DuPont / Mohawk / PTT Poly Canada Revised Petition

m
E. I. du Pont de Nemours and 	Mohawk Industries, Inc. 	PTT Poly Canada
Company
September 7, 2006
Office of Secretary
Federal Trade Commission
600 W. Pennsylvania Ave., NW
Washington, DC 20580
Revised Petition To Establish A New Generic Subclass
Mohawk Industries, Inc.1 (Mohawk), E. I. du Pont de Nemours and Company2 (DuPont), and
PTT Poly Canada3 (PTT Canada) (collectively “Petitioners”) hereby submit this Revised
Petition to the Federal Trade Commission (the “Commission”) for the establishment of a new
generic subclass within the existing polyester category for fibers made from poly(trimethylene
terephthalate) (“PTT”) to restate and supplement the contents of the Petition dated February,
21, 2006 in order to address certain questions raised by the Commission. Petitioners note the
Commission’s April 18, 2006 action taken in response to the February 21, 2006 Petition
assigning 	the 	designation 	“PTT001” 	for 	PTT 	fiber 	for 	temporary 	use 	until 	a 	final
determination is made by the Commission as to the merits of this Petition. 	Petitioners
propose in order of preference the following names for a new generic subclass of polyester
that may be used with respect to PTT fibers: 1. triexta; 2. resisoft; and 3. durares.
1 Mohawk was founded more than 120 years ago and today is the leading producer and distributor of flooring
worldwide. Mohawk products serve all major flooring categories: carpet, rugs, hardwood, laminate, ceramic tile,
and vinyl flooring. Mohawk has launched a line of carpets manufactured from PTT and sells such carpets under
the trademark SmartStrand.
2 Founded in 1802, DuPont is a science company operating in more than 70 countries. DuPont offers a wide
range of innovative products and services for markets including agriculture, nutrition, electronics,
communications, safety and protection, home and construction, transportation and apparel. DuPont markets PTT
under the trademark Sorona®.
3 PTT Poly Canada is a 50 / 50 Limited Partnership between Shell Chemicals Canada LTD and SGF Chimie, a
subsidiary of Societe Generale de Financement du Quebec (SGF). PTT Poly Canada markets PTT under the
trademark Corterra® Polymers.

Summary of Petition
Petitioners seek to establish a generic subclass for fibers spun from PTT on the grounds that
such fibers satisfy the three tests required by the Commission for the use of a generic
subclass.4 These tests are satisfied by fibers spun from PTT because:
1. 	PTT fiber has the same general chemical composition as the Commission’s established
polyester generic fiber category.
2. 	PTT fiber, while having the general chemical composition of polyester, has distinctive
properties of importance to the general public as a result of its unique chemistry,
molecular design, and fiber structure. These properties are durability, resilience,
softness, and stretch with recovery.
PTT fiber’s distinctive features of durability, resilience, softness, and stretch with recovery
make PTT fiber suitable for uses which conventional polyester (PET) is significantly less well
suited. These features are as follows:
a) Carpet applications: Durability and softness.
b) Apparel applications: Softness and stretch with recovery.
Fiber Attributes Of Importance In Markets Where PTT Fiber Is Used
An important issue in an application for a generic subclass is the requirement that the
distinctive features of any new polymer or fiber be important to the general public, and that
such features make the fiber suitable for uses for which other fibers which fall under the
established generic name are not suited, or would be significantly less well suited.
Since the distinctive features of a fiber may differ from application to application, it is useful
to first discuss the two fiber markets where fibers made from PTT are used so that the
properties of PTT can be compared to the properties of the other polyester that is used for
fiber applications. 	These markets are apparel and residential carpet. 	In these markets, the
form 	of 	polyester 	that 	is 	most 	widely 	used 	is 	poly(ethylene 	terephthalate) 	(“PET”).
Accordingly, Petitioners will provide data comparing the chemistry and crystalline structure
4 These factors were identified as follows by the Commission in its Notice of Proposed Rulemaking of February
15, 2002 appearing at 67 FR 7104:
“Thus, a new generic fiber subclass may be appropriate in cases where the proposed subclass fiber: (1) Has the
same general chemical composition as an established generic fiber category; (2) has distinctive properties of
importance to the general public as a result of a new method of manufacture or substantially differentiated
physical characteristics, such as fiber structure; and (3) the distinctive feature(s) make the fiber suitable for uses
for which other fibers under the established generic name would not be suited, or would be significantly less well
suited.”
2

