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The Effects of E20 on Plastic Automotive Fuel 

System Components 

 Bruce Jones, Gary Mead and Paul Steevens 

 Minnesota Center for Automotive Research 

at Minnesota State University, Mankato

ABSTRACT 

The focus of this study was to compare the effects of 

E20 versus E10 and gasoline on plastic materials found 

in automotive and small engine fuel system components. 

Plastic samples were prepared using SAE and ASTM 

standards and exposed to blends of ASTM Fuel C; 90% 

Fuel C and 10% aggressive ethanol (E10); and 80% 

Fuel C with 20% aggressive ethanol (E20) at an 

elevated temperature of 55 °C for 3024 hours. The fuel 

was changed in weekly intervals for the 18-week study. 

INTRODUCTION 

Minnesota Governor Tim Pawlenty signed a bill on May 

10, 2005 that requires by volume 20% of the fuel sold in 

Minnesota to be ethanol. Currently, gasoline sold in 

Minnesota contains 10% ethanol (E10) by volume. 

Ethanol, C2H5OH, is an alcohol that can be derived from 

starches such as corn or materials containing sugars 

such as sugar cane. Ethanol can also be made from 

cellulosic materials such as grasses by converting them 

into sugars. However, this process is much more cost 

intensive and has not yet reached commercial 

production levels. Ethanol is considered a renewable 

fuel and is also classified as an alternative fuel since it 

can be used as a substitute for gasoline. 

The passage of the law is only the first step. The fuel 

may not be used on public roadways until a federal 

section 211f waiver is obtained from the United States 

Environmental Protection Agency (EPA). Extensive 

testing in five areas: vehicle driveability, vehicle 

emission control system effectiveness and durability, 

vehicle tailpipe and evaporative emissions, fuel system 

material compatibility, and public health must be 

conducted in order to obtain the waiver (C. Jewitt, 

personal communication, July 6, 2005). This will be a 

costly and timely process requiring many different 

studies. 

This paper represents one in a series of four papers that 

focus on the effects of 20% ethanol-blended fuel (E20) 

on fuel system components. This paper provides some 

of the background information on E20 and the various 

laws that affect its use as an on-road fuel. Next, it 

contains a brief review of literature on E20 with a 

particular focus on material compatibility issues. Finally, 

it investigates the issues of designing the material 

compatibility study in terms of standards, procedures, 

and equipment needed to carry out the testing. 

MINNESOTA ETHANOL LEGISLATION 

On May 10, 2005, Minnesota Governor Tim Pawlenty 

signed into law a bill requiring ethanol to constitute 20% 

of the gasoline sold in the State of Minnesota. The bill 

allows for two methods of achieving this. First, if by 

December 31, 2010 the volume of ethanol sold in the 

State through the combination of E10 and E85 reaches 

20% of the total gasoline sold in the State, then the goal 

will be met and there will not be any changes in the fuel 

sold. If the combination of the two fuels’ ethanol content 

does not reach at least 20% of the total fuel sold, then 

by August 30, 2013 the ethanol content of gasoline will 

be increased from 10% to 20% by volume (Eisenthal, 

2005). 

The second method, 20% ethanol in all gasoline, 

requires the EPA to approve a waiver for the use of E20. 

EPA waivers can be granted in one of two ways. The 

EPA can review the application and supporting data and 

grant the waiver. Or, if the EPA fails to provide a 

decision on the waiver within 180 days, the waiver is 

automatically granted. This clause is of particular 

concern because the original fuel waiver for E10 was 

granted because the EPA failed to make a decision in 

180 days. The Minnesota law explicitly states that the 

failure of the EPA to act shall not be deemed an 

approval. 

LITERATURE REVIEW 

The passage of the Minnesota E20 legislation raised 

many questions about the effects of E20 on non-flex fuel 

vehicles. All vehicles sold in the United States since the 

early 1980s are compatible with E10, but whether or not 

they are compatible with E20 is not known. Before E20 

can be sold in Minnesota, a section 211f waiver needs to 

be obtained from the United States Environmental 

Protection Agency (EPA). In order to obtain a waiver, 

extensive research and testing will need to be conducted 

in five areas: drivability, fuel system material 

compatibility, tailpipe and evaporative emissions, 

emission control system effectiveness and durability, 
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and health effects. This research and testing will be 

conducted to ensure that the fuel does not cause any 

more problems than gasoline in the five categories. 

The fuel systems on vehicles produced today are seeing 

an ever-increasing amount of ethanol-blended fuels and 

are expected to have a usable lifespan of 15 to 20 years. 

Currently, all fuel systems are compatible with E10, but 

as increased ethanol blends become more prevalent, 

the need to quantify the effects of higher blends on 

materials is necessary. Unfortunately, there is little 

information on the non-linear effects of increased 

ethanol blends on fuel system materials. This means 

that as the concentration of ethanol increases from 0 to 

100% there is no model that accurately predicts the 

effects on materials. In fact, neat ethanol and neat 

gasoline often have a smaller negative impact on 

materials than gasoline-ethanol blends. To compound 

this problem, mid-range blends of 15 to 50%, often have 

the largest negative impact on materials. 

The MSU material compatibility study started out like 

most research with a comprehensive review of the 

literature. To guide this review, a few questions were 

asked: (a) What literature exists on E20 and materials? 

(b) What materials are in a fuel system? (c) What 

standard test procedures are used to validate a material 

for compatibility with a fuel? (d) By what criteria is a 

material deemed compatible or incompatible with a fuel? 

With these questions in mind, a thorough review of the 

Society of Automotive Engineers’ (SAE) technical paper 

library was conducted along with an extensive internet 

search. Also, Original Equipment Manufacturers 

(OEMs), Tier I and II suppliers (supply parts to the 

OEMs), and material testing laboratories were contacted 

for information. 

Throughout the search for information on E20, it became 

apparent that there was very little information publicly 

available. Most OEMs have tested with a fuel close to 

E20, such as E25 because of its extensive use in Brazil, 

but retain this information as proprietary. Several small 

material studies mentioned E20 or tested a blend close 

to E20 such as E25, but these studies offered only a 

small portion of the information that would be necessary 

for a waiver. In fact, only one major study on E20 was 

found, the Orbital Engine Company’s study for the 

Commonwealth Government of Australia conducted 

from October 2002 through March 2003 (Orbital, March 

2003, and May 2003). 

