JP2002097263A - Production method for polyester - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a production method for a polyester, very excellent in processability, weathering resistance, transparency, moldability, flexibility and toughness, and preferably usable for various molding materials, thick sheet, fiber, film and paint. SOLUTION: This polyester is obtained by reacting dicarboxylic acids and glycols. The dicarboxylic acid contains one mol% or above of cyclohexanedicarboxylic acids, wherein the content of metal components is 1,000 ppm or below, and also the amount of impure particles having the maximum length of 4 μm or above is 30,000 pieces or below in 1g.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a novel polyester, and more particularly to a polyester having excellent weather resistance, transparency, moldability, flexibility, and toughness. This polyester can be suitably used for materials of plastic products such as various films and sheets, fibers, coating materials, paints and the like.

[0002]

2. Description of the Related Art Polyesters represented by polyethylene terephthalate have excellent physical and chemical properties and are therefore widely used as materials for plastic products such as various films and sheets, coating materials, paints and the like. On the other hand, polyesters containing a cyclohexanedicarboxylic acid component as a dicarboxylic acid component are known to be excellent in transparency, impact resistance, and the like as compared with ordinary polyethylene terephthalate, and can be suitably used for various molding materials. (JP-A-2000-44664, JP-A-5-2
No. 62860)

[0003]

The cyclohexanedicarboxylic acids can be obtained by hydrogenating benzenedicarboxylic acids. However, in this method, since a solid catalyst is usually used, the cyclohexanedicarboxylic acids formed are usually used. Cannot be directly removed from the reaction system in a solid state. Therefore, a method of dissolving cyclohexanedicarboxylic acids is used at or before and after the hydrogenation reaction.However, a polyester produced from the cyclohexanedicarboxylic acids thus obtained is used in the case of a molded article such as a thick plate. Films, paints and coating materials have drawbacks such as poor color tone and discoloration under the use environment, because of insufficient toughness and easy cracking. Also, when the application is a molded product such as a thick plate, whitening is apt to occur, in the case of a film, fish eyes and pinholes are generated, and in the case of a fiber, a yarn breakage occurs during spinning. There is.

That is, a polyester containing a cyclohexanedicarboxylic acid component obtained by a conventional method is much more excellent in processability, weather resistance, transparency, moldability, flexibility and toughness than ordinary polyethylene terephthalate. I couldn't say that. The object of the present invention, in view of the problems of the prior art, workability, weather resistance, transparency,
An object of the present invention is to provide a polyester which is extremely excellent in moldability, flexibility and toughness and which can be suitably used for various molding materials, slabs, fibers, films and paints, and a method for producing the same.

[0005]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to achieve the above-mentioned object, and as a result, the properties of polyester have been influenced by metal components and impurity particles contained in cyclohexanedicarboxylic acids as raw material monomers. And therefore, as cyclohexanedicarboxylic acids,
The metal component content is 1000 ppm or less, and 1 g
The number of impurity particles having a maximum length of 4 μm or more contained therein is 30
It has been found that polyesters having extremely high weather resistance, transparency, moldability, flexibility, and toughness can be produced by using 2,000 or less polyesters, and the present invention has been achieved. That is, the present invention provides a dicarboxylic acid containing 1 mol% or more of cyclohexanedicarboxylic acids having a metal component content of 1000 ppm or less and having a maximum number of impurity particles having a maximum length of 4 μm or more in 1 g of 30,000 or less,
A method for producing a polyester, which comprises reacting a glycol with a glycol.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The cyclohexanedicarboxylic acids used as raw materials in the present invention include 1,1-,
Examples thereof include 1,2-, 1,3-, and 1,4-cyclohexanedicarboxylic acids, esters thereof such as dimethyl ester and diethyl ester, and acid anhydrides such as 1,2-cyclohexanedicarboxylic anhydride. These compounds include 1,2-, 1,3-, and 1,4-benzenedicarboxylic acids, esters thereof such as dimethyl ester and diethyl ester, and acid anhydrides such as 1,2-benzenedicarboxylic anhydride. And the like by hydrogenating benzenedicarboxylic acids. Some of these compounds may have cis- and trans-isomers, but in the present invention, either one of them may be used, or a mixture of isomers having various ratios may be used. . The amount of the cyclohexanedicarboxylic acid used can be selected in a range where the cyclohexanedicarboxylic acid component in all dicarboxylic acid components constituting the polymer is 1 mol% or more.

