U.S. patent application number 14/305411 was filed with the patent office on 2014-10-02 for aliphatic polyester coating compositions containing tetramethyl cyclobutanediol.
This patent application is currently assigned to EASTMAN CHEMICAL COMPANY. The applicant listed for this patent is EASTMAN CHEMICAL COMPANY. Invention is credited to Angela Hartley Honeycutt, Stacey James Marsh.
Application Number | 20140296407 14/305411 |
Document ID | / |
Family ID | 42034500 |
Filed Date | 2014-10-02 |
United States Patent
Application |
20140296407 |
Kind Code |
A1 |
Marsh; Stacey James ; et
al. |
October 2, 2014 |
ALIPHATIC POLYESTER COATING COMPOSITIONS CONTAINING TETRAMETHYL
CYCLOBUTANEDIOL
Abstract
Disclosed are aliphatic polyester resins containing
2,2,4,4-tetramethyl-1,3-cyclobutanediol and solvent borne,
thermosetting coating compositions prepared therefrom. The
aliphatic polyesters exhibit good hardness and flexibility when
formulated into thermosetting coatings compositions.
Inventors: |
Marsh; Stacey James; (Church
Hill, TN) ; Honeycutt; Angela Hartley; (Kingsport,
TN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
EASTMAN CHEMICAL COMPANY |
Kingsport |
TN |
US |
|
|
Assignee: |
EASTMAN CHEMICAL COMPANY
Kingsport
TN
|
Family ID: |
42034500 |
Appl. No.: |
14/305411 |
Filed: |
June 16, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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12367190 |
Feb 6, 2009 |
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14305411 |
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Current U.S.
Class: |
524/317 ;
528/307 |
Current CPC
Class: |
C08K 5/34922 20130101;
C08G 18/72 20130101; C08K 5/3477 20130101; C08G 18/792 20130101;
C08G 18/4241 20130101; C09D 167/02 20130101; C08G 63/20 20130101;
C08G 63/16 20130101; C09D 7/63 20180101; C08K 3/013 20180101; C08L
2666/18 20130101; C08K 5/29 20130101; C08G 18/423 20130101; C08L
33/062 20130101; C08G 63/199 20130101; C09D 175/06 20130101; C09D
167/00 20130101; C08G 18/4238 20130101; C09D 167/00 20130101; C08L
2666/04 20130101 |
Class at
Publication: |
524/317 ;
528/307 |
International
Class: |
C08G 63/16 20060101
C08G063/16; C09D 7/12 20060101 C09D007/12 |
Claims
1. A curable, aliphatic polyester, comprising: i. diacid residues,
comprising about 50 to 100 mole percent of a cycloaliphatic
dicarboxylic acid; ii. diol residues, comprising about 50 to 100
mole percent, based on the total moles of diol residues, of the
residues of 2,2,4,4-tetramethyl-1,3-cyclobutanediol; and iii. about
2 to about 40 mole percent of the residues of at least one polyol,
based on the total moles of diol and polyol residues; wherein said
curable, aliphatic polyester contains 90 or greater mole percent
aliphatic diacid residues based on the total moles of diacid
residues, and wherein said curable, aliphatic polyester has a
number average molecular weight of about 300 to about 10,000
daltons, a hydroxyl number of about 20 to about 450 mg KOH/g of
polyester, and an acid number of 0 to about 80 mg KOH/g of
polyester.
2. The curable, aliphatic polyester according to claim 1 wherein
said diacid residue comprises about 50 to about 100 mole percent of
the residues of at least one cycloaliphatic dicarboxylic acid
chosen from 1,4-cyclohexanedicarboxylic acid,
1,3-cyclohexanedicarboxylic acid, hexahydrophthalic anhydride, and
about 50 to about 0 mole percent of the residues at least
one-acyclic aliphatic dicarboxylic acid chosen from adipic acid,
dodecanedioic acid, sebacic acid, azelaic acid, succinic acid, and
glutaric acid; and said diol residues comprise about 50 to 0 mole
percent of the residues of at least one diol chosen from neopentyl
glycol, ethylene glycol, propylene glycol, diethylene glycol,
triethylene glycol, tetraethylene glycol, pentaethylene glycol,
hexaethylene glycol, heptaethylene glycol, octaethylene glycol,
nonaethylene glycol, decaethylene glycol, 1,3-propanediol,
2,4-dimethyl-2-ethyl-hexane-1,3-diol, 2,2-dimethyl-1,2-propanediol,
2-ethyl-2-butyl-1,3-propanediol,
2-ethyl-2-isobutyl-1,3-propanediol, 1,3-butanediol, 1,4-butanediol,
1,5-pentanediol, 1,6-hexanediol, 2,2,4-trimethyl-1,6-hexanediol,
thiodiethanol, 1,2-cyclohexanedimethanol,
1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol,
2,2,4-trimethyl 1,3-pentanediol, p-xylenediol, hydroxypivalyl
hydroxypivalate, 1,10-decanediol, and hydrogenated bisphenol A.
3. The curable, aliphatic polyester according to claim 2 wherein
said diacid residues comprise about 50 to about 100 mole percent of
the residues of 1,4-cyclohexanedicarboxylic acid, hexahydrophthalic
anhydride, or a mixture thereof, and about 0 to about 50 mole
percent of the residues of adipic acid; and said diol residues
comprise about 50 to 0 mole percent of the residues of neopentyl
glycol.
4. The curable, aliphatic polyester according to claim 3 wherein
said diacid residues comprise about 100 mole percent of the
residues of hexahydrophthalic anhydride; and said diol residues
comprise, about 50 to 100 mole percent of the residues of
2,2,4,4-tetramethyl-1,3-cyclobutanediol, and about 50 to 0 mole
percent of the residues of neopentyl glycol.
5. The curable, aliphatic polyester according to claim 1 which
comprises about 3 to about 30 mole percent of the residues of at
least one polyol selected from trimethylolpropane, pentaerythritol,
trimethylolethane, erythritol, threitol, dipentaerythritol,
sorbitol, and glycerine.
6. The curable, aliphatic polyester according to claim 1 which has
a Tg of about -35 to about 35.degree. C.
7. The curable, aliphatic polyester according to claim 1 which has
a hydroxyl number of about 30 to about 250 mg KOH/g of polyester,
an acid number of about 2 to about 15 mg KOH/g of polyester, a
number average molecular weight of about 700 to about 7000 daltons,
and a Tg of about -35 to about 35.degree. C.
8. A thermosetting coating composition, comprising: (A). about 50
to about 90 weight percent, based on the total weight of (A) and
(B) of at least one curable, aliphatic polyester, comprising i.
diacid residues, comprising about 50 to 100 mole percent of a
cycloaliphatic dicarboxylic acid; ii. diol residues, comprising
about 50 to 100 mole percent, based on the total moles of diol
residues, of the residues of
2,2,4,4-tetramethyl-1,3-cyclobutanediol; and iii. about 2 to about
40 mole percent of the residues of at least one polyol, based on
the total moles of diol and polyol residues; wherein said curable,
aliphatic polyester contains 90 or greater mole percent aliphatic
diacid residues based on the total moles of diacid residues, and
wherein said curable, aliphatic polyester has a number average
molecular weight of about 300 to about 10,000 daltons, a hydroxyl
number of about 20 to about 450 mg KOH/g of polyester, and an acid
number of 0 to about 80 mg KOH/g of polyester; (B). about 10 to
about 50 weight percent, based on the total weight of (A) and (B)
of a crosslinker comprising at least one compound reactive with a
carboxylic acid or a hydroxyl group; (C). about 10 to about 60
weight percent, based on the total weight of (A), (B), and (C) of
at least one nonaqueous solvent.
9. The coating composition according to claim 8 wherein said
curable, aliphatic polyester comprises diacid residues comprising
about 50 to about 100 mole percent of the residues of at least one
cycloaliphatic dicarboxylic acid is chosen from
1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid
and hexahydrophthalic anhydride, and about 50 to about 0 mole
percent of the residues at least one acylic aliphatic dicarboxylic
acid chosen from adipic acid, dodecanedioic acid, sebacic acid,
azelaic acid, succinic acid, and glutaric acid; and diol residues
comprising about 50 to 0 mole percent of the residues of at least
one diol chosen from neopentyl glycol, ethylene glycol, propylene
glycol, diethylene glycol, triethylene glycol, tetraethylene
glycol, pentaethylene glycol, hexaethylene glycol, heptaethylene
glycol, octaethylene glycol, nonaethylene glycol, decaethylene
glycol, 1,3-propanediol, 2,4-dimethyl-2-ethyl-hexane-1,3-diol,
2,2-dimethyl-1,2-propanediol, 2-ethyl-2-butyl-1,3-propanediol,
2-ethyl-2-isobutyl-1,3-propanediol, 1,3-butanediol, 1,4-butanediol,
1,5-pentanediol, 1,6-hexanediol, 2,2,4-trimethyl-1,6-hexanediol,
thiodiethanol, 1,2-cyclohexanedimethanol,
1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol,
2,2,4-trimethyl 1,3-pentanediol, p-xylenediol, hydroxypivalyl
hydroxypivalate, 1,10-decanediol, and hydrogenated bisphenol A.
10. The coating composition according to claim 9 wherein said
diacid residues comprise about 50 to about 100 mole percent of the
residues of 1,4-cyclohexanedicarboxylic acid, hexahydrophthalic
anhydride, or a mixture thereof, and about 50 to about 0 mole
percent of the residues of adipic acid; and said diol residues
comprise about 50 to 0 mole percent of the residues of neopentyl
glycol.
11. The coating composition according to claim 8 wherein said
curable, aliphatic polyester has a Tg of about -35 to about
35.degree. C.
12. The coating composition according to claim 8 wherein said
curable, aliphatic polyester comprises about 3 to about 30 mole
percent of the residues of at least one polyol selected from
trimethylolpropane, pentaerythritol, trimethylolethane, erythritol,
threitol, dipentaerythritol, sorbitol, and glycerine.
13. The coating composition according to claim 8 wherein said
curable, aliphatic polyester has a hydroxyl number of about 30 to
about 250 mg potassium hydroxide per gram of polyester, an acid
number of about 2 to about 15 mg potassium hydroxide per gram of
polyester, and a number average molecular weight of about 700 to
about 7000 daltons, and a Tg of about -35 to about 35.degree.
C.
14. The coating composition according to claim 8 wherein said
crosslinker comprises at least one compound chosen from melamines,
isocyanates, and isocyanurates.
15. The coating composition according to claim 14 wherein said
crosslinker comprises at least one melamine compound chosen from
hexamethoxymethylmelamine, tetramethoxymethylbenzoguanamine,
tetramethoxymethylurea, and mixed butoxy/methoxy substituted
melamines.
16. The coating composition according to claim 14 wherein said
crosslinker comprises isocyanurates of 1,6-hexamethylene
diisocyanate, the biuret of 1,6-hexamethylene diisocyanate, the
trimer of 1,6-hexamethylene diisocyanate, or combinations
thereof.
17. The coating composition according to claim 8 wherein said
nonaqueous solvent comprises benzene, xylene, mineral spirits,
naptha, toluene, acetone, methyl ethyl ketone, methyl n-amyl
ketone, methyl isoamyl ketone, n-butyl acetate, isobutyl acetate,
t-butyl acetate, n-propyl acetate, isopropyl acetate, ethyl
acetate, methyl acetate, ethanol, n-propanol, isopropanol,
n-butanol, sec-butanol, isobutanol, ethylene glycol monobutyl
ether, propylene glycol n-butyl ether, propylene glycol methyl
ether, propylene glycol monopropyl ether, dipropylene glycol methyl
ether, diethylene glycol monobutyl ether, trimethylpentanediol
mono-isobutyrate, ethylene glycol mono-octyl ether, diacetone
alcohol, 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, or
combinations thereof.
18. A shaped object coated with the coating composition of claim 8.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent
application Ser. No. 12/367,190, filed on Feb. 6, 2009, the
disclosure of which is incorporated herein by reference in its
entirety.
FIELD OF THE INVENTION
[0002] This invention pertains to aliphatic, curable polyesters for
solvent-borne, thermosetting coating compositions. More
particularly, this invention pertains to curable polyesters
containing 2,2,4,4-tetramethyl-1,3-cyclobutanediol and high-solids,
solvent-borne thermosetting coating compositions prepared from
these polyesters. These polyesters can be used in blends with
acrylic resins or serve as the primary film former in a coating
formulation.
BACKGROUND OF THE INVENTION
[0003] Solvent-borne, polyester thermosetting coatings that exhibit
high hardness are desirable. Coatings with high hardness typically
exhibit high gloss, good distinctness of image (DOI), fast
dry-times, scratch, stain, chemical, and humidity resistance, and
outdoor durability.
