NASA Technical Memorandum 85876

NASA-TM-8587619840011407

fOB' REFEREl'lCE

Fire-Retardant Decorative Inks for

Aircraft Interiors

Zohar Nir, John A. Mikroyannidis, and

Demetrius A. Kourtides

February 1984

LISRARY COpy

LANGLEY RESEARCH CENTER

LIBRARY, NASA

HAMPTON, VIRGINIA

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National Aeronautics and

Space Administration

1 RN/NASA-TM-85876

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Fir~-retardant decorative inKs for atrcraft

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NASA Technical Memorandum 85876

Fire-Retardant Decorative Inks· for

Aircraft Interiors

Zohar Nir, Makhteshim, Ltd., Beersheba, Israel

John A. Mikroyannidis, University of Patras, Patras, Greece

Demetrius A. Kourtides, Ames Research Center, Moffett Field, California

NI\S/\

National Aeronautics and

Space Administration

Ames Research Center

Moffett Field. California 94035

FIRE-RETARDANT DECORATIVE INKS FOR AIRCRAFT INTERIORS

Zohar Nir,* John A. Mikroyan~idis,t and Demetrius A. Kourtides

Ames Research Center

SUMMARY.

Commercial and experimental fire retardants were screened for possible use with

acrylic printing inks on aircraft interior sandwich panels. The fire retardants were

selected according to their physical properties and thermostabi1ities. Thermostabi1ities were determined by the techniques of thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). A criterion was then established for selecting

the more stable agent. Results showed that some of the bromine-containing fire retardants are more thermostable than the acrylic ink, alone, used as a control. Also,

the bromine-containing fire retardants yield even better limiting oxygen index values

when tested after adding carboxy-terminated butadiene acrylonitrile (CT~N) rubber.

INTRODUCTION

In this study, candidates were screened to select fire-retardant additives for

the acrylic inks used on aircraft interior sandwich panels. These candidates were to

be additives that might not migrate (leach), such as reactive fire retardants, and

those polymeric fire retardants in which migration is diffusion-controlled.

The following criteria were set up for candidate selection:

1. Soluble in MEK (the acrylic ink solvent)

2. Thermostable

3. Has a potential reaction site, or a polymeric backbone

4. Contains halogens or phosphorus, or both

5. Able to be processed with the acrylic ink

6. Compatible with the curing cycle of the ink

The first two formulations in table 1 were selected from a variety of available viny1-

terminated fire retardants that met the above criteria.

The F2001P (no. 3, table 1), a commercial brominated fire retardant (ref. 1),

contains 50% Br. The family of these brominated polymeric additives (BPA) is available at various molecular weights ranging from 660 to 40,000. Chemically, the family

has two glycida1 groups, and includes aromatic bromine (which is very thermostable).

The BPA (F2001P) which was selected is soluble in MEK, and has an epoxy equivalent

(EE) of 545. This fire retardant was used as a control and a reference in a series

of formulations (nos. 4-7, table 1), in which different modifications of the basic

polymeric backbone.were .accomp1ished.

'/<Currently at Makhteshim, Ltd., Beersheba, Israel.

tCurrent1y at the University of Patras, Patras, Greece.
Recent research (ref. 2) showed that carboxy-terminated butadiene acrylonitrile

(CTBN) rubber improves the fracture toughnessof,various thermosets (refs. 3 and 4);

consequently, we wished to determine its effect on fire-retardant acrylic inks relative to a control.

In that research, rubber-toughened BPA (F200lP) was synthesized by reacting

F200lP with liquid CTBN rubber, using ethyltriphenyl phosphonium iodide (ETPPI) or

triphenyl phosphine (TPP) as a catalyst. This produced a concentration of prereacted

rubber in BPA (ref. 2). Molecules with concentrat,ions of up to 50% CTBN were synthesized to obtain a block'polymer of the general type shown in figure 1. Two of the

glycidyl groups were consumed, and the molecular weight increased accordingly. The

CTBN was now entrapped between two BPA units, thus retaining its elastomeric properties. The resulting block polymer still had two glycidyl ether groups.

