U.S. patent application number 12/629379 was filed with the patent office on 2010-06-10 for container and composition for enhanced gas barrier properties.
This patent application is currently assigned to THE COCA-COLA COMPANY. Invention is credited to T. Edwin Freeman, Xiaoyan Huang, Robert Kriegel, Robert Schiavone.
Application Number | 20100143546 12/629379 |
Document ID | / |
Family ID | 42231370 |
Filed Date | 2010-06-10 |
United States Patent
Application |
20100143546 |
Kind Code |
A1 |
Kriegel; Robert ; et
al. |
June 10, 2010 |
CONTAINER AND COMPOSITION FOR ENHANCED GAS BARRIER PROPERTIES
Abstract
A container comprising a polyester composition with enhanced
carbon dioxide and oxygen barrier properties is provided. The
polyester composition comprises a polyester and a gas barrier
enhancing additive. In a particular embodiment, the gas barrier
enhancing additive comprises a compound having the chemical
formula:
X--(X.sup.1).sub.s--COO--(X.sup.2).sub.t--X.sup.3--(X.sup.4).sub.u--OOC--
-(X.sup.5).sub.v--X.sup.6 or
X--(X.sup.1).sub.s--OOC--(X.sup.2).sub.t--X.sup.3--(X.sup.4).sub.u--COO--
-(X.sup.5).sub.v--X.sup.6
Inventors: |
Kriegel; Robert; (Decatur,
GA) ; Huang; Xiaoyan; (Marietta, GA) ;
Schiavone; Robert; (Matthews, NC) ; Freeman; T.
Edwin; (Woodstock, GA) |
Correspondence
Address: |
SUTHERLAND ASBILL & BRENNAN LLP
999 PEACHTREE STREET, N.E.
ATLANTA
GA
30309
US
|
Assignee: |
THE COCA-COLA COMPANY
Atlanta
GA
|
Family ID: |
42231370 |
Appl. No.: |
12/629379 |
Filed: |
December 2, 2009 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61121036 |
Dec 9, 2008 |
|
|
|
Current U.S.
Class: |
426/106 ;
428/36.6; 524/109; 524/293 |
Current CPC
Class: |
C08K 5/10 20130101; B65D
85/72 20130101; C08K 5/103 20130101; B29L 2031/7158 20130101; B29K
2105/0005 20130101; C08K 5/10 20130101; C08K 2201/008 20130101;
C08K 5/12 20130101; B29K 2995/0067 20130101; C08K 5/12 20130101;
Y10T 428/1379 20150115; B65D 1/0207 20130101; C08K 5/103 20130101;
B29C 49/08 20130101; B29K 2067/003 20130101; C08K 5/1539 20130101;
C08K 5/1535 20130101; C08L 67/02 20130101; C08L 67/02 20130101;
C08L 67/02 20130101 |
Class at
Publication: |
426/106 ;
428/36.6; 524/293; 524/109 |
International
Class: |
B32B 27/18 20060101
B32B027/18; B65D 85/72 20060101 B65D085/72; B32B 1/02 20060101
B32B001/02; B32B 27/36 20060101 B32B027/36; C08K 5/12 20060101
C08K005/12; C08K 5/1535 20060101 C08K005/1535 |
Claims
1. A container comprising a polyester composition comprising a
polyester and a gas barrier enhancing additive, wherein the gas
barrier enhancing additive comprises a compound having the chemical
structure of Formula I or Formula II: ##STR00068## wherein X and
X.sup.6, independent of one another, comprise hydrogen, halide,
heteroatom, hydroxyl, amino, amido, alkylamino, arylamino, alkoxy,
aryloxy, nitro, acyl, cyano, sulfo, sulfato, mercapto, imino,
sulfonyl, sulfenyl, sulfinyl, sulfamoyl, phosphonyl, phosphinyl,
phosphoryl, phosphino, thioester, thioether, anhydride, oximno,
hydrazino, carbamyl, phosphonic acid, phosphonato, or a
C.sub.1-C.sub.10 monovalent hydrocarbon which is unsubstituted or
substituted with one or more functional moieties; wherein X.sup.1,
X.sup.2, X.sup.3, X.sup.4, and X.sup.5, independent of one another,
comprise a heteroatom or a C.sub.1-C.sub.10 divalent hydrocarbon,
wherein each heteroatom or C.sub.1-C.sub.10 divalent hydrocarbon is
unsubstituted or substituted with one or more functional moieties
or one or more C.sub.1-C.sub.10 hydrocarbyls that are unsubstituted
or substituted with one or more functional moieties; and wherein s,
t, u, and v, independent of one another, is a number from 0 to 10;
wherein when X.sup.3 comprises a C.sub.6 or C.sub.10 divalent
aromatic hydrocarbon, X and X.sup.6, independent of one another,
comprise a hydrogen, halide, heteroatom, hydroxyl, amino, amido,
alkylamino, arylamino, alkoxy, aryloxy, nitro, acyl, cyano, sulfo,
sulfato, mercapto, imino, sulfonyl, sulfenyl, sulfinyl, sulfamoyl,
phosphonyl, phosphinyl, phosphoryl, phosphino, thioester,
thioether, anhydride, oximno, hydrazino, carbamyl, phosphonic acid,
phosphonato, or a C.sub.3-C.sub.10 monovalent cyclic or
heterocyclic non-aryl hydrocarbon that are unsubstituted or
substituted with one or more functional moieties.
2. The container of claim 1, wherein the gas barrier additive
comprises a compound having the chemical structure of Formula I,
wherein X and X.sup.6 each comprise a phenyl group.
3. The container of claim 1, wherein the gas barrier additive
comprises a compound having the chemical structure of Formula I,
wherein X and X.sup.6 each comprise a phenyl group and s, t, u and
v are 0.
4. The container of claim 1, wherein the gas barrier additive
comprises a compound having the chemical structure of Formula I,
wherein X and X.sup.6 each comprise a phenyl group, s, t, u and v
are 0, and X.sup.3 comprises a divalent hydro bi-furan, the gas
barrier additive comprising a compound having the chemical
structure: ##STR00069##
5. The container of claim 1, wherein the gas barrier additive
comprises a compound having the chemical structure of Formula I,
wherein X and X.sup.6 each comprise a phenyl group, s and v are 0,
t and u are 1, X.sup.2 and X.sup.4 each comprise a divalent C.sub.1
hydrocarbon, and X.sup.3 comprises a divalent cyclohexane, the gas
barrier additive comprising a compound having the chemical
structure: ##STR00070##
6. The container of claim 1, wherein the gas barrier additive
comprises a compound having the chemical structure of Formula I,
wherein X and X.sup.6 each comprise a naphthyl group.
7. The container of claim 1, wherein the gas barrier additive
comprises a compound having the chemical structure of Formula I,
wherein X and X.sup.6 each comprise a naphthyl group and s and v
are 0.
8. The container of claim 1, wherein the gas barrier additive
comprises a compound having the chemical structure of Formula I,
wherein X and X.sup.6 each comprise a naphthyl group, s and v are
0, t and u are 1, and X.sup.2 and X.sup.4 each comprise a divalent
C.sub.1 hydrocarbon.
9. The container of claim 1, wherein the gas barrier additive
comprises a compound having the chemical structure of Formula I,
wherein X and X.sup.6 each comprise a naphthyl group, s and v are
0, t and u are 1, X.sup.2 and X.sup.4 each comprise a divalent
C.sub.1 hydrocarbon, and X.sup.3 comprises a divalent cyclohexane,
the gas barrier additive comprising a compound having the chemical
structure: ##STR00071##
10. The container of claim 1, wherein the gas barrier additive
comprises a compound having the chemical structure of Formula I,
wherein X and X.sup.6 each comprise a cyclohexyl group.
11. The container of claim 1, wherein the gas barrier additive
comprises a compound having the chemical structure of Formula II,
wherein X and X.sup.6 each comprise a cyclohexyl group and s and v
are 0.
12. The container of claim 1, wherein the gas barrier additive
comprises a compound having the chemical structure of Formula II,
wherein X and X.sup.6 each comprise a cyclohexyl group and s, t, u,
and v are 0.
13. The container of claim 1, wherein the gas barrier additive
comprises a compound having the chemical structure of Formula II,
wherein X and X.sup.6 each comprise a cyclohexyl group, s, t, u,
and v are 0, and X.sup.3 comprises a divalent benzene, the gas
barrier additive comprising a compound having the chemical
structure: ##STR00072##
14. The container of claim 13, wherein the divalent benzene is
meta-substituted, the gas barrier additive comprising a compound
having the chemical structure: ##STR00073##
15. The container of claim 13, wherein the divalent benzene is
para-substituted, the gas barrier additive comprising a compound
having the chemical structure: ##STR00074##
16. The container of claim 1, wherein the gas barrier additive
comprises a compound having the chemical structure of Formula II,
wherein X and X.sup.6 each comprise a cyclohexyl group, s, t, u,
and v are 0, and X.sup.3 comprises a divalent naphthalene, the gas
barrier additive comprises a compound having the chemical
structure: ##STR00075##
17. The container of claim 16, wherein the divalent naphthalene is
substituted at the 2 and 6 positions, the gas barrier additive
comprising a compound having the chemical structure:
##STR00076##
18. The container of claim 1, wherein the gas barrier additive
comprises a compound having the chemical structure of Formula II,
wherein X and X.sup.6 each comprise a benzoate group.
19. The container of claim 1, wherein the gas barrier additive
comprises a compound having the chemical structure of Formula II,
wherein X and X.sup.6 each comprise a benzoate group and t and u
are 0.
20. The container of claim 1, wherein the gas barrier additive
comprises a compound having the chemical structure of Formula II,
wherein X and X.sup.6 each comprise a benzoate group, t and u are
0, s and v are 1, and X.sup.1 and X.sup.5 each comprise a divalent
C.sub.1 hydrocarbon.
21. The container of claim 1, wherein the gas barrier additive
comprises a compound having the chemical structure of Formula II,
wherein X and X.sup.6 each comprise a benzoate group, t and u are
0, s and v are 1, and X.sup.1 and X.sup.5 each comprise a divalent
C.sub.1 hydrocarbon, and X.sup.3 is a divalent benzene, the gas
barrier additive comprising a compound having the chemical
structure: ##STR00077##
22. The container of claim 21, wherein the divalent benzene is
para-substituted, the gas barrier additive comprising a compound
having the chemical structure: ##STR00078##
23. The container of claim 1, wherein the gas barrier additive
comprises a compound having the chemical structure of Formula II,
wherein X and X.sup.6 each comprise a benzoate group.
24. The container of claim 1, wherein the gas barrier additive
comprises a compound having the chemical structure of Formula II,
wherein X and X.sup.6 each comprise a benzoate group, s and v are
2, and X.sup.1 and X.sup.5 each comprise a divalent C.sub.1
hydrocarbon.
25. The container of claim 1, wherein the gas barrier additive
comprises a compound having the chemical structure of Formula II,
wherein X and X.sup.6 each comprise a benzoate group, s and v are
2, X.sup.1 and X.sup.5 each comprise a divalent C.sub.1
hydrocarbon, t and u are 1, and X.sup.2 and X.sup.4 each comprise a
divalent benzoate.
26. The container of claim 1, wherein the gas barrier additive
comprises a compound having the chemical structure of Formula II,
wherein X and X.sup.6 each comprise a benzoate group, s and v are
2, X.sup.1 and X.sup.5 each comprise a divalent C.sub.1
hydrocarbon, t and u are 1, X.sup.2 and X.sup.4 each comprise a
divalent benzoate, and X.sup.3 comprises a divalent C.sub.2
hydrocarbon, the gas barrier additive comprising a compound having
the chemical structure: ##STR00079##
27. The container of claim 26, wherein the divalent benzoates are
meta-substituted, the gas barrier additive comprising a compound
having the chemical structure: ##STR00080##
28. The container of claim 1, wherein the gas barrier additive
comprises a compound having the chemical structure of Formula II,
wherein X and X.sup.6 each comprise an aryloxy group.
29. The container of claim 1, wherein the gas barrier additive
comprises a compound having the chemical structure of Formula II,
wherein X and X.sup.6 each comprise an aryloxy group, t and u are
0, and X.sup.3 comprises a divalent benzene.
30. The container of claim 1, wherein the gas barrier additive
comprises a compound having the chemical structure of Formula II,
wherein X and X.sup.6 each comprise a phenoxy group, t and u are 0,
s and v are 1, X.sup.1 and X.sup.5 each comprise a straight-chain
divalent C.sub.2 hydrocarbon, and X.sup.3 comprises a divalent
benzene, the gas barrier additive comprising a compound having the
chemical structure: ##STR00081##
31. The container of claim 30, wherein the divalent benzene is
para-substituted, the gas barrier additive comprising a compound
having the chemical structure: ##STR00082##
32. The container of claim 1, wherein the gas barrier additive is
present in the polyester composition in an amount in the range of
about 0.1 to about 10 weight percent of the polyester
composition.
33. The container of claim 1, wherein the polyester comprises
polyethylene terephthalate.
34. The container of claim 1, wherein the polyester composition
comprises a poly(ethylene terephthalate) based copolymer having
less than 20 percent diacid, less than 10 percent glycol
modification, or both, based on 100 mole percent diacid component
and 100 mole percent diol component.
35. The container of claim 1, wherein the polyester composition
comprises a polyester made using at least one first
polycondensation catalyst selected from the group consisting of
metals in groups 3, 4, 13, and 14 of the Periodic Table and
comprising a catalyst residue remaining in the polyester from
formation of the polyester, the catalyst residue comprising at
least a portion of the at least one first polycondensation
catalyst.
36. The container of claim 1, wherein the polyester composition has
an I.V. from about 0.65 dL/g to about 1.0 dL/g.
37. A packaged beverage comprising a beverage disposed in the
container of claim 1 and a seal for sealing the beverage in the
package.