The cyclohexanedicarboxylic acids used in the present invention have a metal component content of 1000 ppm.
Or less, preferably 500 ppm or less, and the number of impurity particles having a maximum length of 4 μm or more contained in 1 g is 300 or less.
No more than 00, preferably no more than 10,000 can be used. The metal component content exceeds 1000 ppm,
When the number of the impurity particles exceeds 30,000, problems such as poor processability, insufficient toughness and insufficient flexibility, poor transparency, poor color tone, and discoloration occur in polyesters made from these. The impurity particles referred to here are impurity particles floating or settling in a solid state in a liquid obtained by melting or dissolving cyclohexanedicarboxylic acids in a solvent.

In order to eliminate these problems, a method of removing impurities and metal components by performing high-precision filtration with a filter in the process of producing polyester has been proposed. However, impurities such as impurities contained in cyclohexanedicarboxylic acids and the like may be removed. When the amount of the metal component is large, there is a problem that the life of the filter is significantly shortened, the productivity is impaired, and the production cost is increased.

According to the study of the present inventors, cyclohexanedicarboxylic acid satisfying this essential requirement can be produced by the following method. Cyclohexanedicarboxylic acids can be obtained by hydrogenating benzenedicarboxylic acids. As a hydrogenation catalyst, a transition metal belonging to Groups 8, 9, and 10 of the periodic table such as palladium, ruthenium, and platinum can be used as a simple metal or activated carbon. A solid catalyst dispersed on a carrier such as alumina is used. With these catalysts,
The feed can be converted almost quantitatively. At or before and after the hydrogenation reaction, cyclohexanedicarboxylic acids are dissolved in a solvent having a sufficiently low metal content at an appropriate concentration and temperature. Water is preferred as the solvent, but other solvents that do not inhibit the hydrogenation reaction and have appropriate solubility may be used. Next, by subjecting the mixture after the reaction to solid-liquid separation, a solution of cyclohexanedicarboxylic acids from which impurity particles and metal components derived from the catalyst and the like have been sufficiently removed can be obtained. Filtration is preferred as the solid-liquid separation method from the viewpoint of sufficiently removing fine solids. As the filtration device, a Nutsche filter, a Funda filter, a leaf filter, a candle filter, a cartridge filter, and the like, which are suitable for filtration under a pressurized condition, are preferable. Further, a filter cloth, a wire mesh, a sintered metal, a carbon filter, or the like is suitably used as the filter medium. In carrying out the filtration, by installing a plurality of filtration devices in which the openings are sequentially reduced to be small, it is possible to sufficiently remove impurity particles having a very small particle size while using a filtration device having a size that can be industrially implemented. It can be removed. The solution obtained by the solid-liquid separation is subjected to crystallization, distillation, and other steps to separate and purify the solvent, whereby cyclohexanedicarboxylic acids having a quality usable in the present invention can be obtained.

In the present invention, the cyclohexanedicarboxylic acid component in all the dicarboxylic acid components constituting the polymer is within the above-mentioned range, and all dicarboxylic acids that can be used as a raw material of the polyester are used in order to enhance physical properties such as heat resistance. Can be used. As this dicarboxylic acid, an ordinary polymer grade one is suitably used. Specifically, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, isophthalic acid, phthalic acid, terephthalic acid, 2-methylterephthalic acid, naphthalenedicarboxylic acid, Biphenyl dicarboxylic acid, decalin dicarboxylic acid,
Tetralin dicarboxylic acid, norbornane dicarboxylic acid,
Tricyclodecane dicarboxylic acid, pentacyclododecane dicarboxylic acid, isophorone dicarboxylic acid and the like,
One or more of these can be used.