The introduction of CTBN rubber decreases the bromine content of the BPA; therefore, modification with brominated phenols is requireq to keep an acceptable bromine

concentration. As a result, the two glycidyl end groups are further reacted with

brominated phenols, using the same catalyst, to produce a polymer that ,is capped at

both sides with the brominated phenoxy group (fig. 2). This procedure increases the

bromine content, the extent of the increase being dependent on the selected brominated phenol and the loaded amount of the CTBN rubber.

We used ~wo different models of brominated phenols:

pentabromophenol (PBP). In a typical modification (fig.

increased to 58% and 64% with no rubber (no. 4, table 1)

(no. 5, table 1).

tribromophenol (TBP) and

3), the bromine content was

and to 53% with 12% rubber

Model compounds were synthesized, with and without CTBN rubber. In both cases,

the F200lP was blocked through its dig1ycidy1 end groups with the brominated phenols

(fig. 3). The resulting products may serve as fire-retardant candidates, as well as

impact modifiers, for both fire-retardant thermoplastics and thermosets.

The incorporation of these fire retardants was technically successful. However,

in flame-spread tests, difficulties were encountered in evaluating the fire-retardant

properties of the fire-retardant-coated Tedlar sheets and the acrylic films made from

the acrylic ink.

MATERIALS

The following materials were used.

1. F2001P: brominated polymeric additive (BPA); epoxy equivalent (EE) 545;50%

bromine Content; mp 60°-70°C; Makhteshim Chemical Works, Israel.

2. Tribromopheno1(TBP): mp 95°-96°C; 72% Br; Great Lakes Chemical Corp.

3. Pentabromophenol (PBP): mp 229°-230°C; 82% Br; Great Lakes Chemical Corp.

4. Ethyl tripheny1 phosphonium iodide (ETPPI): Thibko1/Garstab Corp.

5. Carboxy-terminated butadiene acrylonitrile' (CTBN) rubber: Hycar 1300 x 13;

B. F. Goodrich Chemical Co.

2
6. 2,3 Dibromopropylacrylate (AE-59): Great Lakes Chemical Corp.

7. Bis(S-chlorethyl)vinyl phosphonate: Stauffer Chemical Co.

8. Acrylic ink: K. C. Coatings, Inc~

9. Tedlar: E. I. duPont de Nemours Co.

SYNTHESES

The various formulations (table 1) were calculated to contain the same loading

of 10% bromine, or an equivalent analog amount of combined chlorine and phosphorus

(no. 2, table 1). All formulations were adjusted to contain 60% w/v of solids as the

original formulation of the acrylic ink.

Synthesis of Tribromophenol-Blocked Polymer of the Brominated Polymeric

Additive (BPA): F200lP-TBP

A 2-liter resin kettle equipped with four standard inlets for nitrogen, mechanical stirrer, thermocouple, and chemicals loading was used as a standard reaction

vessel., A 1090-g (2-eq) sample of F200lP (brominated polymeric diglycidyl with

EE = 545) was introduced and heated until it was fully melted (70°-80°C). The temperature was then raised to 110°C, and 3.5 g (0.2%) of ethyl triphenyl phosphonium

iodide was added in one portion to the melted reaction mixture. Tribromophenol (TBP)

was then added in one portion, and the temperature in the reaction vessel fell to

90°C. The reaction continued at temperatures in the. range of 100°-120°C for 150 min.

The advancement of the reaction was monitored by titration to determine the acid

number (AN) value of the residual phenolic groups. Aliquotes of the melted reaction

mixture were taken every 40 min, dissolved in dioxane, and titrated with O.IN KOH/EtOH

using 1% alcoholic phenolphthalein as an indicator. At an AN of 0.75, the reaction

was stopped by pouring the vessel's contents into an aluminum pan. The product was a

glassy, amber, brittle solid. Its thermal properties are shown in no. 1, table 2.