of PTT to PET and the performance of fibers made from these polymers in carpet and apparel
applications.5
Residential Carpet
Prior to the launch of residential carpet made from PTT by Mohawk Industries, Inc. and Shaw
Industries, Inc. (the two largest United States suppliers of carpet for the residential market),
the four principal types of man-made fiber used to manufacture carpet were nylon, PET
polyester, and polypropylene. Of these four materials, nylon carpet offered the broadest range
of attributes most highly valued by consumers. 	As a result, for comparable carpet
constructions, nylon carpet has commanded the highest price. 	Carpet made from PET has
been less highly regarded because PET fiber lacks the durability and resilience of nylon and
because, compared to many recent nylon carpet constructions, PET fibers were less flexible
and not as soft as some nylon constructions.
With the launch of carpet based on PTT, consumers have a choice of a fiber that has stain
resistance properties superior to nylon, together with durability, resilience and softness that
matches the highest quality constructions of nylon residential carpet.
In a 2004 study of consumer purchasing preferences6, 1600 consumers between 25 and 64
years of age who shopped for carpet in the past were asked questions pertaining to carpet fiber
performance and preferences. A list of those carpet attributes that relate to fiber performance
and the percentages of consumers who rated the attribute as very important is in Table 1
below. The attributes where PTT fiber has a significant performance advantage in residential
applications over PET fiber because of its physical and chemical properties are highlighted in
bold italics.
Table 1: Consumer preferences in carpets
Attribute 	Percentage Rating Attribute As Very Important
Common spills and pet accidents can be removed
easily even after they have dried
69%
The carpet will stand up to years of foot traffic
without matting down
67%
Dirt and soil can be removed easily from the carpet
with regular vacuuming
66%
Areas where spills have been cleaned will not be
visible
64%
5 In addition, Petitioners will provide data comparing the performance of PTT in carpet applications to the
performance of nylon carpet because nylon currently has the largest market share in residential carpet.
Accordingly, the properties of nylon fibers are a useful reference to define those features of PTT carpet fibers
that are of importance to the general public.
6 Data taken from a August 23, 2004 study titled Carpet Fiber Performance and Preferences prepared for
Mohawk Industries by the Brandware Group.
3

Stain resistant properties will not diminish over the
life of the carpet
63%
Soil resistance properties will not diminish over the
life of the carpet
61%
The pile of the carpet stays tight and will stand up
like new after normal vacuuming
58%
The color of the carpet will stay the same year after
year and never fade, even in direct sunlight
56%
Heavy soil and most stains can be removed from
the carpet with just plain water
53%
The carpet pile will not shed or fuzz 	53%
The carpet is soft and comfortable to sit on or lie
on
49%
The carpet can be professionally cleaned as often
as you want
36%
The carpet never shows tracks from footprints or
vacuuming
27%
The carpet will never produce static shock, even if
you walk on it in wool socks
24%
Apparel
There are many man-made fibers used in the apparel industry, and the supply chain is far
more complex than in the carpet industry. 	However, it is still possible to obtain market
requirements 	information 	thru 	a 	carefully 	designed 	“voice 	of 	customer” 	process 	by
interviewing fabric buyers and brand managers in the apparel industry. 	These steps in the
supply chain determine what fabrics are made into garments for the consumer public. Fabric
buyers and brand managers understand the downstream requirements and must match that
demand to the supply of fabrics and in turn what polymers and fibers are used in those fabrics.
In order to understand these preferences, DuPont conducted a survey7 of downstream
participants in the supply chain to determine preferences in the apparel supply chain where
differences in fabric fiber content were important and discernable. 	Table 2 lists the
companies that were surveyed in the countries which are the major sources of fabrics made
from man-made fibers. 	The purpose of the survey was to determine the attributes of fabrics
that are of greatest importance to consumers.
7 This study was conducted by DuPont employees in the first and second quarter of 2004.
4

5
Boxplots of Importan by Attribut
(means are indicated by solid circles)
Table 2: Apparel fabric preferences survey participants
Country 	Fabric Producer or Purchaser
Korea 	Li & Fung, C&A/Mondial, Sears, SAE-A
Trading Company, Mastex, Liz Claiborne,
Mast Industries
Taiwan 	Esquel, Levi, TAL, Adidas, Li & Fung,
Nike, Puma, Eddie Bauer
China 	Burringtex, Liz Claiborne, Federated, May
Co., Mast, Newtimes Jones (Jones New
York)
Survey participants were asked to rate the following attributes on a scale of 0 to 5. The results
are shown in Figure 1 with the mean denoted by the small square and the range denoted by
the box. The average of the responses is the horizontal line.
1. 	Stretch
2. 	Softness (also referred to as “Drape”)
3. 	Easy Dye
4. 	Easy Care
5. 	Made from renewable resources
6. 	Stain resistance
7. 	Resilience
8. 	Printability
From this list of eight attributes, the three which had the greatest importance were easy care,
softness (hand or drape), and stretch with recovery. 	PTT fiber is superior to PET fiber with
Figure 1: Fabric survey results – Box represents 95% of questionnaire responses;
red dot equals the numerical average of responses; horizontal line equals the mean of
the responses; and vertical line equals high and low ranges of responses.
0
1
2
3
4
5
Importance
Attribute
Care	
Dye
Green	
Prints
Resilience
Soft
Stain Res.
Stretch