[0004] Aliphatic polyesters are frequently used to reduce viscosity
and increase solids for thermosetting acrylic (abbreviated herein
as "TSA") coatings. Aliphatic polyesters also are useful as a
primary film former in high solids coatings because of their
ability to reduce volatile organic compound ("VOC") emissions.
Coatings made from aliphatic polyesters are generally flexible but
tend to be soft, which results in poor resistance to solvents and
chemicals, poor humidity resistance and poor outdoor
durability.
[0005] Hardness and hardness-related properties of aliphatic
polyester resins sometimes can be improved with the addition of
1,4-cyclohexanedimethanol (abbreviated herein as "CHDM") and
hydrogenated bisphenol A (abbreviated herein as "HBPA").
Unfortunately, poor solvent solubility and compatibility with
acrylic resins often are observed as CHDM content is increased in
the polyester resin formulation. The amount of CHDM that can be
incorporated into the resin formulation, therefore is limited. HBPA
is know to exhibit similar characteristics.
[0006] Poor resin solubility often manifests itself over time by
phase separation, precipitation of the resin from solution, and the
development of hazy to opaque resin solutions. These
characteristics are undesirable and limit the storage stability of
the resin solution and the coatings formulated from these
solutions. Such coatings, for example, may experience a viscosity
increase, phase separation, agglomeration of ingredients, etc.,
that result in an undesirable higher application viscosity, poor
appearance and poor mechanical properties of the cured film.
[0007] Thermosetting acrylic ("TSA") resins are widely used in
industrial coatings. They can be formulated to a high glass
transition temperature (Tg) and exhibit excellent light stability
and hydrolysis resistance. These properties result in coatings with
the desirable characteristics of high hardness; fast dry times;
resistance to stains, chemicals and humidity; and good outdoor
durability. Consequently, TSA resins often serve as the primary
film-former in coatings for demanding applications that include
transportation, maintenance, marine and building/construction
markets.
[0008] Although TSA resins exhibit many desirable properties, they
often lack flexibility and require more solvent in the coating
formulation to achieve a practical application viscosity. The
higher solvent requirement for TSA resins makes it difficult to
achieve high solids coatings with reduced VOC content as mandated
by various federal and state air quality organizations.
[0009] To increase resin and coating solids, reduce viscosity, and
lower VOC emission, aliphatic polyester resins can be blended with
TSA resins. Unfortunately, the glass transition temperature ("Tg")
of the blend frequently decreases significantly as the polyester
content increases. The lower Tg of the blend has an adverse impact
on the desirable characteristics that the TSA resin imparts to the
coating.
[0010] There is a need in the coatings industry for aliphatic
polyesters that exhibit good hardness with good flexibility and
solubility when formulated into thermosetting coatings
compositions. In addition, there is a need for aliphatic polyester
resins that, when blended with TSA resins, lower the viscosity
while maintaining the Tg of the TSA resin in high solids,
thermosetting coating compositions.
SUMMARY OF THE INVENTION
[0011] The present invention provides curable, aliphatic polyesters
prepared from 2,2,4,4-tetramethyl-1,3-cyclobutanediol. Thus, one
embodiment of our invention is a curable, aliphatic polyester,
comprising: [0012] i. diacid residues, comprising at least 90 mole
percent, based on the total moles of diacid residues, of the
residues of at least one aliphatic diacid, the aliphatic
dicarboxylic acid comprising about 50 to 100 mole percent of a
cycloaliphatic dicarboxylic acid; [0013] ii. diol residues,
comprising about 50 to 100 mole percent, based on the total moles
of diol residues, of the residues of
2,2,4,4-tetramethyl-1,3-cyclobutanediol; and [0014] iii. about 2 to
about 40 mole percent of the residues of at least one polyol, based
on the total moles of diol and polyol residues; wherein the
curable, aliphatic polyester has a number average molecular weight
of about 300 to about 10,000 daltons, a glass transition
temperature of about -35.degree. C. to about 35.degree. C., a
hydroxyl number of about 20 to about 450 mg KOH/g of polyester, and
an acid number of 0 to about 80 mg KOH/g of polyester.
[0015] Coatings formulated from these all aliphatic polyester
resins can exhibit high gloss, distinctness of image and
reflectivity; good hardness with good flexibility; solvent and
chemical resistance; and good gloss retention during UV and
humidity exposure for good outdoor durability. Thus, another
embodiment of our invention is a thermosetting coating composition,
comprising: [0016] (A). about 50 to about 90 weight percent, based
on the total weight of (A) and (B) of at least one curable,
aliphatic polyester, comprising [0017] i. diacid residues,
comprising at least 90 mole percent, based on the total moles of
diacid residues, of the residues of at least one aliphatic diacid,
the aliphatic dicarboxylic acid comprising about 50 to 100 mole
percent of a cycloaliphatic dicarboxylic acid; [0018] ii. diol
residues, comprising about 50 to 100 mole percent, based on the
total moles of diol residues, of the residues of
2,2,4,4-tetramethyl-1,3-cyclobutanediol; and [0019] iii. about 2 to
about 40 mole percent of the residues of at least one polyol, based
on the total moles of diol and polyol residues; [0020] wherein the
curable, aliphatic polyester has a number average molecular weight
of about 300 to about 10,000 daltons, a glass transition
temperature of about -35.degree. C. to about 35.degree. C., a
hydroxyl number of about 20 to about 450 mg KOH/g of polyester, and
an acid number of 0 to about 80 mg KOH/g of polyester; [0021] (B).
about 10 to about 50 weight percent, based on the total weight of
(A) and (B) of a crosslinker comprising at least one compound
reactive with a carboxylic acid or a hydroxyl group; [0022] (C).
about 10 to about 60 weight percent, based on the total weight of
(A), (B), and (C) of at least one nonaqueous solvent.
[0023] The aliphatic polyesters may be blended with acrylics or
serve as the primary film former to formulate factory and
field-applied coatings used in auto OEM, auto refinish,
transportation, aerospace, maintenance, marine, machinery and
equipment, general metal, appliance, metal furniture, plastic and
building/construction applications. When blended with thermosetting
acrylic (TSA) resins, our aliphatic polyesters exhibit good
solubility, compatibility and viscosity reduction with good Tg
retention of the blend.
DETAILED DESCRIPTION
[0024] We have found that curable, aliphatic polyesters that
contain 2,2,4,4-tetramethyl-1,3-cyclobutanediol (abbreviated herein
as "TMCD") can be used to prepare solvent-borne, high-solids,
thermosetting coatings that exhibit high gloss, good hardness and
flexibility; and solvent and chemical resistance. These aliphatic
polyesters also can be blended with thermosetting acrylic resins
("TSA") to produce blends that have low viscosity, good
compatibility, flexibility, and Tg retention. Thus, in a general
embodiment, our invention provides a curable, aliphatic polyester,
comprising: [0025] i. diacid residues, comprising at least 90 mole
percent, based on the total moles of diacid residues, of the
residues of at least one aliphatic diacid, the aliphatic
dicarboxylic acid comprising about 50 to 100 mole percent of a
cycloaliphatic dicarboxylic acid; [0026] ii. diol residues,
comprising about 50 to 100 mole percent, based on the total moles
of diol residues, of the residues of
2,2,4,4-tetramethyl-1,3-cyclobutanediol; and [0027] iii. about 2 to
about 40 mole percent of the residues of at least one polyol, based
on the total moles of diol and polyol residues; wherein the
curable, aliphatic polyester has a number average molecular weight
of about 300 to about 10,000 daltons, a glass transition
temperature of about -35.degree. C. to about 35.degree. C., a
hydroxyl number of about 20 to about 450 mg KOH/g of polyester, and
an acid number of 0 to about 80 mg KOH/g of polyester. Another
aspect of the invention is a solvent borne thermosetting coating
formulation comprising the above aliphatic polyester resin. The
coating formulation may, optionally, comprise a crosslinker,
various additives and pigments.
[0028] Unless otherwise indicated, all numbers expressing
quantities of ingredients, properties such as molecular weight,
reaction conditions, and so forth used in the specification and
claims are to be understood as being modified in all instances by
the term "about." Unless indicated to the contrary, the numerical
parameters set forth in the following specification and attached
claims are approximations that may vary depending upon the desired
properties sought to be obtained by the present invention. At the
very least, each numerical parameter should be construed in light
of the number of reported significant digits and by applying
ordinary rounding techniques. Further, the ranges stated in this
disclosure and the claims are intended to include the entire range
specifically and not just the endpoint(s). For example, a range
stated to be 0 to 10 is intended to disclose all whole numbers
between 0 and 10 such as, for example 1, 2, 3, 4, etc., all
fractional numbers between 0 and 10, for example 1.5, 2.3, 4.57,
6.1113, etc., and the endpoints 0 and 10. Also, a range associated
with chemical substituent groups such as, for example, "C.sub.1 to
C.sub.5 diols", is intended to specifically include and disclose
C.sub.1 and C.sub.5 diols as well as C.sub.2, C.sub.3, and C.sub.4
diols.
[0029] Notwithstanding that the numerical ranges and parameters
setting forth the broad scope of the invention are approximations,
the numerical values set forth in the specific examples are
reported as precisely as possible. Any numerical value, however,
inherently contains certain errors necessarily resulting from the
standard deviation found in its respective testing
measurements.
[0030] As used in the specification and the appended claims, the
singular forms "a," "an" and "the" include their plural referents
unless the context clearly dictates otherwise. For example, a
reference to a "polyester," a "dicarboxylic acid", a "residue" is
synonymous with "at least one" or "one or more" polyesters,
dicarboxylic acids, or residues and is thus intended to refer to
both a single or plurality of polyesters, dicarboxylic acids, or
residues. In addition, references to a composition containing or
including "an" ingredient or "a" polyester is intended to include
other ingredients or other polyesters, respectively, in addition to
the one named. The terms "containing" or "including" are intended
to be synonymous with the term "comprising", meaning that at least
the named compound, element, particle, or method step, etc., is
present in the composition or article or method, but does not
exclude the presence of other compounds, catalysts, materials,
particles, method steps, etc, even if the other such compounds,
material, particles, method steps, etc., have the same function as
what is named, unless expressly excluded in the claims.
[0031] Also, it is to be understood that the mention of one or more
process steps does not preclude the presence of additional process
steps before or after the combined recited steps or intervening
process steps between those steps expressly identified. Moreover,
the lettering of process steps or ingredients is a convenient means
for identifying discrete activities or ingredients and the recited
lettering can be arranged in any sequence, unless otherwise
indicated.
[0032] The term "curable, aliphatic polyester", as used herein, is
synonymous with the term "resin" and is intended to mean a
thermosetting surface coating polymer prepared by the
polycondensation of one or more acid components, diol components,
and polyol components. The curable, aliphatic polyester of the
present invention is a thermoset polymer and is suitable as a resin
for solvent-based coatings. This polyester has a low molecular
weight, typically about 300 to about 10,000 daltons, and would not
be suitable for the fabrication films, sheets, and other shaped
objects by extrusion, casting, blow molding, and other
thermoforming processes commonly used for high molecular weight
thermoplastic polymers. The polyester has a reactive functional
group, typically a hydroxyl group or carboxyl group for the purpose
of later reacting with a crosslinker in a coating formulation. The
functional group is controlled by having either excess diol or acid
(from dicarboxylic acid or tricarboxylic acid) in the polyester
resin composition. The desired crosslinking pathway will determine
whether the polyester resin will be hydroxyl-terminated or
carboxylic acid-terminated. This concept is known to those skilled
in the art and described, for example, in Organic Coatings Science
and Technology, 2nd ed., p. 246-257, by Z. Wicks, F. Jones, and S.
Pappas, Wiley, New York, 1999.
[0033] Typically, the acid component comprises at least one
dicarboxylic acid and may, optionally, include mono- and polybasic
carboxylic acids. For example, the curable, aliphatic polyester may
be prepared from an acid component comprising an aliphatic or
cycloaliphatic dicarboxylic acid such as, for example, adipic acid
or 1,3-cyclohexanedicarboxylic acid, or a mixture of one or more
aliphatic and cycloaliphatic acids. The diol component may comprise
one or more cycloaliphatic diols such as, for example,
2,2,4,4-tetramethyl-1,3-cyclobutanediol, either alone or in
combination with one or more linear or branched aliphatic diols
such as, for example, neopentyl glycol. Catalysts may be used to
accelerate the rate of the polycondensation reaction. Additional
examples of each of the components of the curable, aliphatic
polyester include those known in the art including, but not limited
to, those discussed below, and in various documents known in the
art such as, for example, in Resins for Surface Coatings, Vol. III,
p. 63-167, ed. by P. K. T. Oldring and G. Hayward, SITA Technology,
London, UK, 1987.