38. A polyester composition comprising a polyester and a gas
barrier additive, wherein the gas barrier enhancing additive
comprises a compound having the chemical structure of Formula I or
Formula II: ##STR00083## wherein X and X.sup.6, independent of one
another, comprise hydrogen, halide, heteroatom, hydroxyl, amino,
amido, alkylamino, arylamino, alkoxy, aryloxy, nitro, acyl, cyano,
sulfo, sulfato, mercapto, imino, sulfonyl, sulfenyl, sulfinyl,
sulfamoyl, phosphonyl, phosphinyl, phosphoryl, phosphino,
thioester, thioether, anhydride, oximno, hydrazino, carbamyl,
phosphonic acid, phosphonato, or a C.sub.1-C.sub.10 monovalent
hydrocarbon which is unsubstituted or substituted with one or more
functional moieties; wherein X.sup.1, X.sup.2, X.sup.3, X.sup.4,
and X.sup.5, independent of one another, comprise a heteroatom or a
C.sub.1-C.sub.10 divalent hydrocarbon, wherein each heteroatom or
C.sub.1-C.sub.10 divalent hydrocarbon is unsubstituted or
substituted with one or more functional moieties or one or more
C.sub.1-C.sub.10 hydrocarbyls that are unsubstituted or substituted
with one or more functional moieties; and wherein s, t, u, and v,
independent of one another, is a number from 0 to 10; wherein when
X.sup.3 comprises a C.sub.6 or C.sub.10 divalent aromatic
hydrocarbon, X and X.sup.6, independent of one another, comprise a
hydrogen, halide, heteroatom, hydroxyl, amino, amido, alkylamino,
arylamino, alkoxy, aryloxy, nitro, acyl, cyano, sulfo, sulfato,
mercapto, imino, sulfonyl, sulfenyl, sulfinyl, sulfamoyl,
phosphonyl, phosphinyl, phosphoryl, phosphino, thioester,
thioether, anhydride, oximno, hydrazino, carbamyl, phosphonic acid,
phosphonato, or a C.sub.3-C.sub.10 monovalent cyclic or
heterocyclic non-aryl hydrocarbon that are unsubstituted or
substituted with one or more functional moieties.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims benefit of U.S. Provisional
Application No. 61/121,036, filed Dec. 9, 2008. This application is
incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
[0002] This invention relates to a packaged beverage, and more
particularly to enhancing the carbon dioxide and oxygen barrier
properties of a container for a packaged beverage, thereby
increasing the shelf life of its contents, by incorporating an
additive into polyethylene terephthalate (PET) and its
copolyesters.
BACKGROUND
[0003] Polyethylene terephthalate and its copolyesters (hereinafter
referred to collectively as "PET") are widely used to make
containers for carbonated soft drinks, juice, water, and the like
due to their excellent combination of clarity, mechanical, and gas
barrier properties. In spite of these desirable characteristics,
oxygen and carbon dioxide gas barrier properties of PET limit
application of PET for smaller sized packages, as well as for
packaging oxygen sensitive products, such as beer, juice, and tea
products. A widely expressed need exists in the packaging industry
to further improve the gas barrier properties of PET.
[0004] The relatively high permeability of PET to carbon dioxide
limits the use of smaller PET containers for packaging carbonated
soft drinks The permeation rate of carbon dioxide through PET
containers is in the range of 3 to 14 cc's per day or 1.5 to 2
percent per week loss rate at room temperature depending on the
size of the container. A smaller container has a larger surface
area to volume ratio resulting in a higher relative loss rate. For
this reason, PET containers are currently used only as larger
containers for packaging carbonated soft drinks, while metal cans
and glass containers are the choice for smaller carbonated soft
drink containers.
[0005] The amount of carbon dioxide remaining in a packaged
carbonated soft drink determines its shelf life. Normally,
carbonated soft drink containers are filled with approximately four
volumes of carbon dioxide per volume of water. It is generally
accepted that a packaged carbonated soft drink reaches the end of
its shelf life when 17.5 percent of the carbon dioxide in the
container is lost due to permeation of the carbon dioxide through
the container side wall and closure. The permeability of PET to
carbon dioxide therefore determines the shelf life of the packaged
carbonated beverage and thus, the suitability of PET as a packaging
material.
[0006] Numerous technologies have been developed or are being
developed to enhance the barrier of PET to small gas molecules, but
some are too expensive and others may cause undesirable change in
PET mechanical properties, stretch ratio, and/or clarity.
[0007] Thus, there is a need in the art to enhance the barrier
performance of PET for use in applications that will require
enhanced barrier, such as in the packaging of carbonated beverages
and oxygen sensitive beverages and foods, in a manner that does not
cause substantial degradation of the PET mechanical properties,
does not substantially impact the stretch ratio of the PET, and/or
does not negatively impact the clarity of the PET.
SUMMARY
[0008] The embodiments provided herein address the above-described
needs by providing a polyester container with enhanced gas barrier
properties. The polyester container comprises a polyester
composition comprised of a polyester and a gas barrier enhancing
additive. In an embodiment, the gas barrier enhancing additive
comprises a compound having the chemical structure of Formula I or
Formula II:
##STR00001##
[0009] wherein X and X.sup.6, independent of one another, comprise
hydrogen, halide, heteroatom, hydroxyl, amino, amido, alkylamino,
arylamino, alkoxy, aryloxy, nitro, acyl, cyano, sulfo, sulfato,
mercapto, imino, sulfonyl, sulfenyl, sulfinyl, sulfamoyl,
phosphonyl, phosphinyl, phosphoryl, phosphino, thioester,
thioether, anhydride, oximno, hydrazino, carbamyl, phosphonic acid,
phosphonato, or a C.sub.1-C.sub.10 monovalent hydrocarbon which may
be unsubstituted or substituted with one or more functional
moieties;
[0010] wherein X.sup.1, X.sup.2, X.sup.3, X.sup.4, and X.sup.5,
independent of one another, comprise a heteroatom or a
C.sub.1-C.sub.10 divalent hydrocarbon, wherein each heteroatom or
C.sub.1-C.sub.10 divalent hydrocarbon may be unsubstituted or
substituted with one or more functional moieties or one or more
C.sub.1-C.sub.10 hydrocarbyls that may be unsubstituted or
substituted with one or more functional moieties; and
[0011] wherein s, t, u, and v, independent of one another, may be a
number from 0 to 10;
[0012] wherein when X.sup.3 comprises a C.sub.6 or C.sub.10
divalent aromatic hydrocarbon, X and X.sup.6, independent of one
another, comprise a hydrogen, halide, heteroatom, hydroxyl, amino,
amido, alkylamino, arylamino, alkoxy, aryloxy, nitro, acyl, cyano,
sulfo, sulfato, mercapto, imino, sulfonyl, sulfenyl, sulfinyl,
sulfamoyl, phosphonyl, phosphinyl, phosphoryl, phosphino,
thioester, thioether, anhydride, oximno, hydrazino, carbamyl,
phosphonic acid, phosphonato, or a C.sub.3-C.sub.10 monovalent
cyclic or heterocyclic non-aryl hydrocarbon which may be
unsubstituted or substituted with one or more functional
moieties.
[0013] According to another embodiment, a method for enhancing gas
barrier properties of a polyester container is provided, the method
comprising blending a polyester with such a gas barrier enhancing
additive to form a polyester composition. According to particular
embodiments, the polyester composition can be formed into articles
such as a container.
[0014] Furthermore, in another embodiment, the step of forming the
container comprises stretch blow molding. Particular embodiments
provide polyester containers, such as PET containers, with enhanced
gas barrier, and in particular, enhanced gas barrier to carbon
dioxide and oxygen. This makes certain embodiments particularly
suited for packaging carbonated soft drinks and oxygen sensitive
beverages and foods. Particular embodiments may achieve this
enhanced gas barrier while maintaining acceptable physical
properties and clarity.
[0015] Other objects, features, and advantages of this invention
will become apparent from the following detailed description,
drawings, and claims.
BRIEF DESCRIPTION OF DRAWINGS
[0016] FIG. 1 is a schematic diagram of a system for making a PET
container with enhanced gas barrier in accordance with an
embodiment.
[0017] FIG. 2 is a sectional elevation view of a molded container
preform made in accordance with an embodiment.
[0018] FIG. 3 is a sectional elevation view of a blow molded
container made from the preform of FIG. 2 in accordance with an
embodiment.
[0019] FIG. 4 is a perspective view of a packaged beverage made in
accordance with an embodiment.
[0020] FIG. 5 is a schematic illustration of a process for the
production of an enhanced gas barrier additive in accordance with
an embodiment.
[0021] FIG. 6 is a schematic illustration of a process for the
production of an enhanced gas barrier additive in accordance with
an embodiment.
[0022] FIG. 7 is a graph illustrating the percent average bottle
creep for blow molded containers made in accordance with an
embodiment.
DETAILED DESCRIPTION
[0023] A polyester container with enhanced gas barrier properties
and a method for making a polyester container with enhanced gas
barrier properties are provided herein. Generally described, the
polyester container comprises a polyester composition comprising a
polyester and a gas barrier enhancing additive having the chemical
structure of Formula I or Formula II:
##STR00002##
[0024] wherein X and X.sup.6, independent of one another, comprise
hydrogen, halide, heteroatom, hydroxyl, amino, amido, alkylamino,
arylamino, alkoxy, aryloxy, nitro, acyl, cyano, sulfo, sulfato,
mercapto, imino, sulfonyl, sulfenyl, sulfinyl, sulfamoyl,
phosphonyl, phosphinyl, phosphoryl, phosphino, thioester,
thioether, anhydride, oximno, hydrazino, carbamyl, phosphonic acid,
phosphonato, or a C.sub.1-C.sub.10 monovalent hydrocarbon which may
be unsubstituted or substituted with one or more functional
moieties;
[0025] wherein X.sup.1, X.sup.2, X.sup.3, X.sup.4, and X.sup.5,
independent of one another, comprise a heteroatom or a
C.sub.1-C.sub.10 divalent hydrocarbon, wherein each heteroatom or
which may be unsubstituted or substituted with one or more
functional moieties or one or more C.sub.1-C.sub.10 hydrocarbyls
that may be unsubstituted or substituted with one or more
functional moieties; and
[0026] wherein s, t, u, and v, independent of one another, may be a
number from 0 to 10;
[0027] wherein when X.sup.3 comprises a C.sub.6 or C.sub.10
divalent aromatic hydrocarbon, X and X.sup.6, independent of one
another, comprise a hydrogen, halide, heteroatom, hydroxyl, amino,
amido, alkylamino, arylamino, alkoxy, aryloxy, nitro, acyl, cyano,
sulfo, sulfato, mercapto, imino, sulfonyl, sulfenyl, sulfinyl,
sulfamoyl, phosphonyl, phosphinyl, phosphoryl, phosphino,
thioester, thioether, anhydride, oximno, hydrazino, carbamyl,
phosphonic acid, phosphonato, or a C.sub.3-C.sub.10 monovalent
cyclic or heterocyclic non-aryl hydrocarbon which may be
unsubstituted or substituted with one or more functional
moieties.
[0028] Polyester containers and methods for making such containers
made in accordance with the embodiments provided herein are further
described below and in accompanying FIGS. 1-7.
I. Polyester Composition
[0029] The polyester compositions and containers provided herein
may be applicable to any polyester and may be suitable for uses in
which a high gas barrier is desirable. Non-limiting examples of
suitable polyesters for use in the embodiments provided herein
include PET copolymers, polyethylene naphthalate (PEN),
polyethylene isophthalate, and the like. PET copolymers are
particularly useful because they are used for many barrier
applications, such as films and containers. Suitable containers
include, but are not limited to, bottles, drums, carafes, coolers,
and the like.
[0030] Polyesters, including PET copolymers, have free volume
between the polymer chains. As is known to those skilled in the
art, the amount of free volume in polyesters, such as PET
copolymers, determines their barrier to gas molecules. The lower
the free volume, the lower the gas diffusion, and the higher the
barrier to gas molecules. Desirably, the gas barrier enhancing
additive is at least partially disposed in the free volume of the
polyester between the polyester chains.
[0031] PET copolymers suitable for use in embodiments of this
invention may comprise a diol component having repeat units from
ethylene glycol and a diacid component having repeat units from
terephthalic acid. In particular embodiments, the PET copolymer has
less than 20 percent diacid modification, less than 10 percent
glycol modification, or both, based on 100 mole percent diacid
component and 100 mole percent diol component. Such PET copolymers
are well known.
[0032] The polyester may be made using any suitable
polycondensation catalysts; however, Applicants previously
discovered that specific polycondensation catalysts may be
particularly suited for use with gas barrier enhancing additives.
Such polycondensation catalysts are disclosed in U.S. Patent
Publication No. 2006/0275568. In one embodiment, the polyester may
be made using at least one first polycondensation catalyst selected
from the group consisting of metals in groups 3, 4, 13, and 14 of
the Periodic Table. The polyester composition may comprise a
catalyst residue remaining in the polyester from formation of the
polyester and the catalyst residue may comprise at least a portion
of the at least one first polycondensation catalyst. In some
embodiments, the catalyst residue may be present in the polyester
composition in an amount up to 250 ppm, and is preferably less.
[0033] The gas barrier enhancing additive and the polyester may
undergo a transesterification reaction and thereby cause problems
in container applications, such as lowering the I.V. of the
polyester composition to unacceptable levels. Transesterification
reaction in PET copolymer resin is believed to be catalyzed by the
residual polycondensation catalyst. Accordingly, in one embodiment
the residual polycondensation catalyst in the polyester may be
deactivated. One approach to deactivating these catalysts has been
to add catalyst deactivating compounds, such as phosphorus
containing compounds, to the polyester composition. Once the
catalysts are deactivated, they will not catalyze the
transesterification reaction and such reaction will be slowed down
during the melt processing of the polyester, such as PET copolymer,
and gas barrier enhancing additive blend. The phosphorus containing
compounds include both organic and inorganic compounds. Examples
include but are not limited to phosphoric acid, polyphosphoric
acid, and tris(2,4-di-t-butylphenyl) phosphite, tris
monononylphenyl phosphite.
