U.S. patent application number 13/394805 was filed with the patent office on 2012-07-12 for polyester resin and method for preparing the same.
Invention is credited to Dong-Jin Kim, Jong-Ryang Kim, Roy Lee, Yoo-Jin Lee, Jae-Bong Lim, Jyu-Tae Park, Won-Jae Yoon.
Application Number | 20120177854 13/394805 |
Document ID | / |
Family ID | 43732983 |
Filed Date | 2012-07-12 |
United States Patent
Application |
20120177854 |
Kind Code |
A1 |
Lee; Roy ; et al. |
July 12, 2012 |
POLYESTER RESIN AND METHOD FOR PREPARING THE SAME
Abstract
A polyester resin copolymerized with isosorbide and
1,4-cyclohexane dimethanol and having an improved impact strength,
and a method for preparing the same are disclosed. The
copolymerized polyester resin has an alternating structure of acid
moieties which are derived from acid components and diol moieties
which are derived from diol components, wherein the acid components
comprise terephthalic acid, and the diol components comprise (i)
5.about.99 mol % of 1,4-cyclohexanedimethanol and (ii) 1.about.60
mol % of isosorbide with respect to the total diol components.
Inventors: |
Lee; Roy; (Seoul, KR)
; Kim; Jong-Ryang; (Gyeonggi-do, KR) ; Lim;
Jae-Bong; (Gyeonggi-do, KR) ; Yoon; Won-Jae;
(Seoul, KR) ; Kim; Dong-Jin; (Seoul, KR) ;
Park; Jyu-Tae; (Seoul, KR) ; Lee; Yoo-Jin;
(Seoul, KR) |
Family ID: |
43732983 |
Appl. No.: |
13/394805 |
Filed: |
September 13, 2010 |
PCT Filed: |
September 13, 2010 |
PCT NO: |
PCT/KR2010/006229 |
371 Date: |
March 7, 2012 |
Current U.S.
Class: |
428/35.7 ;
528/300 |
Current CPC
Class: |
G06F 8/65 20130101; C08G
63/672 20130101; Y10T 428/1352 20150115; C08G 63/78 20130101 |
Class at
Publication: |
428/35.7 ;
528/300 |
International
Class: |
C08G 63/672 20060101
C08G063/672; B32B 1/02 20060101 B32B001/02 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 14, 2009 |
KR |
10-2009-0086244 |
Claims
1. A copolymerized polyester resin having an alternating structure
of acid moieties which are derived from acid components and diol
moieties which are derived from diol components, wherein the acid
components comprise terephthalic acid, and the diol components
comprise (i) 5.about.99 mol % of 1,4-cyclohexanedimethanol and (ii)
1.about.60 mol % of isosorbide with respect to the total diol
components.
2. The copolymerized polyester resin according to claim 1, wherein
the acid components further comprise one or more copolymerization
acid components which are selected from the group consisting of
aromatic dicarboxylic acid components of 8.about.14 carbon numbers,
aliphatic dicarboxylic acid components of 4.about.12 carbon numbers
and mixtures thereof, and the amount of the copolymerization acid
components is 0.about.50 mol % with respect to the total acid
components.
3. The copolymerized polyester resin according to claim 1, wherein
the amount of isosorbide (ISB mol %) is in the range of the
following Equation 1, 0.0012(CHDM mol %).sup.2-0.2401(CHDM mol
%)+14.136<=ISB mol %<=0.0049(CHDM mol %).sup.2-0.2255(CHDM
mol %)+71.176 [Equation 1] wherein CHDM mol % represents the amount
of 1,4-cyclohexane dimethanol.
4. The copolymerized polyester resin according to claim 1, wherein
the diol components comprise (i) 8.about.91 mol % of
1,4-cyclohexanedimethanol and (ii) 4.about.40 mol % of isosorbide
with respect to the total diol components.
5. The copolymerized polyester resin according to claim 1, wherein
glass transition temperature (Tg) of the polyester resin is more
than 90.degree. C., and notch izod impact strength of the polyester
resin is more than 50 J/m.