Synthesis of Rubber-Toughened .Brominated Polymeric Additive Blocked

with TBP: F200lP-RTBP

The same equipment described in the preceding paragraph was used with the following materials.

1. F200lP, 1136.1 g (2.1 eq)

2. CTBN (Hycar1300 xU), 227.2 g (0.136 eq)

3. EtPhgP+I- (ETPPI), 2.7 g (0.2%) (first stage)

4. Tribromophenol (TBP) , 349.1 g (1.96 eq)

5. ETPPI, 1.3 g (0.2%) (second stage)

The CTBN (a high-viscosity liquid) was heated in the reaction vessel under nitrogen to 80°C, to reduce its viscosity. Afthat temperature, the F200lP was added as

3
fine powder. The mixture was heated to lOO°C while being stirred continuously until

fully homogenized.

The catalyst for the first stage was added, and the reaction was continued for

80 min. The reaction advancement was monitored by O.lN KOH/EtOH titration to determine the equivalent per hundred grams (EPHR) of the residual carboxy group. The reaction continued until the EPHR-COOH (fig. 1) had reached at least 0.0012 (2% of the

original EPHR).

Tribromophenol (TBP) was added in one portion, at temperatures in the range of

135°-140°C. TBP should be introduced carefully because it is subject to sublimation.

An additional portion 9f the catalyst (ETPPI) was later added. Reaction time was

2 hr, and the temperature reached l50°C.

The reaction was terminated, after an acid number (AN) <1.0 was reached, by

pouring the product into an aluminum pan. The product was a transparent, amber,

brittle solid. Its thermal properties are shown in no. 2, table 2.

Synthesis of Pentabromophenol (PBP) blocked polymer of Brominated

Polymeric Additive: F200lP-PBP

The same equipment previou!;'ly described was used with the following materials:

F200lP, 981 g (1.8 eq); PBP, 880.g (1.8 eq); and ETPPI, 2.79 g (0.15%)~ F2001P was

introduced first, and heated until fully melted. At 110°C, small portions of PBP

were introduced over a period of 10-15 min; temperature in the reaction vessel fell

to 100°C.

The reaction,was continued for 100 min, during which time the temperature was

elevated to 170°C. The reaction was monitored by titration, as previously described.

At an AN of <1.0 the reaction was stopped by pouring the product into an aluminum

pan. The product was a transparent, amber, brittle solid. Its thermal properties

are shown in no. 3, table 2.

Treatment of Synthesis Products

The above three products were brittle solids, and were treated separately as

follows in order to reduce the particle size. The size reduction was accomplished by

a ball mill, in the presence of 2% silica gel as a free-flowing agent. After the

milling, the product became a free-flowing powder that showed no tendency to cake.

If the reduction process was attempted without the anticaking agent, there was substantial caking, and the product stuck to the ball mill porcelain walls. Later on,

it was discovered that the presence of the 2% fumed silica particles facilitates the

phenomenon of afterglowing. Afterglowing is observed in flammability tests of specimens of the newly developed fire retardants in various thermoplastics.

In a different particle reduction process, the solid product was broken into

smaller lumps which were hammer-milled to give a fine, powdery product. No caking

was observed during the milling.

The yields of the syntheses were almost quantitative in the three products -

F200lP-TBP, F200lP-RTBP, F2001P:-PBP - although.some difficulties were experienced in

quantitatively taking the melted. viscous product out of the reaction vessel. The

4
product was fully soluble in common organic solvents such as MEK, toluene, and

dioxane.

FILM PREPARATION

Glass Plates

Films of acrylic ink, each containing a different fire-retardant additive, were

cast on glass plates. At first the solvent was vacuum evaporated, and the films

were then cured at 80°-100°C for 30 min in an air-draft oven.

The incorporation of the fire-retardant additives into the acrylic ink did not

significantly affect the transparency of the casting films. However, as a result of

adding the fire-retardant agent to the acrylic ink, some difficulties were experienced

in preparing the casting films. In particular the casting films from the F2001P-RTPB,

in both concentrations of CTBN rubber (nos. 5 and 7, table 1), adhered very tightly

to the glass plates. (The films could not be peeled off without being destroyed.)