[0034] The polycondensation catalyst deactivating agent optionally
may be added to the polyester composition in an amount sufficient
to deactivate the polycondensation catalyst residue in the
polyester composition so that the gas barrier enhancing additive is
able to sufficiently enhance the gas barrier properties of the
polyester composition and the resulting polyester container. For
example, these additives may be added to the polyester composition
in amounts less than 2000 ppm. In accordance with one embodiment,
the polycondensation catalyst deactivating agent may be present in
the polyester composition in amount from about 10 to about 500 ppm
by weight of the polyester composition or in an amount from about
100 to about 500 ppm by weight of the polyester composition.
[0035] Despite the addition of the polycondensation deactivating
agents, the extent of the deactivation of the polycondensation
remains unclear and may not be sufficient to eliminate the
degradation of the polyester through reaction with the barrier
enhancing additives when certain polycondensation catalysts are
used in the formation of the polyester by polycondensation
reaction. Accordingly, in other embodiments the polyester
composition may comprise a second polycondensation catalyst
selected from the group consisting of cobalt, antimony, zinc,
manganese, magnesium, cesium, calcium, and cadmium. Those skilled
in the art should appreciate that the amount of the second
polycondensation catalyst which is present in the polyester
composition should be maintained below levels which may
significantly lower the I.V. of the polyester composition below
acceptable levels. Accordingly, in one embodiment the second
polycondensation catalyst may be present in the polyester
composition in an amount up to 3 ppm of the polyester composition.
Specifically, the reactivity of traditional polycondensation
catalysts such as cobalt, antimony, zinc, manganese, magnesium,
cesium, calcium, calcium, and cadmium is not mitigated to the
extent necessary to make use of the phosphorus-based deactivating
agents a viable alternative compared to substantial reduction or
elimination of the metal catalyst residues containing cobalt,
antimony, zinc, manganese, magnesium, cesium, calcium, or
cadmium.
[0036] Reaction between the gas barrier enhancing additive and the
polyester composition can reduce the I.V. of the polyester
composition and resulting container preform. PET with a
significantly lower I.V. cannot be used in blow molding containers,
such as beverage containers, because lower I.V. PET makes
containers with poor mechanical performance, such as creep, drop
impact resistance, and the like. Still further, PET containers made
from lower I.V. PET generally have poor stress cracking resistance
for carbonated soft drink applications, which is undesirable in
container applications. In order to prepare container preforms and
containers with adequate physical properties and an I.V. suitable
for efficient molding of the preforms and blow molding of such
preforms into containers, the polyester composition desirably has
an I.V. of at least 0.65, more preferably from about 0.65 to about
1.0, and even more preferably from about 0.70 to about 0.86. The
units for I.V. herein are all in dL/g measured according to ASTM
D4603-96, in which the I.V. of PET based resin is measured at
30.degree. C. with 0.5 weight percent concentration in a 60/40 (by
weight) phenol/1,1,2,2-tetrachloroethane solution.
[0037] As discussed above, polyester having residual catalysts with
minimal or no cobalt, antimony, zinc, manganese, magnesium, cesium,
calcium, and cadmium substantially alleviates reduction in I.V.
Total cobalt, antimony, zinc, manganese, magnesium, cesium,
calcium, and cadmium content is desirably less than 3 ppm.
According to a particular embodiment, suitable gas barrier
enhancing additives for PET polymers and copolymers are blended
with polyester having titanium and aluminum-based metal catalyst
residues without the presence of residues containing cobalt,
antimony, zinc, manganese, magnesium, cesium, calcium, or cadmium.
The periodicity of the elements in the modern periodic table
suggests that similar chemical reactivity exists throughout a
group. As such, zirconium and halfnium may be useful as analogs for
titanium catalysts, and gallium, indium, and thallium may be useful
analogs of aluminum. Germanium, tin, and lead from group 14 may be
suitable.
[0038] In a particular embodiment, a polyester composition
comprises a polyester and a gas barrier enhancing additive, which
is further described below. The gas barrier enhancing additive of
the polyester composition enhances the gas barrier properties of
the polyester composition at low loading levels, desirably in the
range of about 0.1 to about 10 weight percent of the polyester
composition, more desirably in the range of about 1 to about 6
weight percent of the polyester composition, and still more
desirably in the range of about 2 to about 4 weight percent of the
polyester composition. At low loading levels, a slight barrier
improvement factor (BIF) occurs. Although the improvement in the
BIF may be substantial at high loading levels, the physical
properties of the PET deteriorate and make forming a container more
difficult. The BIF is a measure of enhanced gas barrier properties
(the ratio of the gas transmission rate of a polyester composition
without an additive to the gas transmission rate of a polyester
composition with an additive). The BIF that can be observed by the
use of gas barrier enhancing additives provided herein can range
from about 1.05 to greater than 2, with typical values of BIF being
from about 1.15 to about 1.5.
[0039] According to an embodiment, the polyester composition
comprises a polyester present in the polyester composition in an
amount in the range of about 99.9 to about 90 weight percent of the
polyester composition and a gas barrier enhancing additive present
in the polyester composition in an amount in the range of about 0.1
to about 10 weight percent of the polyester composition.
[0040] In particular embodiments, the polyester compositions
provided herein may further comprise a suitable creep control
agent. Suitable creep control agents are known to those skilled in
the art for enhancing mechanical properties of polyesters; however,
Applicants have surprisingly discovered that the combination of
creep control agents with the gas barrier enhancing additives
provided herein further enhances the gas barrier properties of the
polyester composition. Such creep control agents are further
described below, and are described in detail in co-pending U.S.
patent application Ser. No. 12/629,657, the disclosure of which is
incorporated herein by reference in its entirety.
II. Gas Barrier Enhancing Additives
[0041] The gas barrier enhancing additives provided herein
generally comprise gas barrier additives having decreased
volatility as compared to previously discovered gas barrier
additives. As used herein, the terms "gas barrier enhancing
additive," "gas barrier enhancement additive," and "gas barrier
additive" are synonymous and may be used interchangeably.
[0042] In an embodiment, a gas barrier enhancing additive having
the chemical structure of Formula I or Formula II is provided:
##STR00003##
[0043] wherein X and X.sup.6, independent of one another, comprise
hydrogen, halide, heteroatom, hydroxyl, amino, amido, alkylamino,
arylamino, alkoxy, aryloxy, nitro, acyl, cyano, sulfo, sulfato,
mercapto, imino, sulfonyl, sulfenyl, sulfinyl, sulfamoyl,
phosphonyl, phosphinyl, phosphoryl, phosphino, thioester,
thioether, anhydride, oximno, hydrazino, carbamyl, phosphonic acid,
phosphonato, or a C.sub.1-C.sub.10 monovalent hydrocarbon which may
be unsubstituted or substituted with one or more functional
moieties;
[0044] wherein X.sup.1, X.sup.2, X.sup.3, X.sup.4, and X.sup.5,
independent of one another, comprise a heteroatom or a
C.sub.1-C.sub.10 divalent hydrocarbon, wherein each heteroatom or
C.sub.1-C.sub.10 divalent hydrocarbon may be unsubstituted or
substituted with one or more functional moieties or one or more
C.sub.1-C.sub.10 hydrocarbyls that may be unsubstituted or
substituted with one or more functional moieties; and
[0045] wherein s, t, u, and v, independent of one another, may be a
number from 0 to 10.
[0046] In particular embodiments, when X.sup.3 may comprise a
C.sub.6 or C.sub.10 divalent aromatic hydrocarbon, X and X.sup.6,
independent of one another, may comprise a hydrogen, halide,
heteroatom, hydroxyl, amino, amido, alkylamino, arylamino, alkoxy,
aryloxy, nitro, acyl, cyano, sulfo, sulfato, mercapto, imino,
sulfonyl, sulfenyl, sulfinyl, sulfamoyl, phosphonyl, phosphinyl,
phosphoryl, phosphino, thioester, thioether, anhydride, oximno,
hydrazino, carbamyl, phosphonic acid, phosphonato, or a
C.sub.3-C.sub.10 monovalent cyclic or heterocyclic non-aryl
hydrocarbon which may be unsubstituted or substituted with one or
more functional moieties.
[0047] In an embodiment of the compound of Formula I, wherein X and
X.sup.6 each comprise a phenyl group, the gas barrier additive
comprises a compound having the chemical structure:
##STR00004##
[0048] In an embodiment of the compound of Formula I, wherein X and
X.sup.6 each comprise a phenyl group and s and v are 0, the gas
barrier additive comprises a compound having the chemical
structure:
##STR00005##
[0049] In an embodiment of the compound of Formula I, wherein X and
X.sup.6 each comprise a phenyl group and s, t, u, and v are 0, the
gas barrier additive comprises a compound having the chemical
structure:
##STR00006##
[0050] In an embodiment of the compound of Formula I, wherein X and
X.sup.6 each comprise a phenyl group, s, t, u and v are 0, and
X.sup.3 comprises a divalent isosorbide, the gas barrier additive
comprises dibenzoyl isosorbide, a compound having the chemical
structure:
##STR00007##
[0051] In an embodiment of the compound of Formula I, wherein X and
X.sup.6 comprise a phenyl group, s, t, u, and v are 0, and X.sup.3
comprises a divalent cyclohexane, the gas barrier additive
comprises a compound having the chemical structure:
##STR00008##
[0052] In an embodiment of the compound of Formula I, wherein X and
X.sup.6 each comprise a phenyl group, s and v are 0, t and u are 1,
and X.sup.2 and X.sup.4 each comprise a divalent C.sub.1
hydrocarbon, the gas barrier additive comprises a compound having
the chemical structure:
##STR00009##
[0053] In an embodiment of the compound of Formula I, wherein X and
X.sup.6 each comprise a phenyl group, s and v are 0, t and u are 1,
X.sup.2 and X.sup.4 each comprise a divalent C.sub.1 hydrocarbon,
and X.sup.3 comprises a divalent hydro bi-furan, the gas barrier
additive comprises a compound having the chemical structure:
##STR00010##
[0054] In an embodiment of the compound of Formula I, wherein X and
X.sup.6 comprise a phenyl group, s and v are 0, t and u are 1,
X.sup.2 and X.sup.4 comprise a divalent C.sub.1 hydrocarbon, and
X.sup.3 comprises a divalent cyclohexane, the gas barrier additive
comprises a compound having the chemical structure:
##STR00011##
[0055] In an embodiment of the compound of Formula I, wherein X and
X.sup.6 each comprise a naphthyl group, the gas barrier additive
comprises a compound having the chemical structure:
##STR00012##
[0056] In an embodiment of the compound of Formula I, wherein X and
X.sup.6 each comprise a naphthyl group and s and v are 0, the gas
barrier additive comprises a compound having the chemical
structure:
##STR00013##
[0057] In an embodiment of the compound of Formula I, wherein X and
X.sup.6 each comprise a naphthyl group, s and v are 0, t and u are
1, and X.sup.2 and X.sup.4 each comprise a divalent C.sub.1
hydrocarbon, the gas barrier additive comprises a compound having
the chemical structure:
##STR00014##
[0058] In an embodiment of the compound of Formula I, wherein X and
X.sup.6 each comprise a naphthyl group, s and v are 0, t and u are
1, each X.sup.2 and X.sup.4 comprise a divalent C.sub.1
hydrocarbon, and X.sup.3 comprises a divalent cyclohexane which may
be ortho-, meta-, or para-substituted, the gas barrier additive
comprises a compound having the chemical structure:
##STR00015##
For example, in a particular embodiment wherein the divalent
cyclohexane is para-substituted, the gas barrier additive comprises
cyclohexane-1,4-diylbis(methylene)di-2-naphthoate, a compound
having the chemical structure:
##STR00016##
[0059] In an embodiment of the compound of Formula II, wherein X
and X.sup.6 each comprise a cyclohexyl group, the gas barrier
additive comprises a compound having the chemical structure:
##STR00017##
[0060] In an embodiment of the compound of Formula II, wherein X
and X.sup.6 each comprise a cyclohexyl group and s and v are 0, the
gas barrier additive comprises a compound having the chemical
structure:
##STR00018##
[0061] In an embodiment of the compound of Formula II, wherein X
and X.sup.6 each comprise a cyclohexyl group and s, t, u, and v are
0, the gas barrier additive comprises a compound having the
chemical structure:
##STR00019##
[0062] In an embodiment of the compound of Formula II, wherein X
and X.sup.6 each comprise a cyclohexyl group, s, t, u, and v are 0,
and X.sup.3 comprises a divalent benzene which may be ortho-,
meta-, or para-substituted, the gas barrier additive comprises a
compound having the chemical structure:
##STR00020##
For example, in a particular embodiment wherein the divalent
benzene is para-substituted, the gas barrier additive comprises
dicyclohexyl terephthalate, a compound having the chemical
structure:
##STR00021##
In another embodiment the divalent benzene may be meta-substituted
such that the gas barrier additive comprises dicyclohexyl
isophthalate, a compound having the chemical structure:
##STR00022##
[0063] In an embodiment of the compound of Formula II, wherein X
and X.sup.6 each comprise a cyclohexyl group, s, t, u, and v are 0,
and X.sup.3 comprises a divalent naphthalene which may be
substituted at any position on either ring (e.g., 1, 2, 3, 4, 5, 6,
7, or 8), the gas barrier additive comprises a compound having the
chemical structure:
##STR00023##
For example, in a particular embodiment wherein the divalent
naphthalene is substituted at the 2 and 6 positions, the gas
barrier additive comprises dicyclohexyl
naphthalene-2,6-dicarboxylate, a compound having the chemical
structure:
##STR00024##
[0064] In an embodiment of the compound of Formula II, wherein X
and X.sup.6 each comprise a benzoate group, the gas barrier
additive comprises a compound having the chemical structure:
##STR00025##
[0065] In an embodiment of the compound of Formula II, wherein X
and X.sup.6 each comprise a benzoate group and t and u are 0, the
gas barrier additive comprises a compound having the chemical
structure:
##STR00026##
[0066] In an embodiment of the compound of Formula II, wherein X
and X.sup.6 each comprise a benzoate group, t and u are 0, s and v
are 1, and X.sup.1 and X.sup.5 each comprise a divalent C.sub.1
hydrocarbon, the gas barrier additive comprises a compound having
the chemical structure:
##STR00027##
[0067] In an embodiment of the compound of Formula II, wherein X
and X.sup.6 each comprise a benzoate group, t and u are 0, s and v
are 1, and X.sup.1 and X.sup.5 each comprise a divalent C.sub.1
hydrocarbon, and X.sup.3 is a divalent benzene which may be ortho-,
meta-, or para-substituted, the gas barrier additive comprises a
compound having the chemical structure:
##STR00028##
In a particular embodiment wherein the divalent benzene is
para-substituted, the gas barrier additive comprises
bis(2-(benzoyloxy)ethyl)terephthalate), a compound having the
chemical structure:
##STR00029##
[0068] In an embodiment of the compound of Formula II, wherein X
and X.sup.6 each comprise a benzoate group, the gas barrier
additive comprises a compound having the chemical structure:
##STR00030##
[0069] In an embodiment of the compound of Formula II, wherein X
and X.sup.6 each comprise a benzoate group, s and v are 2, and
X.sup.1 and X.sup.5 each comprise a divalent C.sub.1 hydrocarbon,
the gas barrier additive comprises a compound having the chemical
structure:
##STR00031##
[0070] In an embodiment of the compound of Formula II, wherein X
and X.sup.6 each comprise a benzoate group, s and v are 2, X.sup.1
and X.sup.5 each comprise a divalent C.sub.1 hydrocarbon, t and u
are 1, and X.sup.2 and X.sup.4 each comprise a divalent benzoate
which may be ortho-, meta-, or para-substituted, the gas barrier
additive comprises a compound having the chemical structure:
##STR00032##
[0071] In an embodiment of the compound of Formula II, wherein X
and X.sup.6 each comprise a benzoate group, s and v are 2, X.sup.1
and X.sup.5 each comprise a divalent C.sub.1 hydrocarbon, t and u
are 1, X.sup.2 and X.sup.4 each comprise a divalent benzoate which
may be ortho-, meta-, or para-substituted, and X.sup.3 comprises a
divalent C.sub.2 hydrocarbon, the gas barrier additive comprises a
compound having the chemical structure:
##STR00033##
In a particular embodiment wherein the divalent benzoates are
meta-substituted, the gas barrier additive comprises
bis(2-(benzoyloxy)ethyl)'-ethane-1,2-diyl diisophthalate, a
compound having the chemical structure:
##STR00034##
[0072] In an embodiment of the compound of Formula II, wherein X
and X.sup.6 each comprise an aryloxy group (e.g., a phenoxy group),
the gas barrier additive comprises a compound having the chemical
structure:
##STR00035##
[0073] In an embodiment of the compound of Formula II, wherein X
and X.sup.6 each comprise an aryloxy group (e.g., a phenoxy group),
t and u are 0, the gas barrier additive comprises a compound having
the chemical structure:
##STR00036##
[0074] In an embodiment of the compound of Formula II, wherein X
and X.sup.6 each comprise an aryloxy group (e.g., a phenoxy group),
t and u are 0, and X.sup.3 comprises a divalent benzene which may
be ortho-, meta-, or para-substituted, the gas barrier additive
comprises a compound having the chemical structure:
##STR00037##
[0075] In an embodiment of the compound of Formula II, wherein X
and X.sup.6 each comprise an aryloxy group (e.g., a phenoxy group),
t and u are 0, s and v are 1, X.sup.1 and X.sup.5 comprise a
straight-chain divalent C.sub.2 hydrocarbon, and X.sup.3 comprises
a divalent benzene which may be ortho-, meta-, or para-substituted,
the gas barrier additive comprises a compound having the chemical
structure:
##STR00038##
For example, in a particular embodiment wherein the divalent
benzene is para-substituted, the gas barrier additive comprises
bis(2-phenoxyethyl)terephthalate (PEM), a compound having the
chemical structure:
##STR00039##
[0076] As used herein, the term "heteroatom" refers to any atom
other than carbon or hydrogen. Typically, the heteroatom comprises
nitrogen, oxygen, or sulfur.