The Orbital study was extremely comprehensive, 

covering both automobiles and small engines in areas of 

emissions, drivability, material compatibility, durability, 

and a well-to-wheel study. With regards to material 

compatibility, the Orbital study tested actual components 

from vehicles. The study found that E20 caused 

significant problems with many metal, plastic, and rubber 

components that gasoline did not. The Orbital study was 

carefully reviewed at MSU. The study identified 

significantly higher levels of discoloration and tarnishing 

on components exposed to the E20 than the gasoline 

reference fuels in the study. However, it should be 

noted that E10 was not included in this study and other 

research studies have noted similar discoloration and 

tarnishing associated with the use of E10. Also, it is 

believed that corrosive water was added to the E20 

blends at levels high enough to cause phase separation 

but was not added to the gasoline reference fuels. 

According to SAE recommended practice J1681 

Gasoline, alcohol and diesel fuel surrogates for 

materials testing, corrosive water is only added to 

gasoline or ASTM Fuel C, not ethanol (SAE, 2000). This 

test method could be a reason for the extreme negative 

results that the Orbital study reported. 

FORMULATING EXPERMIENTS 

With a lack of available literature on E20 using testing 

procedures outlined by the Society of Automotive 

Engineers (SAE) or the American Society for Testing 

and Materials (ASTM), it became apparent that actual 

material compatibility experiments would be necessary 

to answer some of the questions about the effects of 

20% ethanol blends. It was also determined that E10 

should be included in any material compatibility tests as 

a reference to the changes caused by ethanol. Ethanol 

does cause different changes to materials than gasoline. 

But, if E20 did not cause a larger negative impact on 

materials than E10, an accepted motor fuel, then E20 

would be acceptable. The inclusion of E10 in the testing 

for the purpose of differentiating acceptable changes 

caused by ethanol is a significant component of the 

MSU material studies. 

 

PROCESS OVERVIEW 

The procedures for the plastics testing were developed 

from six main standards: SAE J1748 Methods for 

determining physical properties of polymeric materials 

exposed to gasoline/oxygenate fuel mixtures; SAE 

J1681 Gasoline, alcohol, and diesel fuel surrogates for 

material testing; ASTM D618-00 Standard practice for 

conditioning plastics for testing; ASTM D543-95 

Standard practice for evaluating the resistance of 

plastics to chemical reagents; ASTM D638-03 Standard 

test method for tensile properties of plastics; and ASTM 

D256 Standard Test methods for determining the Izod 

pendulum impact resistance of plastics (SAE, 1998, 

2000; ASTM, 2000, 1995, 2003, 2006). SAE J1748 was 

the overarching standard that provided modifications to 

ASTM D543 to tailor the procedures for ethanol-blended 

fuels testing. After formulating the test procedures to 

reflect specific equipment and resources, the procedures 
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were forwarded for peer review and altered according to 

expert suggestions. 

All testing and data collection took place in a room 

equipped with a ventilation system designed to handle 

hazardous fumes. All samples were prepared as 

specified by ASTM D618-00, Standard practice for 

conditioning plastics for testing. After the samples were 

prepared, the weights and dimensions were measured 

to provide a baseline for comparison. Photographs of 

the color and surface texture were also taken. 

As per SAE J1748 and ASTM D543, specimens were 

completely immersed for 3,024 hours at 55 ± 2 °C before 

testing. The following properties were measured before 

and after immersion: volume, weight, appearance, 

impact resistance, tensile strength, and ultimate 

elongation. 

The plastics testing required three different shaped test 

specimens. The first was a 2 in. diameter by 0.125 in. 

thick disk. This specimen shape was used for volume, 

weight, and appearance change measurements. It will 

be referred to as the appearance specimen. Five 

appearance specimens of each material were immersed 

in each fuel. The second specimen shape prepared and 

immersed was a Type 1 tensile dumbbell as specified by 

ASTM D638 (2003). These samples were used for 

tensile strength and elongation measurements. They will 

be referred to as the tensile specimens. Five tensile 

specimens of each material were prepared and 

immersed in each test fuel. In addition, five specimens 

of each plastic were prepared but not exposed to the 

test fuels. These pieces served as control samples to 

identify any physical changes that occurred over the 

testing period that were not caused by any of the test 

fuels. The third specimens used were Izod-type 

specimens as specified by ASTM D256. They were used 

for impact testing (2006). A total of forty Izod specimens 

were prepared from each material. Ten samples were 

placed in each of the test fuels and ten pieces were 

used as control samples. 

All of the specimens were conditioned in accordance 

with ASTM D618 Procedure A (2000). This is very 

important because temperature and humidity can affect 

some plastics. After conditioning, the specimens were 

weighed to ± 0.0001 g and measured to ± 0.001 in. as 

specified by ASTM D543 (1995). Photographs were also 

taken at this time to show color and surface texture of 

the specimens. Once the physical data was recorded, 

the specimens were suspended in sealed glass jars 

containing the appropriate test fluids: C, C(E10)A, and 

C(E20)A. The samples were completely submerged in 

the test fluids during the immersion process. The jars 

were then placed in an oven at an elevated temperature 

of 55 ± 2 °C. The test fluid was changed weekly and any 

changes in color were noted. 

 

After the 3,024 hour immersion time, the jars were 

removed and allowed to cool for 24 hours. Each 

specimen was dimensionally measured, weighed, and 

photographed for appearance. The immersed and nonimmersed tensile specimens were tested in accordance 

with ASTM D618 to measure tensile strength and 

elongation (2000). Finally, impact testing following 

ASTM D256 was conducted on all test samples to 

determine impact resistance (2006). See Appendix A for 

the complete test procedure. 

MATERIALS 

Raw materials used in the construction of fuel system 

components were tested instead of actual components. 

Testing raw materials allows for much broader coverage 

than testing individual components. For instance, the 

results from a test on selected plastic could provide 

information regarding the material’s performance in a 

variety of components manufactured by any 

manufacturer using that material. This was determined 

to be more practical than testing individual components. 

In addition, many of the industry-accepted standard test 

procedures require specimens of specific dimensions 

that would be difficult to obtain from actual components. 

The list of materials used in the fuel systems of 

automobiles from the 1970’s forward, marine engines, 

non-road engines, and fuel dispensing equipment is 

immense. It would be virtually impossible for one study 

to test every material and combination of materials used. 

The materials list for this study was created from various 

sources such as literature reviews, manuals, and 

recommendations from fuel system and engine 

manufacturers. After the list of plastics was assembled, 

it was forwarded to a list of fuel-system engineers from 

several OEMs and Tier I and II suppliers for peer review. 

Finally, materials that are commonly used in flex-fuel 

vehicle fuel systems were removed from the list because 

they have already been proven compatible with any 

blend of ethanol from 0 to 85%. The eight materials 

included in the study are listed below. 

