined. Analysis of the data using the Taguchi 

method yield s the results in Figure 4. Each point represents an average for all the. experimental results for that 

variable. 

Based upon experimental error analysis, the two variables of the six tested with the strongest effect to produce 

the HFC-1234ze trans isomer is reaction time and trimer 

concentration level. In experiments where the reaction 

time was 30 seconds and DABCO K-15 was used, the levels of HFC-1234ze trans produced were on average two 

times higher than in reactions where the reaction time 

was 50 seconds and DABCO TMR-2 was used. It is important to realize that in any reaction the catalyst levels are 

what determines the reactivity of the system. Therefore, 

these should not be considered independent effects as also 

the case with the'amine catalyst and index results. This 

study is continuing to determine if there is any effect on 

the HFC-1234ze trans levels in the foam as it ages. It is 

important to note here that under these conditions HFC1234ze trans can be generated but the limited toxicity 

data indicates that HFC-1234ze trans does not appear to 

be highly toxic or mutagenic. 

SURFACTANTS 

Considerable work has been conducted over the past 

several months to further define the performance of HFC245fa as a foam blowing agent. The choice of surfactant is 

Table 20. Formulation used for surfactant evaluation 

Com 

B- component 

Varanol 370 '" 

Terol375 " 

Polycat 5 (31 

Polycat41 0, 

Water 

Surfactanl 

HFC-245fa 

A -component 

Mondur MR ~ .. ! 

Index 125 

Temperature 60 0 F 

fI)Dow Chemical 

m OlOD Incorporate<! 

(3) Air Products & Chemicals 

(4) Bayer 

70 

30 

0.7 

0.5 

1.0 

2.5 

24 

129 

Table 21. Surfactant vs. closed cell content 

100 

-

c 95 II -

C 

0 

0 

" 90 II 

III 

0 

0 85 'if80 

88404 88409 88418 

Surfactant 

88433 88462 

a critical part of optimization of the k-factor of a foam. In 

the transition from CFC-ll to HCFC-141b, it was discovered that the best foam performance in terms of both kfactor and physical properties was achieved with the use 

of different surfactants. Some very preliminary work has 

been completed using Goldschmidt surfactants studying 

the effect different surfactants have on the physical properties of foams produced with HFC-245fa. The initial 

work was done with the appliance formulation listed in 

Table 20. The foam was produced in L-molds and samples 

were taken to determine the effect each surfactant had on 

closed cell content, k-factor, flow and physical properties. 

The tests suggest the use of Goldschmidt B8404 and 

B8462 produced foams with higher closed cell contents 

(Table 21) and lower k-factors than those produced with 

other surfactants (Table 22). They also produced foams 

with better flowability (Table 23) and physical properties 

than other Goldschmidt surfactants. As a result of this 

work, the use of Goldschmidt B8404 and B8462 were 

found to perform better than other Goldschmidt surfactants tested. Similar work has been completed on a series 

of OSi surfactants. 1b date OSi surfactant L-6900 appears 

to be the best of the Osi surfactants tested. Additional surfactant screening is currently in progress and will be 

reported in subsequent papers. 

K-FACTOR VS TIME AND MEAN 

TEMPERATURE 

We have previously reported that foams produced with 

HFC-245fa age at a slower rate than foams produced with 

Bogdan, Williams, Logsdon, Parker / 7 
' 0.16

0.155

0.15

0.145

LL

0.14

0.135

0.13

0.5

0.45

0.4

0.35

0.3

0.25

0.2

c 0.15

LL 0.1

0.05

0

Table 22. Surfactant vs. k-factor

B8404 B8409 88418 B8433 88460 B8462

Surfactant

Table 23. Surfactant vs. flowability

B8404 88409 B8418 B8433 B8451 B8460 B8462

Surfactant

HCFC-141b and CFC-11.12' Also, the results of the AHAM

appliance trial demonstrated the importance of not only

comparing foam k-factors but also comparing them at the

temperature of the application.

As a result a study of k-factor vs. mean temperature vs.

time for a series of foams was run. The formulations used

to prepare the foams is listed in Table 24. Foams were

prepared with HFC-245fa, HCFC-141b, CFC-11SBA and

cyclopentane. Both handmix and machine foams were

made using the same formulation . The machine foams

were prepared using a Martin Sweets low pressure

machine. Machine foams were not prepared for cyclopentane since the equipment available is not explosion proof.

The foams were poured into panels. The density and reactivity for the foams produced are summarized in Table 25.