[0034] The term "residue", as used herein in reference to the
polymers of the invention, means any organic structure incorporated
into a polymer through a polycondensation or ring opening reaction
involving the corresponding monomer. It will also be understood by
persons having ordinary skill in the art, that the residues
associated within the various curable polyesters of the invention
can be derived from the parent monomer compound itself or any
derivative of the parent compound. For example, the dicarboxylic
acid residues referred to in the polymers of the invention may be
derived from a dicarboxylic acid or its associated acid halides,
esters, salts, anhydrides, or mixtures thereof. Thus, as used
herein, the term "dicarboxylic acid" is intended to include
dicarboxylic acids and any derivative of a dicarboxylic acid,
including its associated acid halides, esters, half-esters, salts,
half-salts, anhydrides, mixed anhydrides, or mixtures thereof,
useful in a polycondensation process with a diol to make a curable,
aliphatic polyester.
[0035] The term "aliphatic" is intended to have its common meaning
as would be understood by persons having ordinary skill in the art,
that is, acyclic or cyclic, saturated or unsaturated carbon
compounds, excluding benzenoid or other aromatic systems. The term
"cycloaliphatic", as used herein, is intended to mean an aliphatic,
cyclic compound. The term "aliphatic polyester", as used herein, is
understood to mean a polyester that contains 90 or greater mole
percent aliphatic diacid or diol residues, based on the total moles
of diacid or diol residues. Small amounts (i.e., 10 mole percent or
less) of aromatic dicarboxylic acids or aromatic diols also may be
present.
[0036] The curable, aliphatic polyester comprises diacid residues,
that comprise at least 90 mole percent, based on the total moles of
diacid residues, of the residues of at least one aliphatic diacid
which, in turn, comprises about 50 to 100 mole percent of a
cycloaliphatic dicarboxylic acid. Some examples of aliphatic and
cycloaliphatic dicarboxylic acids include, but are not limited to,
adipic acid, dodecanedioic acid, sebacic acid, azelaic acid,
1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid,
hexahydrophthalic anhydride, tetrahydrophthalic anhydride succinic
acid, glutaric acid, and combinations thereof. For example, the
curable, aliphatic polyester can comprise about 50 mole percent of
the residues of 1,4-cyclohexanedicarboxylic acid and about 50 mole
percent of the residues of adipic acid, based on the total moles of
diacid residues. In another example, the curable, aliphatic
polyester can contain about 50 mole percent of the residues of
hexahydrophthalic anhydride and about 50 mole percent of the
residues of adipic acid.
[0037] Some additional, non-limiting examples of the diacid
component of the curable, aliphatic polyester are as follows: (a)
about 50 to about 85 mole percent of the residues of at least one
diacid chosen from 1,4-cyclohexanedicarboxylic acid,
1,3-cyclohexanedicarboxylic acid, hexahydrophthalic anhydride, and
combinations thereof; and about 15 to about 50 mole percent of the
residues of at least one alicyclic aliphatic diacid having from 4
to 10 carbon atoms; (b) about 50 to about 85 mole percent of the
residues of at least one diacid chosen from
1,4-cyclohexanedicarboxylic acid, hexahydrophthalic anhydride, and
combinations thereof; and about 15 to about 50 mole percent of the
residues of at least one diacid chosen from adipic acid, succinic
acid, and glutaric acid; (c) about 50 to about 75 mole percent of
the residues of at least one diacid chosen from
1,4-cyclohexanedicarboxylic acid, hexahydrophthalic anhydride, and
combinations thereof; and about 25 to about 50 mole percent of the
residues of at least one diacid chosen from adipic acid, succinic
acid, and glutaric acid; (d) about 50 to about 65 mole percent of
the residues of at least one diacid chosen from
1,4-cyclohexanedicarboxylic acid, hexahydrophthalic anhydride, and
combinations thereof; and about 35 to about 50 mole percent of the
residues of at least one diacid chosen from adipic acid, succinic
acid, and glutaric acid; (e) about 50 mole percent of the residues
of one or diacids chosen from 1,4-cyclohexanedicarboxylic acid,
hexahydrophthalic anhydride, and combinations thereof; and about 50
mole percent of the residues of adipic acid; and (f) about 50 mole
percent of the residues of 1,4-cyclohexanedicarboxylic acid and
about 50 mole percent of the residues of adipic acid. In addition
to the residues of alicyclic and cyclic aliphatic dicarboxylic
acids described above, the diacid residues may further comprise
from 0 to about 10 mole percent of the residues of at least one
aromatic dicarboxylic acid chosen from phthalic acid, terephthalic
acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, and
combinations thereof.
[0038] In addition to the aliphatic diacid residues described
above, the acid component of our inventive polyester composition
may further comprise the residues of a monocarboxylic acid or a
polybasic acid containing more that 2 carboxylic acid groups. For
example, the curable, aliphatic polyester may comprise residues of
at least one monocarboxylic acid or a polybasic acid chosen from
benzoic acid, acetic acid, 2-ethyl-hexanoic acid, propionic acid,
tert-butyl benzoic acid, and butanoic acid; trimellitic anhydride;
or a mixture thereof. In another example, the acid component can
comprise the residues of at least one aliphatic tricarboxylic acid
such as, for example, 1,2,4-cyclohexanetricarboxylic acid,
1,3,4-butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, and
mixtures of one or more of these acids.
[0039] The curable, aliphatic polyester also comprises the residues
of 2,2,4,4-tetramethyl-1,3-cyclobutanediol ("TMCD"). For example,
the curable, aliphatic polyester can comprise about 50 to 100 mole
percent TMCD, based on the total moles of diol residues. Other
representative examples of TMCD concentrations, are about 75 to 100
mole percent, and about 85 to 100 mole percent.
[0040] Other aliphatic diols, in addition to TMCD, can be used to
prepare the curable, aliphatic polyester of the instant invention.
Representative examples of aliphatic diols include, but are not
limited to, neopentyl glycol, ethylene glycol, propylene glycol,
diethylene glycol, triethylene glycol, tetraethylene glycol,
pentaethylene glycol, hexaethylene glycol, heptaethylene glycol,
octaethylene glycol, nonaethylene glycol, decaethylene glycol,
1,3-propanediol, 2,4-dimethyl-2-ethyl-hexane-1,3-diol,
2,2-dimethyl-1,2-propanediol, 2-ethyl-2-butyl-1,3-propanediol,
2-ethyl-2-isobutyl-1,3-propanediol, 1,2-butanediol, 1,3-butanediol,
1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol,
2-ethyl-1,3-hexanediol, 2,2,4,4-tetramethyl-1,6-hexanediol,
thiodiethanol, 1,2-cyclohexanedimethanol,
1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol,
2,2,4-trimethyl 1,3-pentanediol, 2,4-diethyl-1,5-pentanediol,
hydroxypivalyl hydroxypivalate, 1,10-decanediol and hydrogenated
bisphenol A. For example, in one embodiment, the curable, aliphatic
polyester resins comprise a combination of the residues of
neopentyl glycol and TMCD. It should be understood that the diols
listed above may be used in any combination with TMCD and the
aforementioned diacid components and in any amount within the
ranges described hereinabove
[0041] For example, in one embodiment, the curable, aliphatic
polyester can comprise (i) diacid residues comprising about 50 to
about 85 mole percent of the residues of at least one
cycloaliphatic dicarboxylic acid chosen from
1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid,
hexahydrophthalic anhydride, and about 15 to about 50 mole percent
of the residues at least one acylic aliphatic dicarboxylic acid
chosen from dodecanedioic acid, adipic acid, sebacic acid, azelaic
acid, maleic acid, fumaric acid, succinic acid, and glutaric acid;
and (ii) diol residues comprising about 50 to 100 mole percent of
the residues of TMCD and about 50 to 0 mole percent of the residues
of at least one diol chosen from neopentyl glycol, ethylene glycol,
propylene glycol, diethylene glycol, triethylene glycol,
tetraethylene glycol, pentaethylene glycol, hexaethylene glycol,
heptaethylene glycol, octaethylene glycol, nonaethylene glycol,
decaethylene glycol, 1,3-propanediol,
2,4-dimethyl-2-ethyl-hexane-1,3-diol, 2,2-dimethyl-1,2-propanediol,
2-ethyl-2-butyl-1,3-propanediol,
2-ethyl-2-isobutyl-1,3-propanediol, 1,3-butanediol, 1,4-butanediol,
1,5-pentanediol, 1,6-hexanediol, 2,2,4-trimethyl-1,6-hexanediol,
thiodiethanol, 1,2-cyclohexanedimethanol,
1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol,
2,2,4-trimethyl 1,3-pentanediol, p-xylenediol, hydroxypivalyl
hydroxypivalate, 1,10-decanediol, and hydrogenated bisphenol A. In
another example, the curable aliphatic polyester can comprise (i)
diacid residues comprising about 50 to about 85 mole percent of the
residues of 1,4-cyclohexanedicarboxylic acid, hexahydrophthalic
anhydride, or a mixture thereof, and about 15 to about 50 mole
percent of the residues of adipic acid; and (ii) diol residues
comprising about 50 to 100 mole percent of the residues of TMCD and
about 50 to 0 mole percent of the residues of neopentyl glycol. In
yet another example, the curable, aliphatic polyester can comprise
(i) diacid resides comprising about 50 mole percent of the residues
of hexahydrophthalic anhydride and about 50 mole percent of the
residues of adipic acid; and (ii) diol residues comprising about 75
to 100 mole percent of the residues of
2,2,4,4-tetramethyl-1,3-cyclobutanediol, and about 25 to 0 mole
percent of the residues of neopentyl glycol.
[0042] In addition to diacid and diol residues, the curable,
aliphatic polyester comprises about 2 to about 40 mole percent of
the residues of at least one polyol, based on the total moles of
diol and polyol residues. These polyols may include aliphatic,
alicyclic, and cyclic alkyl polyols. Some specific examples of
polyols include, but are not limited to, trimethylolpropane
(abbreviated herein as "TMP), pentaerythritol (abbreviated herein
as "PE"), trimethylolethane (abbreviated herein as "TME"),
erythritol, threitol, dipentaerythritol, sorbitol, glycerine, and
the like. In one example, the curable, aliphatic polyester can
comprise about 3 to about 30 mole percent of the residues of at
least one polyol selected from trimethylolpropane, pentaerythritol,
trimethylolethane, erythritol, threitol, dipentaerythritol,
sorbitol, and glycerine. In another embodiment, the curable,
aliphatic polyester comprises trimethylolpropane.
[0043] The curable, aliphatic polyester of this invention has a
hydroxyl number of about 20 to about 450 mg KOH/g resin. Further
examples of hydroxyl number are about 25 to about 300, and about 30
to about 250. In addition, the curable, aliphatic polyester has an
acid number of about 0 to about 80 mg KOH/g polyester or, in other
examples, about 2 to about 25 mg KOH/g polyester, and about 2 to
about 15 mg KOH/g polyester. The number average molecular weight of
the curable, aliphatic polyester is about 300 daltons to about
10,000 daltons. Additional examples of molecular weight ranges are
about 400 to about 7000, and about 500 to about 5000. The curable,
aliphatic polyester has a glass transition temperature (abbreviated
herein as "Tg") of about -35 to about 35.degree. C. Some
additional, representative examples of Tg ranges for the curable,
aliphatic polyester are about -35 to about 30.degree. C., about -35
to about 25.degree. C., about -35 to less than 20, about -35 to
about 19.degree. C., about -35 to about 18.degree. C., about -35 to
about 17.degree. C., about -35 to about 16.degree. C., about -35 to
about 15.degree. C., about -35 to about 10.degree. C. For example,
the curable, aliphatic polyester can have a hydroxyl number of
about 30 to about 250 mg potassium hydroxide per gram of polyester,
an acid number of about 2 to about 15 mg potassium hydroxide per
gram of polyester, and a number average molecular weight of about
700 to about 7000 daltons, and a Tg of about -20 to about
20.degree. C.
[0044] A further aspect of the invention is a curable, aliphatic
polyester, consisting essentially of: [0045] i. diacid residues,
consisting essentially of the residues of at least one aliphatic
diacid, the aliphatic dicarboxylic acid comprising about 50 to 100
mole percent, based on the total moles of diacid residues, of a
cycloaliphatic dicarboxylic acid selected from residues of
1,4-cyclohexanedicarboxylic acid, hexahydrophthalic anhydride, or a
mixture thereof; [0046] ii. diol residues, consisting essentially
of about 75 to 100 mole percent, based on the total moles of diol
residues, of the residues of
2,2,4,4-tetramethyl-1,3-cyclobutanediol; [0047] iii. about 2 to
about 40 mole percent of the residues of at least one polyol, based
on the total moles of diol and polyol residues; wherein the
curable, aliphatic polyester has a number average molecular weight
of about 300 to about 10,000 daltons, a glass transition
temperature of about -35.degree. C. to about 35.degree. C., a
hydroxyl number of about 20 to about 450 mg KOH/g of polyester, and
an acid number of 0 to about 80 mg KOH/g of polyester.