respect to two of these three attributes: softness and stretch with recovery.
Discussion of Factors Needed For The Designation Of A New Generic
Subclass For Fibers Spun From PTT Polymer
Section 1. 	PTT polymer and fibers spun from PTT have the same general chemical
composition as the FTC’s established polyester generic fiber category.
Rule 7(c) defines "polyester" as "[a] manufactured fiber in which the fiber-forming substance
is any long chain synthetic polymer composed of at least 85% by weight of an ester of a
substituted aromatic carboxylic acid, including but not restricted to substituted terephthalate
units, [formula omitted] and para substituted hydroxy-benzoate units, [formula omitted]." 16
CFR 303.7(c).
PTT polymer is made by reacting (a) dimethyl terephthalate (DMT) or terephthalic acid
(TPA), both of which are substituted aromatic carboxylic compounds, and (b) 1,3-propanediol
(PDO) to form a long chain synthetic polymer consisting of more than 85% of substituted
terephthalate esters. 	Accordingly, fiber made from PTT polymer has the same chemical
composition as is described by Rule 7(c).
Section 2. PTT fiber, while having a chemical composition which causes it to fall within
the definition provided for polyester set forth in 16 CFR 303.7(c), has distinctive
properties of importance to the general public as a result of its unique chemistry,
molecular design, and fiber structure.
The generic class of aromatic polyesters today consists of several different chemical
formulations including poly(ethylene terephthalate) (PET) and PTT. 	The type of polyester
that is familiar to consumers because of its use in carpet and apparel applications is PET.
However, the molecular differences between PET and PTT are quite profound, and result in
significantly 	different 	physical 	properties 	of 	fibers. 	These 	properties 	are 	(a)
durability/resilience for carpet applications, (b) softness for both consumer carpet and apparel
applications, and (c) stretch and recovery for apparel applications.
a) 	Durability/Resilience
Fiber durability, which in carpet applications is measured by the resiliency of the fiber and its
ability to recover from compression, is together with stain resistance the most important
property that consumers look to when selecting a residential carpet as shown in the consumer
survey results set forth above. This property is inherently better in fibers made from PTT vs.
PET because of PTT’s chemistry and molecular design. PET and PTT crystallize into triclinic
unit cells during fiber formation. However, the glycol portion of their chemical chains
crystallizes into different conformations. The two methylene units in the glycol portion of
PET are arranged trans to each other, whereas the three methylene units in PTT are arranged
in a gauche-gauche conformation as shown in Figure 2 below:
6

Figure 2. PTT molecule showing gauche-gauche Conformation (ref. 1)
Because of the methylene diol’s conformations, PTT chains are contracted by 24.7% while
the PET chain is fully extended. 	Also the benzene ring of the terephthalic ester groups of
PET are oriented parallel to each other in every chemical repeating unit. However, the
orientation of PTT’s benzene ring in the successive terephthalic ester units is at an angle to
each other), thus PTT molecular chain forms a 2/1 helix, which is made up of two repeating
units per turn which introduces a zigzag shape to the polymer chain. 	This difference is
illustrated in Figure 3 which compares the molecular structures of PET and PTT. As a result
of this structure, compressive forces translate at the molecular level to bending and twisting of
bonds, rather than just stretching. 	The molecular structure of PTT is more like a coil spring
compared to a straight wire structure in the case of PET polyester.8 Therefore, PTT fiber can
take an additional level of applied strain and recover completely.
8 This property of PTT polymer has also been confirmed through study of x-ray diffraction patterns which occur
when fibers of PTT are subjected to stress. See Crystal Deformation in Aromatic Polyester, Journal of Polymer
Science, Vol. 13, 799-813 (1975) ref 2.
7

Figure 3: Structural differences between PET and PTT (ref 3)
Error!
(a) 	(b)
Arrangement of PET (a) and PTT (b) crystalline molecular chains. 	Arrow indicates
the alignment direction of the benzene ring.
Accordingly, when a PET fiber is subjected to compression forces in carpet applications (e.g.,
when carpet is walked on or subjected to carpet industry tests that simulate foot traffic), the
molecular chain structure of PET changes and develops a larger permanent set or crystal
deformation which is not completely recoverable. 	This causes consumer carpet made from
PET polyester to develop a crushed appearance where the carpet fibers do not continue to
stand up as they did when the PET carpet was new.
In the case of PTT, compression forces in carpet applications cause the molecular chain
structure to deform. However, the crystalline structure is able to recover without developing a
permanent set. 	The carpet fibers continue to stand up and appear new for a significantly
longer period of time. The basis for this performance difference is the molecular structure of
the two polymers, extended to larger physical properties differences such as crimp retention
as shown in Figure 4 below:
8