In both cases, spraying the glass plates with a mold-release dry lubricant helped

separate the ink films from the plates, but also reduced the films' transparency:

Film no. 7 in table 1 was observed to be relatively brittle. After the inks were

peeled off the plates, the thermochemical properties of the inks were examined by

thermogravimetric analysis (TGA) , and by differential scanning calorimetry (DSC).

Polyvinyl Fluoride (Ted1ar) Sheets

By the same method used to prepare the glass plates, sheets of polyvinyl fluoride

were covered by films of fire-retardant acrylic inks. Later, because no useful

results were obtained by flame spread tests, the Ted1ar sheets' flammability was

evaluated by determining the limiting oxygen index (LOI) at room temperature (ref. 5).

The smoke emission of the Ted1ar films was also determined later.

THERMOCHEMICAL MEASUREMENTS

Thermogravimetric Analysis and Differential Scanning Calorimetry

Thermogravimetric analysis (fig. 4) and differential scanning calorimetry

(fig. 5) techniques were used to evaluate relative thermostability of fire retardant

formulations. These formulations were compared with an "as received" acrylic ink as

a control. For ease of comparison, one should follow the line showing the acrylic

ink control specimen.

Thermogravimetric analysis (TGA) was accomplished by using a du Pont 951 TGA

cell and 1090 thermoana1yzer. Heating rates were 20°C/min, and the N2 flow rate was

80 m1/min. On figure 4, the control starts to lose weight at 120°C, until the deflection point at 240°C. There, the specimens start to lose weight rapidly - 40% during

a temperature interval of 40°C. These curves show that at temperatures above 120°C

and below 240°C, these substances would contribute toxic gases; that is, in an actual

fire situation, the observed weight loss would convert to a net contribution to the

toxic gases. Figure 4 indicates that, in the 120°-240°C range, all the fire-retardant

samples lose less weight (therefore are more stable) than the control (sample no. 0).

5
The order of observed thermal stabilities, therefore, was established in descending order as shown on table 3. This relative order of stabilities shows the advantage

of aromatic bromine versus aliphatic bromine, as observed by comparing F2001P derivatives and 2,3 dibromopropy1 acrylate. The comparison of aromatic bromine with a

combination of chlorine and phosphorus also favors the aromatic bromine.

In the differential scanning analysis (DSe) studies, the first thermal transformation for the acrylic ink occurs at 51°-52°e,' as shown in figure 5. All formulations

show a decomposition exotherm in the range of 2l0o~220oe, which is probably accompanied by the unzipping of the acrylic chain. The information gained from the Dse

studies is, therefore, insufficient as a basis for judging the relative stability of

the fire-retardant formulations.

Limiting Oxygen' Index and Smoke Emission Tests

FAR 25-32 flame-spread tests (ref. 6) were used to evaluate the flammability

properties of the polyvinyl fluoride sheets which were coated with fire-retardant

acrylic inks. No useful results were obtained, however, because the sheets melted

when the specimens were exposed to the flame. Different char lengths were obtaiped

using the same material.

The flame-spread test according to the ASTM E162 test method (ref. 7) was also

attempted. Again, the results were neither satisfactory nor reproducible. As soon

as the flame started at the top, the polyvinyl fluoride sheet, coated with a fireretardant acrylic ink, burned and contracted away from the flame source within a

few seconds.

Because both of these flame-spread tests were ineffective for determining flammability, the limiting oxygen index (LOI) test was performed, and the established

order of efficiency is shown in table 4.

In the order of efficiency, which differs from the order of thermal stability

(table 3), the aliphatic bromine (with an LOI value of 31.2) is inferior relative to

the chlorine and phosphorus combination. Only the F200lP has a lower LOI, namely,

30.2.