[0077] The term "hydrocarbyl," as used herein, is used to describe
a monovalent hydrocarbon that may form one bond with another atom
within a single chemical compound. The term "divalent hydrocarbon,"
as used herein, is used to describe a hydrocarbon which may form
two bonds to either one other atom as a double bond or two other
atoms as separate single bonds, all within a single chemical
compound. The term "triavalent hydrocarbon," as used herein, is
used to describe a hydrocarbon which may form three bonds to either
one atom as a triple bond, two other atoms as a double and single
bond, or three atoms as separate single bonds, all within a single
chemical compound. A "tetravalent carbon atom," as used herein, is
used to describe a carbon atom that may form four bonds to either
two other atoms as one triple bond and one single bond, two other
atoms as two double bonds, three different atoms as one double bond
and two single bonds, or four different atoms as four separate
single bonds, all within a single chemical compound.
[0078] The terms "hydrocarbon" and "hydrocarbyl," as used herein,
include an aliphatic group, an aromatic or aryl group, a cyclic
group, a heterocyclic group, or any combination thereof and any
substituted derivative thereof, including but not limited to, a
halide, an alkoxide, or an amide-substituted derivative thereof.
Also included in the definition of the hydrocarbyl are any
unsubstituted, branched, or linear analogs thereof. The hydrocaryl
may be substituted with one or more functional moieties as
described hereinbelow.
[0079] Examples of aliphatic groups, in each instance, include, but
are not limited to, an alkyl group, a cycloalkyl group, an alkenyl
group, a cycloalkenyl group, an alkynyl group, an alkadienyl group,
a cyclic group, and the like, and includes all substituted,
unsubstituted, branched, and linear analogs or derivatives thereof.
Examples of alkyl groups include, but are not limited to, methyl,
ethyl, propyl, isopropyl, n-butyl, t-butyl, isobutyl, pentyl,
hexyl, isohexyl, heptyl, 4,4-dimethylpentyl, octyl,
2,2,4-trimethylpentyl, nonyl, and decyl. Cycloalkyl moieties may be
monocyclic or multicyclic, and examples include cyclopropyl,
cyclobutyl, cyclopentyl, cyclohexyl, and adamantyl. Additional
examples of alkyl moieties have linear, branched and/or cyclic
portions (e.g., 1-ethyl-4-methyl-cyclohexyl). Representative
alkenyl moieties include vinyl, allyl, 1-butenyl, 2-butenyl,
isobutylenyl, 1-pentenyl, 2-pentenyl, 3-methyl-1-butenyl,
2-methyl-2-butenyl, 2,3-dimethyl-2-butenyl, 1-hexenyl, 2-hexenyl,
3-hexenyl, 1-heptenyl, 2-heptenyl, 3-heptenyl, 1-octenyl,
2-octenyl, 3-octenyl, 1-nonenyl, 2-nonenyl, 3-nonenyl, 1-decenyl,
2-decenyl and 3-decenyl. Representative alkynyl moieties include
acetylenyl, propynyl, 1-butynyl, 2-butynyl, 1-pentynyl, 2-pentynyl,
3-methyl-1-butynyl, 4-pentynyl, 1-hexynyl, 2-hexynyl, 5-hexynyl,
1-heptynyl, 2-heptynyl, 6-heptynyl, 1-octynyl, 2-octynyl,
7-octynyl, 1-nonynyl, 2-nonynyl, 8-nonynyl, 1-decynyl, 2-decynyl
and 9-decynyl.
[0080] Examples of aryl or aromatic moieties include, but are not
limited to, anthracenyl, azulenyl, biphenyl, fluorenyl, indan,
indenyl, naphthyl, phenyl, 1,2,3,4-tetrahydro-naphthalene, and the
like, including substituted derivatives thereof, in each instance
having from 6 to about 10 carbons. Substituted derivatives of
aromatic compounds include, but are not limited to, tolyl, xylyl,
mesityl, and the like, including any heteroatom substituted
derivative thereof. Examples of cyclic groups, in each instance,
include, but are not limited to, cycloparaffins, cycloolefins,
cycloacetylenes, arenes such as phenyl, bicyclic groups and the
like, including substituted derivatives thereof. Thus
heteroatom-substituted cyclic groups and bicyclic groups such as
furanyl and isosorbyl are also included herein.
[0081] In each instance, aliphatic and cyclic groups are groups
comprising an aliphatic portion and a cyclic portion, examples of
which include, but are not limited to, groups such as:
--(CH.sub.2).sub.mC.sub.6H.sub.qM.sub.5-q wherein m is an integer
from 1 to about 10, q is an integer from 1 to 5, inclusive;
(CH.sub.2).sub.mC.sub.6H.sub.qR.sub.10-q wherein m is an integer
from 1 to about 10, q is an integer from 1 to 10, inclusive; and
(CH.sub.2).sub.mC.sub.5H.sub.qR.sub.9-q wherein m is an integer
from 1 to about 10, q is an integer from 1 to 9, inclusive. In each
instance and as defined above, M is independently selected from: an
aliphatic group; an aromatic group; a cyclic group; any combination
thereof; any substituted derivative thereof, including but not
limited to, a halide-, an alkoxide-, or an amide-substituted
derivative thereof any one of which has from 1 to about 10 carbon
atoms; or hydrogen. In one aspect, aliphatic and cyclic groups
include, but are not limited to: --CH.sub.2C.sub.6H.sub.5;
--CH.sub.2C.sub.6H.sub.4F; --CH.sub.2C.sub.6H.sub.4Cl;
--CH.sub.2C.sub.6H.sub.4Br; --CH.sub.2C.sub.6H.sub.4I;
--CH.sub.2C.sub.6H.sub.4OMe; --CH.sub.2C.sub.6H.sub.4OEt;
--CH.sub.2C.sub.6H.sub.4NH.sub.2;
--CH.sub.2C.sub.6H.sub.4NMe.sub.2;
--CH.sub.2C.sub.6H.sub.4NEt.sub.2;
--CH.sub.2CH.sub.2C.sub.6H.sub.5;
--CH.sub.2CH.sub.2C.sub.6H.sub.4F;
--CH.sub.2CH.sub.2C.sub.6H.sub.4Cl;
--CH.sub.2CH.sub.2C.sub.6H.sub.4Br;
--CH.sub.2CH.sub.2C.sub.6H.sub.4I;
--CH.sub.2CH.sub.2C.sub.6H.sub.4OMe;
--CH.sub.2CH.sub.2C.sub.6H.sub.4OEt;
--CH.sub.2CH.sub.2C.sub.6H.sub.4NH.sub.2;
--CH.sub.2CH.sub.2C.sub.6H.sub.4NMe.sub.2;
--CH.sub.2CH.sub.2C.sub.6H.sub.4NEt.sub.2; any regioisomer thereof,
or any substituted derivative thereof.
[0082] In each instance, the heterocycle comprising at least one
N-, O-, or S-heteroatom may be selected from the group consisting
of: morpholinyl, thiomorpholinyl, thiomorpholinyl S-oxide,
thiomorpholinyl S,S-dioxide, piperazinyl, homopiperazinyl,
pyrrolidinyl, pyrrolinyl, tetrahydropyranyl, piperidinyl,
tetrahydrofuranyl, tetrahydrothienyl, homopiperidinyl,
homomorpholinyl, homothiomorpholinyl, homothiomorpholinyl
S,S-dioxide, oxazolidinonyl, dihydropyrazolyl, dihydropyrrolyl,
dihydropyrazinyl, dihydropyridinyl, dihydropyrimidinyl,
dihydrofuryl, dihydropyranyl, tetrahydrothienyl S-oxide,
tetrahydrothienyl S,S-dioxide, and homothiomorpholinyl S-oxide,
pyridinyl, pyrimidinyl, quinolinyl, benzothienyl, indolyl,
indolinyl, pryidazinyl, pyrazinyl, isoindolyl, isoquinolyl,
quinazolinyl, quinoxalinyl, phthalazinyl, imidazolyl, isoxazolyl,
pyrazolyl, oxazolyl, thiazolyl, indolizinyl, indazolyl,
benzothiazolyl, benzimidazolyl, benzofuranyl, furanyl, thienyl,
pyrrolyl, oxadiazolyl, thiadiazolyl, triazolyl, tetrazolyl,
oxazolopyridinyl, imidazopyridinyl, isothiazolyl, naphthyridinyl,
cinnolinyl, carbazolyl, beta-carbolinyl, isochromanyl, chromanyl,
tetrahydroisoquinolinyl, isoindolinyl, isobenzotetrahydrofuranyl,
isobenzotetrahydrothienyl, isobenzothienyl, isosorbyl,
benzoxazolyl, pyridopyridinyl, benzotetrahydrofuranyl,
benzotetrahydrothienyl, purinyl, benzodioxolyl, triazinyl,
phenoxazinyl, phenothiazinyl, pteridinyl, benzothiazolyl,
imidazopyridinyl, imidazothiazolyl, dihydrobenzisoxazinyl,
benzisoxazinyl, benzoxazinyl, dihydrobenzisothiazinyl,
benzopyranyl, benzothiopyranyl, coumarinyl, isocoumarinyl,
chromonyl, chromanonyl, pyridinyl-N-oxide, tetrahydroquinolinyl,
dihydroquinolinyl, dihydroquinolinonyl, dihydroisoquinolinonyl,
dihydrocoumarinyl, dihydroisocoumarinyl, isoindolinonyl,
benzodioxanyl, benzoxazolinonyl, pyrrolyl N-oxide, pyrimidinyl
N-oxide, pyridazinyl N-oxide, pyrazinyl N-oxide, quinolinyl
N-oxide, indolyl N-oxide, indolinyl N-oxide, isoquinolyl N-oxide,
quinazolinyl N-oxide, quinoxalinyl N-oxide, phthalazinyl N-oxide,
imidazolyl N-oxide, isoxazolyl N-oxide, oxazolyl N-oxide, thiazolyl
N-oxide, indolizinyl N-oxide, indazolyl N-oxide, benzothiazolyl
N-oxide, benzimidazolyl N-oxide, pyrrolyl N-oxide, oxadiazolyl
N-oxide, thiadiazolyl N-oxide, triazolyl N-oxide, tetrazolyl
N-oxide, benzothiopyranyl S-oxide, or benzothiopyranyl
S,S-dioxide.