• acrylonitrile butadiene styrene (ABS) 

• polyamide 6 (PA 6) [Nylon 6] 

• polyamide 66 (PA 66) [Nylon 66] 

• polybutylene terephthalate (PBT) 

• polyethylene terephthalate (PET) 

• polyetherimide 1010 moldable (PEI) 

• polyurethane 55D-90Adurameter hardness 

(PUR) 

• polyvinyl chloride flexible version (PVC) 
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These eight plastics will be referred to using their three 

letter abbreviation from here forward. One material, ABS 

Plastic, deteriorated in under one week in all three test 

fuels and could not be used any further. 

Several plastics including: ethylene vinyl alcohol 

(EVOH), polyamide 12 conductive version (PA 12) 

[Nylon 12], polyamide 46 (PA 46) [Nylon 46], 

polyphtalamide (PPA), high density polyethylene 

(HDPE), low density polyethylene (LDPE), 

polypropylene (PP), polyphenylene sulfide (PPS), 

polyoxymethylene (POM), Zytel® (HTN), and 

polyteraflouroethylene (PTFE) were not physically tested 

because they have been commonly used in the fuel 

system of flex-fuel vehicles and therefore have already 

been qualified for ethanol use. 

TEST FUEL 

The test fuel selection for this research was a major 

focus in the test plan development. In the review of the 

literature, several studies were identified where it was 

difficult to determine the specific composition of the base 

gasoline or ethanol components. The test fuels used in 

this study were based on the test-fuel standard specified 

in SAE J1681, Gasoline alcohol and diesel fuel 

surrogates for materials testing. This paper was the 

result of a task force formed in the early 1990’s for 

testing materials with methanol. Since then, the 

standard has been altered to include many fuels. The 

task force adopted ASTM Fuel C to use as a reference 

for gasoline in material compatibility testing. ASTM Fuel 

C represents a worst-case-scenario gasoline due to its 

composition of 50% iso-octane and 50% toluene. The 

iso-octane represents the alkane group that makes up 

40 to 70% of gasoline (Harrigan, Banda, Bonazza, 

Graham, Slimp, 2000, p. 2). It is important that the 

alkane group is represented for two reasons. First, they 

make up a large percentage of gasoline and second, 

they can cause swelling in polymers (plastics and 

elastomers). The toluene represents the aromatic group 

that makes up 20 to 50% of gasoline (p.2). Aromatics 

can cause swelling in polymers, but they also help 

suspend alcohols within the fuel mixture. 

Synthetic ethanol, not fuel-grade ethanol, should be 

used for materials testing because its known 

composition “will help to minimize some of the variables 

in the use of ethanol as a fuel test component” (Harrigan 

et al., p. 5). Many impurities can be found in fuel-grade 

ethanol including sulfuric acid, acetic acid, water, and 

sodium chloride. “The acid is formed either in the 

alcohol production process or due to oxidation of the 

alcohol during handling, transfer or storage” (p. 3). 

Water also is a by-product of production and can cause 

metal corrosion, especially when combined with sodium 

chloride. It is important that these are represented in the 

test fuel because they can cause material compatibility 

issues. As per SAE J1681, these impurities were added 

to the synthetic ethanol to form aggressive ethanol. 

Aggressive ethanol is a worst-case-scenario fuel that 

would still be acceptable under ASTM D4806, Standard 

specification for denatured fuel ethanol for blending with 

gasoline for use as automotive spark-ignition engine fuel

(ASTM, 2006). 

All fuels used in this study met SAE Standard J1681’s 

criteria. The three test fuels used included 

Surrogate gasoline [C] - ASTM Fuel C, 50/50 

toluene iso-octane mixture (500 ml toluene and 

500 ml iso-octane) 

E10 fuel [C(E10)A] - 90% Fuel C + 10% 

aggressive ethanol (450 ml toluene, 450 ml isooctane, 100 ml aggressive ethanol) 

E20 fuel [C(E20)A] - 80% Fuel C + 20% 

aggressive ethanol (400 ml toluene, 400 ml isooctane, 200 ml aggressive ethanol) 

Aggressive ethanol consists of: synthetic ethanol 816.00 

g, de-ionized water 8.103 g, sodium chloride 0.004 g, 

sulfuric acid 0.021 g, and glacial acetic acid 0.061 g 

(SAE J1681 Appendix E.1.2). 

APPARATUS 

The test samples were placed in 2-L glass jars with 

Teflon® lids. Stainless safety wire was used to suspend 

the samples in the test fluid and glass beads were used 

to keep the samples separated during the soaking 

period. The appropriate test solution was added to each 

of the jars and the test specimens were hung from the 

inner liner of the cap by stainless wire. The soaking 

apparatus is shown in Figure 1 below. The jars were 

placed in the oven at the elevated temperature for 18 

weeks. 

Figure 1. Test container 
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An explosion-proof friction air oven was used to maintain 

the samples at 55 ± 2 °C. It uses the heat generated by 

circulating air to maintain the temperature instead of an 

element or a flame. This is very important when heating 

combustible liquids in the presence of oxygen due to the 

potential for an explosion if the vapors were to come into 

contact with an ignition source. 

MEASURING EQUIPMENT 

Five primary pieces of measuring equipment were used 

to collect the physical property data for this study. A 

micrometer (0.001 in. precision) was used to measure 

the dimensions of each test sample. In addition, a 

micrometer with an anvil machined with the profile of the 

Izod notch was used to measure each notch depth. 

A Radwag WAX 220 analytical balance was used to 

measure the mass of the test samples. The balance has 

a linearity of ∀0.0002 g and a repeatability of 0.00015 g 

as outlined in the user’s manual. Based on the resolution 

and linearity of the scale, a weight change in a specimen 

less than 0.0008 g could be due to scale error and was 

not considered a measurable change. 

Figure 2. Satec pendulum impact tester 

A 16 ft-lb Satec, Model BLI universal pendulum impact 

tester (Figure 2) with a precision of 0.1 ft-lb was used to 

determine the impact resistance of each material. This 

machine was leveled and calibrated before testing and a 

correction table for windage and friction was developed. 

Figure 3. MTS 810 tensile testing system 

Finally, a MTS 810 material testing system with a 2,000-

lbf load cell was used to obtain tensile strength 

properties. A photo of the machine with one of the 

samples is shown in Figure 3. 

DATA COLLECTION 

Individual sample mass and dimensions were recorded 

before exposure to the test fluids. In addition to physical 

measurements, photos were taken of each sample to 

provide a reference of the original color and surface 

texture to be used at the conclusion of the study for 

comparison. The color of the solution was noted before 

each weekly fuel change. 

DATA ANALYSIS 

The data collected at the end of the study was compared 

to baseline values. All samples were measured before 

immersion and compared to the values recorded after 

the soak process along with the samples that were 

never exposed to any fuel. 