The glycols used in the present invention include:
All glycols that can be used as raw materials for polyester can be used. As the glycol, a usual polymer grade is preferably used. Specifically, ethylene glycol, trimethylene glycol,
1,4-butanediol, 1,5-pentanediol,
Aliphatic diols such as 1,6-hexanediol, diethylene glycol, propylene glycol, neopentyl glycol; polyether compounds such as polyethylene glycol, polypropylene glycol, polybutylene glycol; 1,3-cyclohexanedimethanol;
1,4-cyclohexanedimethanol, 1,2-decahydronaphthalenedimethanol, 1,3-decahydronaphthalenedimethanol, 1,4-decahydronaphthalenedimethanol, 1,5-decahydronaphthalenedimethanol, 1, 6-decahydronaphthalenedimethanol, 2,
Alicyclic diols such as 7-decahydronaphthalenedimethanol, tetralin dimethanol, norbornane dimethanol, tricyclodecane dimethanol, and pentacyclododecane dimethanol; 4,4 '-(1-methylethylidene) bisphenol, methylenebisphenol (Bisphenol F), alkylene oxide adducts of bisphenols such as 4,4'-cyclohexylidenebisphenol (bisphenol Z) and 4,4'-sulfonylbisphenol (bisphenol S); hydroquinone, resorcinol, 4,4'-dihydroxy Biphenyl, 4,4 '
Alkylene oxide adducts of aromatic dihydroxy compounds such as -dihydroxydiphenyl ether and 4,4'-dihydroxydiphenylbenzophenone, and one or more of these can be used.

The above cyclohexanedicarboxylic acids are
The polyester of the present invention is produced by reacting a dicarboxylic acid containing at least mol% with a glycol.

The method for producing the polyester of the present invention is characterized in that the metal component content of cyclohexanedicarboxylic acids is 1,000 ppm or less and the number of impurity particles having a maximum length of 4 μm or more contained in 1 g is 30000 or less. There is no particular limitation other than the above, and a conventionally known polycondensation method can be applied. For example, a melt polymerization method such as a transesterification method and a direct esterification method or a solution polymerization method can be used. Conventionally known transesterification catalysts, esterification catalysts, etherification inhibitors, polymerization catalysts used for polymerization, various stabilizers such as heat stabilizers and light stabilizers, and polymerization regulators can also be used. Examples of the transesterification catalyst include compounds such as manganese, cobalt, zinc, titanium, and calcium. Examples of the esterification catalyst include compounds such as manganese, cobalt, zinc, titanium, and calcium. Examples of the esterification catalyst include amine compounds. . Examples of the polycondensation catalyst include compounds such as germanium, antimony, tin, and titanium. It is also effective to add various phosphorus compounds such as phosphoric acid, phosphorous acid and phenylphosphonic acid as heat stabilizers. In addition, a light stabilizer, an antistatic agent, a lubricant, an antioxidant, a release agent and the like may be added. In the direct esterification method, water may be added to improve the slurry properties. The polyester of the present invention is less susceptible to whitening during molding than the conventional polyester,
Fisheye and pinholes are less likely to occur during film formation. In addition, problems such as yarn breakage during spinning hardly occur and the processability is excellent. Further, since it has excellent transparency, toughness, and flexibility, it can be suitably used for various molding materials, thick plates, films, and fibers. Furthermore, it is excellent in weather resistance, and can be suitably used for coating materials and paints with extremely little discoloration and deterioration under the use environment.

[0014]

The present invention will be described in detail with reference to the following examples, but the present invention is not limited to these examples.