6. The copolymerized polyester resin according to claim 1, wherein
intrinsic viscosity of the polyester resin is more than 0.35 dl/g,
and the intrinsic viscosity is measured at the temperature of
35.degree. C. while the polyester resin is dissolved with
orthochlorophenol to a concentration of 1.2 g/dl.
7. A polyester resin article selected from the group consisting of
a film, a sheet, a drink bottle, a baby bottle, a fiber, and an
optical product which is produced with the copolymerized polyester
resin according to one of claims 1.about.6.
8. A method for preparing polyester resin, comprising the steps of:
carrying out an esterification reaction or a trans-esterification
reaction of acid components and diol components at the increased
pressure of 0.2.about.3.0 kg/cm.sup.2 and the temperature of
200.about.300.degree. C. during an average retention time of
2.about.10 hours; and carrying out a polycondensation reaction for
a product of the esterification reaction or the
trans-esterification reaction at the reduced pressure of
400.about.0.1 mmHg and at the temperature of 240.about.300.degree.
C. during an average retention time of 1.about.10 hours, wherein
the acid components comprise terephthalic acid, and the diol
components comprise (i) 5.about.99 mol % of
1,4-cyclohexanedimethanol and (ii) 1.about.60 mol % of isosorbide
with respect to the total diol components.
9. The method for preparing polyester resin according to claim 8,
wherein the amount of isosorbide (ISB mol %) is in the range of the
following Equation 1, 0.0012(CHDM mol %).sup.2-0.2401(CHDM mol
%)+14.136<=ISB mol %<=0.0049(CHDM mol %).sup.2-0.2255(CHDM
mol %)+71.176 [Equation 1] wherein CHDM mol % represents the amount
of 1,4-cyclohexane dimethanol.
10. The method for preparing polyester resin according to claim 8,
wherein the diol components comprise (i) 8.about.91 mol % of
1,4-cyclohexanedimethanol and (ii) 4.about.40 mol % of isosorbide
with respect to the total diol components.
Description
TECHNICAL FIELD
[0001] This invention relates to a polyester resin and a method for
preparing the same, and more specifically to a polyester resin
copolymerized with isosorbide and 1,4-cyclohexane dimethanol and
having an improved impact strength, and a method for preparing the
same.
BACKGROUND ART
[0002] The polyester resin has been widely used in fields of the
packing materials, the forming products and the films, and is one
of the environment-friendly plastics which has no endocrine
disruptors. Recently, in the polycarbonate which has been used as
the heat-resisting container for food, harmfulness of bisphenol-A
to the human being has been revealed. So, the demand for the
environment-friendly transparent and heat-resisting polyester resin
has more increased. The polyester resin which is copolymerized with
at least two glycol or dicarboxylic acid components has been
commercially widely used to improve a moldability thereof and to
remove a crystallinity thereof. In the case of homopolyester which
is polymerized with only terephthalic acid and ethyleneglycol,
material properties and heat-resistance thereof can be enhanced
through a stretching-induced crystallization and heat-setting.
However, there are limitations on application and enhancement of
heat-resistance. In the case of polyester which is copolymerized
with at least two glycol or terephthalic acid components, there is
a disadvantage that it is difficult to enhance heat-resistance
thereof by stretching or crystallize process. As another method to
enhance heat-resistance of the polyester, it is known that the
isosorbide which is an environment-friendly diol compound derived
from starch and represented by following Formula I, is used as one
of monomers.
##STR00001##
[0003] According to the results of past studies, isosorbide has low
activity as a secondary alcohol so that it is difficult to prepare
high viscous polyester which can be used for manufacturing sheets
or bottles. However, recent U.S. Pat. No. 5,959,066 discloses a
method for preparing polyester having the intrinsic viscosity of
more than 0.35 dl/g by melt polymerization using terephthalic acid
or dimethylterephthalate and various diols comprising isosorbide.