Appearance specimens were measured for volume 

change and mass gain or loss. Samples were compared 

from start to finish. 

Tensile testing results were compared to the results of 

test pieces that were never exposed to fuel. Tensile 

strength was calculated by the maximum load in 
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pounds-force by the average original (pre immersion) 

cross-sectional area in square inches. In addition, the 

percent elongation was determined by measuring the 

change in gage length from the original specimen to the 

fuel affected specimen. 

The immersed Izod impact test pieces were evaluated 

against the results of specimens which were not 

immersed. Impact resistance test results were measured 

in ft-lbf/in. Average impact resistances, along with the 

standard deviation to determine test variance and 

significance levels, were calculated from the physical 

data. Finally, the failure of each sample was visually 

analyzed to note the type of failure along with any air 

bubbles trapped in the specimen at the failure point. 

RESULTS 

An example photo of the various materials included in 

the study is displayed in Figure 4. The results of the 

study focused on comparison of the physical property 

changes of the materials after being immersed in each 

test fluid. Many of the materials demonstrated more 

discoloration when exposed to higher concentrations of 

ethanol-based fuels. However, it should be noted that 

discoloration does not necessarily indicate potential fuel 

system reliability problems. This study attempted to 

quantify the differences based on the tested physical 

properties. 

In many instances, samples immersed in both E10 and 

E20 demonstrated significant changes when compared 

to Fuel C. In those cases, the focus was placed on the 

differences between samples exposed to E10 and E20. 

Figure 4. Samples included in study 

VISUAL APPEARANCE CHANGE 

Many of the materials demonstrated more discoloration 

when exposed to the ethanol-blended fuels than they did 

when they were exposed to Fuel C. This discoloration 

appeared as a yellowing in some plastics and a 

darkening of the original color in other plastics. It was 

noticed that when the ethanol concentration increased 

from 10% to 20%, the level of discoloration also 

increased. 

Two materials, PUR and PVC, changed in size enough 

to be noticed visually. Photos of the two samples can be 

found in Figure 5 and Figure 6. The PVC samples 

shrunk approximately 35% in all three test fuels. The 

PUR samples increased in size in all three fuels but 

grew noticeably more in E10 and E20 than Fuel C. 

Finally, the PUR samples soaked in E10 and E20 

cracked immediately when removed from the fuel. The 

PUR samples immersed in E10 cracked but remained 

pliable, while the samples immersed in E20 cracked, 

hardened, and crumbled apart. 

Figure 5. PUR samples (from top row to bottom row: 

non-immersed, Fuel C, E10, and E20) 

Figure 6. PVC samples (from top row to bottom row: 

non-immersed, Fuel C, E10, and E20) 
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MASS LOSS/GAIN ANALYSIS 

The mass of each material sample was measured prior 

to and after the 3024-hour immersion period. Refer to 

Appendix B for a graph comparing the pre-immersion 

and post-immersion mass and Appendix C for the data. 

The post-immersion mass of PA 6, PA 66, PBT, PET, 

and PEI increased approximately 10% when exposed to 

both E10 and E20. No significant difference in mass 

change was noted between the above mentioned E10 

and E20 samples. 

PUR was the only sample that exhibited a mass change 

greater than 10% in the ethanol fuels while remaining 

constant in Fuel C. The greatest mass change of PUR 

occurred in E10. Finally, the PVC exhibited a mass loss 

of approximately 31% in all three fuels after being 

immersed. This indicates that the fuels extracted 

materials from PVC samples. 

VOLUME CHANGE ANALYSIS 

The measured volume change had a positive correlation 

to the mass change results. Refer to Appendix D for a 

graph comparing the pre-immersion and post-immersion 

volumes and Appendix E for the data. Samples of PA 6, 

PA 66, PBT, PET, and PEI immersed in E10 and E20 

yielded approximately a 10% increase in volume change 

when compared to Fuel C. The difference in volume 

change between samples immersed in E10 and E20 

varied less than 2%. 

The volume of PUR increased significantly between the 

pre-immersion and post-immersion measurements. The 

volume change in the samples immersed in E10 

increased 54.7%, while the samples immersed in E20 

increased 60.3%. Finally, the PVC samples’ volume 

decreased approximately 35% when immersed in any of 

the three fuels. 

TENSILE STRENGTH ANALYSIS 

The tensile strength characteristics of all samples were 

affected by immersion in the test fuels. Refer to 

Appendix F for a graph comparing the non-immersion 

and post-immersion tensile strengths and Appendix H 

for the data. Fuel C had a smaller effect than either the 

E10 or E20 test fuels. The tensile strength of the PA 6, 

PA 66, PBT, PET, and PEI materials all decreased after 

immersion. However, there was no significant difference 

between the change in tensile strength of samples 

immersed in E10 and E20. The PUR samples immersed 

in E10 lost 73% of their tensile strength, but the samples 

immersed in E20 cracked and broke before they could 

even be tested. 

TENSILE ELONGATION ANALYSIS 

While measuring the tensile characteristics of the 

samples, the percent of elongation data was collected. 

Refer to Appendix G for a graph comparing the nonimmersion and immersion elongations and Appendix H 

for the data. No significant differences were measured in 

the PET and PUR samples. As the ethanol 

concentration increased, the percent of elongation 

increased on the PA 6, PA 66, and PBT samples and 

decreased in the PUR samples. However, there was not 

a significant difference between the samples immersed 

in E10 and E20. The PVC samples demonstrated a 

significantly smaller percent of elongation when 

immersed in E20 compared to both Fuel C and E10. 

IMPACT RESISTANCE ANALYSIS 

Izod impact test results show no significant difference 

between the E10 and E20 test fuels. Refer to Appendix I 

for a graph comparing the non-immersion and 

immersion impact results and Appendix J for the data. 

Impact resistance increased on the PA 6, PA 66, PBT, 

and the PEI when compared to Fuel C. The PET impact 

resistance decreased for the E10 and E20 blends when 

compared to Fuel C. The impact resistance for the PBT 

samples soaked in Fuel C increased 72% while the 

impact resistance of the specimens soaked in E10 and 

E20 increased 300% and 384%, respectively. 

There were no differences in the type of fracture that 

occurred during the testing and there were no air 

bubbles present in the area of the break on any of the 

samples. The PVC samples immersed in all test fluids 

shrank to the point they could not be held in the Izod 

impact tester mounting fixture and, therefore, were not 

measured. Conversely, the PUR samples grew too large 

and could not be held in the test apparatus. 