Note the panels were formulated to a 2.2 lb. density to

minimize shrinkage during aging of the cyclopentane

foams.

The k-factor of the foams were measured over time comparing the aging characteristics of the HFC-245fa and

HCFC-141b foams (Figure 5). The HFC-245fa foams age

at a slower rate than the HCFC-141b foams. This effect is

found at all temperatures tested. Figure 6 shows the kfactor vs. mean temperature for the HFC-245fa , HCFC141b and the cyclopentane foam at 56 days. The k-factor

for the HFC-245fa foams is significantly lower than the kfactor for the HCFC-141b and cyclopentane foams at all

temperatures. The k-factor for the HFC-245fa foam is

equivalent to the k-factor for foam produced with CFC11SBA at a mean temperature of 18 °F. This implies that

in cold applications such as freezers or cryogenic tank

insulation foams produced with HFC-245fa will give the

Table 24. Formulations

Component CFC-llSBA H T

CFC-1416 cyclopentane95%

HFC-245fa

-- -

__

w

0X717 Thanol R 47

_ __

55 55 55 55

Plurocol975 '7 45 45 45 45

Ter ostab B-8466'' 1.5 1.5 1.5 1.5

Polycat 77"' 1.5 1.5 - 1.5 1.5

Water 1.0 1.0 1.0 1.0

CFC-I I SBA 47 -

HCFC-1416 40

Cyclo mane 95% 24

HFC-245fa 46

Lu rinate M20S'2' 132 132 132 132

Index 110 110 110 110

Eastman Chemical

°iBASF

t"Goldschmidt Chemical

Table 25. Reactivity and density data

Blowing Agent CFCIISBA

HCFC1416

CP-95' HFC.

245fa

CFCIISBAHCFC1416CP-95'

Test

Reactivity, sec

Cream Time 18 18 22 20(F) 12 14.5 12

Gel Time 52 53 53 80 50 47 94

Tack Free Time 77 72 72 110 70 67 128

Density, lb.

Free Rise 1 .39 1.37 1.43 1.38 1.35 1.35 1.35

Overall Panel -.^ - 2.19 2.21 .' ,. 2.19 2.22 2.24 2.22 2.22

Core 1.93 1. 89 1.84 2 .04 1.96 1.87 2.02

' Cyclopentane - 95% purity

(F)-Froth

insulation performance equal to or superior to CFC-11

foams.

The response of thermal conductivity to mean temperature for these blowing agents is not surprising. Since

HFC-245fa will maintain a higher vapor pressure in the

foam cells at lower temperatures, the k-factor of the foams

blown with HFC-245fa should improve compared to the

HFC-141b'blown foams as the mean temperature decreases. The data tends to confirm that this is the case. Work

will continue in this area to more fully define the relationship between mean temperature, foam age, and thermal conductivity of HFC-245fa blown, foams.

SUMMARY

A considerable body of data has been developed that

demonstrates HFC-245fa is an excellent candidate as a

"third generation" blowing agent for rigid polyurethane

and polyisocyanurate foams. This liquid HFC has a low

order of acute toxicity, is environmentally acceptable, and

is stable in the presence of common foam raw materials

and materials of construction. HFC-245fa has similar

decomposition characteristics to HCFC-141b. Under certain conditions, it can decompose in polyisocyanurate

foams to HFC-1234ze, which toxicity test results imply is

not highly toxic or mutagenic. The formation of HFC1234ze is both reaction time and catalyst dependent, a

similar phenomenon to that found with HCFC-141b.

From a processing perspective,, surfactants such as

Goldschmidt B8404 and B8462 and OSi L-6900 improve

the quality of appliance foams when used with HFC245fa. Additional surfactants will be identified in the

future that will enhance the performance of HFC-245fa.

8 / Bogdan, Williams, Logsdon, Parker

EE-RM-93-801 COMMENT 269

.. 

S 

0 

t1. 