[0083] The term alkoxy, as used herein, and unless otherwise
specified, refers to a moiety of the structure --O-alkyl, wherein
alkyl is as defined above.
[0084] The term acyl, as used herein, refers to a group of the
formula C(O)R', wherein R' is an alkyl, aryl, heteroaryl,
heterocyclic, alkaryl or aralkyl group, or substituted alkyl, aryl,
heteroaryl, heterocyclic, aralkyl or alkaryl, wherein these groups
are as defined above.
[0085] Unless otherwise indicated, the term "substituted," when
used to describe a chemical structure or moiety, refers to a
derivative of that structure or moiety wherein one or more of its
hydrogen atoms is substituted with a chemical moiety or functional
group. Non-limiting examples of suitable functional moieties, as
used herein, include halide, hydroxyl, amino, amido, alkylamino,
arylamino, alkoxy, aryloxy, nitro, acyl, cyano, sulfo, sulfato,
mercapto, imino, sulfonyl, sulfenyl, sulfinyl, sulfamoyl,
phosphonyl, phosphinyl, phosphoryl, phosphino, thioester,
thioether, anhydride, oximno, hydrazino, carbamyl, phosphonic acid,
phosphonato, ether, ketone, ester, and any other viable functional
group.
III. Creep Control Agents
[0086] In one aspect of this disclosure, the polyester composition
comprises a creep control agent having the chemical structure of
Formula I:
##STR00040##
[0087] wherein R.sup.1, R.sup.2, R.sup.3, and R.sup.4, independent
of one another, may comprise a heteroatom, a tetravalent carbon
atom, or a C.sub.1-C.sub.3 divalent or trivalent hydrocarbon;
wherein each heteroatom, tetravalent carbon atom, or
C.sub.1-C.sub.3 divalent or trivalent hydrocarbon may be
unsubstituted or substituted with one or more functional moieties
or one or more C.sub.1-C.sub.10 hydrocarbyls that may be
unsubstituted or substituted with one or more functional
moieties;
[0088] wherein i, ii, iii, iv, v, and vi, independent of one
another, comprise a single, double, or triple bond; wherein when i
is a double bond, ii and vi are single bonds; wherein when ii is a
double bond, i and iii are single bonds; wherein when iii is a
double bond, ii and iv are single bonds; wherein when iv is a
double bond iii and v are single bonds; wherein when v is a double
bond, iv and vi are single bonds; wherein when vi is a double bond,
i and v are single bonds; wherein vii may be a single bond, double
bond, or no bond at all connects R.sup.3 and R.sup.4;
[0089] wherein m, n, o, and p, independent of one another, may be 0
or 1; wherein when m is 0, bonds ii and iii form a single
continuous bond; wherein when n is 0, bonds vi and v form a single
continuous bond; wherein when o is O, R.sup.4 is bonded to R.sup.1
by a single bond; and wherein when p is O, R.sup.3 is bonded to
R.sup.2 by a single bond.
[0090] In a particular embodiment of the compound of Formula I,
wherein m, n, o, and p are 0; and i, ii/iii, iv, and v/vi are
single bonds; the creep control agent comprises
cyclobutane-1,2,3,4-tetracarboxylic acid dianhydride, a compound
having the chemical structure:
##STR00041##
[0091] In another embodiment of the compound of Formula I, wherein
n, o, and p are 0; m is 1; i, ii, iii, iv, and v/vi are single
bonds; and R.sup.1 is oxygen; the creep control agent comprises
2,3,4,5-tetrahydro-2,3,4,5-tetracarboxylic-furan dianhydride, a
compound having the chemical structure:
##STR00042##
[0092] In yet another embodiment of the compound of Formula I,
wherein m and n are 1; o and p are 0; R.sup.1 and R.sup.2 are
trivalent hydrocarbons comprising 1 carbon atom; i, iii, and v are
double bonds; and ii, iv, and vi are single bonds; the creep
control agent comprises pyromellitic dianhydride, a compound having
the chemical structure:
##STR00043##
[0093] In yet another embodiment of the compound of Formula I,
wherein m, n, o, and p are 1; R.sup.1, R.sup.2, R.sup.3, and
R.sup.4 are trivalent hydrocarbons comprising 1 carbon atom; i, ii,
iii, iv, v, and vi are single bonds; and vii is a double bond; the
creep control agent comprises
bicyclo[2.2.2]oct-3,4-ene-1,2,5,6-tetracarboxylic acid dianhydride,
a compound having the chemical structure:
##STR00044##
[0094] In another aspect of this disclosure, the polyester
composition comprises a creep control agent having the chemical
structure of Formula II:
##STR00045##
[0095] wherein A, A', A'', E, D, G, G', G'', L, and J, independent
of one another, may comprise a heteroatom, a tetravalent carbon
atom, or a C.sub.1-C.sub.3 divalent or trivalent hydrocarbon;
wherein each heteroatom, tetravalent carbon atom, or
C.sub.1-C.sub.3 divalent or trivalent hydrocarbon may be
unsubstituted or substituted with one or more functional moieties
or one or more C.sub.1-C.sub.10 hydrocarbyls that may be
unsubstituted or substituted with one or more functional
moieties;
[0096] wherein i, ii, iii, iv, v, vi, vii, viii, ix, and x,
independent of one another, may comprise a single or double bond;
wherein when i is a double bond, ii and v are single bonds; wherein
when ii is a double bond, i and iii are single bonds; wherein when
iii is a double bond, ii and iv are single bonds; wherein when iv
is a double bond, iii and v are single bonds; wherein when v is a
double bond, i and iv are single bonds; wherein when vi is a double
bond, vii and x are single bonds; wherein when vii is a double
bond, vi and viii are single bonds; wherein when viii is a double
bond, vii and ix are single bonds; wherein when ix is a double
bond, viii and x are single bonds; wherein when x is a double bond,
vi and ix are single bonds;
[0097] wherein b, c, d, e, f, g, h, i, j, and k, independent of one
another may be 0 or 1;
[0098] wherein a may be 0 or 1; and
[0099] wherein R.sup.5 may be a heteroatom or a C.sub.1-C.sub.10
divalent hydrocarbon that may be unsubstituted or substituted with
one or more functional moieties, one or more heteroatoms, or one or
more C.sub.1-C.sub.10 hydrocarbyls that may be unsubstituted or
substituted with one or more functional moieties.
[0100] In one embodiment of the compound of Formula II, wherein b,
c, d, e, f, g, h, i, j, and k, are 1; a is 0; E and L are divalent
hydrocarbons comprising 1 carbon atom; A', D, J, G' are trivalent
hydrocarbons comprising 1 carbon atom; A and G'' are oxygen; A''
and G are nitrogen; i, ii, iv, v, vi, viii, ix, and x are single
bonds; iii and vii are double bonds; and the ring comprising A, A',
A'', D, and E is bonded to the ring comprising G, G', G'', L, and J
via a single bond between D and J, the creep control agent is
4,'-bisoxazoline, a compound having the chemical structure:
##STR00046##
[0101] In another embodiment of the compound of Formula II, wherein
b, c, d, e, f, g, h, i, j, and k are 1; a is 0; A', D, J, G' are
trivalent hydrocarbons comprising 1 carbon atom; E and L are
divalent hydrocarbons comprising 1 carbon atom; A and G are
nitrogen; A'' and G'' are oxygen; ii and vii are double bonds; i,
iii, iv, v, vi, viii, ix, and x are single bonds; and the ring
comprising A, A', A'', D, and E is bonded to the ring comprising G,
G', G'', L, and J via a single bond between D and J, the creep
control agent is 4,4'-bisoxazoline, a compound having the chemical
structure:
##STR00047##
[0102] In yet another embodiment of the compound of Formula II,
wherein b, c, d, e, f, g, h, i, j, and k are 1; a is 0; A'' and G''
are oxygen; E and L are nitrogen; J and D are tetravalent carbon
atoms; A, A', G and G' are divalent hydrocarbons comprising 1
carbon atom; v and x are double bonds; i, ii, iii, iv, vi, vii,
viii, and ix are single bonds; and the ring comprising A, A', A'',
D, and E is bonded to the ring comprising G, G', G'', L, and J, via
a single bond between D and J, the creep control agent is
2,2'-bis(2-oxazoline), a compound having the chemical
structure:
##STR00048##
[0103] In yet another embodiment of the compound of Formula II,
wherein a, b, c, d, e, f, g, h, i, j, and k are 1; A', D, J, G' are
trivalent hydrocarbons comprising 1 carbon atom; R.sup.5, E and L
are divalent hydrocarbons comprising 1 carbon atom; A and G are
nitrogen; A'' and G'' are oxygen; ii and vii are double bonds; i,
iii, iv, v, vi, viii, ix, and x are single bonds; and R.sup.5 is
bonded to D and J, the creep control agent is
bis(4,5-dihydrooxazol-5-yl)methane, a compound having the chemical
structure:
##STR00049##
[0104] In yet another embodiment of the compound of Formula II,
wherein d, e, f, g, k, j, and a are 1; b, c, h, and i are 0; E and
L are oxygen; R.sup.5, A'', and G'' are divalent hydrocarbons
comprising 1 carbon atom; D, and J are trivalent hydrocarbons
comprising carbon atom; iv, v, ix, and x are single bonds; E and
A'' are bonded directly together via a single bond; L and G'' are
bonded together via a single bond; and R.sup.5 is bonded to D and
J, the creep control agent is bis(4,5-dihydrooxaol-5-yl)methane, a
compound having the chemical structure:
##STR00050##
[0105] In another aspect of this disclosure, the polyester
composition comprises a creep control agent having the chemical
structure of Formula III:
##STR00051##
[0106] wherein R.sup.6 and R.sup.7, independent of one another, may
comprise a C.sub.1-C.sub.5 divalent hydrocarbon that may be
unsubstituted or substituted with one or more functional moieties,
one or more heteroatoms, or one or more C.sub.1-C.sub.10
hydrocarbyls that may be unsubstituted or substituted with one or
more functional moieties.
[0107] In one particular embodiment of the compound of Formula III,
wherein R.sup.6 and R.sup.7 are divalent hydrocarbons comprising 5
carbon atoms, the creep control agent is bis-carpolactam carbonyl,
a compound having the chemical structure:
##STR00052##
[0108] In yet another aspect of this disclosure, the polyester
composition comprises a creep control agent having the chemical
structure of Formula IV:
##STR00053##
[0109] wherein A.sup.1, A.sup.2, R.sup.8, R.sup.9, and R.sup.10,
independent of one another, may comprise a heteroatom, a
tetravalent carbon atom, a C.sub.1-C.sub.10 divalent or trivalent
hydrocarbon, or a C.sub.1-C.sub.10 hydrocarbyl that may be
unsubstituted or substituted with one or more functional
moieties;
[0110] wherein each heteroatom, tetravalent carbon atom, or
C.sub.1-C.sub.10 divalent or trivalent hydrocarbon may be
unsubstituted or substituted with one or more functional moieties
or one or more C.sub.1-C.sub.10 hydrocarbyls that may be
unsubstituted or substituted with one or more functional
moieties;
[0111] wherein m', n', and p', independent of one another, may be 0
or 1;
[0112] wherein i, ii, and iii, independent of one another may be a
single bond or a double bond;
[0113] wherein t, u, v, and w, independent of one another may be a
single bond, double bond, or triple bond; and
[0114] wherein q, r, and s may be from 0 to 10,000.
[0115] In one particular embodiment of the compound of Formula IV,
wherein q, r, p', m' are 0; s and n' are 1; R.sup.8 is
isobenzofuran-1,3-dione; i, ii, and iii are double bonds; the creep
control agent is biphenyl-2,3,2',3'-tetracarboxylic acid
dianhydride, a compound with the chemical structure:
##STR00054##
[0116] In another particular embodiment of the compound of Formula
IV, wherein q, and r are 0; s, p', n', and m' are 1; R.sup.8
comprises a tetravalent carbon atom; R.sup.9 comprises oxygen;
R.sup.10 comprises isobenzofuran-1,3-dione; u, i, ii, and iii are
double bonds; and v is a single bond, the creep control agent is
benzophenone-3,4,3',4'-tetracarboxylic acid dianhydride, a compound
with the chemical formula:
##STR00055##
[0117] In another particular embodiment of the compound of Formula
IV, wherein q and s are 1000; r and p' are 0; m' and n' are 1;
R.sup.8 is a trivalent hydrocarbon comprising 1 carbon atom;
R.sup.10 is a divalent hydrocarbon comprising 1 carbon atom; t and
v are single bonds; i, ii, and iii are double bonds; and A.sup.1 is
a methyl methacrylate monomer, the creep control agent is a
co-polymer of 5-vinylisobenzofuran-1,3-dione and methyl
methacrylate (MMA), a co-polymer with the chemical formula:
##STR00056##
[0118] In another particular embodiment of the compound of Formula
IV, wherein q and s are 1000; r and p' are 0; m' and n' are 1;
R.sup.8 is a trivalent hydrocarbon comprising 1 carbon atom;
R.sup.10 is a divalent hydrocarbon comprising one carbon atom; t
and v are single bonds; i, ii, and iii are double bonds; and
A.sup.1 is a styrene monomer, the creep control agent is a
co-polymer of 5-vinylisobenzofuran-1,3-dione and styrene, a
co-polymer with the chemical formula:
##STR00057##
[0119] In yet another particular embodiment of the compound of
Formula IV, wherein r, q, and s are 1000; p' is 0; m' and n' are 1;
R.sup.8 is a trivalent hydrocarbon comprising 1 carbon atom;
R.sup.10 is a divalent hydrocarbon comprising one carbon atom; w,
t, and v are single bonds; i, ii, and iii are double bonds; A.sup.1
is a methyl methacrylate monomer; and A.sup.2 is a styrene monomer,
the creep control agent is a co-polymer of methyl methacrylate,
5-vinylisobenzofuran-1,3-dione, and styrene, a co-polymer with the
chemical formula:
##STR00058##
[0120] In another aspect of this disclosure, the polyester
composition comprises a creep control agent having the chemical
structure of Formula V:
##STR00059##
[0121] wherein R may comprise a heteroatom or a C.sub.1-C.sub.10
hydrocarbyl which may be unsubstituted or substituted with one or
more functional moieties; and
[0122] wherein m'', n'', and o'', independent of one another, may
be from 0 to 1,000.