CONCLUSIONS 

Using industry-recognized standards, this study tested 

eight different plastics found in automotive and small 

engine fuel systems to determine if they performed 

significantly different when immersed in Fuel C, E10, or 

E20. The study found that four of the materials, PA 6, PA 

66, PET, and PEI, were compatible with the three fuels. 

The other four materials, ABS, PUR, PVC, and PBT, 

were affected by all three fuels to varying degrees. 

The ABS specimens failed after less than one week of 

immersion in all three fuels. The specimens turned to a 

jelly-like mass in the bottom of the jars. This material 

was not compatible with any of the fuels. Finally, no 

automotive or small engine fuel system applications of 

ABS could be located, quite possibly due to its 

incompatibility with fuel. 
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PVC (flexible version) demonstrated significant changes 

in mass and volume in all three fuels but to a higher 

degree in ethanol fuels. The PBT data also showed 

significant changes in impact resistance in all three fuels 

but to a greater extent in the ethanol blends. PUR (55D90A durometer hardness) was deemed incompatible 

with both E10 and E20 due to cracking and changes in 

mass, volume, tensile strength, and elongation. In each 

case with PVC, PUR, and PBT both E10 and E20 

caused large enough changes to raise a concern. 

Because of this, these materials would be a poor choice 

for use with either E10 or E20. Finally, no fuel system 

components made of either PUR or PVC could be 

located. 

Different degrees of discoloration were observed in 

many of the other test samples, slight yellowing of 

plastics occurred on a few samples with E20 causing 

more yellowing. Samples were marked with an engraver 

for identification purposes. All can still be easily read 

with the exception of the PUR sample immersed in E20. 

Discoloration does not mean a failure in an automotive 

fuel system component. 

ACKNOWLEDGEMENTS 

This study would not have been possible without the 

support and recommendations from a number of 

individuals, organizations, and companies including 

Briggs & Stratton 

Delphi 

Ford Motor Company 

General Motors 

Intertek Automotive 

Jewitt and Associates 

Kohler 

Minnesota Corn Research and Promotion Council 

Minnesota Department of Agriculture 

Renewable Fuels Association 

S&S Cycle 

TI Automotive 

Toro 

Toyota 

Zen Fuel LLC / Michael Harrigan 

REFERENCES 

ASTM Recommended Practice, (2006). Standard 

specification for denatured fuel ethanol for blending with 

gasoline for use as automotive spark-ignition engine 

fuel. ASTM D4806. 

ASTM Recommended Practice, (2006). Standard test 

methods for determining the Izod pendulum impact 

resistance of plastic. ASTM D256. 

ASTM Recommended Practice, (2004). Standard 

specification for automotive spark-ignition engine fuel. 

ASTM D4814. 

ASTM Recommended Practice, (2003). Standard test 

method for tensile properties of plastics. ASTM D638. 

ASTM Recommended Practice, (2000). Standard 

practice for conditioning plastics for testing. ASTM D618. 

ASTM Recommended Practice, (1995). Standard 

practice for evaluating the resistance of plastics to 

chemical reagents. ASTM D543. 

Clean Air Act, 42 U.S.C. § 7547 (1977). 

Eisenthal, J. (2005, May). E20 Bill finally reaches Gov. 

Pawlenty’s desk. Minnesota Ag Connection. Retrieved 

October 22, 2005, from 

http://www.minnesotaagconnection.com/storystate.cfm?Id=405&yr=2005

Environmental Protection Agency. (1995, August 22). 

Waiver Requests under section 211 (f) of the clean air 

act. Retrieved October 28, 2005, from 

http://www.epa.gov/docs/OMSWWW/regs/fuels/additive/

waiver.pdf

Environmental Protection Agency. (1991, January 24). 

Regulation of fuels and fuel additives; Definition of 

substantially similar. Retrieved October 28, 2005, from 

http://www.epa.gov/otaq/regs/fuels/additive/jan91.pdf

Orbital Engine Company. (2003, May). Market barriers 

to the uptake of biofuels study: A testing based 

assessment to determine impacts of a 10% and 20% 

ethanol gasoline fuel blend on non-automotive engines - 

2000hrs material compatibility testing. Report to 

Environment Australia. 

Orbital Engine Company. (2003, May). Market barriers 

to the uptake of biofuels study: A testing based 

assessment to determine impacts of a 20% ethanol 

gasoline fuel blend on the Australian passenger vehicle 

fleet - 2000hrs material compatibility testing. Report to 

Environment Australia. 

Orbital Engine Company. (2003, March). Market barriers 

to the uptake of biofuels study: A testing based 

assessment to determine impacts of a 20% ethanol 

gasoline fuel blend on the Australian passenger vehicle 

fleet. Report to Environment Australia. 

SAE Recommended Practice, (2000, January). 

Gasoline, alcohol and diesel fuel surrogates for 

materials testing. SAE J1681. 
2/21/2008 

9

SAE Recommended Practice, (1998, January). Methods 

for determining physical properties of polymeric 

materials exposed to gasoline/oxygenate fuel mixtures. 

SAE J1748. 

Society of Automotive Engineers. (2000). A rational 

approach to qualifying materials for use in fuel systems. 

Warrendale, PA: Harrigan, M., Banda, A., Bonazza, B., 

Graham, P., & Slimp, B. 

Sun Refining and Marketing Company. (1988, April). 

Waiver application for 15% MTBE (EPA Publication No. 

EN-88-02, III-A-1). Washington, DC: U.S. Environmental 

Protection Agency. 

United States Department of Energy: Energy Efficiency 

and Renewable Energy. (2005, September 9). 

Minnesota passes E20 law. Retrieved October 22, 2005, 

from 

http://www.eere.energy.gov/afdc/progs/ddown.cgi?/WHA

TS_NEW/480/1/0

TERMINOLOGY 

E10 - Fuel consisting of 90% gasoline and 10% ethanol 

E20 - Fuel consisting of 80% gasoline and 20% ethanol 

ASTM Test Fuel C - Test Fuel C is composed of 50% 

toluene and 50% iso-octane 

Aggressive ethanol - Synthetic ethanol 816.00 g, deionized water 8.103 g, sodium chloride 0.004 g, sulfuric 

acid 0.021 g, and glacial acetic acid 0.061 g (SAE J1681 

appendix E.1.2)

C(E10)A - Fuel consisting of 90% ASTM test Fuel C and 

10% aggressive ethanol 

C(E20)A - Fuel consisting of 80% ASTM test Fuel C and 

20% aggressive ethanol 

CONTACT 

Department of Automotive Engineering Technology 

Minnesota State University, Mankato 

205 Trafton Science Center East, Mankato MN 56001 

507-389-6383 
2/21/2008 

10

APPENDIX A 

 MnCAR 

Minnesota Center for Automotive Research 

 

FROM Bruce Jones, Gary Mead, & Paul Steevens 

 Minnesota Center for Automotive Research 

 Minnesota State University, Mankato 

 Trafton Science Center 205E 

 Mankato, MN 56001 

 (507) 389-6383 

 (507) 389-5002 (fax) 

RE E20 Material Compatibility Testing Procedures - Plastics 

Introduction 

This document is intended to outline the testing procedures used by the Minnesota Center for Automotive Research 

(MnCAR) for the purpose of measuring the material compatibility characteristics of plastics commonly found in automotive 

fuel systems. The purpose of this testing is to determine if Fuel C(E20)A will have a larger negative impact on fuel system 

plastics than Fuel C or Fuel C(E10)A. The following properties and changes were measured before and after immersion: 

volume/swell, weight, appearance, tensile strength, elongation, and impact resistance. 