[0048] The phrase "consisting essentially of", as used herein is
intended to encompass curable polyesters having components
(i)-(iii) listed above and is understood to exclude any elements
that would substantially alter the essential properties of the
polyester to which the phrase refers. For example, the diacid and
diol residues may include other components that do not alter the
solubility of the curable, aliphatic polyester and its
compatibility with TSA resins. For example, any combination of
diol, diacid, and polyol monomers that would produce a resin having
a Tg greater than about 45.degree. C. would be understood in the
art to reduce that solubility of a polyester polymer would be
excluded from this embodiment. Some representative classes of
diacids and diols that would be expected to increase Tg and reduce
solubility include, but are not limited to, cycloaliphatic diol or
diacid components, and polycycloaliphatic diacids or diols. Some
examples of diacid and diol components that would be excluded from
this embodiment are hydrogenated bisphenol A at 50 mole percent or
greater and tetrahydrophthalic acid or anhydride at 25 mole percent
or greater. All mole percentages are based upon the total moles of
diacid or diol residues.
[0049] By contrast, some examples of compositions that would be
included in the above embodiment are those, for example, in which
the aliphatic polyester consists essentially of (i) diacid residues
consisting essentially of about 50 to about 85 mole percent of the
residues of at least one cycloaliphatic dicarboxylic acid chosen
from 1,4-cyclohexanedicarboxylic acid, hexahydrophthalic anhydride,
and about 50 to about 15 mole percent of the residues at least one
acyclic aliphatic dicarboxylic acid chosen from adipic acid,
dodecanedioic acid, sebacic acid, azelaic acid, maleic acid,
fumaric acid, succinic acid, and glutaric acid; and (ii) diol
residues consisting essentially of about 75 to 100 mole percent of
the residues of 2,2,4,4-tetramethyl-1,3-cyclobutanediol and about
25 to 0 mole percent of the residues of at least one diol chosen
from neopentyl glycol, ethylene glycol, propylene glycol,
diethylene glycol, triethylene glycol, tetraethylene glycol,
pentaethylene glycol, hexaethylene glycol, heptaethylene glycol,
octaethylene glycol, nonaethylene glycol, decaethylene glycol,
1,3-propanediol, 2,4-dimethyl-2-ethyl-hexane-1,3-diol,
2,2-dimethyl-1,2-propanediol, 2-ethyl-2-butyl-1,3-propanediol,
2-ethyl-2-isobutyl-1,3-propanediol, 1,3-butanediol, 1,4-butanediol,
1,5-pentanediol, 1,6-hexanediol, 2,2,4-trimethyl-1,6-hexanediol,
thiodiethanol, 1,2-cyclohexanedimethanol,
1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol,
2,2,4-trimethyl 1,3-pentanediol, hydroxypivalyl hydroxypivalate,
1,10-decanediol, and hydrogenated bisphenol A. In another example,
the curable aliphatic polyester consists essentially of (i) diacid
residues consisting essentially of about 50 to about 85 mole
percent of the residues of 1,4-cyclohexanedicarboxylic acid,
hexahydrophthalic anhydride, or a mixture thereof, and about 15 to
about 50 mole percent of the residues of adipic acid; and (ii) diol
residues consisting essentially of about 75 to 100 mole percent of
the residues of TMCD and about 25 to 0 mole percent of the residues
of neopentyl glycol. In yet another example, the curable, aliphatic
polyester can consist essentially of (i) diacid resides consisting
essentially of about 50 mole percent of the residues of
hexahydrophthalic anhydride and about 50 mole percent of the
residues of adipic acid; and (ii) diol residues consisting
essentially of about 75 to 100 mole percent of the residues of
2,2,4,4-tetramethyl-1,3-cyclobutanediol, and about 25 to 0 mole
percent of the residues of neopentyl glycol.
[0050] The curable, aliphatic polyester has a glass transition
temperature (abbreviated herein as "Tg") of about -35 to about
35.degree. C. Some additional, representative examples of Tg ranges
for the curable, aliphatic polyester are about -35 to about
30.degree. C., about -35 to about 25.degree. C., about -35 to less
than 20, about -35 to about 19.degree. C., about -35 to about
18.degree. C., about -35 to about 17.degree. C., about -35 to about
16.degree. C., about -35 to about 15.degree. C., about -35 to about
10.degree. C.
[0051] The curable, aliphatic polyester can be prepared by heating
the reactants until the desired molecular weight, acid number, or
hydroxyl number is reached. The reaction can be monitored by the
collection of water (when diacids are used as starting materials)
or alcohol (when diesters are used). The polyester typically can be
prepared at a temperature range of about 150 to about 250.degree.
C. and at atmospheric pressure or under vacuum. In one embodiment,
for example, the diacid and diol components of the polyester may be
partially reacted before the polyol is added. Once the polyol is
added to the reaction mixture, heating is continued until a target
acid number is satisfied.
[0052] Alternatively, the curable, aliphatic polyester can be
prepared in the presence of a process solvent to help remove the
water or alcohol by-products of the reaction and to promote the
synthesis of the polyester resin. The process solvent may be any
solvent known in the art as useful for the preparation of polyester
polymers. For example, the process solvent can be a hydrocarbon
solvent. In another example, the process solvent can comprise an
aromatic hydrocarbon such as, for example, xylene. The xylene can
be a pure isomer, or a mixture of ortho, meta, and para isomers.
The amount of process solvent may be determined by routine
experimentation as understood by those skilled in the art. The
process solvent can be added in amounts ranging from 0.5 to about 5
weight percent, based on the total weight of reaction mixture.
[0053] Optionally, a catalyst may be used to promote the synthesis
of the polyester. The catalyst may be any catalyst known in the art
to be useful for the formation of polyester resins. For example,
the catalyst can be a tin catalyst, such as, for example,
FASCAT.TM. 4100 (available from Arkema Corporation). The catalyst
increases the rate of the polyester resin reaction, as described
above, and its amount may be determined by routine experimentation
as understood by those skilled in the art. Ordinarily, the catalyst
is added in amounts ranging from about 0.01 to about 1.00 weight
percent based on the total weight of the reactants.
[0054] Our invention also provides a coating composition comprising
the various embodiments of the curable, aliphatic polyester resin
containing 2,2,4,4-tetramethyl-1,3-cyclobutanediol (TMCD) as
described above. Thus, another aspect of the present invention is a
thermosetting coating composition, comprising: [0055] (A). about 50
to about 90 weight percent, based on the total weight of (A) and
(B) of at least one curable, aliphatic polyester, comprising [0056]
i. diacid residues, comprising at least 90 mole percent, based on
the total moles of diacid residues, of the residues of at least one
aliphatic diacid, the aliphatic dicarboxylic acid comprising about
50 to 100 mole percent of a cycloaliphatic dicarboxylic acid;
[0057] ii. diol residues, comprising about 50 to 100 mole percent,
based on the total moles of diol residues, of the residues of
2,2,4,4-tetramethyl-1,3-cyclobutanediol; and [0058] iii. about 2 to
about 40 mole percent of the residues of at least one polyol, based
on the total moles of diol and polyol residues; [0059] wherein the
curable, aliphatic polyester has a number average molecular weight
of about 300 to about 10,000 daltons, a glass transition
temperature of about -35.degree. C. to about 35.degree. C., a
hydroxyl number of about 20 to about 450 mg KOH/g of polyester, and
an acid number of 0 to about 80 mg KOH/g of polyester; [0060] (B).
about 10 to about 50 weight percent, based on the total weight of
(A) and (B) of a crosslinker comprising at least one compound
reactive with a carboxylic acid or a hydroxyl group; [0061] (C).
about 10 to about 60 weight percent, based on the total weight of
(A), (B), and (C) of at least one nonaqueous solvent.
[0062] It is understood that the curable, aliphatic polyester
component of coating composition may include any combination of the
various embodiments of diacids, diols, polyols, acid and hydroxyl
numbers, and glass transition temperatures described hereinabove in
accordance with the present invention. For example, the curable,
aliphatic polyester can comprise about 50 mole percent of the
residues of 1,4-cyclohexanedicarboxylic acid and about 50 mole
percent of the residues of adipic acid, based on the total moles of
diacid residues. In another example, the curable, aliphatic
polyester can contain about 50 mole percent of the residues of
hexahydrophthalic anhydride and about 50 mole percent of the
residues of adipic acid. Some additional, non-limiting examples of
the diacid component of curable, aliphatic polyester are as
follows: (a) about 50 to about 85 mole percent of the residues of
at least one diacid chosen from 1,4-cyclohexanedicarboxylic acid,
1,3-cyclohexanedicarboxylic acid, hexahydrophthalic anhydride, and
combinations thereof; and about 15 to about 50 mole percent of the
residues of at least one alicyclic aliphatic diacid having from 4
to 10 carbon atoms; (b) about 50 to about 85 mole percent of the
residues of at least one diacid chosen from
1,4-cyclohexanedicarboxylic acid, hexahydrophthalic anhydride, and
combinations thereof; and about 15 to about 50 mole percent of the
residues of at least one diacid chosen from adipic acid, succinic
acid, and glutaric acid; (c) about 50 to about 75 mole percent of
the residues of one or diacids chosen from
1,4-cyclohexanedicarboxylic acid, hexahydrophthalic anhydride, and
combinations thereof; and about 25 to about 50 mole percent of the
residues of at least one diacid chosen from adipic acid, succinic
acid, and glutaric acid; (d) about 50 to about 65 mole percent of
the residues of one or diacids chosen from
1,4-cyclohexanedicarboxylic acid, hexahydrophthalic anhydride, and
combinations thereof; and about 35 to about 50 mole percent of the
residues of at least one diacid chosen from adipic acid, succinic
acid, and glutaric acid; (e) about 50 mole percent of the residues
of one or diacids chosen from 1,4-cyclohexanedicarboxylic acid,
hexahydrophthalic anhydride, and combinations thereof; and about 50
mole percent of the residues of adipic acid; and (f) about 50 mole
percent of the residues of 1,4-cyclohexanedicarboxylic acid and
about 50 mole percent of the residues of adipic acid. In addition
to the residues of alicyclic and cyclic aliphatic dicarboxylic
acids described above, the diacid residues may further comprise
from 0 to about 10 mole percent of the residues of at least one
aromatic dicarboxylic acid chosen from phthalic acid, terephthalic
acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, and
combinations thereof.
[0063] As described previously, the acid component of our inventive
polyester composition may further comprise the residues of a
monocarboxylic acid or a polybasic acid containing more that 2
carboxylic acid groups, such as, for example, the residues of at
least one monobasic or polybasic carboxylic acid chosen from
benzoic acid, acetic acid, 2-ethylhexanoic acid, propionic acid,
tert-butyl benzoic acid, butanoic acid; trimellitic acid;
1,2,4-cyclohexanetricarboxylic acid, 1,3,4-butanetricarboxylic
acid, and 1,2,5-hexanetricarboxylic acid.
[0064] In addition to TMCD, the curable, aliphatic polyester of the
coating composition can comprise from 0 to about 50 mole percent of
at least one aliphatic diol. Representative examples of aliphatic
diols include, but are not limited to, neopentyl glycol, ethylene
glycol, propylene glycol, diethylene glycol, triethylene glycol,
tetraethylene glycol, pentaethylene glycol, hexaethylene glycol,
heptaethylene glycol, octaethylene glycol, nonaethylene glycol,
decaethylene glycol, 1,3-propanediol,
2,4-dimethyl-2-ethyl-hexane-1,3-diol, 2,2-dimethyl-1,2-propanediol,
2-ethyl-2-butyl-1,3-propanediol,
2-ethyl-2-isobutyl-1,3-propanediol, 1,2-butanediol, 1,3-butanediol,
1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol,
2-ethyl-1,3-hexanediol, 2,2,4,4-tetramethyl-1,6-hexanediol,
thiodiethanol, 1,2-cyclohexanedimethanol,
1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol,
2,2,4-trimethyl 1,3-pentanediol, 2,4-diethyl-1,5-pentanediol,
hydroxypivalyl hydroxypivalate, 1,10-decanediol and hydrogenated
bisphenol A. For example, in one embodiment, the curable, aliphatic
polyester resins comprise a combination of the residues or
neopentyl glycol and TMCD. It should be understood that the diols
listed above may be used in any combination with TMCD and the
diacid components and in any amount within the ranges described
hereinabove.