The polyester resin having the intrinsic viscosity of more than
0.35 dl/g is used for optical products and coating, and the
polyester resin having the intrinsic viscosity of more than 0.4
dl/g is used for CD, and the polyester resin having the intrinsic
viscosity of more than 0.5 dl/g can be used for a bottle, a film, a
sheet and injection molding. Moreover, U.S. Pat. No. 6,063,464
discloses a method for preparing the polyester having the intrinsic
viscosity of more than 0.15 dl/g by melt polymerization using the
glycol components comprising isosorbide. The above patents disclose
a method for polymerizing polyester using common catalysts with all
of acids and diols comprising isosorbide, however, it seems that a
composition for higher impact strength is needed to be used for
normal plastics. As shown in Examples of U.S. Pat. No. 6,063,464,
notch izod impact strength of products produced by adding glass
fiber of 29.6% to polyesters comprising isosorbide of 3, 6, and
13%, shows the range of 43.about.116 J/m according to the amount of
isosorbide, however, impact strength of a product without glass
fiber is not mentioned. If glass fiber is added, usually impact
strength is enhanced, but transparency is extremely lowered and
applications are limited due to the harmfulness of glass fiber.
DISCLOSURE OF INVENTION
Technical Problem
[0004] Therefore, it is an object of the present invention to
provide a copolymerized polyester resin having superior
heat-resistance and impact strength and the method for preparing
the same.
[0005] It is other object of the present invention to provide a
copolymerized polyester resin having a high molecular weight by
using 1,4-cyclohexanedimethanol and isosorbide as diol components
and the method for preparing the same.
Solution to Problem
[0006] To accomplish these objects, the present invention provides
a copolymerized polyester resin having an alternating structure of
acid moieties which are derived from acid components and diol
moieties which are derived from diol components, wherein the acid
components comprise terephthalic acid, and the diol components
comprise (i) 5.about.99 mol % of 1,4-cyclohexanedimethanol and (ii)
1.about.60 mol % of isosorbide with respect to the total diol
components.
[0007] The present invention also provides a method for preparing
polyester resin, comprising the steps of: carrying out an
esterification reaction or a trans-esterification reaction of acid
components and diol components at the increased pressure of
0.2.about.3.0 kg/cm.sup.2 and the temperature of
200.about.300.degree. C. during an average retention time of
2.about.10 hours; and carrying out a polycondensation reaction for
a product of the esterification reaction or the
trans-esterification reaction at the reduced pressure of
400.about.0.1 mmHg and at the temperature of 240.about.300.degree.
C. during an average retention time of 1.about.10 hours, wherein
the acid components comprise terephthalic acid, and the diol
components comprise (i) 5.about.99 mol % of
1,4-cyclohexanedimethanol and (ii) 1.about.60 mol % of isosorbide
with respect to the total diol components. The polyester resin of
the present invention shows superior heat-resistance and impact
strength by using 1,4-cyclohexanedimethanol and isosorbide as diol
components.
Advantageous Effects of Invention
[0008] The polyester resin according to the present invention has
superior heat-resistance and impact strength because it use
1,4-cyclohexane dimethanol and isosorbide at the same time as diol
components.
BEST MODE FOR CARRYING OUT THE INVENTION
[0009] A more complete appreciation of the invention, and many of
the attendant advantages thereof, will be better appreciated by
reference to the following detailed description.
[0010] The copolymerized polyester resin according to the present
invention is prepared by copolymerization of acid components and
diol components, and has an alternating structure of acid moieties
which are derived from the acid components and diol moieties which
are derived from the diol components.