Standards Used 

Proposed testing will follow the procedures outlined in 

 SAE J1748-98 Methods for determining physical properties of polymeric materials exposed to 

gasoline/oxygenate fuel mixtures 

 SAE J1681-00 Gasoline, alcohol, and diesel fuel surrogates for material testing 

ASTM D618-00 Standard practice for conditioning plastics for testing

ASTM D543-95 Standard practice for evaluating the resistance of plastics to chemical reagents 

ASTM D638-03 Standard test method for tensile properties of plastics

ASTM D256-06 Standard test methods for determining the Izod pendulum impact resistance of plastics

Properties Examined

 volume/swell 

 weight 

 appearance 

 tensile strength 

 elongation 

 impact resistance 
2/21/2008 

11

Plastics to Test 

ABS Acrylonitrile Butadiene Styrene 

PA 6 Polyamide - Nylon 6 

PA 66 Polyamide - Nylon 66 

PBT Polybutylene Terephthalate 

PET Polyethylene Terephthalate (Mylar) 

PUR Polyurethane 

PVC Polyvinyl Chloride 

PEI Polyetherimide (GE Ultem) 

Test Fuels 

Three test fuels will be used consisting of 

C Surrogate gasoline- "base” ASTM Fuel C 50/50 toluene iso-octane mixture (500 ml toluene and 500 

ml iso-octane) 

C(E10)A E10 fuel- 90% Fuel C + 10% aggressive ethanol (450 ml toluene, 450 ml iso-octane, 100 ml 

aggressive ethanol) 

C(E20)A E20 fuel- 80% Fuel C + 20% aggressive ethanol (400 ml toluene, 400 ml iso-octane, 200 ml 

aggressive ethanol) 

 

Aggressive ethanol consists of: synthetic ethanol 816.00 g, de-ionized water 8.103 g, sodium chloride 0.004 g, sulfuric 

acid 0.021 g, and glacial acetic acid 0.061 g (SAE J1681 Appendix E.1.2) 

Specimen Preparation and Condition 

1. Prepare five appearance change disks and tensile specimens for each material being tested and for each test fuel 

being used. 

Note: An extra set of five tensile specimens of each material will be needed to determine non-immersion 

properties. Prepare ten Izod specimens for each material being tested and for each test fuel being used. An extra 

set of ten Izod specimens of each material will be needed to determine non-immersion properties (SAE J1748 

5.1.2, ASTM D543 12.2). 

2. Specimen Sizes (SAE J1748 6.1.1, 6.1.2) 

 Specimens for Weight, Dimension, and Appearance Change: Disks 50.8 mm (2 in.) x 3.175 mm (0.125 in.) 

Specimens for tensile strength: Type 1 dumbbell tensile specimens 165 mm (6.5 in.) x 19 mm (0.75 in.) x 1.6 mm 

± 0.25 mm (0.065 in. ± 0.010 in.) that neck down to 13 mm + 0.00 mm – 0.10 mm (0.500 in. + 0.000 in. -0.004 

in.) 

Specimens for Izod impact test: 12.7 mm (0.5 in.) X 12.7 mm (0.5 in.) x 63.5mm (2.5 in.) X 2.54 mm (0.100 in.) 

Izod notch on center. 

3. All test and surrogate specimens will be conditioned in accordance with ASTM D618 Procedure A. 

ASTM D 618 Procedure A 

Condition specimens under 7 mm (0.25 in.) thick for a minimum of 40 hours at 23 °C ± 2 °C at 50% ± 5% 

humidity. For specimens over 7 mm (0.25 in.) thick, condition for 88 hours at 23 °C ± 2 °C at 50% ± 5% humidity. 

Allow adequate air circulation to all specimens by either hanging from metal clips, or placing them on a wire 

screen with at least 25 mm (1 in.) of room between them and the bench (ASTM D618 8.1). 

Immersion 

1. Prepare and condition specimens in the manner described above. 

2. Photograph all specimens to show color and surface texture. 

 

3. After conditioning, weigh each specimen on an analytical balance in grams to four decimal places (SAE 1748 4.1.3). 
2/21/2008 

12

4. Measure the dimensions of each specimen, subtracting any holes, using a micrometer accurate to 0.0001 in. to 

calculate surface area (ASTM D543 5.1, 5.2). 

Weight/dimension change specimens: Measure two diameters at right angles to each other and the thickness in 

the center (ASTM D543 11.1). 

Tensile specimens: Measure the width and thickness of the specimens at the center and within 5 mm of each 

end of the gage length (ASTM D638 10.1.1). 

Izod specimens: Measure the width, thickness, and notch depth (ASTM D256-06 7.2). 

5. Fill the glass containers with the appropriate test fluid to at least 1 cm above the specimen, while maintaining a test 

fuel volume to specimen surface area ratio of 10 mL/in2

 for nonextractable plastics and 40 mL/in2 for specimens which 

have extractable plasticizers. Use the larger ratio if unsure (SAE J1748 4.1.2, ASTM D543 11.2). 

6. Place the container in the oven and allow the test fuel to reach 55 °C ± 2 °C (SAE J1748 5.1.2). 

7. Once the test fuel temperature has stabilized, place the test specimens of the same material in each of the test fuels. 

Seal the containers to avoid evaporative losses. Suspend the specimens to avoid contact with the walls or bottom of the 

container using stainless steel wire and glass beads to separate each specimen. It may be necessary to attach small 

weights, such as nichrome, to prevent floating (ASTM D543 11.2). 

8. Replace the fuel weekly (SAE J1748 5.1.2). 

9. Continue exposure for 3000 hours (SAE J1748 5.1.3). 

Change in Weight, Dimension, and Appearance (ASTM D543) 

1. After equilibrium or a predetermined time is reached, remove the containers from the oven and allow them to cool 24 

hours before measurements are taken (SAE J1748 5.1.2). 