[0065] For example, in one embodiment, the curable, aliphatic
polyester can comprise (i) diacid residues comprising about 50 to
about 85 mole percent of the residues of at least one
cycloaliphatic dicarboxylic acid chosen from
1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid,
hexahydrophthalic anhydride, and about 15 to about 50 mole percent
of the residues at least one acylic aliphatic dicarboxylic acid
chosen from adipic acid, dodecanedioic acid, sebacic acid, azelaic
acid, maleic acid, fumaric acid, succinic acid, and glutaric acid;
and (ii) diol residues comprising about 50 to 100 mole percent of
the residues of TMCD and about 50 to 0 mole percent of the residues
of at least one diol chosen from neopentyl glycol, ethylene glycol,
propylene glycol, diethylene glycol, triethylene glycol,
tetraethylene glycol, pentaethylene glycol, hexaethylene glycol,
heptaethylene glycol, octaethylene glycol, nonaethylene glycol,
decaethylene glycol, 1,3-propanediol,
2,4-dimethyl-2-ethyl-hexane-1,3-diol, 2,2-dimethyl-1,2-propanediol,
2-ethyl-2-butyl-1,3-propanediol,
2-ethyl-2-isobutyl-1,3-propanediol, 1,3-butanediol, 1,4-butanediol,
1,5-pentanediol, 1,6-hexanediol, 2,2,4-trimethyl-1,6-hexanediol,
thiodiethanol, 1,2-cyclohexanedimethanol,
1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol,
2,2,4-trimethyl 1,3-pentanediol, p-xylenediol, hydroxypivalyl
hydroxypivalate, 1,10-decanediol, and hydrogenated bisphenol A. In
another example, the curable aliphatic polyester can comprise (i)
diacid residues comprising about 50 to about 85 mole percent of the
residues of 1,4-cyclohexanedicarboxylic acid, hexahydrophthalic
anhydride, or a mixture thereof, and about 15 to about 50 mole
percent of the residues of adipic acid; and (ii) diol residues
comprising about 50 to 100 mole percent of the residues of TMCD and
about 50 to 0 mole percent of the residues of neopentyl glycol. In
yet another example, the curable, aliphatic polyester can comprise
(i) diacid resides comprising about 50 mole percent of the residues
of hexahydrophthalic anhydride and about 50 mole percent of the
residues of adipic acid; and (ii) diol residues comprising about 75
to 100 mole percent of the residues of
2,2,4,4-tetramethyl-1,3-cyclobutanediol, and about 25 to 0 mole
percent of the residues of neopentyl glycol.
[0066] In addition to diacid and diol residues, the curable,
aliphatic polyester of the coating composition comprises about 2 to
about 40 mole percent of the residues of at least one polyol, based
on the total moles of diol and polyol residues. These polyols may
include aliphatic, alicyclic, and cyclic alkyl polyols. Some
specific examples of polyols include, but are not limited to,
trimethylolpropane (abbreviated herein as "TMP), pentaerythritol
(abbreviated herein as "PE"), trimethylolethane (abbreviated herein
as "TME"), erythritol, threitol, dipentaerythritol, sorbitol,
glycerine, and the like. In one example, the curable, aliphatic
polyester can comprise about 3 to about 30 mole percent of the
residues of at least one polyol selected from trimethylolpropane,
pentaerythritol, trimethylolethane, erythritol, threitol,
dipentaerythritol, sorbitol, and glycerine. In another embodiment,
the curable, aliphatic polyester comprises trimethylolpropane.
[0067] The curable, aliphatic polyester of this invention has a
hydroxyl number of about 20 to about 450 mg KOH/g resin. Further
examples of hydroxyl number are about 25 to about 300, and about 30
to about 250. In addition, the curable, aliphatic polyester has an
acid number of about 0 to about 80 mg KOH/g polyester or, in other
examples, about 2 to about 25 mg KOH/g polyester, and about 2 to
about 15 mg KOH/g polyester. The number average molecular weight of
the curable, aliphatic polyester is about 300 daltons to 10000
daltons. Additional examples of molecular weight ranges are about
400 to about 7000, and about 500 to about 5000. The curable,
aliphatic polyester has a glass transition temperature (abbreviated
herein as "Tg") of about -35 to about 35.degree. C. Some
additional, representative examples of Tg ranges for the curable,
aliphatic polyester are about -35 to about 30.degree. C., about -35
to about 25.degree. C., about -35 to less than 20, about -35 to
about 19.degree. C., about -35 to about 18.degree. C., about -35 to
about 17.degree. C., about -35 to about 16.degree. C., about -35 to
about 15.degree. C., about -35 to about 10.degree. C. For example,
the curable, aliphatic polyester can have a hydroxyl number of
about 30 to about 250 mg potassium hydroxide per gram of polyester,
an acid number of about 2 to about 15 mg potassium hydroxide per
gram of polyester, and a number average molecular weight of about
700 to about 7000 daltons, and a Tg of about -20 to about
20.degree. C.
[0068] The curable, aliphatic polyester resin comprises a reactive
functional group, typically a hydroxyl group or carboxyl group for
the purpose of later reacting with a crosslinker in a coating
formulation. The functional group is controlled by having either
excess diol or acid (from dicarboxylic acid or tricarboxylic acid)
in the polyester resin composition. The desired crosslinking
pathway will determine whether the polyester resin will be
hydroxyl-terminated or carboxylic acid-terminated. The concept is
known to those skilled in the art and described in Organic Coatings
Science and Technology, 2nd ed., p. 246-257, by Z. Wicks, F. Jones,
and S. Pappas, Wiley, New York, 1999.
[0069] The thermosetting coating composition may further contain
about 10 to about 50 weight percent of at least one crosslinker,
based on the combined weight of the polyester and the crosslinker.
Typically, the crosslinker will be a compound, generally known in
the art, that can react with either the carboxylic acid-terminated
or hydroxyl-terminated polyester resin. For example, the
crosslinker can comprise at least one compound chosen from
epoxides, melamines, hydroxy alkyl amides, and isocyanates. For
example, epoxide crosslinkers will react with a carboxylic
acid-terminated polyester resin, whereas melamines, isocyanates,
and isocyanurates will react with a hydroxyl-terminated
polyesters.
[0070] Melamine or "amino" crosslinkers also are well-known in the
art and can be used in the coating composition of the invention.
For example, the coating composition of the present invention can
comprise at least one melamine compound chosen from
hexamethoxymethylmelamine, tetramethoxymethylbenzoguanamine,
tetramethoxy-methylurea, and mixed butoxy/methoxy substituted
melamines. Some examples of commercially available melamine
crosslinkers include the CYMEL.TM. 300 series and CYMEL.TM. 1100
series melamine crosslinkers, available from Cytec Surface
Specialties. The polyester to melamine weight ratio is typically
about 50:50 to about 90:10. Other examples of polyester:melamine
weight ratios are about 60:40 to about 85:15 and about 65:35 to
about 80:20.
[0071] In addition to melamines, isocyanates and isocyanurates can
be used as crosslinkers in accordance with the invention.
Representative isocyanates and isocyanurates include, but are not
limited to, toluene diisocyanate, isocyanurates of toluene
diisocyanate, diphenylmethane 4,4'-diisocyanate, isocyanurates of
4,4'-diisocyanate, methylenebis-4,4'-isocyanatocyclohexane,
isophorone diisocyanate, isocyanurates of isophorone diisocyanate,
the biuret of 1,6-hexamethylene diisocyanate, 1,6-hexamethylene
diisocyanate, isocyanurates of 1,6-hexamethylene diisocyanate,
1,4-cyclohexane diisocyanate, p-phenylene diisocyanate, and
triphenylmethane 4,4',4''-triisocyanate, tetramethyl xylene
diisocyanate, metaxylene diisocyanate, polyisocyanates,
1,4-butylene diisocyanate, methylene bis(4-cyclohexyl isocyanate),
isophorone diisocyanate and isocyanate-terminated adducts of
ethylene glycol, 1,4-butylene glycol, trimethylol propane, or
combinations thereof.
[0072] The coating composition also can comprise
isocyanate-terminated adducts of diols and polyols, such as
ethylene glycol, 1,4-butylene glycol, trimethylol propane, etc., as
crosslinkers. These crosslinkers are formed by reacting more than
one equivalent of a diisocyanate, such as those mentioned above,
with one equivalent of a diol or polyol to form a higher molecular
weight isocyanate prepolymer with a isocyanate functionality of 2
to 3. Some commercial examples of isocyanate-terminated adducts
include isocyanate crosslinkers under the DESMODUR.TM. and
MONDUR.TM. trademarks available from Bayer Material Science and
under the TOLONATE.TM. trademark from Perstorp Corporation.
[0073] In one embodiment of the invention, the crosslinker
comprises at least one aliphatic isocyanate, which can provide good
outdoor durability and color stability in the cured coating.
Examples of aliphatic isocyanates include 1,6-hexamethylene
diisocyanate, 1,4-butylene diisocyanate, methylene bis(4-cyclohexyl
isocyanate), isophorone diisocyanate, and combinations thereof.
Mixtures of isocyanate crosslinkers can also be employed. In yet
another embodiment, the crosslinker can comprise isocyanurates of
1,6-hexamethylene diisocyanate, the biuret of 1,6-hexamethylene
diisocyanate, or a mixture thereof.
[0074] Stoichiometric calculations for the curable, aliphatic
polyester and isocyanate reaction are known to those skilled in the
art and are described in The Chemistry of Polyurethane Coatings,
Technical Publication, p. 20, by Bayer Material Science, 2005.
Persons having ordinary skill in the art will understand that
crosslinking between the polyester resin and isocyanate reaches
maximum molecular weight and optimal properties associated with
molecular weight at an isocyanate:hydroxyl equivalent ratio of
about 1:1; that is, when one equivalent of isocyanate (--NCO)
reacts with one equivalent of hydroxyl (--OH). Typically, however,
a small excess of isocyanate, for example, about 5 to about 10%
above a 1:1 equivalent, is used to allow for the loss of isocyanate
by the reaction with adventitious moisture from the atmosphere,
solvents, and pigments. Other NCO:OH ratios can be used; for
example, it may be desirable to vary the NCO to OH ratio to less
than 1:1 to improve flexibility or greater than 1:1 to produce
harder, more chemical resistant, and more weather resistant
coatings.
[0075] For the present invention, the solvent borne, thermosetting
coating composition has an NCO:OH ratio, on an equivalent basis, of
about 0.9:1.0 to about 1.5:1.0. Examples of other NCO:OH ratios are
about 0.95:1.0 to about 1.25:1.0 and about 0.95:1.0 to about
1.1:1.0.
[0076] The thermosetting coating composition also comprises about
10 to about 60 weight percent, based on the total weight of
components (A), (B), and (C) of a solvent. Examples of solvents
include, but are not limited to, benzene, xylene, mineral spirits,
naptha, toluene, acetone, methyl ethyl ketone, methyl n-amyl
ketone, methyl isoamyl ketone, n-butyl acetate, isobutyl acetate,
t-butyl acetate, n-propyl acetate, isopropyl acetate, ethyl
acetate, methyl acetate, ethanol, n-propanol, isopropanol,
n-butanol, sec-butanol, isobutanol, ethylene glycol monobutyl
ether, propylene glycol n-butyl ether, propylene glycol methyl
ether, propylene glycol monopropyl ether, dipropylene glycol methyl
ether, diethylene glycol monobutyl ether, trimethylpentanediol
mono-isobutyrate, ethylene glycol mono-octyl ether, diacetone
alcohol, 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate (available
commercially from Eastman Chemical Co. under the trademark
TEXANOL.TM.), or combinations thereof. The coating composition may
also comprise reactive solvents such as, for example, diallyl
phthalate, SANTOLINK.TM. XI-100 polyglycidyl allyl ether (available
from Cytec), and others as described, for example, in U.S. Pat.
Nos. 5,349,026 and 5,371,148.
[0077] The coating composition, optionally, can further comprise at
least one crosslinking catalyst. Representative crosslinking
catalysts include carboxylic acids, sulfonic acids, tertiary
amines, tertiary phosphines, tin compounds, or combinations of
these compounds. Some specific examples of crosslinking catalysts
are at least one compound chosen from p-toluenesulfonic acid,
dodecylbenzene sulfonic acid, dinonylnaphthalene sulfonic acid, and
dinonylnaphthalene disulfonic acid, benzoic acid,
triphenylphosphine, dibutyltindilaurate, and dibutyltindiacetate.
The selection of a crosslinking catalyst typically depends on the
type of crosslinker that is used in the coating composition. For
example, the crosslinker can comprise a melamine or "amino"
crosslinker and the crosslinking catalyst can comprise
p-toluenesulfonic acid, unblocked and blocked dodecylbenzene
sulfonic (abbreviated herein as "DDBSA"), dinonylnaphthalene
sulfonic acid (abbreviated herein as "DNNSA") and
dinonylnaphthalene disulfonic acid (abbreviated herein as
"DNNDSA"). Some of these catalysts are available commercially under
the trademarks such as, for example, NACURE.TM. 155, 5076, 1051,
and 5225 (available from King Industries), BYK-CATALYSTS.TM.