Figure 4: Crimp recovery of PET and PTT BCF yarns (Shell internal study)
% Crimp Recovery
100
80
60
40
20
0
0.00 	0.50 	1.00 	1.50
Tension, g/den.
PET
PTT
b) 	Softness
Softness is important to the consumer for both carpet and apparel applications. 	Consumers
judge the softness of a residential carpet by touching or walking on the upright twisted fibers
or yarns. 	The ease with which the yarns bend over is a measure of softness. 	Consumers
judge the softness of a fabric by assessing its hand or drape (the ease with which conforms to
the shape of the body). The degree of softness in both cases is proportional to the amount of
force required to bend the fiber. The laboratory measurement of the amount of force required
to bend a fiber is know as fiber modulus, which can also ascertain the relative softness of the
resulting fabric or article.
The lower modulus of PTT fibers over PET fibers is explained on a molecular level by the
lower crystalline modulus of PTT. 	The odd number of carbon atoms in the tri-methylene
constituent of PTT results in different chain conformations for PTT as compared to PET.
PTT conformation is more helical or spring like, whereas PET is straighter like a wire.
Naturally, more force is needed to deform a straight wire while very little force is required to
deform a coil spring to the same extent, therefore, PTT with coil spring structure has a very
low crystal modulus, 2.5 GPa vs. 107 GPa (ref 5) for PTT and PET crystals, respectively.
As a result, the crystals of PTT are relatively weaker and easier to bend compared to PET, and
the fiber made from this polymer has lower modulus.
9

Evidence of this different crystalline modulus caused by molecular structure differences is
apparent also in the higher glass transition temperatures (Tg) and crystalline melting
temperatures (Tm) of PET vs. PTT. These higher temperatures generally correspond to stiffer
molecular structures. See Table 3 below:
Table 3: Differences in physical properties of PTT and PET (ref. 4)
Physical properties of PTT vs. PET
PTT 	PET
Tm (°C) 	228 	255
Tg (° C) 	50 	75
Young’s modulus is yet another measure of the relative hardness of a material, and from the
data in Figure 5 it is readily apparent that PTT has far lower modulus than PET.
made from PET, nylon 66, and PTT. 	This graph shows that the properties of PTT polymer
result in fibers of PTT which have lower modulus than fibers made from either PET or nylon
66.
Figure 5. 	Young’s modulus of PET and PTT fibers (ref 5)
Finally, Figure 6 shows a stress (force) vs. strain (fiber deformation) comparison of fibers
10

Figure 6. Modulus of PET and PTT Fibers vs. Nylon 6,6 (ref 5)
0
1
2
3
4
5
6
Stress g/den.
N66
PET
PTT	PTT	PTT
0 	10 	20 	30 	40 	50
Strain, %
As a result of the lower modulus of the PTT fibers, carpets made from PTT fibers are
perceived to be softer, and apparel fabrics made from PTT fibers have greater softness and
superior “hand”.
(c) Stretch with Recovery
Stretch and recovery of fiber is important in apparel applications in order to improve the
comfort of garments and increase their ability to retain their shape and appearance.
Elastic recovery is measured by first extending the fiber in a tensile tester to a given strain
(percent of extension) and then holding the fiber at that position for a given time, after which
time the strain is completely released. 	After a fixed period of relaxation time, the fiber is re-
extended and released to measure its recovery again. 	The difference between these two
extensions and recoveries represents the immediate recoverability of the fiber and the
permanent set. 	More elastic fibers recover immediately with lower permanent set. 	The
terms are further defined in Figure 7.
11

Figure 7. 	Elastic extension and recovery terminology (ref 5)
As shown in Section 2(a) above, the crystalline region of the PET polymer will absorb only a
limited amount of strain. Strain beyond that point will cause the fiber to deform irreversibly.
In the case of PTT, the strain is absorbed by the crystal structure uncoiling like a spring.
When the strain is released, the crystalline structure recovers. 	This difference is shown in
Figure 8 which compares the stretch and recovery performance of PET and PTT fibers. The
data indicates that PTT fiber can be stretched with total recovery more than five times the
stretch after which PET fails to recover.
12

Figure 	8. 	Stretch 	with 	recovery 	of 	PET 	and 	PTT 	fibers 	(ref 	5)
PET
PTT
Section 3. 	The properties of fibers made from PTT described in Section 2 above cause
PTT fibers to be suitable for carpet and apparel applications for which other fibers
marketed under the established generic name polyester would be significantly less well
suited.
As discussed above, the attributes of durability/resilience and softness are of greater
importance to consumers when purchasing residential carpet. 	For apparel applications,
softness and stretch with recovery are among the most important attributes of any fabric. The
test results set forth below illustrate the improved performance of PTT fibers over PET fibers
with respect to these attributes. Each test is preceded by a description of the protocol, and the
identity of the company performing the test.
a) Durability/Resilience
Carpet durability and resilience can be measured by a number of standard tests. For example,
there are simple floor walking tests, where a sample of carpet is placed in a high traffic
location and the number of walkers is simply counted using an electric eye trigger. 	Another
13