[0123] Formula V represents the chemical structure of
Joncryl.RTM.-ADR, which is sold by BASF Corporation, Florham Park,
N.J., 07932. The molecular weight of the polymer represented by
Formula V is below about 3000.
[0124] In a particular embodiment of the compound of Formula V,
wherein m'', n'', and o'' are 100; and R is a methyl, the creep
control agent is a co-polymer having the chemical structure:
##STR00060##
[0125] In yet another aspect of this disclosure, the polyester
composition comprises a creep control agent having the chemical
structure of Formula VI:
##STR00061##
[0126] wherein R.sup.11, R.sup.12, R.sup.13, and R.sup.14,
independent of one another, may comprise a heteroatom, a
tetravalent carbon atom, or a C.sub.1-C.sub.3 divalent or trivalent
hydrocarbon; wherein each heteroatom, tetravalent carbon atom, or
C.sub.1-C.sub.3 divalent or trivalent hydrocarbon may be
unsubstituted or substituted with one or more functional moieties
or one or more C.sub.1-C.sub.10 hydrocarbyls that may be
unsubstituted or substituted with one or more functional moieties;
and
[0127] wherein i, ii, iii, iv, v, vi, vii, viii, ix, x, and xi,
independent of one another, are a single bond or double bond;
wherein when i is a double bond, ii and vi are single bonds;
wherein when ii is a double bond, i, iii, and vii are single bonds;
wherein when iii is a double bond, ii, iv, vii, and xi are single
bonds; wherein when iv is a double bond, iii, v, and xi are single
bonds; wherein when v is a double bond, vi and iv are single bonds;
wherein when vi is a double bond, i and v are single bonds; wherein
when vii is a double bond, ii, iii, and viii are single bonds;
wherein when viii is a double bond, vi and ix are single bonds;
wherein when ix is a double bond, viii and x are single bonds;
wherein when x is a double bond, ix and xi are single bonds;
wherein when xi is a double bond, iv, x, and iii are single
bonds.
[0128] In a particular embodiment of the compound of Formula VI,
wherein R.sup.11, R.sup.12, R.sup.13, and R.sup.14 are trivalent
hydrocarbons comprising one carbon atom; vi, ii, iv, viii, and x
are double bonds; and i, iii, v, vii, ix are single bonds, the
creep control agent is 1,4,5,8-tetracarboxylic acid-naphthalene
dianhydride, a compound having the chemical formula:
##STR00062##
[0129] In yet another aspect of this disclosure, the polyester
composition comprises a creep control agent having the chemical
structure of Formula VII:
##STR00063##
[0130] wherein R.sup.15, R.sup.16, R.sup.17, R.sup.18, R.sup.19,
R.sup.20, R.sup.21, and R.sup.22, independent of one another, may
comprise a heteroatom, a tetravalent carbon atom, or a
C.sub.1-C.sub.3 divalent or trivalent hydrocarbon; wherein each
heteroatom, tetravalent carbon atom, or C.sub.1-C.sub.3 divalent or
trivalent hydrocarbon may be unsubstituted or substituted with one
or more functional moieties or one or more C.sub.1-C.sub.10
hydrocarbyls that may be unsubstituted or substituted with one or
more functional moieties; and
[0131] wherein i, ii, iii, iv, v, vi, vii, viii, ix, x, xi, xii,
xiii, xiv, xv, xvi, xvii, xviii, xix, xx, xxi, xxii, independent of
one another, are a double bond or single bond; wherein when i is a
double bond, ii and vi are single bonds; wherein when ii is a
double bond, i, iii, and vii are single bonds; wherein when iii is
a double bond, ii, iv, vii, and xi are single bonds; wherein when
iv is a double bond, iii, v, xi, and xii are single bonds; wherein
when v is a double bond, vi, iv, and xii are single bonds; wherein
when vi is a double bond, i and v are single bonds; wherein when
vii is a double bond, ii, iii and viii are single bonds; wherein
when viii is a double bond, vii and ix are single bonds; wherein
when ix is a double bond, viii and x are single bonds; wherein when
x is a double bond, ix, xi, and xiii are single bonds; wherein when
xi is a double bond, iii, iv, xiii and x are single bonds; wherein
when xii is a double bond, v, iv, xvi, and xiv are single bonds;
wherein when xiv is a double bond, xii, xvi, xv, and xix are single
bonds; wherein when xv is a double bond, xiii, xvii, xiv, and xix
are single bonds; when xiii is a double bond, xi, x, xv, and xvii
are single bonds; when xvi is a double bond, xii, xiv, and xviii
are single bonds; wherein when xviii is a double bond, xvi and xxi
are single bonds; wherein when xxi is a double bond, xviii and xxii
are single bonds; wherein when xxii is a double bond, xxi, xix, and
xxiii are single bonds; wherein when xix is a double bond, xiv, xv,
xxii, and xxiii are single bonds; wherein when xxiii is a double
bond, xix, xxii, and xxiv are single bonds; wherein when xxiv is a
double bond, xxiii and xx are single bonds; wherein when xx is a
double bond, xvii and xxiv are single bonds; and wherein when xvii
is a double bond, xv, xiii and xx are single bonds.
[0132] In a particular embodiment of the compound of Formula VI,
wherein R.sup.15, R.sup.16, R.sup.17, R.sup.18, R.sup.19, R.sup.20,
R.sup.21, and R.sup.22 are trivalent hydrocarbons comprising 1
carbon atom; ii, iv, vi, viii, x, xiv, xvii, xviii, xxii, and xxiv
are double bonds, and i, iii, v, vii, xi, xii, xiii, ix, xv, xvi,
xix, xxi, xxiii, and xx are single bonds; the creep control agent
is perylene-3,4,9,10-tetracarboxylic acid dianhydride, a compound
having the chemical structure:
##STR00064##
IV. Methods of Making Polyester Composition and Containers
[0133] As described above, the polyester compositions provided
herein are useful for making containers in which enhanced gas
barrier properties are desirable. In short, such containers are
made by forming the above described polyester compositions into the
desired container by conventional methods such as melt forming.
Suitable melt forming processes include, but are not limited to,
injection molding, extrusion, thermal forming and compression
molding of preforms followed by the blow molding of the melt formed
preforms into bottles. The particularly preferred method for making
the containers of this invention is stretch blow molding.
[0134] Methods for incorporating the gas barrier enhancing additive
into the container and polyester composition also are provided
herein. Such methods also are well known to those skilled in the
art. For example, an additive can be fed directly into the
polyester during the injection molding process, preblended with the
polyester resin prior to injection molding, or incorporated at high
concentrations with PET as masterbatch and then blended with the
polyester resin prior to both injection molding of the preform and
stretch blow molding of the container. Those skilled in the art
will appreciate that such methods may be modified depending on the
form of the additive being used. For example, when using additives
in powder form, the polyester resin may be ground to reduce the
size of the pellets and facilitate the formation of a homogeneous
blend.
[0135] FIG. 1 illustrates a system 10 in accordance with an
embodiment of this invention for making a rigid container preform
12 (illustrated in FIG. 2) and a rigid container 14 (illustrated in
FIG. 3) from the preform. As is shown in FIG. 1, PET 20 and a gas
barrier enhancing additive 22 are added to a feeder or hopper 24
that delivers the components to a hot melt extruder 26 in which the
components are melted and blended with a polyester. The hot melt
extruder 26 then extrudes the molten mixture of the polyester 20
and gas barrier enhancing additive 22 into an injection molding
device 28 to form the preform 12. The preform 12 is cooled and
removed from the injection molding device 28 and delivered to a
stretch blow molding device 30 which stretch blow molds the preform
12 into a finished rigid container 14.
[0136] The melt residence time of the preform production is
preferably less than five minutes and more preferably from about
one to about three minutes. The melt temperatures are desirably
from about 260 to about 300.degree. C. and more desirably from
about 270 to about 290.degree. C. The melt residence time begins
when the PET 20 and gas barrier enhancing additive 22 enter the
melt extruder 26 and start melting, and ends after injection of the
molten blend into the injection mold to form the preform 12
V. Containers
[0137] As is well known to those skilled in the art, containers can
be made by blow molding a container preform. Examples of suitable
preform and container structures are disclosed in U.S. Pat. No.
5,888,598, the disclosure of which as it relates to the preform and
container structures being expressly incorporated herein by
reference.
[0138] A polyester container preform 12 is illustrated in FIG. 2.
This preform 12 is made by injection molding or compression molding
PET based resin and comprises a threaded neck finish 112 which
terminates at its lower end in a capping flange 114. Below the
capping flange 114, there is a generally cylindrical section 116
which terminates in a section 118 of gradually increasing external
diameter so as to provide for an increasing wall thickness. Below
the section 118 there is an elongated body section 120.
[0139] The preform 12 illustrated in FIG. 2 can be stretch blow
molded to form a container 14 illustrated in FIGS. 3 and 4. The
container 14 comprises a shell 124 comprising a threaded neck
finish 126 defining a mouth 128, a capping flange 130 below the
threaded neck finish, a tapered section 132 extending from the
capping flange, a body section 134 extending below the tapered
section, and a base 136 at the bottom of the container. The
container 14 is suitably used to make a packaged beverage 138, as
illustrated in FIG. 4. The packaged beverage 138 includes a
beverage such as a carbonated soda beverage disposed in the
container 14 and a closure 140 sealing the mouth 128 of the
container.
[0140] The polyester container optionally may comprise a plurality
of layers. Those skilled in the art will appreciate that the
polyester composition comprising the polyester and gas barrier
additive may be disposed in any of the one or more layers of such
multilayer containers. For example, the polyester composition
comprising the polyester and gas barrier enhancing additive may be
disposed between two or more outer layers.
[0141] The preform 12, container 14, and packaged beverage 138 are
but examples of applications using the preforms of the present
disclosure. It should be understood that the process and apparatus
provided herein can be used to make preforms and containers having
a variety of configurations.
[0142] The present disclosure is further illustrated by the
following examples, which are not to be construed in any way as
imposing limitations upon the scope thereof. On the contrary, it is
to be clearly understood that resort may be had to various other
embodiments, modifications, and equivalents thereof which, after
reading the description therein, may suggestion themselves to those
skilled in the art without departing from the spirit of the present
invention and/or the scope of the appended claims.
EXAMPLES
Example 1
[0143] A bis(2-(benzoyloxy)ethyl) terephthalate) (hereinafter
"BPO-1") and bis(2-(benzoyloxy)ethyl)'-ethane-1,2-diyl
diisophthalate (hereinafter "BPO-2") were prepared by reacting
bis(hydroxyethyl)terephthalate (BHET) with benzoic anhydride.
BPO-1 Preparation
[0144] Dry toluene (1000 mL) was added to a dry 200 mL three neck
round bottom flask fitted with a mechanical stirrer, water cooled
condenser capped with a desicant drying tube, and a pressure
equalizing addition funnel. BHET (105.40 g, 0.415 moles) was added
to the toluene with agitation, followed by triethylamine (126.7 mL,
0.913 mol). The toluene reaction mixture was heated to 50.degree.
C. and benzoyl chloride (128.33 g) was added drop wise at a rate
sufficient to keep the reaction temperature at 90.degree. C. The
reaction mixture was maintained at 90.degree. C. with agitation
until the disappearance of the starting material was evident by
thin layer chromatography. The reaction mixture was cooled to
40.degree. C. and filtered to remove the precipitated triethylamine
hydrochloride. The filtrate was washed with an equal volume of 10%
sodium hydroxide solution followed by washing with water until a
neutral pH was measured in the wash water. The toluene was dried
with a desiccant and the solvent removed by evaporation. The
remaining solid was purified by fractional recrystallization from
chloroform using methanol.
[0145] Not wishing to be bound by any theory, it is believed that
the reaction mechanism to produce the BPO-1 proceeds as
follows:
##STR00065##
BPO-2 Preparation
[0146] The BHET (101.47 g, 0.399 mol) was stirred and heated to
140-160.degree. C. under mild vacuum conditions (20-25 torr) until
a rapid release of ethylene glycol was achieved. The resulting PET
oligomers were dissolved in p-toluene sulfonic acid (100 mg) and a
titanium catalyst Ti(OBu).sub.4 (100 mg in 50 mL toluene, 13 ppm
metal equivalent) was added (200 mL total volume added). Benzoic
anhydride (76.1 g) was added slowly, resulting in formation of a
biphasic system. A Dean-Stark trap was attached and the mixture was
refluxed until a sufficient amount of water (.about.3 mL) was
removed. The rate of water removal was significantly faster than
for the BPO-1 preparation (in less than 24 hours the water removal
was sufficient); however, the reaction was allowed to proceed for
48 hours in order to assure complete reaction. The reaction mixture
was then cooled and filtered under vacuum to remove solids. The
solids were washed with acetone and then hexanes or ether and dried
under vacuum.
[0147] Not wishing to be bound by any theory, it is believed that
the reaction mechanism to produce the BPO-2 proceeds as
follows:
##STR00066##
Analysis of Solids
[0148] The solids from both of the foregoing reactions were
analyzed using IR to identify the presence of two difference
C.dbd.O stretches and the presence of hydroxyl end groups.
Additional characterization by acid number, hydroxyl end group
determination, and GPC also were conducted.
Example 2
[0149] The relative volatility of these compounds was compared to
previously described low molecular weight gas barrier additives. A
known mass of the additive was heated in a 245.degree. C. oven for
a brief period of time, cooled, and the remaining mass evaluated.
The following table compares the resulting rate of loss of the gas
barrier additives.
TABLE-US-00001 TABLE 1 Comparison of Additive Volatility Rate of
Mass Loss Additive (% per hour) Relative Rate Caffeine 137 1 BPO-2
1.02 0.00744 BPO-1 2.41 0.0179 0.11* 0.000803* *This data reflects
the plateau region the BPO-1 showed after the initial mass
loss.