2. Remove the specimens from the test fuel and place in the measurement fixture. Measure two diameters at right 

angles to each other and the thickness in the center. All dimensional measurements are taken while the specimen is wet 

and within 30 seconds of removing it from the fuel (SAE J1748 6.1.1, ASTM D543 11.1). 

3. Blot dry the specimen being careful not to disturb the surface and place in a tarred weighing bottle within 10 seconds 

to minimize evaporative weight loss. Weigh each specimen to the same level of precision as the initial weighing (SAE 

J1748 6.1.1, ASTM D543 11.4). 

4. Examine the appearance of each specimen noting any loss of gloss, developed texture, decomposition, discoloration, 

swelling, clouding, tackiness, rubberiness, crazing, bubbling, cracking, solubility, etc... (ASTM D543 11.5). 

5. Photograph all specimens to show color and surface texture. 

Tensile Strength (ASTM D638) 

1. After equilibrium or a predetermined time is reached, remove the containers from the oven and allow them to cool for 

24 hours before measurements are taken (SAE J1748 5.1.2). 

2. Testing is to take place within 5 minutes of removing the specimen from the fuel to minimize the effects of dryout (SAE 

J1748 6.1.2). 

3. Tensile testing shall be performed on a machine meeting all requirements of Section 5 of ASTM D638. 

4. Test at least five specimens for each material in the case of isotropic materials and ten specimens in the case of 

anisotropic materials (ASTM D638 7.1). 

5. Test all specimens at a rate of 5 mm/min ± 25% (ASTM D638 8.2). 
2/21/2008 

13

6. Determine mechanical properties of non-immersed specimens prepared from the same material lot, conditioned in the 

same manner, and tested under the same conditions (ASTM D543 12.2). 

7. Base all calculations on the original measurements taken before immersion (SAE J1748 6.1.2). 

Izod Impact (ASTM D256-06)

1. After equilibrium or a predetermined time is reached, remove the containers from the oven and allow them to cool for 

24 hours before measurements are taken (SAE J1748 5.1.2). 

2. Testing is to take place within 5 minutes of removing the specimen from the fuel to minimize the effects of dry-out 

(SAE J1748 6.1.2). 

3. Impact testing shall be performed on a machine meeting all requirements of section 6 of ASTM D256. 

4. Test at least five and preferably ten or more individual determinations of impact resistance (ASTM D256 10.1). 

5. Measure windage and friction of the machine to calculate out of the sample test (ASTM D256 10.3). 

6. Measure and record the width of each specimen after notching to the nearest 0.025 mm (.0001 in.) (ASTM D256 

10.5). 

7. Position the specimen rigidly and securely in the vice. Release the pendulum and record the indicated breaking energy 

(ASTM D256 10.7). 

8. Record the type of break from failure category: complete, hinge, partial, or non-break (ASTM D256 5.8). 

9. Calculate the average Izod impact resistance of the group of specimens (ASTM D256 10.10). 
14

APPENDIX B 

Plastic Apperance Disk Mass

0.02.04.06.08.0

10.012.014.0

PA6-CPA6-E10 PA6-E20 PA66-C PA66-E10 PA66-E20 PBT-CPBT-E10 PBT-E20 PET-CPET-E10 PET-E20 PEI-CPEI-E10 PEI-E20 PUR-CPUR-E10 PUR-E20 PVC-C

Mass in Grams 
15

APPENDIX C 

Minnesota State University, Mankato

E20 Plastics Study Apperance Disk Mass Results

Average of All Tests

Fuel C E10 E20 Fuel C E10 

ABS Pre-Immersion 6.663 6.584 6.578 PET Pre-Immersion 9.594 9.60

Post Immersion Failed in all three test Fuels Post Immersion 9.764 9.96% Change % Change 1.8 3

Pre-Immersion Std Dev 0.03 0.13 0.10 Pre-Immersion Std Dev 0.03 0.0Post Immersion Std Dev Post Immersion Std Dev 0.04 0.0

Fuel C E10 E20 Fuel C E10 

PA6 Pre-Immersion 7.255 7.236 7.236 PEI Pre-Immersion 8.011 7.97

Post Immersion 7.210 7.868 7.916 Post Immersion 8.045 8.15% Change -0.6 8.7 9.4 % Change 0.4 2

Pre-Immersion Std Dev 0.03 0.03 0.03 Pre-Immersion Std Dev 0.02 0.0Post Immersion Std Dev 0.03 0.03 0.02 Post Immersion Std Dev 0.03 0.0

Fuel C E10 E20 Fuel C E10 

PA66 Pre-Immersion 7.095 7.129 7.126 PUR Pre-Immersion 7.746 7.75

Post Immersion 7.074 7.691 7.767 Post Immersion 9.147 11.82% Change -0.3 7.9 9.0 % Change 18.1 52

Pre-Immersion Std Dev 0.03 0.02 0.02 Pre-Immersion Std Dev 0.03 0.0Post Immersion Std Dev 0.03 0.03 0.02 Post Immersion Std Dev 0.03 0.4

Fuel C E10 E20 Fuel C E10 

PBT Pre-Immersion 8.154 8.143 8.140 PVC Pre-Immersion 7.574 7.59

Post Immersion 8.426 8.642 8.637 Post Immersion 5.164 5.26% Change 3.3 6.1 6.1 % Change -31.8 -30

Pre-Immersion Std Dev 0.04 0.03 0.04 Pre-Immersion Std Dev 0.03 0.0Post Immersion Std Dev 0.04 0.03 0.04 Post Immersion Std Dev 0.03 0.0

Weight in Grams Weight in GramsWeight in Grams Weight in GramsWeight in Grams Weight in GramsWeight in Grams Weight in Grams
16

APPENDIX D 

Plastic Apperance Disk Volume 

0.000.100.200.300.400.500.600.70

PA6-CPA6-E10 PA6-E20 PA66-C PA66-E10 PA66-E20 PBT-CPBT-E10 PBT-E20 PET-CPET-E10 PET-E20 PEI-CPEI-E10 PEI-E20 PUR-CPUR-E10 PUR-E20 PVC-CPVC-E10 PVC-E20

Volume in Cubic

 Inches
17

APPENDIX E 

Minnesota State University, Mankato

E20 Plastics Study Apperance Disk Volume Results

Average of All Tests

Fuel C E10 E20 Fuel C E10 

ABS Pre-Immersion 0.399 0.399 0.399 PET Pre-Immersion 0.384 0.