Sorona
test, called the Hexapod Wear Test is an appearance retention test endorsed by the Carpet and
Rug Institute (CRI). 	It follows a defined accelerated fatigue process developed through
studies conducted by CRI’s Performance Standards Committee which simulates the most
aggressive parts of a walking action. These samples’ appearance retention is then assessed
according to a defined protocol vs. its "newness" look, where 5 = no change and 1 = severe
change.
Set forth in Figures 9, 10 and 11 below are the results of the Hexapod Wear Test conducted
by Mohawk at its industry certified lab in Lyerly, Georgia on three carpet samples consisting
of carpets of identical constructions9 made from nylon fiber, PET fiber, and PTT fiber. Tests
were performed after 12K cycles, 24K cycles, and 36K cycles. These tests reveal that carpet
made from PTT fibers perform better than carpet made from PET fibers. The performance of
PTT is equal to the performance of nylon, which has been the performance standard for
consumer carpet prior to the introduction of PTT. 	Such performance continues over time as
demonstrated by this industry standard accelerated wear test.
Figure 9: 	Hexapod Wear Test (12K Cycles)
Carpet
Hex. 12K
PET	Nylon
4.5
4.0
3.5
3.0
2.5
Individual Value Plot of Hex. 12K vs Carpet
PTT
There are statistically significant differences between PET, and both PTT and nylon. PTT’s
performance continues to be like nylon, rather than PET polyester. The differences
between PTT and nylon are not statistically significant.
9 See appendix for test carpet constructions
14

Sorona
Sorona
Figure 10: 	Hexapod Wear Test (24K Cycles)
Carpet
Hex. 24K
PET	Nylon
4.5
4.0
3.5
3.0
2.5
2.0
1.5
Individual Value Plot of Hex. 24K vs Carpet
PTT
After 24K cycles, there continue to be statistically significant differences between PET,
and both PTT and nylon. PTT’s performance continues to be like nylon. The differences
between PTT and nylon are not statistically significant.
Figure 11: 	Hexapod Wear Test (36K Cycles)
Carpet
Hex. 36K
PET	Nylon
4.0
3.5
3.0
2.5
2.0
1.5
1.0
Individual Value Plot of Hex. 36K vs Carpet
PTT
After 36K cycles, statistically significant differences continue between PET, and both PTT
and nylon. PTT’s performance remains like nylon. The differences between PTT and
nylon are not statistically significant.
While hexapod test data simulates wear through a mechanical device, PTT’s advantages over
PET are equally apparent when carpet is walked on by human subjects. The performance of
nylon, PET, and PTT carpet in this test is compared by measuring the appearance of carpet
after a certain numbers of cycles (human footsteps on carpet). Results of this test conducted
at an industry certified testing lab operated by Mohawk at Lyerly, Georgia after 20 thousand,
15

Sorona
40 thousand and 60 thousand cycles are set forth below in Figures 12, 13, and 14. Consistent
with the results from the hexapod test, the performance of PTT carpet was much better than
the performance of PET carpet and was comparable to the performance of nylon carpet.
Figure 12: Performance Appearance Rating (20K Cycles)
Carpet
PAR 20K
PET	Nylon
4.5
4.0
3.5
3.0
2.5
2.0
Individual Value Plot of PAR 20K vs Carpet
PTT
There are statistically significant differences between PET, and both PTT and nylon.
In other words, PTT’s performance in this test is like nylon, rather than polyester. The
differences between PTT and nylon are not statistically significant.
16

After 40K cycles, there are also statistically significant differences between PET, and both
Sorona and nylon. Again, Sorona s performance in this test is like nylon, rather than
polyester. The differences between Sorona and nylon are not statistically significant.
Sorona
S orona
After 60K cycles, there are also statistically significant differences between PET, and both
Sorona and nylon. Sorona’s performance continues to be like nylon, rather than
polyester. The differences between Sorona and nylon are not statistically significant.
Figure 13: 	Performance Appearance Rating (40K Cycles)
’
Carpet
PAR 40K
PET	Nylon
4.0
3.5
3.0
2.5
2.0
1.5
Individual Value Plot of PAR 40K vs Carpet
PTT
After 40K cycles, there are also statistically significant differences between PET, and both PTT and
nylon. Again, PTT’s performance in this test is like nylon, rather than polyester. The difference
between PTT and nylon are not statistically significant.
Figure 14: Performance Appearance Rating (60K Cycles)
Carpet
PAR 60K
PET	Nylon
4.0
3.5
3.0
2.5
2.0
1.5
Individual Value Plot of PAR 60K vs Carpet
PTT
After 60K cycles, there are also statistically significant differences between PET, and both
nylon and PTT. PTT’s performance continues to be like nylon, rather than polyester. The
differences between PTT and nylon are not statistically significant.
The data in Figures 15(a) and 15(b) is provided as additional confirmation of the superior
durability and resiliency of even low denier per filament (dpf), soft PTT fiber as compared to
17