[0150] Although there were several possible sources of error (e.g.,
from the repeated heating and cooling, from the slow additional
polymerization of the samples at these high temperatures after
prolonged periods of time, and from the initial rapid mass loss due
to the possible presence of retained volatiles from the synthesis
and purification of the additive), the data illustrates the
significantly reduced rate of volatility as compared to previously
described low molecular weight additives. This reduced volatility
indicates that the proposed gas barrier additives should pose no
significant risk of plate-out or tool fouling during the injection
molding process.
Example 3
[0151] Additional experiments were conducted to evaluate potential
synthetic routes for the commercial production of BPO-1. Methods
for commercial production of BPO-1 may desirably eliminate or
significantly reduce the solvent usage while maximizing product
yield and quality.
[0152] A. BPO-1 Preparation from BHET and Methyl Benzoate
[0153] One method for preparing BPO-1 involved the direct
esterification of BHET (12.70 g, 0.0499 mol) with methyl benzoate
(14.96 g, 0.110 mol) using the catalyst TYZOR.RTM. TNBT (E.I. du
Pont de Nemours and Company, Del., United States) (0.3 g,
8.82*10.sup.-4 mol) and heated to 120.degree. C. The melt
temperature was then increased to 170.degree. C. and the reaction
was allowed to proceed for 6 hours. The methanol produced in the
reaction was distilled off and a white precipitate was separated
via filtration and analyzed using thin-layer chromatography (TLC).
The TLC analysis showed the formation of BPO-1 (16.32 g, 70%
conversion) in the presence of a monoester and unreacted BHET.
[0154] Those of skill in the art should appreciate that other
catalysts also may be used in the esterification of BHET. For
example, zirconium, hathium, titanium catalysts (other than the one
above), or the like, may be employed as the catalyst in this
process. Zirconium and hafnium catalysts that may be used include
ZrOCl.sub.2*H.sub.2O and HfCl.sub.4*2THF, respectively. The optimum
reaction conditions for the esterification may vary depending on
the catalyst used (e.g., mole ratios, catalyst levels, reaction
times, and temperatures may be adjusted as needed). It should also
be noted that the term "esterification," as used herein, refers to
both esterifications and processes commonly referred to as
"trans-esterifications."
[0155] In addition, other alkyl benzoates, including straight or
branched alkyl benzoates, may also be used in the esterification.
Benzoic acid may also be used instead of an alkyl benzoate. Not
wishing to be bound by any theory, it is believed that the
esterification reaction produces water when benzoic acid is used
instead of an alkyl benzoate. The water produced by the reaction of
benzoic acid may limit the effectiveness of the catalysts. The
esterification may also be run in the presence of a suitable
organic solvent. Non-limiting examples of suitable organic solvents
include benzene, toluene, or xylene.
[0156] B. BPO-1 Preparation from BHET and Methyl Benzoate and
Recovery Via Vacuum Distillation
[0157] Another method for preparing BPO-1 involved the reaction of
BHET (150.02 g, 0.59 mol) with methyl benzoate (321.31 g, 2.36 mol)
using the catalyst TYZOR.RTM. TPT (E.I. du Pont de Nemours and
Company, Delaware, United States) (0.24 g, 8.44*10.sup.-4 mol). The
reaction vessel was purged using nitrogen and the mixture was
gradually heated to 210.degree. C. The reaction proceeded until
methanol evolution ceased (approximately 5 hours from the start of
heatup to completion or approximately 3 hours, 50 minutes from the
start of methanol evolution). The crude reaction product was
transferred into another container and became a thick paste of
white precipitate in the excess methyl benzoate upon cooling.
Analysis of the crude reaction product dissolved in chloroform and
spotted on a TLC plate (stationary phase: neutral alumina) using a
mobile phase of chloroform showed complete conversion of the BHET
starting material to predominately BPO-1 (R.sub.f.about.0.84) with
small amounts of oligomeric material (dimer--R.sub.f.about.0.75;
trimer R.sub.f.about.0.61). The excess methyl benzoate starting
material appeared at R.sub.f.about.0.92.
[0158] The BPO-1 was isolated from the crude reaction mixture by
vacuum distillation to remove the excess methyl benzoate. A vacuum
of .about.250 mm Hg was used and the vessel temperature was kept
below 180.degree. C. to minimize the risk of distilling the BPO-1
product. Those skilled in the art will appreciate that the
temperatures and strength of the vacuum may be adjusted by a person
of skill to obtain similar results (e.g., a higher vacuum may
require a temperature well below 180.degree. C.). After removal of
the excess methyl benzoate, the product was cooled and solidified
below 105.degree. C. to give a faint yellow-white solid. Analysis
of the product by TLC indicated that the product was predominately
BPO-1 with small amounts of oligomeric material present.
[0159] This reaction and separation was repeated while modifying
several variables (e.g., temperature, catalyst weight percentage,
catalyst, and molar ratio of methyl benzoate to BHET). Each
reaction was conducted using 150 g (0.59 mol) of BHET. The weight
percentages of the catalysts in the table are based on the total
weight of the reactants. The reaction conversion is based on the
amount of evolved methanol relative to the theoretical
stoichiometric yield (37.81 g) of methanol from 150 g of BHET. The
following table depicts the percent yield of methanol, the degree
of yellow color produced, and the presence of other oligomers in
each reaction.
TABLE-US-00002 TABLE 2 Comparison of BPO-1 Reaction Conditions Mole
Temp Wt % % Yield Yellow Oligomer Ratio (.degree. C.) Cat. Catalyst
Type* MeOH Color** Present 2.25 195 0.5 TPT 50.2 -- Yes 2.25 195
0.1 TPT 46.0 ++ Yes 2.05 195 0.5 TPT 56.5 -- Yes 2.05 195 0.1 TPT
34.9 ++ Yes 2.15 195 0.3 TPT 50.2 - Yes 2.05 215 0.5 TPT 52.9 --
Yes 2.05 205 0.3 TPT 45.4 - Yes 2.05 265 1.3 TPT 81.2 ---- yes,
very high 2.05 260 0.1 TPT 73.2 ++ yes, very high 4.00 210 1.0 TPT
90.0 --- low, minor 2.50 210 1.0 TnBT 69.0 --- Yes 3.00 210 1.0 TPT
81.2 --- Yes 4.00 210 0.3 TPT 100.0 - low, minor 4.00 210 0.1 TPT
100.0 ++ low, minor 4.00 210 0.05 TPT 100.0 ++++ low, minor *TPT
(tetra-isopropyl titanate), TnBT (tetra-n-butyl titanate) **Color
grading scale: best color (++++) to worst color (----)
[0160] A number of catalysts may be employed in the esterification
reaction, as discussed hereinabove. Not wishing to be bound by any
particular theory, it is believed that minimizing the level of
catalyst, such as the titanate catalyst in the present example, may
reduce the yellowing of the reaction mixture and/or products while
maintaining good reactivity. In addition, the solubility of BPO-1
in methyl benzoate may be reduced with the use of lower catalyst
levels. This reduction in solubility may aid the separation of the
product from the excess methyl benzoate.
[0161] As previously stated, other alkyl benzoates, including
straight or branched alkyl benzoates, may be used successfully in
the esterification. Typically, an excess of alkyl benzoate is used
in the esterification reaction. Although a 2:1 molar ratio of alkyl
benzoate to BHET is sufficient to form the diester, an excess of
alkyl benzoate may be used. In the present example, a 4:1 molar
ratio of methyl benzoate is used. Any molar ratio of alkyl benzoate
to BHET in excess of 2:1 may be used so long as the reaction
conditions are adjusted to accommodate the selected excess of alkyl
benzoate. An excess may not be inefficient from a manufacturing or
economic perspective, because the excess, unreacted alkyl benzoate
may be recovered and reused in subsequent processes.
[0162] Those skilled in the art should further appreciate that this
process may be scaled up for commercial production. FIG. 5
illustrates an overall process flow including the mass balance for
the production of 100 lbs. of BPO-1. The depiction assumes
quantitative yield and high efficiency. The raw material costs of
the product may be reduced significantly due to the recovery and
recycling of methyl benzoate and sale of the methanol
byproduct.
[0163] C. BPO-1 Preparation from BHET and Benzoic Anhydride
[0164] BHET (35.09 g, 0.138 mol) and benzoic anhydride (69.39 g,
0.276 mol)(90% purity, Sigma-Aldrich) were combined at a molar
ratio of 2.0 benzoic anhydride to BHET. The vessel was purged with
nitrogen and the mixture slowly heated to 150.degree. C. A light,
yellow-colored, clear melt was achieved at 105.degree. C. As the
temperature continued to rise, crystals of benzoic acid were
observed condensing on the upper walls of the flask and at the
opening of the vertical column; however, no benzoic acid
crystallized into the column itself Upon completion of the
reaction, a heat gun was used to melt the benzoic acid crystals
back into the mixture.
[0165] The reaction mixture was sampled after 1 hour and 2 hours at
150.degree. C. to monitor progress via TLC (alumina, CHCl.sub.3).
After 1 hour, TLC indicated the presence of starting material,
benzoic acid, the monobenzoate ester of BHET, BPO-1, and BPO-2. The
BPO-1 spot was by far the largest and darkest spot observed. After
2 hours, TLC indicated the completion of reaction with the
disappearance of the starting materials and the monobenzoate ester
of BHET. The sample showed a large, dark BPO-1 spot with a small,
faint BPO-2 spot. The isolated crude product (102.99 g) solidified
below 90.degree. C. and was easily broken up and ground to a powder
after cooling to room temperature. Two different methods were then
used to remove the benzoic acid from the BPO-1: a saturated sodium
bicarbonate wash or a methanol wash.
[0166] For the sodium bicarbonate wash, the powdered crude product
(20.014 g) was mixed with 100 mL of 1 M NaHCO.sub.3 solution. The
slurry was then vacuum filtered, washed with additional NaHCO.sub.3
solution, subsequently washed with distilled water, and allowed to
dry in a vacuum oven. After drying, the solid weighed 12.201 g
(60.96% of the original crude product sample). If all the crude
product were treated in this manner, the estimated overall yield
from the NaHCO.sub.3 workup is >95%. TLC showed the NaHCO.sub.3
treated product to be substantially BPO-1 with a smaller amount of
BPO-2. The product had a melting point range of 85.degree. C. to
100.degree. C. according to a Fisher-Johns apparatus. The product
retained some of its light pink coloration (believed to be an
impurity from the benzoic anhydride).
[0167] For the methanol wash, the powdered crude product (20.007 g)
was mixed with methanol (80.005 g). The slurry was vacuum filtered,
washed with fresh methanol and placed in a vacuum oven to dry.
After drying, the solid weighed 11.264 g (56.30% of the original
crude product sample). If all the crude product were treated in
this manner, the estimated overall yield from the methanol workup
is >90%. TLC showed the methanol treated product to be primarily
BPO-1 with a small amount of BPO-2. This product gave a
Fisher-Johns melting point range of 90.degree. C. to 105.degree. C.
The methanol removed the light pink coloration from the product,
and the product had a melting point range closer to that of pure
BPO-1 (102.degree. C. to 107.degree. C.).
[0168] Not wishing to be bound by any particular theory, it is
believed that the esterification of methyl benzoate with BHET leads
to the formation of dimethyl terephthalate (DMT). DMT may form
because of the reaction conditions required to instigate the
esterification of methyl benzoate with BHET. Although the desired
product may be formed in the presence of DMT, DMT may be formed in
amounts sufficient to detrimentally affect yields of BPO-1. The
formation of DMT, however, does not occur when benzoic anhydride is
reacted with BHET.
[0169] In the present example, a molar ratio of benzoic anhydride
to BHET of 2.0 was used. Using an excess of benzoic anhydride may
be efficient from an economic and manufacturing perspective,
because any excess or unreacted benzoic acid may be recovered and
sold or re-used in future processes. FIG. 6 illustrates an overall
process flow including mass balance for the production of 100 lbs.
of BPO-1 assuming quantitative yield and high efficiency. The raw
material cost of the product should be reduced after credits for
the recovery or sale of benzoic acid are calculated.
Example 4
Preparation of Preforms and Stretch Blow Molded Containers
[0170] A polyester composition was prepared by blending a ground
1103 PET resin (Invista, Spartanburg, S.C.) with either 3 or 4 wt %
of the BPO-1 gas barrier additive. The polyester composition was
injection molded using conventional methods to obtain a container
preform. The container preforms appeared to be of good quality in
terms of clarity and shape without any indication of buildup on the
core pin or in the thread splits and other parts of the injection
molder, indicating there was no substantial plate-out on the
injection molding equipment. The container preforms then were
stretch blow molded using conventional methods to obtain bottles
which were clear, colorless to the eye, and indistinguishable from
one another.
[0171] The amount of the additive and intrinsic viscosity of the
polyester composition, preform, and container are set forth in the
table below.
TABLE-US-00003 TABLE 3 Polyester Resin and Preform Composition and
I.V. BPO-1 I.V. (wt %) (dL/g) Resin 0 0.83 Preform 0 0.78 Preform 3
0.74 Preform 4 0.72
[0172] Those skilled in the art will appreciate that the observed
decrease in I.V. with increasing amounts of gas barrier additive is
not unusual and that the I.V. could be increased by using a
polyester resin having a higher I.V.
Analysis of Container Thermal Stability
[0173] A thermal stability test was performed on the stretch blow
molded containers prepared hereinabove to measure physical changes
in container dimensions caused by temperature and pressure
stresses. Twelve test containers prepared from the control (PET+no
additive), 3 wt % additive (PET+3 wt % BPO-1), and 4 wt % additive
(PET+4 wt % BPO-1) were tested.
[0174] The dimensions of the empty containers were measured and the
containers then were filled with carbonated water to 4.1+/- volumes
and capped. The filled containers were exposed to ambient
temperature overnight and the dimensions were measured to determine
the percent change. After dimensional measurements are taken at
ambient temperature, the samples were stored in an environmental
chamber at 38.degree. C. for 24 hours and the dimensions were
measured again to determine the percent change. The minimum,
average, and standard deviation of all dimensions were calculated
for each day of testing. The average critical dimension changes are
summarized in the table below.