The smoke-emission characteristics of the candidate materials were determined

by using the technique of smoke accumulation in an enclosure, and by testing the

materials in the smoke density chamber (ref. 8). The apparatus was operated over a

range of incident heat fluxes, 1.0 to 2.5 W/cm2 , to determine the response of the

inks to various fire environments. The results are shown in table 5.

Stability of Fire Retardant Agents

The derivatives of F200lP show higher LOIs than the baseline acrylic ink.

Remarkably, the higher the rubber content, the higher the LOI, the aliphatic chains

of the CTBN rubber being'potentia1 reaction sites for the acrylic ink. This phenomenon was given further attention by doing TCA studies of the fire-retardant

agents themselves (fig. 6). In this figure,it is apparent that the rubber-containing

F200lP is less stable than either of the bromopheno1s-b10cked F200lP, and the TBPblocked F200lP is more stable than the PBP-blocked F200lP. CTBN rubber (as received)

is very stable in comparison with the other three tested.

6
Thermostability correlated well with the LOI values - the less stable the aromatic bromine, the higher the LOI. It is'1:i.ke'ly that higher rubber concentrations

would result in less stable polymers and would tend to supply more bromine to the

flame zone. The aliphatic fire retardants are less stable and, therefore, do perform

better than F2001p'itself, which is more stabieihan its derivatives.

When theTGAresu1ts and the LOI results are compared, the following order in

terms of fire-retardant effectiveness is established:

F2001P-RTBP (16% CTBN) > F200IP-PBP > F200IP-RTBP (12% CTBN)

The thermostabilities of other flame retardants do not compare favorably with that of

the fire-retardant ink.

Further evaluation of mechanical and other properties of the ink (peel strength,

ultraviolet res'istivity, etc.) should be performed to determine the preferred fireretardant formulation.

CONCLUSIONS

The fire resistance of the acrylic ink was enhanced by the use of the fire

retardants. It was found that a modified brominated polymeric additive results in

a more stable fire-retardant formulation. The fire-retardant acrylic-ink formulations are more thermally stable than the control, and higher by 4.3-4.9 limiting

oxygeriindex units than the control.

It was also shown that the thermostabi1ity of a fire-retardant agent correlates

with its LOI performance. Because this phenomenon is typical of certain polymers,

an especially made formulation should be carefully adjusted to the polymer under

investigation.

7
REFERENCES

1. Nir, Z.; Gilwee, W. J.; Kourtides', P. A.; and Parker, J. A.: Rubber-Toughened

Polyfunctional Epoxies: Brominated vs. Nonbrominated Formulations for

Graphite Composites. 38th Annual Conference, Reinforced Plastics Composites

Institute, The Society of the Plastic Industry, Inc., Paper 16B, Feb. 7-11,

1983, pp. 1-6. '.

2. Nir, Z.; Gilwee, W. J.; Kourtides, D. A.; and Parker, J. A.: Rubber-Toughened

Polyfunctional Epoxies: Different Molecular. Weights of Rubber-Modified

Brominated Epoxies for Graphite Composites. 41st Annual Technical Meeting

(ANTEC) of the SPE, Chicago, Ill., May 2-5, 1983.

3. Drake, H.; and Siebert, R. A.: Elastomer Modified Epoxy Resins for Structural

Application. SAMPE Quarterly, vol. 6, no. 4, 1975.

4. Rowe, E. H.; and Siebert, A. R.: Rubber Toughened Thermoset. CIR Review,

Advances in Chemistry Series 154, ACS, Washington, D.C., 1976 pp.326-346.

5. ASTM Standard Test Method for Measuring the Minimum Oxygen

port Candle-Like Combustion of Plastics (Oxygen Index).

Society for Testing and Materials, Philadelphia, Penn. :. ,

Concentration to SupD2863, American

6. Federal Aviation Regulation, Vol. III, Part 25, Amendment 25-32, Paragraph 25.853,

Fire Protect'ion - Compartment Interiors. Federal Aviation Administration,

effective May 1, 1972.