~ 

.-' 0.16 

0.155 

0.15 

0.145 

0.14 

0.135 

0.13 

Table 22. Surfactant VS. k-factor 

B8404 B8409 B8418 88433 88460 88462 

Surfactant 

Table 23. Surfactant vs. flowability 

0.5TWr-----------------------------------

0.45 +.-1---=----------111---=:---..,...--

a 0.4 +t1---II---tIII---.... -~ ... --.. --.... -- E 0.35 -r-.f---__ - __ ---III_-... --II--___ -

.2. 0.3 +.-1--_.1--..... 1----11--__ --.... --__ --

~ 0.25 -r-.f----.--It--... --tl--.... --;II-- i O.2+t1---II---tII~-4I--... --.. --.... --

~ 0.15 +11----41--.... ----1 ... --11--..... 1--... --

~ 0.1 +.-1--_.1--..... 1----11--__ --.... --__ --

0.05 +111---..... --;11----111---.... ---;11---111--

O+-L_~JL-~--_~L-~JL--~---~L-_. 

B8404 B8409 B8418 B8433 B8451 B8460 B8462 

Surfactant 

HCFC-141b and CFC-ll.(2J Also, the results of the AHAM 

appliance trial demonstrated the importance of not only 

comparing foam k-factors but also comparing them at the 

temperature of the application. 

As a result a study ofk-factor vs. mean temperature vs. 

time for a series of foams was run. The formulations used 

to prepare the foams is listed in Table 24. Foams were 

prepared with HFC-245fa, HCFC-141b, CFC-llSBA and 

cyclopentane. Both handmix and machine foams were 

made using the same formulation . The machine foams 

were prepared using a Martin Sweets low pressure 

machine. Machine foams were not prepared for cyclopentane since the equipment available is not explosion proof. 

The foams were poured into panels. The density and reactivity for the foams produced are summarized in Table 25. 

Note the panels were formulated to a 2.2 lb. density to 

minimize shrinkage during aging of the cyclopentane 

foams. 

The k-factor of the foams were measured over time comparing the aging characteristics of the HFC-245fa and 

HCFC-141b foams (Figure 5). The HFC-245fa foams age 

at a slower rate than the HCFC-141b foams. This effect is 

found at all temperatures tested. Figure 6 shows the kfactor vs. mean temperature for the HFC-245fa , HCFC141b and the cyclopentane foam at 56 days. The k-factor 

for the HFC-245fa foams is significantly lower than the kfactor for the HCFC-141b and cyclopentane foams at all 

temperatures. The k-factor for the HFC-245fa foam is 

equivalent to the k-factor for foam produced with CFCllSBA at a mean temperature of 18 OF. This implies that 

in cold applications such as freezers or cryogenic tank 

insulation foams produced with HFC-245fa Will give the 

8 / Bogdan, Williams, Logsdon, Parker 

Table 24. Formulations 

Componcnl 

Thanol R-470X '" 

Plurocol 975'"' 

Tergostab B-8466 " 

Polvcat 77 •• 

Water 

CFC-II SBA 

HCFC-14Ib 

CvcJQpentane 95'l< 

HFC-245fa 

Luorinate M20Sf2\ 

Index 

(l, Eastman Chemical 

n'BASF 

CFC·IlSBA 

55 

45 

L5 

L5 

LO 

47 

132 

110 

0) Goldschmidt Chemical 

HCFC-141b Cyclopentane95'l< 

w 

55 55 

45 45 

L5 L5 

L5 . L5 

LO LO 

40 

24 

132 132 

110 110 

HFC-245fa 

55 

45 

L5 

' L5 

LO 

46 

13~ 

110 

Table 25. Reactivity and density data 

BlOWing Agent CFCIISBA 

Test 

Reactivity. sec 

Cream Time 18 

Gel Tune 52 

Tack Free Time 77 

Density.lb 

Free Rise 139 

Overall Panel " 2J9 

Core L93 

• Cyclopentane - 95~ purity 

(F)-Froth 

HCFC141b 

18 

53 

72 

137 

2,21 . 

.. L89 

CP-95* HFC- CFC- HCFC- CP-9S* 

245fa IlSBA 141b 

22 20(F) 12 145 12 

53 80 50 47 94 

72 110 70 67 128 

L43 138 135 135 135 

2.19 2.22 2.24 2.22 2.22 

L84 2.04 L96 L87 2.02 

insulation performance equal to or superior to CFC-ll 

foams. 

The response of thermal conductivity to mean temperature for these blowing agents is not surprising. Since 

HFC-245fa will maintain a higher vapor pressure in the 

foam cells at lower temperatures, the k-factor of the foams 

blown with HFC-245fa should improve compared to the 

HFC-141b'blown foams as the mean temperature decreases. The data tends to confirm that this is the case. Work 

will continue in this area to more fully define the relationship between mean temperature, foam age, and thermal conductivity of HFC-245fa blown foams. 