Post Immersion Failed in all three test Fuels Post Immersion 0.395 0.% Change % Change 2.8 

Pre-Immersion Std Dev 0.00 0.00 0.00 Pre-Immersion Std Dev 0.00 0

Post Immersion Std Dev Post Immersion Std Dev 0.00 0

Fuel C E10 E20 Fuel C E10 

PA6 Pre-Immersion 0.404 0.399 0.400 PEI Pre-Immersion 0.392 0.

Post Immersion 0.402 0.442 0.447 Post Immersion 0.394 0.% Change -0.5 10.7 11.7 % Change 0.5 

Pre-Immersion Std Dev 0.00 0.00 0.00 Pre-Immersion Std Dev 0.00 0

Post Immersion Std Dev 0.00 0.00 0.00 Post Immersion Std Dev 0.00 0

Fuel C E10 E20 Fuel C E10 

PA66 Pre-Immersion 0.391 0.392 0.392 PUR Pre-Immersion 0.408 0.

Post Immersion 0.389 0.428 0.432 Post Immersion 0.502 0.% Change -0.3 9.2 10.4 % Change 22.8 5

Pre-Immersion Std Dev 0.00 0.00 0.00 Pre-Immersion Std Dev 0.00 0

Post Immersion Std Dev 0.00 0.00 0.00 Post Immersion Std Dev 0.00 0

Fuel C E10 E20 Fuel C E10 

PBT Pre-Immersion 0.390 0.390 0.389 PVC Pre-Immersion 0.399 0.

Post Immersion 0.405 0.424 0.420 Post Immersion 0.256 0.% Change 3.8 8.8 7.8 % Change -35.9 -3

Pre-Immersion Std Dev 0.00 0.00 0.00 Pre-Immersion Std Dev 0.01 0

Post Immersion Std Dev 0.00 0.01 0.00 Post Immersion Std Dev 0.00 0

Volume in Cubic Inches Volume in Cubic InchesVolume in Cubic Inches Volume in Cubic InchesVolume in Cubic Inches Volume in Cubic InchesVolume in Cubic Inches Volume in Cubic Inches
18

APPENDIX F 

Plastic Tensile Results

0

5000

10000150002000025000

PA6-Control PA6-CPA6-E10 PA6-E20 PA66-Start PA66-C PA66-E10 PA66-E20 PBT-Start PBT-CPBT-E10 PBT-E20 PET-Start PET-CPET-E10 PET-E20 PEI-Start PEI-CPEI-E10 PEI-E20 PUR-Start PUR-C PUR-E10 PUR-E20 PV

Tensile PSI 
19

APPENDIX G 

Plastic Tensile Elongation 

011223344

PA6-Control PA6-CPA6-E10 PA6-E20 PA66-Start PA66-C PA66-E10 PA66-E20 PBT-Start PBT-CPBT-E10 PBT-E20 PET-Start PET-CPET-E10 PET-E20 PEI-Start PEI-CPEI-E10 PEI-E20 PUR-Start PUR-C PUR-E10 PUR-E20 PV

Elongation (inches)
20

APPENDIX H 

Minnesota State University, Mankato

E20 Plastics Study Tensile Results

Average of All Tests

ABS

Tensile (PSI) Std Dev % Change

PET

Tensile (PSI) Std Dev % Change

Pre-Soak 6858 121 Pre-Soak 23191 247

Fuel C Samples failed in under one week C 22507 113 -2.9% E10 Samples failed in under one week E10 17239 126 -25.7% 

E20 Samples failed in under one week E20 17224 153 -25.7% 

PA6

Tensile (PSI) Std Dev % Change

PEI

Tensile (PSI) Std Dev % Change

Pre-Soak 7203 758 Pre-Soak 15957 73C 11103 1042 54.1% -60.6% C 16449 78 3.1% 

E10 5147 2 -28.5% 162.3% E10 15725 80 -1.5% 

E20 4912 72 -31.8% 192.1% E20 15681 62 -1.7% 

PA66

Tensile (PSI) Std Dev % Change

PUR

Tensile (PSI) Std Dev % Change

Pre-Soak 9200 181 Pre-Soak 1414 50C 12324 62 34.0% -54.7% C 914 75 -35.4% 

E10 6162 61 -33.0% 187.1% E10 386 73 -72.7% 

E20 6029 2 -34.5% 206.3% E20 All Samples Cracked

PBT

Tensile (PSI) Std Dev % Change

PVC

Tensile (PSI) Std Dev % Change

at start 8101 48 Pre-Soak 714 2C 5735 1 -29.2% 325.7% C 571 2 -20.0% E10 4544 60 -43.9% 413.1% E10 435 1 -39.1% E20 4618 76 -43.0% 455.9% E20 429 3 -40.0% 

% Change in 

Elongation

% Change in 

Elongation

% Change in 

Elongation

% Change in 

Elongation
21

APPENDIX I 

Plastics Izod Impact

02468

1012

PA6-Control PA6-CPA6-E10 PA6-E20 PA66-Start PA66-C PA66-E10 PA66-E20 PBT-Start PBT-CPBT-E10 PBT-E20 PET-Start PET-CPET-E10 PET-E20 PEI-Start PEI-CPEI-E10 PEI-E20 PUR-Start PUR-C PUR-E10 PUR-E20 PV

Average Ft-lbs/In
22

APPENDIX J 

Izod ResultsAverage All Izod impact Tests

Average Ft-Lbs/In Average Ft-Lbs/In

ABS Control C E10 E20 PET Control C E10 E20Average 1.76 Failed in all three test fuels Average 3.64 4.03 3.40 3.60

stand div 0.28 stand div 0.38 0.24 0.76 0.31Percent change from Percent change from 10.60 -6.73 -1.11test fuel to Control test fuel to ControlPA6 Control C E10 E20 PEI Control C E10 E20Average 4.58 3.36 3.98 3.79 Average 2.70 2.56 3.28 3.23stand div 0.23 0.14 0.21 0.77 stand div 0.29 0.04 0.14 0.21Percent change from -26.60 -13.18 -17.13 Percent change from -5.30 21.31 19.36test fuel to Control test fuel to Control

grew cracked

PA66 Control C E10 E20 PUR Control C E10 E20Average 2.22 3.37 4.26 4.29 Average 4.03 Could not be tested in any fuelstand div 0.55 0.42 0.32 0.52 stand div 0.15Percent change from 51.81 92.07 93.26 Percent change fromtest fuel to Control test fuel to Control

shrank

PBT Control C E10 E20 PVC Control C E10 E20Average 1.82 3.14 7.27 8.81 Average 0.92 Could not be tested in any fuel stand div 0.17 0.42 0.89 0.73 stand div 0.05Percent change from 72.73 299.51 384.18 Percent change fromtest fuel to Control test fuel to Control

Minnesota State University, Mankato

E20 Plastics Study