identical PET fiber. Shell Chemical LP, acting under contract as the marketing and technical
service provider to PTT Canada, arranged to have identical PTT and PET carpets made and
tested. The bulked continuous filament (BCF) yarns were made on a commercial extruder at
CAF Extrusion, Inc. in Calhoun, Georgia. 	The same spinneret with 120 holes was used for
both yarns resulting in 12 dpf PTT and PET yarns. These yarns were then each twisted at 5
turns-per-inch (TPI), Superba heat-set, and converted into carpet. 	Durability and resiliency
testing was conducted at the certified laboratory of Independent Textile Testing Service, Inc.
(ITTS) in Dalton, Georgia. The carpet specifications are shown in Table 4 below; each point
is the average of three ‘raters’.
Table 4: Head-to-head comparison of PTT vs PET carpets
Carpet Construction Details 	25-ounce per square 35-ounce 	per 	square
yard 	yard
PTT 	PET 	PTT 	PET
Gauge 	5/32 	5/32 	3/16 	3/16
Pile Height (inches) 	13/32 	13/32 	3/4 	3/4
Stitches per Inch (SPI) 	10 	10 	10 	10
Wear Performance
20 K Cycle Walk Test 	3.5 	2.7 	3.9 	3.0
12 K Cycle Hexapod 	3.4 	1.8 	4.0 	3.2
Figure 15(a) : Hexapod Wear Test – 25 Oz Per SqYd (opsy) carpet, 12K cycles
18

Figure 15(b) : Hexapod Wear Test – 35-Oz Per SqYd (opsy) carpet, 12K cycles
b) Softness
Softness is an aesthetic that is valued particularly for apparel fabrics, where skin contact is
prevalent. Softness in carpet, on the other hand, is not associated with direct skin contact. In
both cases, softness is impacted by the ease in which yarns can bend. 	While fabric and carpet
construction differences can vary widely, articles constructed similarly from different fibers
or yarns have softness values that reflect the differences in their constituent polymers. 	A
very useful measure of this difference in yarn softness is the force or stress required to deflect
or strain the fiber a given distance. 	Therefore the stress vs. strain curves for fibers made from
different polymers correlates well with expected fabric softness aesthetics. 	Figure 16 (as
shown on the following two pages) represents first the stress vs. strain performance of PET
and PTT fibers as compared to nylon 66 using 56 dtex yarns, and second a measure of relative
softness by showing a comparison of the force to deflect these same yarns a given distance.
19

Figure 16: 	Stress vs. Strain and Softness measurements 	(cn/dtex and gms force) of
PET, 	N6,6 	and 	PTT 	yarns 	(ref 	http://www.solotex.co.jp/en/soft.html)
PET
Nylon 66
PTT
20

PTT 	Nylon 66	PET
21

c) Stretch with recovery
The superior stretch and recovery properties of fabrics knitted or woven from PTT compared
to fabrics made with PET is demonstrated by the following tests conducted for PTT Canada
by Shell Chemical:
Knitted Fabrics
Knitted fabrics with identical constructions made from draw-textured PET and PTT yarns
were dyed and heat-set according to widely used industry protocols. 76/32 PET yarns were
compared to 78/32 PTT yarns. The PTT was disperse dyed at atmospheric boil and finished at
150°C while the PET fabric was dyed at 130°C and finished at 180°C. 	The two knitted
fabrics were also softened with equal amount of silicone softener.
Figure 17 (a) shows the % fabric elongation at 10 N force and Figure 17 (b) show the %
permanent deformation after one cycle loading. 	Even though the PET fabric has slightly
higher elongation characteristics (an artifact of the fabric construction as explained below) the
PTT fabric has better recover and thus lower set than the PET fabric.
Figure 17: (a) % Elongation performance for fabrics @ 10 N force; (b) % Permanent
set for fabrics after elongation @ 10 N force (ref 6)
130
140
150
160
170
180
190
% Elongation
0
2
4
6
8
10
% Permanent Set
PTT 	PET 	PTT 	PET
78/32 	76/32 	78/32 	76/32
Woven Fabrics
The PET and PTT yarns used for comparing woven fabrics were 72/36 and 78/22
respectively. 	The number of picks/cm used for the PTT fabric was 40 while only 31
picks/cm were used for the PET fabric, which explains the slightly higher elongation.
Both fabrics were woven with a 2/1 construction. 	Since commercial PET draw-textured
yarns were used in the woven fabrics evaluation, there were some differences in the yarn
counts, which must be taken into account when comparing the stretch and recovery of the
fabrics.
Figure 18 shows the % stretch of these fabrics in the weft direction with 10 N load, and
the permanent set after one cycle loading. The PTT woven fabric has high stretch of 22.5
compared to the 8% stretch of the PET fabric. Both fabrics have <5% permanent set after
one cycle loading.
22