SUMMARY 

A considerable body of data has been developed that 

demonstrates HFC-245fa is an excellent candidate as a 

"third generation" blowing agent for rigid polyurethane 

and polyisocyanurate foams. This liquid .HFC has a low 

order of acute toxicity, is environmentally acceptable, and 

is stable in the presence of common foam raw materials 

and materials of construction. HFC-245fa has similar 

decomposition characteristics to HCFC-141b. Under certain conditions, it can decompose in polyisocyanurate 

foams to HFC-1234ze, which toxicity test results imply is 

not highly toxic or mutagenic. The formation of HFC1234ze is both reaction time and catalyst dependent, a 

similar phenomenon to that found with HCFC-141b. 

From a processing perspective,. surfactants such as 

Goldschmidt B8404 and B8462 and OSi L-6900 improve 

the quality of appliance foams when used with HFC245fa. Additional surfactants will be identified in the 

future that will enhance the performance of HFC-245fa. 
HFC-245fa

Temperature vs. k-Factor

0.17

0.13 ' r ---1 1

18.5 36.5 54.5 72.5 .90.5

Mean Temperature °F

-0 days -1 day -7 days

- 28 days -•- 56 days

Handmix Data

Temperature vs. k-Factor at 56 Days

36.5 54.5 . 72.5

Mean Temperature ° F

- CFC-11 SBA HCFC-141b

- HFC-245fa --Cyclopentane

0.18

0.13 1

HCFC-141 b

Temperature vs. k-Factor

18.5 36.5 54.5 72.5 90.5

Mean Temperature ° F

+-O days --I day 7 days

-28 days -+- 56 days

Figure 5. Aging curves of foams produced with HFC-245fa and

HCFC-141 b

Additional foaming evaluations have further defined

the performance of HFC-245fa as a foam blowing agent.

Foam aging experiments have shown that the k-factors of

foams produced with HFC-245fa age at a slower rate than

foams produced with HCFC-141b. In most cases, the thermal conductivity of HFC-245fa blown foams is superior to

those of HCFC-141b blown foams after several weeks

of aging as unfaced core samples. It has also been shown

that the k-factor of HFC-245fa foams improve relative

to the k-factors of HCFC-141b blown foams as the mean

temperature decreases. In areas of low temperature

applications it has been found that foams produced with

HFC-245fa perform equivalently to those produced with

CFC-11.

0.17

90.5

Figure 6. k-Factor vs. mean temperature for foams produced with

HFC-245fa, HCFC-141b, and cyclopentane

Although additional -work is necessary on HFC-245fa

before it is fully defined as a foam blowing agent, we

believe that this compound will become the blowing agent

of choice for the future. We are committed to the development and commercialization of HFC-245fa as the "third

generation" blowing agent for the polyurethane and poly-.

isocyanurate foam insulation industry.

ACKNOWLEDGMENTS

The authors wish to thank Mr. K. Cook, Dr. H. Magid,

Mr. D. F. Orlowski, Ms. C. Beck, Mr. D. Konopa, Mr. L.

Bement and many others at AlliedSignal for their contributions to this paper. We also wish to thank Goldschmidt,

Osi, Demilec and AHAM for providing valuable data for

this paper.

REFERENCES

1. G. M. Knopeck, R. C. Parker, R. G. Richard, M. C.

Bogdan, "Update on the development of HFC-245fa as

a Liquid HFC Blowing Agent" Proceedings of The

Polyurethanes World Congress 1995 p.2

2. G. M. Knopeck, R. C. Parker, R. G. Richard and I. R.

Shankland, "Status Report on the Development of a

Liquid HFC Blowing Agent" Proceedings of The Polyurethanes World Congress 1994 p. 115

3. T. W. Bodnar, J. E. Dewhurst, J. J. Koch, T. R.

Demmin, R. E. Eibeck and R. C. Parker, "Minimization

of HCFC-141b Decomposition in Rigid Polyisocyanurate Foams" Proceedings of the Polyurethanes

1992 Conference p. 374

4. M. Bogdan, D. Orlowski, J. Bennington, J. Welch, "A

Method for the Determination of Cell Gas Content in

Polyurethane Foams" Proceedings of the Polyurethanes 1995 Conference p. 34

Bogdan, Williams, Logsdon, Parker 19

EE-RM-93-801 COMMENT 269

.. 

0 -

u 

III 

u. 

. .:II: 

.. 