(available from BYK-Chemie USA), and CYCAT.TM. catalysts (available
from Cytec Surface Specialties).
[0078] In another embodiment, the curable, aliphatic polyester can
comprise hydroxyl-terminated end groups and the crosslinker can
comprise an isocyanate. The coating composition also can comprise
at least one isocyanate crosslinking catalyst such as, for example,
FASCAT.TM. 4202 (dibutyltindilaurate), FASCAT.TM. 4200
(dibutyltindiacetate, both available from Arkema), DABCO.TM. T-12
(available from Air Products) and K-KAT.TM. 348, 4205, 5218,
XC-6212.TM. non-tin catalysts (available from King Industries), and
tertiary amines.
[0079] In another example, the thermosetting coating composition
can comprise about 25 to about 35 weight percent solvent, about 20
to about 35 weight percent of a melamine crosslinker, and a
crosslinking catalyst comprising p-toluenesulfonic acid. In another
example, the thermosetting coating composition comprises about 25
to about 35 weight percent solvent and about 20 to about 35 weight
percent hexamethoxy-1-methylmelamine.
[0080] The coating composition of the instant invention may further
contain at least one coating additive known in the art. Examples of
coating additives include, but are not limited to, leveling,
rheology and flow control agents such as silicones, fluorocarbons
or cellulosics; extenders; plasticizers; flatting agents; pigment
wetting and dispersing agents; ultraviolet (UV) absorbers; UV light
stabilizers; defoaming and antifoaming agents; anti-settling,
anti-sag and bodying agents; anti-skinning agents; anti-flooding
and anti-floating agents; and corrosion inhibitors. Specific
examples of such additives can be found in the Raw Material Index
and Buyer's Guide, published by the National Paint & Coatings
Association, 1500 Rhode Island Avenue, N.W., Washington., DC 20005.
Further examples of such additives may be found in U.S. Pat. No.
5,371,148.
[0081] Examples of flatting agents include, but are not limited to,
synthetic silica, available from the Davison Chemical Division of
W. R. Grace & Company as SYLOID.TM.; polypropylene, available
from Hercules Inc., as HERCOFLAT.TM.; and synthetic silicate,
available from J. M. Huber Corporation, as ZEOLEX.TM.. Examples of
dispersing agents include, but are not limited to, sodium
bis(tridecyl) sulfosuccinate, di(2-ethyl hexyl) sodium
sulfosuccinate, sodium dihexylsulfosuccinate, sodium dicyclohexyl
sulfosuccinate, diamyl sodium sulfosuccinate, sodium dusobutyl
sulfosuccinate, disodium isodecyl sulfosuccinate, disodium
ethoxylated alcohol half ester of sulfosuccinic acid, disodium
alkyl amido polyethoxy sulfosuccinate, tetra-sodium
N-(1,2-dicarboxyethyl)-N-octadecyl sulfosuccinamate, disodium
N-octasulfosuccinamate, sulfated ethoxylated nonylphenol,
2-amino-2-methyl-1-propanol, and the like.
[0082] Examples of viscosity, suspension, and flow control agents
include, but are not limited to, polyaminoamide phosphate, high
molecular weight carboxylic acid salts of polyamine amides, and
alkylene amine salts of an unsaturated fatty acid, all available
from BYK Chemie USA as ANTI TERRA.TM.. Further examples include,
but are not limited to, polysiloxane copolymers, polyacrylate
solution, cellulose esters, hydroxyethyl cellulose, hydroxypropyl
cellulose, polyamide wax, polyolefin wax, hydroxypropyl methyl
cellulose, polyethylene oxide, and the like.
[0083] Several proprietary antifoaming agents are commercially
available and include, but are not limited to, BUBREAK.TM.,
available from Buckman Laboratories Inc., BYK.TM., available from
BYK Chemie, U.S.A., FOAMASTER.TM. and NOPCO.TM., available from
Henkel Corp./Coating Chemicals, DREWPLUS.TM., available from the
Drew Industrial Division of Ashland Chemical Company, TROYSOL.TM.
and TROYKYD.TM., available from Troy Chemical Corporation, and
SAG.TM., available from Union Carbide Corporation.
[0084] Examples of UV absorbers, UV light stabilizers, and
antioxidants include, but are not limited to, substituted
benzophenone, substituted benzotriazoles, hindered amines, hindered
benzoates, phenols, and phosphites, some of which are available
from Cytec Specialty Chemicals as CYASORB.RTM. UV, and from Ciba
Specialty Chemicals as TINUVIN.RTM., CHIMASSORB.RTM., IRGANOX.RTM.
and IRGAFOS.RTM.; diethyl-3-acetyl-4-hydroxy-benzyl-phosphonate,
4-dodecyloxy-2-hydroxy benzophenone, and resorcinol monobenzoate.
For example, in one embodiment, the thermosetting coating
composition can contain IRGANOX.RTM. 1010 antioxidant, available
from Ciba Specialty Chemicals.
[0085] Such paint or coating additives as described above form a
relatively minor proportion of the coating composition, generally
about 0.05 weight percent to about 5.00 weight percent. For
example, a coating composition optionally may contain at least one
of the above-described additives and at least one pigment.
[0086] The solvent borne thermosetting coating composition, as
described above, also may comprise at least one pigment. Typically,
the pigment is present in an amount of about 20 to about 60 weight
percent, based on the total weight of the composition. Examples of
pigments include those generally recognized by persons of ordinary
skill in the art of surface coatings. For example, the pigment may
be a typical organic or inorganic pigment, especially those set
forth by the Colour Index, 3rd ed., 2nd Rev., 1982, published by
the Society of Dyers and Colourists in association with the
American Association of Textile Chemists and Colorists. Other
examples of suitable pigments include, but are not limited to,
titanium dioxide, barytes, clay, calcium carbonate, CI Pigment
White 6 (titanium dioxide), CI Pigment Red 101 (red iron oxide), CI
Pigment Yellow 42, CI Pigment Blue 15, 15:1,15:2, 15:3,15:4 (copper
phthalocyanines); CI Pigment Red 49:1 and CI Pigment Red 57:1.
Colorants such as, for example, phthalocyanine blue, molybdate
orange, or carbon black also may be added to the coating
composition. For example, the solvent borne, thermosetting coating
formulations can contain titanium dioxide as the pigment.
[0087] The thermosetting coating composition of this invention may
optionally comprise a TSA resin. Thermosetting acrylic ("TSA")
resins are prepared by free radical polymerization in bulk or in a
solvent. Initiators are of the free radical type and are usually
organic peroxides or azo compounds, such as benzoyl peroxide,
t-butyl hydroperoxide, t-butyl peroxide, t-butyl peroxybenzoate,
azobisisobutyronitrile, and
2,2'-azobis(2,4-dimethyl)-valeronitrile. The reaction is preferably
carried out at the reflux temperature of the solvent used, which is
generally higher than the thermal decomposition temperature of the
initiator employed. The acrylic resin is composed of ethylenically
unsaturated monomers that include acrylate, methacrylate, styrene,
(meth) acrylic acid, and vinyl esters. They further contain
hydroxyl, epoxy, carboxyl, blocked-phenol and/or acetoacetoxy
functional groups. Suitable examples of preparation methods and
components of the acrylic resin include those known in the art
including, but not limited to, those described above, and in Resins
for Surface Coatings, Vol. II, p. 121-210, ed. by P. K. T. Oldring
and G. Hayward, SITA Technology, London, UK, 1987.
[0088] Examples of hydroxyl functional TSA resins include the
MACRYNAL.TM. series, available from Cytec Surface Specialties; the
ACRYLOID.TM. series, available from Rohm and Haas; and the
JONCRYL.TM. series, available from BASF Corporation. One specific
example of a hydroxyl functional TSA resin used is MACRYNAL.TM. SM
515/70BAC, available from Cytec Surface Specialties.
[0089] The curable, aliphatic polyester and the TSA resin can be
blended together. The weight percent of polyester in the blend is
about 5 to about 50 wt. percent preferably about 10 to about 40
weight percent, and most preferably about 15 to about 30 weight
percent.
[0090] Typically, the thermosetting coating composition and
additives can be formulated into coating that contains about 40 to
about 90% non-volatiles. After formulation, the coating composition
can be applied to a substrate or article. Thus, a further aspect of
the present invention is a shaped or formed article that has been
coated with the coating compositions of the present invention. The
substrate can be any common substrate such as paper; polymer films
such as polyethylene or polypropylene; wood; metals such as
aluminum, steel or galvanized sheeting; glass; urethane elastomers;
primed (painted) substrates; and the like. The coating composition
can be coated onto a substrate using techniques known in the art,
for example, by spraying, draw-down, roll-coating, etc., about 0.5
to about 4 mils of wet coating onto a substrate. The coating can be
cured at ambient (room) temperature or heated in a forced air oven
to a temperature of about 50.degree. C. to about 175.degree. C.,
for a time period that typically ranges about 5 to about 90 minutes
and allowed to cool. Further examples of typical application and
curing methods can be found in U.S. Pat. Nos. 4,737,551 and
4,698,391 and 3,345,313. The invention is further illustrated by
the following examples.
EXAMPLES
Preparation of Curable, Aliphatic Polyesters
Comparative Example P1, Example P2, Example P3 and Example P4
[0091] The example and comparative aliphatic polyester resins
(Table 1) were prepared according to the following procedure,
targeting a number average molecular weight=1250, a hydroxyl
equivalent weight=500, a hydroxyl functionality=2.5 and final acid
number=8.
[0092] The resins were prepared using a solvent process to help
remove the water of esterification. The resins were prepared in a
two-liter reaction kettle equipped with a heating mantle,
mechanical stirrer, thermocouple, nitrogen blanket (0.6 scfh),
oil-heated partial condenser (103.degree. C.-105.degree. C.),
condensate trap, and water-cooled total condenser (15.degree. C.).
The condensate trap, kettle top and adapter from the kettle to the
column were insulated by aluminum foil and fiberglass tape to
facilitate water removal. Stage 1 raw materials were charged to the
reactor. Additional xylene (approximately 30 g) was used to fill
the condensate trap. The temperature was then increased from room
temperature to 150.degree. C. over ninety minutes to form a
homogenous melt. Agitation (300 rpm) was started and the
temperature increased to a maximum of 230.degree. C. over 240
minutes. The Stage 2 TMP was added when half the theoretical
condensate was collected. The reaction mixture was held at
230.degree. C. until a final acid number of 6.+-.2 mg KOH/g resin
was obtained. The resins were then poured into a metal paint
can.
[0093] The acid number (abbreviated "AN"), hydroxyl number
(abbreviated "OH#"), number average molecular weight (abbreviated
"Mn") and glass transition temperature (abbreviated "Tg") of the
polyesters are shown in Table 1. Acid number was determined using
ASTM method D 1639. Hydroxyl number was determined by esterifying
the resin by reaction with excess acetic anhydride in pyridine and
then decomposing the unreacted anhydride with water. The resulting
acetic acid is then titrated with a standard solution of KOH. The
number of milligrams KOH which are equivalent to one gram of resin
sample is reported as the hydroxyl number. Number average molecular
weight was determined by gel permeation chromatography using a
refractive index detector with polystyrene standards.
[0094] Residual xylene remaining in the resin from solvent
processing could artificially lower the Tg measurement. To obtain a
more accurate Tg, a resin sample was first subjected to
preconditioning in a TGA (thermal gravimetric analysis) instrument.
It was placed into a stainless steel DSC pan and heated under
nitrogen atmosphere from room temperature to 150.degree. C. at a
rate of 5.degree. C./min. The sample was then transferred to a
differential scanning calorimeter with modulating capability (TA
Instruments Q2000 MDSC with Universal software V4.3A). On the first
heating cycle, the sample was heated under nitrogen atmosphere from
-120.degree. C. to 125.degree. C. at a rate of 5.degree. C./min.
modulating at .+-.0.796.degree. C./min. Next, it was cooled to
-120.degree. C. at 5.degree. C./min. modulating at
.+-.0.796.degree. C./min. For the second heating cycle, the sample
was heated under the same conditions as those used in the first
heating cycle. The midpoint of the second heating cycle is reported
as the Tg of the sample.
[0095] Each resin was reduced to 70 weight percent solids in
n-butyl acetate (n-BuOAc). The solutions were then evaluated for
color, clarity and solution viscosity. Platinum-Cobalt color was
measured with a Gardco LICO 100 colorimeter in accordance with ASTM
method D 1209. Color values ranging from 0 to 100 are colorless to
very slight yellow color, respectively.