7. ASTM Standard Test Method for Surface Flammability of Matedals Using a Radiant

Heat Energy Source. El62, American Society for Testing and Materials,

Philadelphia, Penn.

8. ASTM Standard Test Method for Specific Optical Density of Smoke Generated by

Solid Materials. E662, American Society for Testing and Materials,

Philadelphia, Penn.

8
TABLE 1.- FORMULATION OF FIRE RETARDANTS IN MEK CALCULATED FOR 100 ml INK

(60% SOLUTION w/v lNMEK) ....

Sample % hydrogen, FR per 100 cms Dilutinga % Br, (C1) ,

No. Sample description C1, P, or ink MEK, MEK, cms and (P) CTBNrubber g

1 2,3 Dlbromopropy1 58.8 Br 12.3 15.3 10.0

acrylate

2 Bis(S=ch1oroethy1)vinyl 13.3 P 22.5 28.1 5.0 (P)

phosphonate 30.0 C1 11.2 (C1)

3 Brominated polymeric 50.0 Br 15.0 18.7 10.0

additive (F2001P)

4 F2001P-Tribromopheno1 58.0 Br 12.5 15.6 10.0

(TBP)

5 F2001P-Rubberized 53.0 Br 13.9 17.4 10.0

tribro~opheno1 +12.0 CTBN

(RTBP)

6 F2001P-Pentabromopheno1 63.0 Br 11.3 18.8c 10.0

(PBP)

7 F2001P-Rubberized 48.6 Br 20.5 34.3 10.0

tribromopheno1 16.2 CTBN

(RTBP)d ,

bFinal ink concentration 60.0% w/v.

CTBN rubber content 12.0%.

c50 :50 dioxane:MEK.

dCTBN rubber content 16.2%.

TABLE 2.- THERMOGRAVIMETRIC (TGA) AND DIFFERENTIAL SCANNING CALORIMETRY (DSC)

CHARACTERIZATION OF REACTION PRODUCTS

MP TGA (Nz 80 m1/min, 20°C/min)

Product Br, % DSC, Onset, Inflection, Completion, Char yield, °C °c °c °c %

(1) F2001P-TBP 58.0 80-81 369.7 391.9 413.0 10.4

(2) F200lP-RTBP 53.5 65-68 353.4 376.5 395.3 21.8

(3) F2001P-PBP 64.0 80 286.6 317.2 361.7 14.5

9
TABLE 3.- OBSERVEDTHE~ STABILITIES

Order of thermal Sample Sample description stability No.

1 3 Brominated polymeric additive (F2001P)

2 5 F2001P - Rubberized tribromopheno1 (RTBP, 12.0% rubber)

3 7 F2001P - Rubberized tribromophenol (RTBP, 16.2% rubber)

4 4 F2001P - Tribromopheno1, (TBP)

5 6 F2001P - Pentabromophenol (PBP)

6 2 Bis(S-chloroethyl)vinyl phosphonate,

7 1 2,3 Dibromopropyl acrylate

8 0 Acrylic ink

TABLE 4.- LIMITING OXYGEN INDEX (LOI) OF FIRE-RETARDANT INK (1-7)

VERSUS CONTROL (0)

Sample No. Sample description LOI value to LOla

0 Acrylic ink (neat) 28.4 0

1 2,3 Dibromopropyl acrylate 31.2 2.8

2 Bis(S-chloroethyl)vinyl phosphonate 32.3 3.9

3 F2001P 30.2 1.8

4 F2001P-TBP 31. 3 2.9

5 F200lP-RTBpb 32.7 4.3

6 F200lP-PBP 33.0 4.6

7 F200lP-RTBpc 33.3 4.9

~percent difference with respect to sample O.

CTBNrubber content 12.0%.

cCTBN rubber content 16.2%.