HFC-24Sfa 

Temperature vs. k-Factor 

0.17,-------------:z----

0.16 

0.15 

0.14 -

0.13 

18.5 36.5 54.5 72.5 .90.5 

Mean Temperature of 

-0 days --1 day --7 days 

-28 days -- 56 days 

HCFC-141b 

Temperature vs. k-Factor 

0.18,-----------------

0.17 -..::------------..,.,...::;...----

S 0.16 r'"-c::::::------"==-..... ==-------::;:.".c:..---- u 

.:.::: ~ 0.15-t I_--------~::====::==~-------------

0.14 ~:=-====::::::::::::::::--"Ap~---

~ --=== 

0.13 -t-~~::::=:=;::::=:.-.----r__----, 

18.5 36.5 54.5 72.5 90.5 

Mean Temperature ° F 

--0 days --1 day --7 days 

-28 days -- 56 days 

Figure 5. Aging curves of foams produced with HFC-24Sfa and 

HCFC-141b 

Additional foaming evaluations have further defined 

the performance of HFC-245fa as a foam blowing agent. 

Foam aging experiments have shown that the k-factors of 

foams produced with HFC-245fa age at a slower rate than 

foams produced with HCFC-141b. In most cases, the thermal conductivity of HFC-245fa blown foams is superior to 

those of HCFC-141b blown foams after several weeks 

of aging as unfaced core samples. It has also been shown 

that the k-factor of HFC-245fa foams improve relative 

to the k-factors of HCFC-141b blown foams as the mean 

temperature decreases. In areas of low temperature 

applications it has been found that foams produced with 

HFC-245fa perform equivalently to those produced with 

CFC-ll. 

.. 

0 

-

u 

III 

u. 

. .:II: 

Handmix Data 

Temperature va. k-Factor at 56 Days 

0.17 t==== --------~----------

0 .. 16 

0.15 

0.14 

0.13 

18.5 36.5 54.5 72.5 90.5 

Mean Temperature ° F 

-CFC-11 SBA --HCFC-141b 

-HFC-245fa - Cyclopentane 

Figure 6. k-Factor VS. mean temperature for foams produced with 

HFC-245fa, HCFC-141b, and cyclopentane 

Although additional -Work is necessary on HFC-245fa 

before it is fully defined as a foam blowing agent, we 

believe that this compound will become the blowing agent 

of choice for the future. We are committed to the development and commercialization of HFC-245fa as the "third 

generation" blowing agent for the polyurethane and polyisocyanurate foam insulation industry. 

ACKNOWLEDGMENTS 

The authors wish to thank Mr. K. Cook, Dr. H. Magid, 

Mr. D. F. Orlowski, Ms. C. Beck, Mr. D. Konopa, Mr. L. 

Bement and many others at AlliedSignal for their contributions to this paper. We also wish to thank Goldschmidt, 

Osi, Demilec and AHAM for providing valuable data for 

this paper. 

REFERENCES 

1. G. M. Knopeck, R. C. Parker, R. G. Richard, M. C. 

Bogdan, "Update on the development of HFC-245fa as 

a Liquid HFC Blowing Agent" Proceedings of The 

Polyurethanes World Congress 1995 p.2 

2. G. M. Knopeck, R. C. Parker, R. G. Richard and 1. R. 

Shankland, "Status Report on the Development of a 

Liquid HFC Blowing Agent" Proceedings of The Polyurethanes World Congress 1994 p. 115 

3. T. W. Bodnar, J. E. Dewhurst, J. J. Koch, T. R. 

Demmin, R. E. Eibeck and R: C. Parker, "Minimization 

of HCFC-141b Decomposition in Rigid Polyisocyanurate Foams" Proceedings of the Polyurethanes 

1992 Conference p. 374 

4. M. Bogdan, D. Orlowski, J. Bennington, J. Welch, "A 

Method for the Determination of Cell Gas Content in 

Polyurethane Foams" Proceedings of the Polyurethanes 1995 Conference p. 34 

Bogdan, .Williams, Logsdon, Parker I 9 
r I3IOGR,APHIES

D. J. Williams

Dave Williams holds a B.S. degree

in Chemistry from The University

of New Haven, New Haven, CT,

USA. From 1975 to 1994, he

worked as a Research and Development Chemist and Technical

Service Representative for the

Upjohn Company and later The

Dow Chemical Company in a wide

variety of rigid polyurethane and

polystyrene foam application

areas. Dave joined AlliedSignal in

1994 and is currently the manager

of the Blowing Agent Technical

Service and Development Group

as well as the co-leader of the team

responsible for the commercialization of HFC-245fa at AlliedSignal's

Buffalo Research Laboratory. In

these capacities, he responsible for

technical' service and product

development of Allied-Signal's line

of CFC, HCFC, and HFC foam

blowing agents.