[0011] The acid components include terephthalic acid as a major
component. Specifically, the acid components can be composed
entirely of terephthalic acid, or, if necessary, may include a
minor amount of one or more copolymerization acid components
(copolymerization monomers) which are selected from the group
consisting of aromatic dicarboxylic acid components of 8.about.14
carbon numbers, aliphatic dicarboxylic acid components of
4.about.12 carbon numbers and mixtures thereof for improving the
properties of the produced polyester resin. The preferable amount
of the terephthalic acid component is 80.about.100 mol % with
respect to the total acid components. The preferable amount of the
copolymerization acid components is 0.about.50 mol %, more
preferably 0.1.about.40 mol %, most preferably 1.about.10 mol %,
and, generally 0.about.20 mol % with respect to the total acid
components. If the amount of the copolymerization acid components
is beyond the range, the properties of the polyester resin may be
insufficiently improved or even deteriorated. The aromatic
dicarboxylic acid components of 8.about.14 carbon numbers include
various aromatic dicarboxylic acid components which are
conventionally used for producing polyester resin, and examples
thereof include benzenedicarboxylic acid such as phthalic acid and
isophthalic acid, naphthalene dicarboxylic acid such as
2,6-naphthalene dicarboxylic acid, diphenyl dicarboxylic acid, and
so on, except terephthalic acid. The aliphatic dicarboxylic acid
components of 4.about.12 carbon numbers include various linear,
branched or cyclic aliphatic dicarboxylic acid components which are
conventionally used for producing polyester resin, and examples
thereof include cyclohexane dicarboxylic acid such as
1,4-cyclohexane dicarboxylic acid and 1,3-cyclohexane dicarboxylic
acid, sebasic acid, succinic acid, isodecylsuccinic acid, maleic
acid, fumaric acid, adipic acid, glutaric acid, azelaic acid, and
so on. In the present invention, one or more of the
copolymerization acid components can be used at the same time. In
this specification, the term "terephthalic acid or terephthalic
acid component" include terephthalic acid, alkyl ester (lower alkyl
(1.about.4 carbon numbers) ester such as monoalkyl, monoethyl,
dimethyl, diethyl or dibutyl ester) of terephthalic acid, and acid
anhydride thereof, which produce terephthaloyl moiety when reacted
with glycol component. Also, in this specification, the acid moiety
or the diol moiety represents residue which remains after
hydrogens, hydroxyl groups, or alkoxy groups are removed in the
polymerization reaction of the acid components and the diol
components.
[0012] The diol components of the present invention include (i)
5.about.99 mol %, preferably 5.about.95 mol %, more preferably
8.about.91 mol %, most preferably 20.about.91 mol % of
1,4-cyclohexane dimethanol (CHDM mol %) and (ii) 1.about.60 mol %,
preferably mol % range of the following Equation 1 and equal or
less than 60 mol %, more preferably 4.about.40 mol %, most
preferably 8.about.40 mol % of isosorbide (ISB mol %) with respect
to the total diol components.
0.0012(CHDM mol %).sup.2-0.2401(CHDM mol %)+14.136<=ISB mol
%<=0.0049(CHDM mol %).sup.2-0.2255(CHDM mol %)+71.176 [Equation
1]
[0013] The remaining components in the total diol components can be
selected from the group consisting of (iii) ethylene glycol, (iv)
other copolymerization diol components (monomers) for improving the
properties of the polyester resin such as diethylene glycol,
triethylene glycol, propanediol (for example, 1,2-propanediol and
1,3-propanediol), 1,4-butanediol, pentanediol, hexanediol (for
example, 1,6-hexanediol), neopentyl glycol
(2,2-dimethyl-1,3-propanediol), 1,2-cyclohexanediol,
1,4-cyclohexanediol, 1,2-cyclohexanedimethanol,
1,3-cyclohexanedimethanol, tetramethylcyclobutanediol, and mixtures
thereof. When other diol components which are not (i)
1,4-cyclohexanedimethanol and (ii) isosorbide are used, the major
component of the other diol components is preferably (iii) ethylene
glycol. Namely, the remaining diol components except (i)
1,4-cyclohexanedimethanol and (ii) isosorbide are preferably
composed of (iii) ethylene glycol. If (iv) the other
copolymerization diol components for improving the properties of
the polyester resin are used, the amount of (iv) the other
copolymerization diol components is preferably 0.about.50 mol %,
more preferably 0.1.about.40 mol %, and generally 1.about.10 mol %
with respect to the total diol components. In the ranges of (i)
1,4-cyclohexanedimethanol and (ii)
isosorbide(1,4:3,6-dianhydroglucitol) of the present invention, as
the amount of 1,4-cyclohexanedimethanol increases, the impact
strength of the produced polyester resin rapidly increases.