TABLE 5.- SMOKE DENSITY OF FIRE-RETARDANT INK (1,2,3,5) VERSUS CONTROL (0)

Sample 1 W/cm2 2.5W/cm2

No. Sample description

Ds-2 min Dm Ds-2 min Dm

0 Acrylic ink (neat) 1.54 2.61 1.90 2.86

1 2,3 Dibromopropy1 acrylate 1.96 8.44 3.52 8.98

2 Bis(S-ch1oroethy1)viny1 phosphonate 0.38 0.90 6.75 8.25

3 F200lP 0.41 0.51 5.38 5.83

5 F200lP-RTBpa 0.91 1.04 6.14 6.34

aCTBN (rubber content 12.0%).

10
a

/\ IBPA I

a

/ \ + HOOCfCHrCH-CH-CH2}X-(CH2-1Htv-] caOH

c=N Z

BROMINATED POLVMERIC

ADDITIVE

j

CARBOXV-TERMINATED BUTADIENE

ACRVLONITRILE (CTBN) RUBBER

ETHYL TRIPHENYL PHOSPHONIUM

IODIDE (ETPPI)

BPA-CTBN-BPA TYPE REACTION PRODUCT

Figure 1.- Synthesis of rubber-toughened BPA.

(1) BROMINATED PHENOLS:

(2) ETPPt (0.15%)

o

1\ IBPA H CTBN HBPA I o

1\

OH

Q

n = 3, 5

OH

?-o~ BPA HCTBN

I

Brn

OH

HBPA~O~

Figure 2.- Synthesis of rubber-toughened, brominated phenols-blocked BPA.

11
o 0

1\ I BPA I 1\

Br =50%

Brn n = 3. 5

(2) ETPPI (0.15%)

Brn OH· OH Brn

Q-O-Y BPA P-O--Q

BROMINATED PHENOL BLOCKED BPAj

n =3 Br 58%

n::; 5 Br 64%

Figure 3.- Synthesis scheme of brominated phenols-blocked BPA.

12
320 360 400 440

o ACRYLIC INK

1 ~3 DIBROMOP_ROPYL ACRYLATE

2 BIS i!3-CHLOROETHYL) VINYL PHOSPHONATE

3 BROMINATED POLYMERIC ADDITIVE (F2001P)

4 F2001P-TRIBROMOPHENOL (TBP)

5 F2001P-RUBBERIZED-TBP (RTBP, 12% RUBBER)

6 F2001P-PENTABROMOPHENOL (PBP)

7 F2001P- RUBBERIZED TRIBROMOPHENOL

(RTBP, 16.2% RUBBER)

60

......--~._ 3 ;.:. -~~.. --.-.-..... ~.::-- . ctCl.:-_" - .•

~~:",----~,\ ....~~.. \\'-..

~.ii<'\\

~~6~~..

\.\ ..~~~\. \ .. \\ \ \ /, . \ . INK \" \ .~ \\.. .\' \

'\\.,,,\s··\. 7 . \ .

\""

\\' \\ \ \\\. .--- 5

\ '.~."-- 4

\ '\'-l

\

\2

50 L.-.__--L --'--__---.;L.-.__--L -l.-__----.JL.-__--U_\...:.....-_--L -L. .l.--__-----I

o 40 80 120 160 200 240 280

TEMPERATURE,oC

80

70

90

100

110

120

...

c: _(I)

u ,-~

-(I)

a.

lI

(:J

w

.-.

w s:

Figure 4.- Thermogravimetric analysis of fire-retardant acrylic ink films (Nos. 1~7)

versus control (0): nitrogen flow rate 80 ml/min; heating rate 20°C/min.
'.

".

....

..........

-4

-5

-8

-9

-3

o ACRYLIC INK

1 2

r DIBROMOPROPYL ACRYLATE

2 SIS ({3-CHLOROETHYL) VINYL PHOSPHONATE

3 BROMINATED POLYMERIC ADDITIVE (F2001P)

4 F-2001P-TRIBROMOPHENOL (TBP)

-- 5 F2001p·HTBP (12% RUBBER) \

. 3 6 F2001 P-PENTABROMOPHENOL (PBP) \'-.- r" '", _..- 7 F2001p:RTBP (16.2% RUBBER)

\'~ \ . ,~ ·<r~:--=.~_ ,'\ ./ :,.l\ ',''\., ""--.~.:. ::::-"'_-. . ,";n' .