Example 1 55.3 kg (334 mol) of terephthalic acid, 3.0 kg of 10% palladium-supported activated carbon, and 470.5 kg of water were charged into an autoclave equipped with a stirrer having a capacity of 600 liters and a heating / cooling jacket, and replaced with hydrogen gas. After that, the pressure was increased to 3.0 MPa gauge by blowing hydrogen gas, and the temperature was increased to 180 ° C. over 2 hours. Reaction pressure is 3.0
Stirring was continued for 4 hours while supplying hydrogen gas so as to maintain the MPa gauge, and a hydrogenation reaction was performed. During this time, the temperature rose to 195 ° C. due to the heat of reaction. 9 in the autoclave
After cooling to 0 ° C., the reaction mixture was filtered through a Nutsche filter to remove solids. The obtained filtrate was scraped, transferred to a crystallization tank equipped with blades, cooled to 15 ° C., crystallized, and then subjected to solid-liquid separation with a glass filter. The obtained cake was rinsed with 40 kg of cold water at 15 ° C., and then dried to obtain 1,4-cyclohexanedicarboxylic acid.
8 kg were obtained. The 1,4-cyclohexanedicarboxylic acid had a cis / trans ratio of 60/40, contained 8,400 impurity particles having a maximum length of 4 μm or more, and contained 220 ppm of a metal component. 17. 1,4-cyclohexanedicarboxylic acid thus obtained;
2 kg (0.10 kmol), terephthalic acid 149.2
kg (0.90 kmol), ethylene glycol
1 kg (1.00 kmol), manganese acetate tetrahydrate 0.03 mol% / acid, triethylamine 0.0
1 mol% / acid was charged into a reaction vessel, and the atmosphere was replaced with vacuum nitrogen three times. Then, the temperature was raised to 200 ° C. in a nitrogen atmosphere to start an initial condensation reaction. Thereafter, a predetermined amount of water was distilled off by elevating the temperature to 220 ° C. and introducing nitrogen to complete the initial condensation reaction. The initial condensation reaction time was 4 hours. 220 ° C
Then, 0.05 mol% / acid of germanium oxide and 0.01 mol% / acid of triphenyl phosphite were added, and the temperature was raised to 240 ° C. After reaching 240 ° C., the temperature was raised to 280 ° C. and the pressure was simultaneously reduced to start the polycondensation reaction. The temperature reached 280 ° C. in 2 hours from the start of the polycondensation reaction, and the polycondensation reaction was further continued for 2 hours after the degree of vacuum was set to 2 torr or less. The obtained prepolymer was taken out of the reactor and cooled with water. The prepolymer was charged into a solid phase polymerization apparatus, and after predrying, solid phase polymerization was performed at 210 ° C. for 24 hours to obtain a polyester chip. The limiting viscosity of this polyester was 1.05 dl / g. Next, this polyester chip was JIS K-7152.
Injection molding was performed under the conditions of cylinder temperature 271 ° C. and total cycle time 43 seconds in accordance with JIS K-713.
A multipurpose test piece A type specified in 9 was obtained. The obtained test piece was transparent and no whitening was observed. JIS K
As a result of performing a tensile test in accordance with the regulation of −7162, the tensile fracture stress was 63.7 MPa.

Example 2 54.8 kg (330 mol) of isophthalic acid, 3.0 kg of 10% palladium-supported activated carbon and 270.3 kg of water were charged into an autoclave equipped with a stirrer having a capacity of 600 liters and a heating / cooling jacket, and replaced with hydrogen gas. After that, the pressure was increased to 3.0 MPa gauge by blowing hydrogen gas, and the temperature was increased to 180 ° C. over 2 hours. Reaction pressure is 3.0
Stirring was continued for 3 hours while supplying hydrogen gas so as to maintain the MPa gauge, and a hydrogenation reaction was performed. During this time, the temperature rose to 205 ° C. due to the heat of reaction. 9 in the autoclave
After cooling to 0 ° C., the reaction mixture was filtered through a Nutsche filter to remove solids. The obtained filtrate was scraped, transferred to a crystallization tank equipped with blades, cooled to 15 ° C., crystallized, and then subjected to solid-liquid separation with a glass filter. The obtained cake was rinsed with 40 kg of cold water at 15 ° C., and then dried, and 1,3-cyclohexanedicarboxylic acid.
6 kg were obtained. This 1,3-cyclohexanedicarboxylic acid had a cis / trans ratio of 45/55, contained 7,200 impurity particles / g having a maximum length of 4 μm or more, and had a metal component content of 280 ppm. 8.6 of the thus obtained 1,3-cyclohexanedicarboxylic acid
kg (0.05kmol), terephthalic acid 156.1k
g (0.95 kmol), ethylene glycol 62.0
kg (1.00 kmol), manganese acetate tetrahydrate 0.
03 mol% / acid, triethylamine 0.01 m
ol% / acid in a reaction vessel and purging with vacuum nitrogen
After the first cycle, the temperature was raised to 200 ° C. in a nitrogen atmosphere to start an initial condensation reaction. Thereafter, a predetermined amount of water was distilled off by elevating the temperature to 220 ° C. and introducing nitrogen to complete the initial condensation reaction.
The initial condensation reaction time was 4 hours. At 220 ° C., 0.05 mol% of germanium oxide / acid and 0.01 mol% of triphenyl phosphite / acid were added and 2
The temperature was raised to 40 ° C. After reaching 240 ° C., the temperature was raised to 280 ° C. and the pressure was simultaneously reduced to start the polycondensation reaction. The temperature reached 280 ° C. in 2 hours from the start of the polycondensation reaction, and the polycondensation reaction was further continued for 2 hours after the degree of reduced pressure was set to 2 torr or less. The obtained prepolymer was taken out of the reactor and cooled with water. Charge the prepolymer into the solid state polymerization device,
After pre-drying, solid phase polymerization was performed at 210 ° C. for 24 hours,
Polyester chips were obtained. The intrinsic viscosity of this polyester was 1.09 dl / g. Next, this polyester chip was JIS K-7152.
Injection molding was performed under the conditions of cylinder temperature of 275 ° C. and a total cycle time of 45 seconds in accordance with JIS K-713.
A multipurpose test piece A type specified in 9 was obtained. The obtained test piece was transparent and no whitening was observed. JIS K
As a result of performing a tensile test in accordance with the regulation of −7162, the tensile fracture stress was 58.3 MPa.