[0096] Clarity of the solutions was measured with a BYK-Gardner
haze-guard plus instrument according to ASTM method D 1003, Method
A, and is reported as percent haze.
[0097] Solution viscosity was determined using a Brookfield Model
LV DV II+ Pro viscometer. Viscosity was measured in a 4 oz. jar at
100 rpm using spindle #63. Viscosity readings below 1000 centipoise
are considered to be very low.
[0098] As shown in Table 1, polyesters P2, P3, and P4 have low
color, good clarity and low viscosity. All are suitable for
blending with a TSA resin and formulating into a high solids,
solvent borne thermosetting coating.
TABLE-US-00001 TABLE 1 Polyester Resin Charge Weights (Grams) and
Determined Resin Properties Comparative Polyester Formulation
Example P1 Example P2 Example P3 Example P4 Mole % TMCD in
Polyester 0 75 100 100 Stage 1 NPG.sup.(a), (b) 435.38 95.84 -- --
TMCD.sup.(a), (c) -- 398.10 510.45 510.47 TMP.sup.(d) 35.91 36.53
36.71 36.71 AD.sup.(e) 293.41 258.28 248.36 248.37 CHDA.sup.(g)
345.69 304.31 292.62 HHPA.sup.(h) -- -- -- 262.02 Fascat 4100
catalyst.sup.(f) 1.14 1.12 1.12 1.09 Xylene process solvent 22.84
22.48 22.40 21.78 Stage 2 TMP 35.91 36.53 36.71 36.71 Total Charge
1170.28 1153.19 1148.37 1117.15 Minus Theo. Condensate 142.00
124.70 119.81 89.22 Yield 1028.28 1028.49 1028.56 1027.93
Determined Resin Properties AN (mg KOH/g resin) 5 8 5 4 OH# (mg
KOH/g resin) 103 103 94 92 M.sub.n (daltons) 1959 1937 2106 2182
T.sub.g (.degree. C.) -27.7 -6.7 1.3 7.8 Resin Properties at 70 wt.
% in n- BuOAc Platinum-Cobalt Color 0 1 11 55 Clarity (% Haze) 0.83
0.53 0.98 1.55 Viscosity, cP 339 380 894 760 .sup.(a)Includes a
glycol excess of 1 wt. % based on calculated charge weights
.sup.(b)2,2-Dimethyl-1,3-propanediol (Eastman)
.sup.(c)2,2,4,4-tetramethy1-1,3-cyclobutanediol (Eastman)
.sup.(d)Trimethylolpropane (Perstorp) .sup.(e)Adipic acid (DuPont)
.sup.(f)Butylstannoic acid (Arkema)
.sup.(g)1,4-Cyclohexanedicarboxylic acid .sup.(h)Hexahydrophthalic
anhydride
[0099] Preparation of TSA/Aliphatic Polyester Blends
[0100] Examples B3, B4, B5, B7, B8, B9, B11, B12, and B13
illustrate blends of a TSA with the aliphatic polyesters of the
invention, while examples B1, B2, B6, and B10 are comparative
examples. The properties of the TSA/aliphatic polyester blends are
listed in Table 2.
[0101] The aliphatic polyester resins were evaluated for
compatibility with a commercially available TSA resin, MACRYNAL.TM.
SM 515/70BAC (available from Cytec Surface Specialties).
MACRYNAL.TM. SM 515 is a hydroxy functional acrylic that is
crosslinkable with aliphatic polyisocyanates. This TSA resin is
suggested for use by the manufacturer in air-drying and forced
drying two pack high solids thermosetting coatings.
[0102] The TSA/polyester resin blends were evaluated at 70 weight
percent solids in n-butyl acetate at TSA:polyester weight ratios of
85:15, 75:25 and 65:35. MACRYNAL.TM. SM 515 was supplied as a 70
weight percent solution in n-butyl acetate, and all of the
polyester resins were reduced to 70 weight percent solids in
n-butyl acetate. The appropriate amount of acrylic and polyester
resin solutions were combined in a 4 oz. jar as indicated in Table
2. The solutions were then rolled at room temperature for 24 hours
to thoroughly mix the components.
[0103] The viscosity of the TSA/polyester blends was determined
using a Brookfield Model LV DV II+ Pro viscometer. Viscosity was
measured in the 4 oz. jar at 20 rpm using spindle #63 and is
reported in centipoise. A portion of each TSA/polyester blend was
cast as a 10 mil wet film onto glass and force-dried for 7 hrs. at
80.degree. C. (176.degree. F.) then dried at room temperature
drying for 4 days before evaluation.
[0104] The Tg of the blends was determined on samples of the dried
cast films using a differential scanning calorimeter with
modulating capability (TA Instruments Q2000 MDSC with Universal
software V4.3A). On the first heating cycle, the sample was heated
under helium atmosphere from -120.degree. C. to 125.degree. C. at a
rate of 5.degree. C./min. and modulating at .+-.0.531.degree. C./40
sec. The sample then was quench-cooled with liquid nitrogen to
-120.degree. C. For the second heating cycle, the sample was heated
under the same conditions as those used in the first heating cycle.
The midpoint of the second heating cycle is reported as the Tg of
the sample.
[0105] The compatibility of the aliphatic polyester with the TSA
resin was determined by measuring the percent haze of the dried
films according to ASTM method D 1003, Method A, using a
BYK-Gardner HAZE-GARD PLUS.TM. instrument.
[0106] Table 2 shows that the viscosity of the TSA resin was
lowered when blended with any of the polyesters. Viscosity
decreases as the polyester content increases. In addition,
comparative examples B2, B6, and B10 show the greatest reduction in
Tg from the TSA alone, especially as the polyester content
increases. Example blends B3, B4, B5, B7, B8, B9, B11, B12 and B13
have less impact on Tg. The combination of TMCD/HHPA in polyester
P4 exhibits the greatest Tg retention. At 35% polyester content,
Example blend B13 made from polyester P4 experienced only a
7.degree. C. drop from the original Tg of the TSA versus a
35.degree. C. drop for Comparative blend B10 containing polyester
P1.
[0107] The compatibility of Example polyesters P2, P3 and P4 with
the TSA, as indicated by percent haze were similar to blends made
from Comparative polyester P1 and the TSA alone.
TABLE-US-00002 TABLE 2 Properties of TSA/Aliphatic Polyester Blends
TSA/Polyester 100/0 85/15 75/25 65/35 Example Blend B1.sup.(a)
B2.sup.(a) B3 B4 B5 B6.sup.(a) B7 B8 B9 B10.sup.(a) B11 B12 B13
Mole % TMCD -- 0 75 100 100 0 75 100 100 0 75 100 100 in Polyester
Grams.sup.(b) Cytec Macrynal SM 100 85 85 85 85 75 75 75 75 65 65
65 65 515 TSA Resin Comparative P1 0 15 0 0 0 25 0 0 0 35 0 0 0
Example P2 0 0 15 0 0 0 25 0 0 0 35 0 0 Example P3 0 0 0 15 0 0 0
25 0 0 0 35 0 Example P4 0 0 0 0 15 0 0 0 25 0 0 0 35 Properties
Viscosity at 2897 1566 1704 2040 1962 1254 1404 1908 1872 1044 1116
1644 1624 70 Wt. % Solids, cP T.sub.g,.degree. C. 37 25 32 33 34 13
25 31 32 2 22 27 30 Haze, % 0.11 0.22 0.14 0.13 0.11 0.38 0.40 0.11
0.18 0.12 0.22 0.26 0.17 .sup.(a)Comparative example. .sup.(b)All
resins are 70 wt. % solids in n-BuOAc.
[0108] Preparation of Polyurethane Coatings
[0109] White-pigmented polyurethane coatings were prepared from
aliphatic polyester resins P1, P3, and P4 and are shown in Table 3.
The resins were crosslinked with the triisocyanurate of
1,6-hexamethylene diisocyanate at a 1.1:1 NCO:OH ratio.
[0110] The Part A aliphatic polyester and pigment were added to a
500-mL stainless steel beaker. A cowles disperser was used to grind
the resin and pigment to a 7+ Hegman for about 5 min. at 5000 rpm.
The flow aid then was added and thoroughly mixed for a few minutes.
Finally, the catalyst and solvent blend were added and thoroughly
mixed. The total Part A mixture was transferred into a glass jar
and rolled until needed. The Part B crosslinker was added to Part A
and thoroughly mixed with a wooden tongue depressor then filtered
through a Hayward PE 100 PN164 300M felt paint filter inside a
medium mesh paper filter.
[0111] Coating viscosity was determined with a Gardco mini Ford dip
cup #4. The initial viscosity measurement was made after combining
and thoroughly mixing Part B with Part A. Viscosity was then
measured every two hours thereafter and is shown in Table 3.
[0112] A wire wound rod was used to apply the coating to glass
microscope slides and polished cold rolled steel test panels with
Bonderite 1000 pretreatment. The rod was selected to achieve a
1.5.+-.0.2 mil dry film thickness.
[0113] The coatings were force-dried 30 minutes at 250.degree. F.
(121.1.degree. C.). With the exception of Konig pendulum hardness,
all of the coating mechanical properties were determined after 21
days ambient aging. Specular gloss, distinctness of image,
reflectance, color, hardness, flexibility, solvent resistance,
chemical resistance and accelerated weathering (UVA and constant
humidity) resistance of the coatings were determined and reported
in Tables 4-9.
[0114] Dry film thickness (abbreviated "DFT") was measured with a
Fischerscope MMS Multi Measuring System permascope (Fischer
Technology) using the probe for ferrous substrates. Specular gloss
was measured with a BYK-Gardner micro-TRI-gloss meter in accordance
with ASTM method D 523. Distinctness of image (abbreviated "DOI")
was measured with a BYK-Gardner wave-scan DOI instrument according
to ASTM method E 430.
[0115] Color (CIE L*a*b*) and reflectance (CIE Y) values were
measured with a HunterLab UltraScan PRO spectrophotometer in
accordance with ASTM method E 313. Values were calculated using D65
illuminant and 10-degree observer. MEK double rub solvent
resistance was performed with a 32 oz. ball peen hammer wrapped in
16 layers of cotton cheesecloth in accordance with ASTM method
D1308. The number passed is reported as the last rub until any
breakthrough of the coating to metal was observed. The test was run
to a maximum of 300 double rubs with observations made on the left,
middle and right side of the rubbed path.
[0116] Hardness was determined by three methods: a BYK-Gardner
pendulum hardness tester using ASTM method D 4366; by pencil test
using ASTM method D 3363; and with an Instron Wilson-Wolpert Tukon
2100B indentation hardness tester using ASTM method E 384. For
pendulum hardness, the Konig method (abbreviated "KPH") is
reported. KPH was followed over the course of 21 days. The first
measurement, Day 1, was taken 24 hours after cure at 250.degree. F.
For pencil hardness, the value reported is the last pencil that did
not cut through the coating to metal. Tukon hardness was measured
on coatings applied to glass microscope slides. The instrument was
set to run with a 10 g weight and 13 second indent time using
20.times. magnification. Tukon hardness is reported using the Knoop
scale (abbreviated "HK").
[0117] Flexibility was measured as impact resistance with a Gardco
Model 172 universal impact tester in accordance with ASTM method D
2794. The values reported are the last impact to not produce any
crack in the coating film or delamination of the coating from the
substrate.
[0118] Resistance to a 50% solution of sulfuric acid
(H.sub.2SO.sub.4) was performed under ambient conditions for 36
days and measured according to ASTM method D 1308. A drop of the
acid solution was placed onto the coating, covered with a watch
glass and sealed with paraffin wax. Test areas were rinsed with
water before inspecting for blister formation.
[0119] To gage outdoor durability, the coatings were subjected to
QUVA (340 nm) accelerated weathering using a QUV/SE instrument
(Q-Lab). The test condition for `general metal` coatings per ASTM
method D 4587 was selected that includes 4 hours UV exposure at
60.degree. C. followed by 4 hours condensation at 50.degree. C.
Test panel edges and back were taped to protect against rust
formation. Measurements were taken 2 hours into the UV light cycle
to ensure a dry surface and consistency of measurement. Test panels
were rotated after each observation interval. The coatings were
tested for gloss retention (20.degree. and 60.degree. per ASTM
method D 523) and color change (Hunter .DELTA.E* and Yellowness
Index, ASTM method E 308 and ASTM method D 1925). The results are
shown in Tables 5 and 6.
[0120] The outdoor durability of a coating also was determined by
testing its water resistance using controlled condensation as
described in ASTM method D 4585. The coatings were placed in a
Cleveland condensing type humidity cabinet (Q-Lab Model QCT/ADO)
for continuous 60.degree. C. misting with deionized water. The
edges and back of the test panels were taped to protect against
rust formation. They were rotated after each observation interval.