TABLE-US-00004 TABLE 4 Summary of Average Container Thermal
Stability Average % 3 wt % 4 wt % Expansion Control BPO-1 BPO-2
Heel Diameter 0.10% 0.10% 0.05% Pinch Diameter 4.22% 3.90% 4.42%
Pinch/Heel Ratio 4.13% 3.80% 4.38% Label Diameter 1.64% 1.98% 2.31%
Height (Support 1.97% 2.05% 2.19% Ring)
Analysis of Container Strength
[0175] The container strength of the stretch blow molded containers
prepared hereinabove also was evaluated by assessing the peak load
of the containers as well as the bottle burst pressure, expansion
volume, and percent expansion. Such tests are well known to those
skilled in the art and are briefly described below. Twelve test
containers prepared from the control (PET+no additive), 3 wt %
additive (PET+3 wt % BPO-1), and 4 wt % additive (PET+4 wt % BPO-1)
were tested.
[0176] The peak load and peak deflection of the containers were
measured with a tensile/compression tester apparatus with
non-vented steel load plates. The non-vented load plates were moved
downward until the resistance to loading peaked and the containers
lost column strength and deformed. The maximum load and location of
failure was recorded for each un-filled container at 3.75 mm (0.150
inch) deflection. If the maximum load was prior to 3.75 mm (0.150
in.) deflection, the maximum load and deflection at which it
occurred were recorded.
[0177] The burst pressure strength and the volumetric expansion of
the containers were evaluated by first pressurizing the containers
with water as quickly as possible to a pressure of 9.18 bar (135
psi). The pressure inside the containers was maintained for 13
seconds and then increased at a rate of 0.68 bar (10 psi) per
second up to a maximum of 20.4 bar (300 psi) or failure and the
burst (or failure) pressure and volumetric expansion of each
container was recorded.
TABLE-US-00005 TABLE 5 Summary of Average Container Strength
Average Container Strength Control 3 wt % BPO-1 4 wt % BPO-2 Peak
Deflection (mm) 1.446 1.571 1.446 Peak Load (g) 24686.761 24762.360
-- Burst Pressure (psi) 268.0 253.0 239.2 Expansion Volume (mL)
260.0 216.10 197.1 % Expansion 73.2 60.9 55.5
[0178] Despite the addition of the gas barrier additive to the
polyester, the container thermal stability and strength generally
were not significantly diminished as often may be observed upon the
addition of prior art gas barrier additives.
Example 5
[0179] Containers were prepared as described in Example 4
hereinabove using the above-described polyester, both alone and in
combination with 3 wt % of a gas barrier additive. The gas barrier
additives included dibenzoyl isosorbide (DBI), dicyclohexyl
terephthalate (DCT), dicyclohexyl naphthalene-2,6-dicarboxylate
(DCN), and bis(2-(benzoyloxy)ethyl) terephthalate (BPO-1).
[0180] Containers were filled with dry ice to achieve an internal
pressure of 56 psi. The loss rate of carbon dioxide from the
bottles was measured at 22.degree. C. and 50% RH using the method
described in U.S. Pat. No. 5,473,161, which is hereby incorporated
by reference in its entirety. The barrier improvement factor (BIF)
was defined as the ratio of the carbon dioxide loss rate of the
polyester container without additive divided by the carbon dioxide
loss rate of the polyester container with additive. The shelf life
of the simulated carbonated soft drink for each container also was
calculated as described by U.S. Pat. No. 5,473,161. The results are
summarized in the table below.
TABLE-US-00006 TABLE 6 Summary of Container Shelf Life and BIF 3 wt
% Control DBI 3 wt % DCT 3 wt % DCN 3 wt % BPO-1 Shelf 7.24 8.62
8.39 7.75 9.27 Life (Weeks) BIF -- 1.19 1.14 1.06 1.24
[0181] As the foregoing illustrates, the addition of the gas
barrier additives to the polyester significantly enhanced the shelf
life and gas barrier properties of containers as compared to the
containers prepared from polyester without the gas barrier
additives. Surprisingly, the addition of just 3 wt % of BPO-1
increased the container BIF by nearly 25% (1.24) and the shelf life
by two weeks.
Example 6
[0182] Containers also were prepared using the above-described
polyester, both alone and in combination with creep control agents
as set forth in co-pending U.S. application Ser. No. 12/629,657.
500 ppm or 1000 ppm of pyromellitic dianhydride (PMDA) were used as
exemplary creep control agents. The average shelf life and barrier
improvement factor of the containers were determined as described
in Example 5.
TABLE-US-00007 TABLE 7 Summary of Container Shelf Life and BIF PMDA
PMDA (500 ppm) + (500 ppm) + 3 wt % 3 wt % PMDA PMDA DCN BPO-1
Control DCN BPO-1 (500 ppm) (1000 ppm) (3 wt %) (4 wt %) Shelf Life
7.24 7.75 9.27 9.46 9.01 7.62 10.04 (Weeks) BIF -- 1.06 1.24 1.13
1.19 1.09 1.39
[0183] Applicants surprisingly have discovered that the embodiments
of the claimed gas barrier additives not only enhance the container
gas barrier properties and shelf life, but also provide an additive
effect when combined with certain creep control agents. As the
foregoing illustrates, the gas barrier additive (BPO-1) and creep
control agent (PMDA) improved the container BIF by over 10% (1.24
to 1.39) and the shelf life by over half a week (9.46 to
10.04).
Example 7
[0184] Containers also were prepared using other polyester resins
in combination with gas barrier enhancing additives and/or creep
control agents. The other polyester resins included 1103 A
(Invista, Spartanburg, S.C.) and MMP 804 (PET Processors L.L.C.,
Painesville, Ohio).
[0185] A CO.sub.2 permeation test was used to determine the shelf
life of the containers. The bottles were filled with carbonated
water at 4.2 v/v and the loss rate of loss rate of carbon dioxide
from the bottles was measured at 22.degree. C. and 50% RH using
QuantiPerm. The permeation rates (mL/pkg/day) were used to
calculate the percentage loss of carbonation per week and shelf
life. The sorption also was estimated by the QuantiPerm software
and the percentage of volume expansion was measured for each
container.
TABLE-US-00008 TABLE 8 Summary of Container Shelf Life % CO.sub.2
Polyester % loss/ Sorption Shelf life Composition Expansion week %
(weeks) BIF 1103 A Resin 6.26 2.54 1.59 6.31 -- 1103 A Resin + 4.86
2.24 1.63 7.79 1.13 500 ppm PMDA 1103 A Resin + 7.42 2.20 1.57 6.72
1.15 500 ppm PMDA + 4% BPO-1 MMP 804 Resin 4.36 2.53 1.98 6.97 --
MMP 804 Resin + 5.11 1.92 1.96 8.78 1.32 3% DBI MMP 804 Resin +
4.64 1.88 1.97 9.21 1.35 3% DBI + 500 ppm PMDA
[0186] As can be seen from the foregoing, the addition of the gas
barrier additive and creep control agent significantly increased
the shelf life of containers prepared from different types of
polyester resins.
Example 8
[0187] The mechanical properties of the containers of Examples 5
and 6 also were evaluated by measuring the creep of the containers.
The average percent bottle creep is displayed in Table 9 and
illustrated in FIG. 7.
TABLE-US-00009 TABLE 9 Summary of Container Creep Over 8 Weeks
Averaged % Bottle Creep After Variable Fill 1 Wk. 2 Wks. 3 Wks. 4
Wks. 5 Wks. 6 Wks. 7 Wks. 8 Wks. Control 3.78 5.58 5.35 5.23 5.42
5.29 5.24 5.43 3 wt % DBI 3.47 5.64 5.64 4.93 5.42 5.31 5.26 5.19
5.45 3 wt % DCT 3.36 5.31 5.89 5.06 5.37 5.19 5.36 5.22 5.11 3 wt %
DCN 3.47 5.24 5.13 5.26 5.37 5.27 5.07 5.28 5.09 3 wt % BPO-1 3.35
4.99 5.07 4.80 4.80 5.27 5.04 4.86 4.71 PMDA (500 ppm) 2.81 4.20
4.37 4.37 4.23 4.17 4.16 4.40 4.46 PMDA (1000 ppm) 3.14 4.61 4.65
4.76 4.72 4.57 4.68 4.83 4.85 PMDA (500 ppm) + 3.44 5.85 5.68 5.64
6.05 5.43 5.56 5.45 5.48 DCN (3 wt %) PMDA (500 ppm) + 3.67 5.56
5.82 5.53 5.48 5.51 5.94 5.60 5.99 BPO-1 (4 wt %)
[0188] As can be seen from the foregoing, the addition of the gas
barrier additive did not significantly increase the creep of the
containers. Surprisingly, the gas barrier additive BPO-1 showed a
reduced average percent bottle creep over the entire 8 week period
as compared to the container made from a polyester with no
additives, indicating that the gas barrier additive did not
significantly impair the container's mechanical properties.
Example 9
[0189] The aesthetics of the containers from Examples 5 and 6 also
were evaluated by measuring the color and clarity of the
containers. The colors of the containers were measured with a
Hunter lab colorimeter. The results are shown in Table 10. Hunter
L*,a *,b* color space is a 3-dimensional rectangular color space
based on the opponent-colors theory and expanded in the yellow
region, wherein on the L* (lightness) axis white is 100 and black
is 0, wherein on the a* (red-green) axis red is positive, green is
negative, and neutral is 0; and wherein on the b* (blue-yellow)
axis yellow is positive, blue is negative, and neutral is 0. DE* is
a measure of the total color difference, calculated by taking the
square root of the sum of the squares of the changes in L*,a*,b*.
The data in Table 10 represent the average of 9 measurements.
TABLE-US-00010 TABLE 10 Analysis of Container Haze L* a* b* Haze dE
* ab Variable (D65) (D65) (D65) (D1003-95) (C.) (D65) Control 94.85
-0.046 0.821 1.236 0.096 3 wt % DBI 94.91 -0.040 0.830 1.161 0.111
3 wt % DCT 94.73 -0.016 0.650 2.308 0.207 3 wt % DCN 94.95 0.016
0.687 1.489 0.226 3 wt % BPO-1 94.86 -0.032 0.688 1.232 0.169 PMDA
(500 ppm) 94.87 -0.043 0.787 1.227 0.088 PMDA (1000 ppm) 94.69
-0.014 1.017 1.448 0.329 PMDA (500 ppm) + 94.83 0.016 0.656 1.688
0.200 DCN (3 wt %) PMDA (500 ppm) + 94.79 -0.037 0.771 1.252 0.089
BPO-1 (4 wt %)
[0190] As can be seen from the foregoing, the use of the proposed
gas barrier additives generally does not significantly impair the
aesthetic appearance of the containers. In particular, the
combination of the gas barrier additive (BPO-1) and creep control
agent (PMDA) surprisingly had a insubstantial color difference as
compared to the container made from the polyester without
additives.
Example 10
Preparation of Preforms and Stretch Blow Molded Containers
Containing PEM
[0191] A polyester composition was prepared by blending a ground
1103 A polyester resin (Invista, Spartanburg, S.C.) with either 3
or 4 wt % of PEM, a gas barrier additive having the chemical
formula:
##STR00067##
[0192] The polyester composition was injection molded using
conventional methods to obtain a container preform. The container
preforms appeared to be of good quality in terms of clarity and
shape without any indication of buildup on the core pin or in the
thread splits and other parts of the injection molder, indicating
there was no substantial plate-out on the injection molding
equipment. The container preforms then were stretch blow molded
using conventional methods to obtain bottles which were clear,
colorless to the eye, and indistinguishable from one another.
[0193] The amount of the additive and intrinsic viscosity (I.V.) of
the polyester composition, preform, and container are set forth in
the table below.
TABLE-US-00011 TABLE 11 Polyester Composition and Preform I.V.
Intrinsic Viscosity Polyester Composition (I.V.) (dL/g) 1103 A
Resin 0.83 1103 A Preform 0.80 1103 A Resin + 3% PEM-1 Preform 0.79
1103 A Resin + 4% PEM-1 Preform 0.79 1103 A Resin + 4% PEM-1 + 0.84
750 ppm PMDA
[0194] As the foregoing illustrates, an acceptable I.V. loss of
0.03 dL/g was achieved during the conversion of the resins into
preforms. No significant difference in I.V. was observed between
the 1103 A control preforms and the preforms molded with 3% and 4%
PEM-1. The I.V. of the preforms produced with PMDA at 750 ppm and
PEM-1 at 4% was considerably higher than those molded without
PMDA.
[0195] Those skilled in the art will appreciate that the observed
decrease in I.V. with increasing amounts of gas barrier additive is
not unusual and that the I.V. could be increased by using a
polyester resin having a higher I.V.
Example 11
[0196] Containers were prepared using conventional methods using
the polyester compositions in Example 10 and evaluated using the
methods described in Example 7. The results are summarized in the
table below.
TABLE-US-00012 TABLE 12 Shelf life and Barrier Improvement Factor
(BIF) Results Polyester % CO2 % Sorption Shelf life Composition
Expansion loss/week % (wks.) BIF Control 3.72 1.881 1.99 10.7 1.00
3% PEM-1 3.79 1.623 1.99 12.2 1.18 4% PEM-1 3.78 1.597 1.99 12.4
1.17 4% PEM-1 & 3.92 1.523 1.99 12.9 1.25 750 ppm PMDA
[0197] As the foregoing illustrates, the addition of the gas
barrier additives to the polyester significantly enhanced the shelf
life and gas barrier properties of containers as compared to the
containers prepared from polyester without the gas barrier
additives. Surprisingly, the addition of just 3 wt % of PEM-1
increased the container BIF by nearly 20% (1.18) and the shelf life
by approximately two weeks.
[0198] It should be apparent that the foregoing relates only to the
preferred embodiments of the present disclosure and that numerous
changes and modification may be made herein without departing from
the spirit and scope of the invention as defined by the following
claims and equivalents thereof.
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