COMPARATIVE EXAMPLE 1 55.5 kg (334 mol) of terephthalic acid, 3.0 kg of 10% palladium-supported activated carbon and 475.1 kg of water were charged into an autoclave equipped with a stirrer having a capacity of 600 liters and a heating / cooling jacket, and replaced with hydrogen gas. After that, the pressure was increased to 3.0 MPa gauge by blowing hydrogen gas, and the temperature was increased to 180 ° C. over 2 hours. Reaction pressure is 3.0
Stirring was continued for 4 hours while supplying hydrogen gas so as to maintain the MPa gauge, and a hydrogenation reaction was performed. During this time, the temperature rose to 195 ° C. due to the heat of reaction. 9 in the autoclave
After cooling to 0 ° C., the reaction mixture was withdrawn into an open container and decanted for 10 minutes. 2 supernatants
33 kg was collected and transferred to a crystallization tank with scraping blades.
After cooling to ℃ for crystallization, solid-liquid separation was performed using a glass filter. The obtained cake is cooled at 15 ° C in cold water 20k.
g, and then dried to obtain 22.9 kg of 1,4-cyclohexanedicarboxylic acid. This 1,4-cyclohexanedicarboxylic acid has a cis / trans ratio of 60/4.
0, the number of contained impurity particles having a maximum length of 4 μm or more was 52000 particles / g, and the content of the metal component was 380.
ppm. 16.9 kg (0.10 kmol) of the thus obtained 1,4-cyclohexanedicarboxylic acid,
147.7 kg (0.90 kmol) of terephthalic acid, 62.3 kg (1.00 kmol) of ethylene glycol,
A reaction vessel was charged with 0.03 mol% / acid of manganese acetate tetrahydrate and 0.01 mol% / acid of triethylamine, and after performing vacuum nitrogen replacement three times, the temperature was raised to 200 ° C. in a nitrogen atmosphere to perform an initial condensation reaction. Started. Then 2
A predetermined amount of water was distilled off by elevating the temperature to 20 ° C. and introducing nitrogen to complete the initial condensation reaction. The initial condensation reaction time was 4 hours. Germanium oxide 0.05mo at 220 ℃
l% / acid and triphenyl phosphite 0.01m
ol% / acid was added and the temperature was raised to 240 ° C. 240 ° C
, The temperature was raised to 280 ° C. and the pressure was simultaneously reduced to start the polycondensation reaction. 2 hours after the start of polycondensation reaction
When the temperature reaches 80 ° C and the degree of pressure reduction is 2 torr or less,
The polycondensation reaction was continued for another 2 hours. The obtained prepolymer was taken out of the reactor and cooled with water. The prepolymer is charged into a solid-state polymerization apparatus, and after pre-drying, is heated at 210 ° C. for 24 hours.
Solid phase polymerization was performed for a time to obtain a polyester chip. The limiting viscosity of this polyester was 1.07 dl / g. Next, this polyester chip was JIS K-7152.
Injection molding was carried out under the conditions of cylinder temperature 272 ° C. and total cycle time 43 seconds according to JIS K-713.
A multipurpose test piece A type specified in 9 was obtained. The obtained test piece was partially whitened. JIS K-7162
As a result of conducting a tensile test in accordance with the rules of the above, the tensile fracture stress was 47.1 MPa.