Therefore, in the present invention, (i) 1,4-cyclohexanedimethanol
and (ii) isosorbide improve the properties such as an impact
strength, a moldability of the produced polyester resin compared
with a homopolymer prepared with only terephthalic acid and
ethylene glycol. When the amount of 1,4-cyclohexanedimethanol is
less than 5 mol %, the impact strength of the polyester resin may
be undesirable. When the amount of 1,4-cyclohexane dimethanol is
more than 99 mol %, the amount of isosorbide is less than 1 mol %
and the heat-resistance of the polyester resin may decrease.
Meanwhile, when the amount of isosorbide is less than 1 mol %, the
heat-resistance of the polyester resin may be insufficient, and
when the amount of isosorbide is more than 60 mol %, the color of
the polyester resin may become yellow.
[0014] When the polyester resin of the present invention is molded
into a test sample of thickness of 3.2 mm, the notch izod impact
strength (ASTM D256 method, measuring temperature: 23.degree. C.)
of the test sample is generally more than 50 J/m. On the other
hand, when a polyester resin is prepared with ethylene glycol and
isosorbide, the test sample generally has the notch izod impact
strength of less than 50 J/m. When the polyester resin of the
present invention is subject to an annealing treatment at
300.degree. C. for 5 minutes, and is cooled to room temperature,
and then is re-heated with the temperature increasing speed of
10.degree. C./min, the polyester resin shows the glass transition
temperature (Tg) of more than 90.degree. C. Meanwhile, when the
polyester resin of the present invention is dissolved with
orthochlorophenol (OCP) to a concentration of 1.2 g/dl, the
polyester resin shows the intrinsic viscosity of more than 0.35
dl/g, preferably more than 0.40 dl/g, more preferably 0.45 dl/g at
the temperature of 35.degree. C. Since the polyester resin of the
present invention has superior heat-resistance and impact strength,
the polyester resin is suitable for producing polyester resin
article selected from the group consisting of a film, a sheet, a
drink bottle, a baby bottle, a fiber, an optical product, and so
on.
[0015] Hereinafter, the method for preparing polyester resin of the
present invention will be described. First, (a) the acid components
and the diol components are subject to an esterification reaction
or a trans-esterification reaction at the increased pressure of
0.2.about.3.0 kg/cm.sup.2 and the temperature of
200.about.300.degree. C. during an average retention time of
2.about.10 hours. Preferably, the acid components include (i)
80.about.100 mol % of terephthalic acid component and (ii)
0.about.20 mol % of copolymerization acid components which are
selected from the group consisting of aromatic dicarboxylic acid
components of 8.about.14 carbon numbers, aliphatic dicarboxylic
acid components of 4.about.12 carbon numbers and mixtures thereof.
The diol components includes (i) 5.about.99 mol % of
1,4-cyclohexane dimethanol, (ii) 1.about.60 mol % of isosorbide,
and optionally (iii) ethylene glycol and other copolymerization
diol components. Next, (b) the product of the esterification
reaction or the trans-esterification reaction is subject to a
polycondensation reaction at the reduced pressure of 400.about.0.1
mmHg and at the temperature of 240.about.300.degree. C. during an
average retention time of 1.about.10 hours to produce the polyester
resin of the present invention. Preferably, the pressure of the
polycondensation reaction eventually reaches to less than 2.0 mmHg,
and the esterification reaction or the trans-esterification
reaction and the polycondensation reaction are carried out under an
inert gas atmosphere.
[0016] The polymerization conditions for preparing the polyester
resin of the present invention will be described in more detail.
For preparing the copolymerized polyester resin with terephthalic
acid, isosorbide, and so on, the mole ratio of the total glycol
(diol) components comprising 1,4-cyclohexanedimethanol, isosorbide,
ethylene glycol and so on with respect to the total dicarboxylic
acid components comprising terephthalic acid and so on is
controlled to 1.05.about.3.0, and the esterification reaction is
carried out at the temperature of 200.about.300.degree. C.,
preferably 240.about.260.degree. C., more preferably
245.about.255.degree. C. and at the increased pressure of
0.1.about.3.0 kg/cm.sup.2, preferably 0.2.about.3.0 kg/cm.sup.2.