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: \ '\ ....- - - - - --- - / \,', J'~.::' \; ~'. \2/ --__ /

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. 7 / "-"_ -1111 '. ',-., "--. -...... - /' ::\I'.j f

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-1 0 L- .L- .L- .L-~--..L----.L----.L-----'---~~<--..--.LL.-----L-----L-L----' '~I 20 40 60 80 '100 120 140 160 180 . 200 220 240

TEMPERATURE,oC

-6

5:

o

...J

LL

-7

w

J:

Figure 5.- Differential scanning analysis of fire-retardant acrylic ink films

(Nos. 1-7) versus control (0): nitrogen flow rate 80 ml/min; heating rate

20 o e/min.
120

80

lI 60 C)

w

$ F2001P-TBP

f-'

\Jl F2001P-RTBP

40 F2001P-PBP

_.- CTBN RUBBER

"'--- .......-- --~--- . -----

__.-fi-lii-iii-iii-.-iili-iiili-.-iiiiiflliiiliiiftiiiiiiliiiiiiii-.-.-iiiiiil-iii-ifi-_l'!:!Iilfti-==-~-~._== _ .... ._,_.J CTBN RUBBE R

....." '--.............

'\ ""

\ '\ ".

\ \ '\ \ "

\

\

\-- F2001 P-TBP

H---4---

,

F2001-RTBP n- F2001 P-PBP

\ \

\ '

20

100

o 40 80 120 160 200 240 280

TEMPERATURE, "c

320 360 400 440

Figure 6.- Thermogravimetric analysis in nitrogen atmosphere of modified BPAs -

F200lP-TBP; F200lP-RTBP; F200lP-PBP - versus CTBN rubber: nitrogen flow rate

80 ml/min; heating rate 20°C/min.
1

1. Report No. 2. Government Accession No. 3. Recipient's Catalog No.

NASA .TM-85876

4. Title and Subtitle 5. Report Date

FIRE-RETARDANT DECORATIVE INKS FOR AIRCRAFT February 1984

INTERIORS 6. Performing Organization Code

7. Author(s) Z. Nir (Makhteshim, Ltd. , Beersheba,Israe1), 8. Performing Organization Report No.

J. A. Mikroyannidis (Univ. of Patras, Patras, Greece) A-9597

and D. A. Kourtides 10. Work Unit No.

9. Performing Organization Name and Address T-4319

NASA Ames Research Center 11. COntract or Grant No.

Moffett Field, CA 94035

13. Type of Report and Period Covered

12. Sponsoring Agency Name and Address Technical Memorandum

National Aeronautics and Space Administration 14. Sponsoring Agency Code

Washington, DC 20546 505-45-11

15. Supplementary Notes

Point of Contact: D. A. Kourtides, Ames Research Certter, MS 223-6, Moffett

Field, CA 94035 FTS 448-5226 or (415) 965-5226

16. Abstract

Commercial and experimental fire retardants were screened for possible

use with acrylic printing inks on aircraft interior sandwich panels. The

fire retardants were selected according to their physical properties and

thermostabilities. Thermostabi1ities were determined'by the techniques of

thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) .

A criterion was then established for selecting the more stable agent.

Results showed that some of the bromine-containing fire retardants are more

thermostable than the acrylic ink, alone, used as a control. Also, the

bromine-containing fire retardants yield even better limiting oxygen index

values when tested after adding carboxy-terminated butadiene acrylonitrile

(CTBN) rubber.

.,'.

17. Key Words (Suggested by Author(s)) 18. Distribution Statement

Inks Unlimited

Fire retardants

Coatings

Subject Category - 23

19. Security Classif. (of this report) 20. Security Classif. (of this page) 21. No. of Pages 22. Price"

Unclassified Unclassified 17 A02

"For sale by the National Technicellnformetion Service, Springfield, Virginia 22161