Comparative Example 2 55.0 kg (331 mol) of isophthalic acid was 5 wt%
The resultant was dissolved in 300 kg of an aqueous sodium hydroxide solution, and charged together with 3.0 kg of activated carbon supported with 10% palladium in an autoclave equipped with a stirrer having a capacity of 600 liters and a heating / cooling jacket. Thereafter, the pressure was increased to 3.0 MPa gauge by blowing hydrogen gas, and the temperature was increased to 180 ° C. over 2 hours. Stirring was continued for 3 hours while supplying hydrogen gas so that the reaction pressure maintained a 3.0 MPa gauge, thereby performing a hydrogenation reaction. During this time, the temperature rose to 200 ° C. due to the heat of reaction. After cooling to 50 ° C. in an autoclave, the reaction mixture was filtered through a Nutsche filter to remove solids. Dilute hydrochloric acid was added to the obtained filtrate, and after performing acid precipitation, solid-liquid separation was performed using a glass filter. The obtained cake was rinsed twice with 40 kg of cold water at 15 ° C., and dried, and 42.3 kg of 1,3-cyclohexanedicarboxylic acid was dried.
I got This 1,3-cyclohexanedicarboxylic acid has a cis / trans ratio of 40/60 and a maximum length of 4
The number of impurity particles having a size of μm or more was 6,500 / g, and the content of the metal component was 1,720 ppm. 8.5 kg of the thus obtained 1,3-cyclohexanedicarboxylic acid
(0.05 kmol), terephthalic acid 155.9 kg
(0.95 kmol), ethylene glycol 62.0 k
g (1.00 kmol), manganese acetate tetrahydrate 0.0
3mol% / acid, triethylamine 0.01mo
After 1% / acid was charged into a reaction vessel and the atmosphere was replaced with vacuum nitrogen three times, the temperature was raised to 200 ° C. in a nitrogen atmosphere to start an initial condensation reaction. Thereafter, a predetermined amount of water was distilled off by elevating the temperature to 220 ° C. and introducing nitrogen to complete the initial condensation reaction. The initial condensation reaction time was 4 hours. At 220 ° C., 0.05 mol% / acid of germanium oxide and 0.01 mol% / acid of triphenyl phosphite were added and added.
The temperature was raised to 0 ° C. After reaching 240 ° C., the temperature was raised to 280 ° C. and the pressure was simultaneously reduced to start the polycondensation reaction. The temperature reached 280 ° C in 2 hours from the start of the polycondensation reaction, and the degree of pressure reduction was 2
After setting the pressure to torr or less, the polycondensation reaction was continued for another 2 hours. Pull out the obtained prepolymer from the reaction vessel,
Water cooled. The prepolymer was charged into a solid phase polymerization apparatus, and after predrying, solid phase polymerization was performed at 210 ° C. for 24 hours to obtain a polyester chip. The limiting viscosity of this polyester was 1.11 dl / g. Next, this polyester chip was JIS K-7152.
Injection molding was performed under the conditions of cylinder temperature of 278 ° C. and a total cycle time of 45 seconds in accordance with JIS K-713.
A multipurpose test piece A type specified in 9 was obtained. The obtained test piece was entirely white and cloudy. As a result of performing a tensile test according to the provisions of JIS K-7162, the tensile fracture stress was 32.6 MPa.

[0019]

The polyester of the present invention is a polyester excellent in weather resistance, transparency, moldability, flexibility and toughness, and is a molded article or fiber such as a film, a sheet or a container, a coating material and a paint. It can be suitably used for example.

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Claims (1)

[Claims] 1. A dicarboxylic acid containing 1 mol% or more of cyclohexanedicarboxylic acid having a metal component content of 1,000 ppm or less and containing not more than 30,000 impurity particles having a maximum length of 4 μm or more in 1 g, and glycol. A method for producing a polyester, characterized by reacting a polyester.