The coatings were evaluated for gloss retention (20.degree. and
60.degree. per ASTM D 523) and degree of blistering (using ASTM
method D 714). The results are shown in Tables 7, 8 and 9.
[0121] Table 3 shows that example coatings C2 and C3 show similar
pot lives as comparative example C1 (based on NPG glycol as the
diol). Coating mechanical properties are presented in Table 4.
[0122] Examples C2 and C3 exhibit higher gloss, DOI, and
reflectance than comparative example C1. Color is relatively
similar for all of the coatings. Examples C2 and C3 also have a
more uniform and brilliant appearance as indicated by the higher
gloss, DOI and reflectance values.
[0123] MEK double rub solvent resistance was higher across the
coating surface for examples C2 and C3 than comparative example C1.
In particular, the combination of TMCD/CHDA in example C2 showed no
breakthrough of the coating to the substrate.
[0124] Hardness, as measured by pencil, Tukon and Konig pendulum
tests, is greater for examples C2 and C3. In addition, examples C2
and C3 display similar flexibility to comparative example C1.
Examples C2 and C3 were unaffected after 36 days exposure to
H.sub.2SO.sub.4 solution, whereas comparative example C1
blistered.
[0125] After .about.3500 hours QUVA (340 nm) accelerated weathering
exposure, examples C2 and C3 had greater gloss retention than
comparative example C1 (see Table 5). Gloss retention of examples
C2 and C3 was about 4.5 times longer. Examples C2 and C3 also
exhibited a Hunter .DELTA.E* shift and Yellow Index shift of only
one unit over the entire test period (see Table 6).
[0126] Examples C2 and C3 had greater gloss retention with little
or no blister development than comparative example C1 when
subjected to Cleveland humidity testing (see Tables 7, 8 and 9). In
particular, example C3 retained 73% of its original 20.degree.
gloss after 10,000 hours exposure with no blister formation.
TABLE-US-00003 TABLE 3 Comparative and Example Polyurethane Coating
Formulation Weights (Grams) and Pot Life Coating Formulation
Comparative Example Example Example C1 C2 C3 Polyester Formulation
from Example 1 P1 P3 P4 Mole % TMCD in Polyester 0 100 100 Part
A-Grind Polyester resin (70 wt. % in n-BuOAc) 76.23 76.23 76.45
Ti-Pure R960 TiO.sub.2 pigment.sup.(a) 51.89 51.89 51.89 Part A-Let
Down BYK-300.sup.(b) (10 wt. % in n-BuOAc) 2.59 2.59 2.59 Fascat
4202.sup.(c) catalyst 0.82 0.82 0.82 (1 wt. % in n-BuOAc) Solvent
blend (45/45/10 40.99 40.99 40.94 Xylene/MAK/EEP) Total Part A
172.52 172.52 172.70 Part B Desmodur N 3390 BA/SN(d) (90 wt. 27.48
27.48 27.30 % in 1/1 n-BuOAc/solvent naptha 100) Total Parts A + B
200.00 200.00 200.00 Pot Life (Coating Viscosity, sec.) 0 Hours 9.2
11.6 9.9 1 Hour 10.0 12.1 10.2 2 Hours 11.1 12.0 10.3 3 Hours --
12.4 -- 4 Hours 13.1 12.9 11.6 5 Hours 14.7 -- -- 6 Hours 17.8 --
19.4 .sup.(a)DuPont Titanium Technologies. .sup.(b)BYK-Chemie.
.sup.(c)Arkema (dibutyltindilaurate). .sup.(d)Bayer MaterialScience
(aliphatic polyisocyanate HDI trimer).
TABLE-US-00004 TABLE 4 Comparative and Example Polyurethane Coating
Properties Coating Formulation Comparative Ex- Ex Example ample
ample C1 C2 C3 Polyester Formulation from Example 1 P1 P3 P4 Mole %
TMCD in Polyester 0 100 100 Gloss -20.degree. 72 79 81 -60.degree.
87 88 90 DOI 90 93 93 Reflectance (Y-value) 88 92 91 Color L* 95.33
96.69 96.23 a* -1.24 -1.08 -1.11 b* -0.02 -0.31 -0.41 MEK Dbl Rubs
(# passed) Left 285 300+ 273 Middle 300+ 300+ 300+ Right 133 300+
289 Pencil Hardness 1 H 3 H 3 H Tukon Hardness (HK) <1 13.9 15.7
Konig Pendulum Hardness (sec.) Day 1 16 146 157 Day 2 17 157 167
Day 7 17 158 169 Day 14 17 162 171 Day 21 17 161 170 Impact
Resistance (in.-lb.) Forward 150 150 174 Reverse 126 84 78 50%
H.sub.2SO.sub.4 Resistance Appearance after 36 days Moderate No No
blistering. effect. effect.
TABLE-US-00005 TABLE 5 QUVA Accelerated Weathering Gloss Retention
of Comparative and Example Polyurethane Coatings Coating
Formulation Comparative Example Example Example C1 C2 C3 Polyester
Formulation from Example 1 P1 P3 P4 Mole % TMCD in Polyester 0 100
100 Hours Exposure 20.degree. Gloss 0 70.5 80.4 81.9 250 70.3 78.0
82.8 500 67.9 79.1 82.8 750 14.1 77.8 82.5 1000 -- 71.8 79.5 1250
-- 64.5 81.6 1500 -- 54.4 68.4 1750 -- 43.1 65.1 2000 -- 37.8 64.1
2244 -- 29.9 48.7 2478 -- 24.6 37.0 2728 -- 18.3 23.3 2978 -- 17.4
24.4 3228 -- 20.0 22.7 3478 -- 13.6 11.3 Hours Exposure 60.degree.
Gloss 0 85.9 87.4 90.5 250 86.0 85.5 90.4 500 85.1 86.6 90.2 750
48.9 87.4 90.7 1000 -- 86.6 89.1 1250 -- 85.0 89.7 1500 -- 81.9
84.2 1750 -- 77.2 84.1 2000 -- 75.5 84.2 2244 -- 71.9 78.6 2478 --
67.0 71.4 2728 -- 61.0 66.1 2978 -- 61.4 64.1 3228 -- 63.8 58.3
3478 -- 56.6 51.1
TABLE-US-00006 TABLE 6 QUVA Accelerated Weathering Color Change of
Comparative and Example Polyurethane Coatings Coating Formulation
Comparative Example Example Example Cl C2 C3 Polyester Formulation
from Example 1 P1 P3 P4 Mole % TMCD in Polyester 0 100 100 Hours
Exposure .DELTA.E 0 0.0 0.0 0.0 250 0.5 0.2 0.3 500 0.5 0.4 0.2 750
0.4 0.3 0.2 1000 -- 0.6 0.4 1250 -- 0.4 0.3 1500 -- 0.8 0.9 1750 --
0.8 0.6 2000 -- 0.6 0.5 2244 -- 0.7 0.7 2478 -- 0.8 0.8 2728 -- 0.8
0.9 2978 -- 1.0 1.0 3228 -- 0.9 0.8 3478 -- 1.0 0.9 Hours Exposure
Yellow Index 0 -1.9 -1.8 -1.9 250 -1.5 -1.7 -1.6 500 -1.4 -1.7 -1.7
750 -1.5 -1.7 -1.7 1000 -- -1.6 -1.6 1250 -- -1.5 -1.5 1500 -- -1.4
-1.3 1750 -- -1.5 -1.6 2000 -- -1.4 -1.5 2244 -- -1.2 -1.2 2478 --
-1.3 -1.2 2728 -- -1.3 -1.2 2978 -- -1.1 -1.1 3228 -- -1.2 -0.9
3478 -- -1.0 -1.0
TABLE-US-00007 TABLE 7 Cleveland Humidity Accelerated Weathering
20.degree. Gloss Retention of Comparative and Example Polyurethane
Coatings Coating Formulation Comparative Example Example Example C1
C2 C3 Polyester Formulation from Example 1 P1 P3 P4 Mole % TMCD in
Polyester 0 100 100 Hours Exposure 20.degree. Gloss 0 65.5 80.3
81.3 24 65.9 80.3 82.1 48 62.9 80 82 148 61.8 79.7 81.9 288 57.6
80.6 82.2 456 45.4 80.1 81.6 600 46.3 80.4 81.9 768 39.4 79.5 81.8
936 34.5 76.8 80.3 1104 28.2 77.9 80.6 1272 14.4 77.2 80.2 1532 13
77.1 79.6 1700 -- 76.3 79.7 1868 -- 77.2 80.3 2036 -- 77.1 80.9
2252 -- 74.9 79.7 2500 -- 74.5 79.1 2740 -- 75.3 79.1 3004 -- 73.7
80.1 3100 -- 75.4 79.8 3316 -- 72.8 79.6 3580 -- 71.2 79.8 3820 --
64.7 79.7 4080 -- 66.9 78.7 4330 -- 59.7 78.8 4640 -- 54.1 78.4
4928 -- 50.1 78.4 5168 -- 42.6 74.8 5418 -- 41.4 76.1 5638 -- 37
75.6 5854 -- 29.2 76.3 6142 -- 28.5 73.1 6430 -- 14.1 70.6 6622 --
-- 71.6 6910 -- -- 72.7 7390 -- -- 69.4 7678 -- -- 69.7 8086 -- --
64.1 9326 -- -- 60.6 9734 -- -- 52.4 10046 -- -- 59.1
TABLE-US-00008 TABLE 8 Cleveland Humidity Accelerated Weathering
60.degree. Gloss Retention of Comparative and Example Polyurethane
Coatings Coating Formulation Cornparative Example Example Example
C1 C2 C3 Polyester Formulation from Example 1 P1 P3 P4 Mole % TMCD
in Polyester 0 100 100 Hours Exposure 60.degree. Gloss 0 85.2 87.4
89.8 24 85.3 87.3 89.8 48 84.1 87.4 89.6 148 83.8 87.6 89.7 288
81.7 87.5 89.7 456 69.3 87.3 89.6 600 68.5 87.3 90.0 768 62.8 87.5
90.2 936 56.7 85.5 89.0 1104 53.7 85.2 88.0 1272 33.1 85.7 88.5
1532 28.0 84.9 88.5 1700 -- 84.8 87.9 1868 -- 85.4 89.5 2036 --
86.2 89.1 2252 -- 84.6 88.3 2500 -- 84.9 88.6 2740 -- 85.1 88.1
3004 -- 85.5 89.0 3100 -- 85.5 88.6 3316 -- 84.6 88.4 3580 -- 84.6
90.3 3820 -- 81.0 88.9 4080 -- 82.4 89.0 4330 -- 79.3 87.9 4640 --
77.3 88.4 4928 -- 74.7 88.0 5168 -- 70.3 87.5 5418 -- 70.9 85.9
5638 -- 66.4 86.5 5854 -- 60.7 86.7 6142 -- 61.5 84.6 6430 -- 48.9
84.8 6622 -- -- 84.9 6910 -- -- 84.8 7390 -- -- 82.5 7678 -- --
82.9 8086 -- -- 80.2 9326 -- -- 77.8 9734 -- -- 77.9 10046 -- --
78.4
TABLE-US-00009 TABLE 9 Cleveland Humidity Accelerated Weathering
Blister Rating of Comparative and Example Polyurethane Coatings
Coating Formulation Comparative Example Example Example C1 C2 C3
Polyester Formulation from Example 1 P1 P3 P4 Mole % TIVICD in
Polyester 0 100 100 Hours Exposure Blister Rating (Size/Density) 0
None/None None/None None/ None 24 None/None None/None None/ None 48
None/None None/None None/ None 148 None/None None/None None/ None
288 8/Medium None/None None/ None 456 6/Medium None/None None/ None
600 4/Medium None/None None/ None 768 4/Dense None/None None/ None
936 4/Dense None/None None/ None 1104 4/Dense None/None None/ None
1272 2/Dense None/None None/ None 1532 2/Dense None/None None/ None
1700 -- None/None None/ None 1868 -- None/None None/ None 2036 --
None/None None/ None 2252 -- None/None None/ None 2500 -- None/None
None/ None 2740 -- None/None None/ None 3004 -- None/None None/
None 3100 -- None/None None/ None 3316 -- None/None None/ None 3580
-- None/None None/ None 3820 -- None/None None/ None 4080 --
None/None None/ None 4330 -- None/None None/ None 4640 -- None/None
None/ None 4928 -- None/None None/ None 5168 -- 6/Few None/ None
5418 -- 6/Few None/ None 5638 -- 6/Few None/ None 5854 -- 6/Few
None/ None 6142 -- 6/Few None/ None 6430 -- 6/Few None/ None 6622
-- -- None/ None 6910 -- -- None/ None 7390 -- -- None/ None 7678
-- -- None/ None 8086 -- -- None/ None 9326 -- -- None/ None 9734
-- -- None/ None 10046 -- -- None/ None
* * * * *