M.C. Bogdan

Mary Bogdan holds a B.S. degree

in Chemistry and an M.B.A. from

Canisius College. Since joining

AlliedSignal in 1989, she has been

involved in a variety of fluorocarbon and fluorine specialty research programs. She has been a

Group Leader in the Analytical

Services Group. Currently, Mrs.

Bogdan is a Senior Research

Chemist in the Genetron® Products Technical Service and

Applications group at AlliedSignal's Buffalo Research Laboratory.

She has global responsibility for

construction and systems applications.

P. B. Logsdon

Peter B. Logsdon received a B. S.

degree in Chemistry from SUNY

Brockport in 1986 and a M. S. in

Physical - Chemistry from the

University at Buffalo in 1989.

Since joining AlliedSignal in 1989,

he has been involved in the development of CFC replacements for

solvent, refrigerant, sterilant gas

and blowing agent applications.

Mr. Logsdon is currently a member of the Genetron® Blowing

Agent Technical Service and Applications Group and has global

responsibility for appliance, ex=

truded foam and integral skin

foam applications.

R.C. Parker

Robert C. Parker received a B.A.

in chemistry from Lake Forest

College in 1963 and a M.S. degree

in organic chemistry from West

Virginia University in 1967. He

joined AlliedSignal in 1989 and is

currently working in the Genetron® Products Technical Service

and Applications group at AlliedSignal's Buffalo Research Laboratory. He is a member of the team

responsible for the development

and commercialization of liquid

HFC foam blowing agents. "

10 / Bogdan, Williams, Logsdon, Parker

EE-RM-93-801 COMMENT 269

'/ BIOGRAPHIES 

fr-(! D.J. Williams 

Dave Williams holds a B.S. degree 

in Chemistry from The University 

of New Haven, New Haven CT 

USA. From 1975 to 1994, h~ worked as a Research and Development Chemist and Technical 

Service Representative for the 

Upjohn Company and later The 

Dow Chemical Company in a wide 

variety of rigid polyurethane and 

polystyrene foam application 

areas. Dave joined AlliedSignal in 

1994 and is currently the manager 

of the Blowing Agent Technical 

Service and Development Group 

as well as the co-leader of the team 

responsible for the commercialization ofHFC-245fa at AlliedSignal's 

Buffalo Research Laboratory. In 

these capacities, he responsible for 

technical se:rvice and product 

development of Allied-Signal's-line 

of CFC, HCFC, and HFC foam 

blowing agents. 

M.C.Bogdan 

Mary Bogdan holds a B.S. degree 

in Chemistry and an M.B.A. from 

Canisius College. Since joining 

AlliedSignal in 1989, she has been 

involved in a variety of fluorocarbon and fluorine specialty research programs. She has been a 

Group Leader in the Analytical 

Services Group. Currently, Mrs. 

Bogdan is a Senior Research 

Chemist in the Genetron® Products Technical Service and 

Applications group at AlliedSignal's Buffalo Research Laboratory. 

She has global responsibility for 

construction and systems applications. 

10 I Bogdan, Williams, Logsdon, Parker 

! P. B. Logsdon 

I Peter B. Logsdon received a B. S. 

: degree in Chemistry from SUNY 

Brockport in 1986 and a M. S. in 

Physical. Chemistry from the 

University at Buffalo in 1989. 

Since joining AlliedSignal in 1989, 

he has been involved iii the development of CFC replacements for 

solvent, refrigerant, sterilant gas 

and blowing agent applications. 

Mr. Logsdon is currently a member of the Genetron® Blowing 

Agent Technical Service and Applications Group and has global 

responsibility for appliance, exc 

truded foam and integral skin . 

foam applications. 

R.C. Parker 

Robert C. Parker received a B.A. 

in chemistry from Lake Forest 

College in 1963 and a M.S. degree 

in organic chemistry from West 

Virginia University in 1967. He 

joined AlliedSignal in 1989 and is 

eurrently working in the Genetron® Products Technical Service 

and Applications group at Allied· 

Signal's Buffalo Research Laboratory. He is a member of the team 

responsible for the development 

and commercialization of liquid 

HFC foam blowing agents ..