When the mole ratio of the total glycol components with respect to
the total dicarboxylic acid components is less than 1.05, the
dicarboxylic acid components may not fully react in the
polymerization reaction, which deteriorates the transparency of the
resin. When the mole ratio is more than 3.0, the polymerization
reaction rate may decrease and the productivity of the resin may be
unsatisfactory. The reaction time of the esterification reaction
(average retention time) is generally 100 minutes.about.10 hours,
preferably 2 hours.about.500 minutes, which can be varied according
to the reaction temperature, the reaction pressure, the mole ratio
of glycol components and dicarboxylic acid components, and so on.
The process for preparing polyester resin can be divided into the
esterification reaction (Step 1) and the polycondensation reaction
(Step 2). The esterification reaction does not require catalyst,
but catalyst can be used to reduce the reaction time. The
esterification reaction (Step 1) can be carried out in a batch-wise
manner or a continuous manner. Each reactant can be introduced into
a reactor separately, but it is preferable to introduce a slurry
including the glycol components and the dicarboxylic acid component
into the reactor. In this case, the glycol components which are
solid at room temperature (for example, isosorbide) can be
dissolved with water or ethylene glycol, and then mixed with the
terephthalic acid component to form a slurry. Alternatively, water
can be added to a slurry including terephthalic acid component,
glycol components and isosorbide to increase the solubility of
isosorbide, or the slurry can be prepared at the increased
temperature of more than 60.degree. C. so that isosorbide can be
melted in the slurry.
[0017] After completion of the esterification reaction (Step 1),
the polycondensation reaction (Step 2) is carried out. Before the
initiation of the polycondensation reaction, a poly-condensation
catalyst, a stabilizer, a brightening agent and other additives can
be added to the product of the esterification reaction. Examples of
the polycondensation catalyst include conventional titanium based
catalyst, germanium based catalyst, antimony based catalyst,
aluminum based catalyst, tin based catalyst, and mixtures thereof.
Examples of the preferable titanium based catalyst include
tetraethyl titanate, acetyl-tripropyl titanate, tetrapropyl
titanate, tetrabutyl titanate, polybutyl titanate, 2-ethylhexyl
titanate, octylene glycol titanate, lactate titanate,
triethanolamine titanate, acetylacetonate titanate, ethyl
acetoacetic ester titanate, isostearyl titanate, titanium dioxide,
titanium dioxide/silicon dioxide co-precipitates, titanium
dioxide/zirconium dioxide co-precipitates, and so on. Examples of
the preferable germanium based catalyst include germanium dioxide
and co-precipitates of germanium dioxide. As the stabilizer for the
polycondensation reaction, conventional various phosphor based
stabilizers, such as phosphoric acid, trimethyl phosphate, triethyl
phosphate, and so on, can be used. Preferably, the stabilizer is
introduced so that the amount of phosphor of the stabilizer is
10.about.100 ppm with respect to the total weight of the produced
polyester resin. When the amount of phosphor of the stabilizer is
less 10 ppm, the polyester resin may not be sufficiently stabilized
and the color of the polyester resin may become yellow. When the
amount of phosphor is more than 100 ppm, the polymerization degree
of the polyester resin may be insufficient. The brightening agent
is added to improve the color property of the polyester resin.
Examples of the brightening agent include conventional brightening
agent such as cobalt acetate, cobalt propionate. If necessary,
organic brightening agent can be used as the brightening agent. The
preferable amount of the brightening agent is 0.about.100 ppm with
respect to the total weight of the polyester resin. Generally, the
polycondensation reaction is carried out at the temperature of
240.about.300.degree. C., preferably 250.about.290.degree. C., more
preferably 260.about.280.degree. C. and at the reduced pressure of
400.about.0.1 mmHg. The reduced pressure of 400.about.0.1 mmHg is
maintained in order to remove by-products of the polycondensation
reaction or excess glycol. The polycondensation reaction can be
carried out until desirable intrinsic viscosity of the polyester
resin can be obtained, and, for example, can be carried out during
an average retention time of 1.about.10 hours.