Figure 18: % Elongation in the weft direction of PET and PTT woven fabrics (ref 6)
40
30
20
10
0
PET 	PTT
Other Information Relevant To This Petition
Subclass Definition
Applicants propose the following definition for a new subclass of polyester at 16 C.F.R.
303.7(c):
"[a] manufactured fiber in which the fiber-forming substance is any long chain
synthetic polymer composed of at least 85% by weight of an ester of a substituted
aromatic carboxylic acid, including but not restricted to substituted terephthalate units,
[formula omitted] and para substituted hydroxy-benzoate units, [formula omitted] and
where specifically the glycol used to form the ester consists of at least ninety mole
percent 1,3-propanediol."
This definition is appropriate because if a polymer manufacturer uses the above proportions of
starting materials, the resultant polymer will exhibit a molecular or crystalline structure that
will permit fiber extruded from such polymer to exhibit the properties described in this
petition.
Extent of Commercialization of PTT Fibers
PTT has been commercialized by E. I. du Pont de Nemours and Company and PTT Canada.
Carpet fiber spun from PTT has been commercialized by Mohawk Industries (including Lees
Carpets), Shaw Industries and CAF Extrusions. 	Apparel fibers spun from PTT have been
commercialized by the following firms mills grouped according to apparel type:
% Elongation
23

PTT apparel fiber mills grouped by apparel type
• 	Swimwear
O-Sung, Houndey, Haitian
• 	Active Sportswear
Everest, Favis, Yon-Il K, FETL, Shanghai Challenge
• 	Casual Shirts and Pants
Akore, Huvis, Visionland, Chia Her, Wujiang Jili
• 	Casual Shirts
O-Sung, Samil
• 	Jackets and Pants
Saehan, Ulhwa
• 	Ready to Wear
New Wide, True Way, Haitian, Fountain Set
• 	Luggage/Backpacks
Rueyhwa, Tay Shin
Suggested Names For A New Subclass of Polyester Fiber Than May Be Used With
Respect To Fibers Spun From PTT
As indicated above, Petitioners propose in order of preference:
1. triexta; 2. resisoft; and 3. durares.
as possible generic names for a new subclass of PTT fibers.
Petitioners have done word searches for each of these proposed generic subclass names and
have found no confusingly similar use of these names by any other company either as a
trademark or product name.
Petitioners note the Commission’s choice of “PTT001” as a temporary designation.
Recycling Properties
Recycling of man-made fibers, while of secondary importance for consumers in the United
States at this time, will assume increasing importance as consumers increasingly adopt
preferences for sustainable products. 	To the extent that PET and PTT are included in the
same pool of polymer to be recycled because they are currently both classified as polyester,
mixing of the two types of polyester could have adverse effects on the properties of the
recycled polymer (melt temperature and tenacity) and will require different safe handling
24

procedures during processing. 	For this reason, the use of a different generic that would
facilitate the separation of the polymers during recyling is an important consideration.
Figure 20: impact of mixing waste PET and PTT on melting temperature of the polymer
(ref7)
300
250
Melting Point,
 oC
200
150
100
50
0
0 	20 	40 	60 	80 	100
Mole % PTT
Figure 21: 	tenacity of PET fibers melt blended with PTT(ref8)
0
5
10
15
20
25
30
35
40
45
Tenacity (cN/tex)
0 	20 	40 	60 	80 	100
% PTT
25

Finally, the major byproduct produced during the processing of PET is acetaldehyde. 	The
major byproduct produced during the processing of PTT is acrolein. 	These gases have
different properties and quite different OSHA 8 hour personal exposure limits and short-term
exposure limits. Since firms involved in recycling articles made from PET vs. PTT should be
aware of these differences, a new generic name for PTT is appropriate.
Questions regarding this petition may be addressed to:
Carl G. Bartholomaus, Corporate Counsel
DuPont Company
Building 23-2128
Barley Mill Plaza
Wilmington, DE 19880-0023
302-992-3207
Carl.G.Bartholomaus@usa.dupont.com
Respectfully submitted:
Mohawk Industries, Inc.
By _____________________________
PTT Poly Canada
By _____________________________
E. I. du Pont de Nemours and Company
By _____________________________
26