MODE FOR THE INVENTION
[0018] Hereinafter, the following examples are provided to
illustrate the present invention in more detail, but the present
invention is not restricted or limited by the following
examples.
[0019] In the following Examples and Comparative Examples, TPA,
IPA, ISB, CHDM and EG represent a terephthalic acid, an isophthalic
acid, isosorbide (1,4:3,6-dianhydroglucitol),
1,4-cyclohexanedimethanol, and ethylene glycol respectively, and
the method for performance evaluation of polymers is as follows
[0020] (1) Intrinsic viscosity (IV): Measure the IV of the polymer
using Ubbelohde viscometer in a thermostat of 35.degree. C., after
dissolving the polymer in orthochlorophenol at 150.degree. C. by
the concentration of 0.12%
[0021] (2) Heat-resistance (Glass-rubber transition temperature
(Tg)): Measure the Tg of the polyester resin during 2.sup.nd
scanning with the temperature increasing speed of 10.degree.
C./min, after annealing the polyester resin at 300.degree. C. for 5
minutes and cooling to room temperature.
[0022] (3) Impact strength: Measure the izod impact strength of the
polyester resin test sample which is prepared with a thickness of
3.2 mm and notched according to ASTM D256, at 23.degree. C. using
an izod impact strength measuring instrument.
Comparative Example 1
Preparation of Polyester Resin
[0023] According to the amount described in Table 1, TPA, ISB and
EG were added in the reactor of 7 L volume, and the reactor was
heated to 240.about.300.degree. C. And a catalyst, a stabilizer, a
brightening agent and so on were added to carry out an
esterification reaction and a polycondensation reaction. And the
polymerization was terminated at certain viscosity. As described in
Table 1, in the finally polymerized polyester resin, the acid
component was TPA only, and the glycol components were 4 mol % of
ISB, 0 mol % of CHDM, 94 mol % of EG and 2 mol % DEG, the intrinsic
viscosity was 0.74 dl/g, the heat-resistance (Tg) was 85.degree.
C., and the izod impact strength according to ASTM D256 was 38
J/m.
Comparative Examples 2-5
Preparation of Polyester Resin
[0024] Except for using the amounts of TPA, IPA, ISB, and EG
according to Table 1, polyester resin was prepared by the same
manner described in Comparative Example 1. Intrinsic viscosity,
heat-resistance (Tg) and izod impact strength of the polyester
resin were measured, and represented in Table 1.
Examples 1-6
Preparation of Polyester Resin
[0025] Except for using the amounts of TPA, IPA, ISB, and EG
according to Table 1, polyester resin was prepared by the same
manner described in Comparative Example 1. Intrinsic viscosity,
heat-resistance (Tg) and izod impact strength of the polyester
resin were measured, and represented in Table 1.
TABLE-US-00001 TABLE 1 Examples Comparative Examples 1 2 3 4 5 6 1
2 3 4 5 TPA(%) 100 100 90 100 100 100 100 100 100 90 100 IPA(%) 10
10 ISB(%) 9 38 19 20 40 18 4 10 39 20 0 CHDM(%) 91 22 42 58 55 21 0
0 0 0 60 EG(%) 0 40 39 22 5 61 96 90 61 80 40 IV(dl/g) 0.66 0.59
0.63 0.69 0.55 0.70 0.74 0.65 0.58 0.63 0.75 Heat-resistance 92 123
104 107 130 102 85 93 124 104 85 (Tg, .degree. C.) Impact 90 68 129
N.B 302 91 38 37 30 32 N.B strength(J/m)
[0026] In Example 4 and Comparative Example 5, impact strength
could not be measured because any break did not occur (No-Break:
N.B) due to high mechanical strength. As shown in Table 1, to
compare a conventional polyester resin, the polyester resin
according to the present invention has much superior impact
strength though it has same or higher heat-resistance.
[0027] This application claims the priority benefit of Korean
Patent Application No. 10-2009-0086244 filed on Sep. 14, 2009. All
disclosure of the Korean Patent application is incorporated herein
by reference.
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