References
1. 	I. J. Desborough, I. H. Hall, and J. Z. Neisser, The Structure of Poly(trimethylene
terephthalate), Polymer, 20, 545 (1979)
2. 	R. Jakeways, I. M. Ward, and M. A. Wildings, Crystal Deformation in Aromatic Polyesters, J.
Polym. Sci., Phys. Ed., 12, 799 (1975)
3. 	H.H. Chuah, Synthesis, Properties and Applications of Poly(Trimethylene Terephthalate)
in Schiers, J. and Long, T.E. ed., Modern Polyesters: Chemistry and Technology of
Polyesters and Copolyesters, Chapter 11, pp. 361-391, John Wiley, 2003.
4. 	I. Goodman, “Encyclopedia of Polymer Science”, Vol. 11, New York: J. Wiley and Sons,
1969
5. 	I.M. Ward, M.A. Wilding and H. Brody, The Mechanical Properties and Structure of Poly
(m-methylene Terephthalate) Fibers, J. Polym. Sci., Polym. Phys. Ed., 14, 263 (1976).
6. 	M. Moerman and G. Hess, Corterra Polymers, Value Proposition in TextileApparel
Applications, Technical Bulletin, SC-3014-00, Shell Chemical-Company, 2000.
7. 	E. Punusamy and T. Balakrishnan, Macromol. Sci., Chem., A22(3), 373(1985).
8. 	W. Opperman, P. Hirt and C. Fritz, Chem. Fibers Int., 49, 33
27

CARPETS USED FOR PERFORMANCE TESTS
wt. 	gauge 	denier 	dpf 	polymer 	ply twist 	tpi 	Stain Blocker
oz/yd 2
35 	3/16 	1480 	18 	PTT 	1 x 1 	5.5 	No
45 	3/16 	1480 	18 	PTT 	1 x 1 	5.5 	No
55 	3/16 	1480 	18 	PTT 	1 x 1 	5.5 	No
50 	1/8 	1480 	18 	PTT 	1 x 1 	5.5 	No
40 	1/8 	1480 	18 	PTT 	1 x 1 	5.5 	No
60 	1/8 	1480 	18 	PTT 	1 x 1 	5.5 	No
32 	3/16 	1480 	18 	PTT 	1 x 1 	5.5 	No
42 	3/16 	1480 	18 	PTT 	1 x 1 	5.5 	No
52 	3/16 	1480 	18 	PTT 	1 x 1 	5.5 	No
42 	3/16 	1480 	18 	PTT 	1 x 1 	5.5 	No
32 	3/16 	1480 	18 	PTT 	1 x 1 	5.5 	No
52 	3/16 	1480 	18 	PTT 	1 x 1 	5.5 	No
32 	3/16 	1480 	18 	PTT 	1 x 1 	5.5 	No
35 	3/16 	995 	12 	Nylon 	2 x 2 	6.5 x 1 	Yes
40 	3/16 	995 	12 	Nylon 	2 x 2 	6.5 x 1 	Yes
50 	3/16 	995 	12 	Nylon 	2 x 2 	6.5 x 1 	Yes
35 	3/16 	995 	12 	Nylon 	2 x 2 	6.5 x 1 	Yes
52 	3/16 	995 	12 	Nylon 	2 x 2 	6.5 x 1 	Yes
38 	3/16 	995 	12 	Nylon 	2 x 2 	6.5 x 1 	Yes
35 	3/16 	995 	12 	Nylon 	2 x 2 	6.5 x 1 	Yes
38 	3/16 	995 	12 	Nylon 	2 x 2 	6.5 x 1 	Yes
35 	3/16 	995 	12 	Nylon 	2 x 2 	6.5 x 1 	Yes
55 	1/10 	1045 	12 	Nylon 	1 x 1 	6.5 	Yes
46 	1/8 	1045 	12 	Nylon 	1 x 1 	5.25 	Yes
35 	1/8 	1045 	12 	Nylon 	1 x 1 	5.5 	Yes
65 	1/10 	1045 	12 	Nylon 	1 x 1 	6.5 	Yes
46 	5/32 	1045 	12 	Nylon 	1 x 1 	6.5 	Yes
34 	3/16 	1460 	15 	PET 	1 x 1 	5.5 	No
40 	3/16 	1460 	15 	PET 	1 x 1 	5.5 	No
51 	3/16 	1460 	15 	PET 	1 x 1 	5.5 	No
51 	3/16 	1460 	15 	PET 	1 x 1 	5.5 	No
40 	3/16 	1460 	15 	PET 	1 x 1 	5.5 	No
32 	3/16 	1460 	15 	PET 	1 x 1 	5.5 	No
40 	3/16 	1459 	15 	PET 	1 x 1 	5.5 	No
52 	1/8 	3.0 cc 	15 	PET Staple 	1 x 1 	4.8 x 4.0 	No
42 	1/8 	3.0 cc 	15 	PET Staple 	1 x 1 	4.8 x 4.0 	No
35 	3/16 	3.15 cc 	15 	PET Staple 	1 x 1 	5.3 x 6.4 	No
58 	5/32 	3.0 cc 	15 	PET Staple 	1 x 1 	4.8 x 4.0 	No
Appendix A: Carpets used for performance tests
28