Abstract: A container includes an outer layer defining an exterior surface and including poly (ethylene terephthalate) and an inner barrier layer including semi-crystalline poly(ethylene furanoate) including semi-crystalline poly(ethylene furanoate) where the poly(ethylene furanoate) has a crystallinity Xc of 3 to 40%.

Abstract: The present invention relates to a resin composition comprising 40% to 50% by weight of a polyester resin on the basis of a total of 100% by weight of the composition, the polyester resin comprising a main resin and an auxiliary resin, wherein the main resin has a higher molecular weight than the auxiliary resin, and the difference of a glass transition temperature between the main resin and the auxiliary resin is 25° C. or less.

Abstract: This disclosure provides effective methods for expanding the processing window for poly(ethylene furanoate) (PEF) and poly(ethylene furanoate) co-polymer (PEF co-polymer) polyester preforms, such that these preforms can be beneficially used in the fabrication of bottles and containers, including bottles for carbonated soft drinks. The processing window is expanded by, for example, pre-conditioning the PEF or PEF co-polymer preform prior to stretch blow-molding by contacting the PEF or PEF co-polymer preform with water or high (>50%) relative humidity air for a desired time period and at a temperature greater than or equal to ambient temperature, to take advantage of the unique and unexpected properties afforded the preform by water sorption at these temperatures.

Abstract: A polyester including poly(ethylene 2,5-furandicarboxylate is prepared by esterification of a starting mixture including 2,5-furandicarboxylic acid and ethylene glycol to form an ester composition, and by subjecting the ester composition thus obtained to polycondensation at reduced pressure in the presence of a polycondensation catalyst to obtain a polycondensate. The mixture is reacted under conditions such that the esterification potential as defined by Esterification Potential (EsPo)=(MR?1)2*PH2O(T), where MR represents the molar ratio of ethylene glycol over 2,5-furandicarboxylic acid, MR being greater than 1; PH2O(T) represents the pure component vapor pressure (in bar) of water at temperature T, which is the final reaction temperature in the esterification mixture before the pressure is reduced to effect the polycondensation, is less than 0.8.

Abstract: The present invention relates to a modified polymeric material. The modified polymeric material includes a polymer having a modified surface, where the modified surface includes nano, micron, and/or submicron scale features. The present invention also relates to an implant comprising the modified polymeric material. The present invention further relates to processes for making the modified polymeric material and the implant.

Abstract: The present invention is directed to a heat-resistant polyester blow-molded article made of a polyester resin composition containing 0.035 to 1.75 equivalent/ton of a hindered phenol structural unit and containing at least one selected from the group consisting of antimony compounds as a polymerization catalyst, the cyclic trimer content thereof being less than or equal to 0.5% by mass, the acetaldehyde content thereof being less than or equal to 50 ppm and the intrinsic viscosity thereof being 0.68 to 0.90 dL/g. The present invention enables efficient production of a molded article excellent in transparency and heat-resistant dimensional stability, in particular a heat-resistant blow-molded article. Moreover, according to the present invention, there are provided a polyester resin composition which is excellent in long-term continuous moldability and hardly stains a mold and a molded article prepared therewith, and a method for molding a polyester blow-molded article using the polyester resin composition.

Abstract: Provided is a composition with partially aromatic polyester polymers having an It.V. of at least 0.50 dL/g, produced in an ester exchange melt phase process, having from zero or greater than zero to less than 5 ppm titanium, from zero or greater than zero to less then 10 ppm germanium, and from zero or greater than zero to less than 20 ppm manganese.

Abstract: The invention relates to a process for making polyethylene terephthalate (PET) from ethylene glycol (EG), purified terephthalic acid (PTA) and optionally up to 6 mol % comonomer, using a mixed metal catalyst system and comprising the steps of a) esterifying EG and PTA to form diethyleneglycol terephthalate and oligomers (DGT), and b) melt-phase polycondensing DGT to form PET and EG, wherein the catalyst system substantially consists of 70-160 ppm of Sb-compound, 20-70 ppm of Zn-compound, and 0.5-20 ppm of Ti-glycolate as active components (ppm metal based on PET). With this process that applies reduced amount of metal catalyst components PET can be obtained with high productivity, which polyester shows favorable color and optical clarity, also if recycling of EG is applied within the process.

Abstract: A process for preparing a polymer having a 2,5-furandicarboxylate moiety within the polymer backbone, and having a number average molecular weight of at least 25,000, includes a transesterification step, a polycondensation step, a drying and/or crystallizing step, and a step where the polymer is subjected to post condensation conditions, and to a polyester-containing bottle or film or fibre-containing woven or non-woven object made from melt-processing poly(ethylene-2,5-furandicarboxylate), where the poly(ethylene-2,5-furandicarboxylate) is obtainable by the process of the invention.

Abstract: The invention relates to a process for making polyethylene terephthalate (PET) from ethylene glycol (EG), purified terephthalic acid (PTA) and optionally up to 30 mol % comonomer, using a catalyst system essentially consisting of antimony—(Sb), zinc—(Zn) and phosphorous—(P) compounds, comprising the steps of a) esterifying EG and PTA to form diethyleneglycol terephthalate and oligomers (DGT), and b) melt-phase polycondensing DGT to form polyester and EG1 wherein the Sb- and P-compounds are added in step a) and the Zn-compound is added after step a). With this process PET can be obtained that shows favorable color and optical clarity, also if recycling of EG is applied in the process, and a relatively low rate of acetaldehyde regeneration during melt-processing.

Abstract: A method for the production of solid polyester polymer particles comprising: a) polycondensing a molten polyester polymer composition in the presence of a polycondensation catalyst composition comprising antimony species; b) continuing the polycondensation of the molten polyester polymer composition to an It.V. of 0.68 dL/g or more; and c) after reaching an It.V. of 0.68 dL/g or more, adding a catalyst stabilizer or deactivator to the polymer melt; and d) after reaching an It.V. of 0.68 dL/g or more, solidifying the melt into solid polyester polymer particles which do not contain organic acetaldehyde scavengers. In a further embodiment, after solidification of the polyester from the melt phase polycondensation process: e) the amount of residual acetaldehyde in the particles in the solid state is reduced to a level of 10 ppm or less without increasing the It.V. of the particles by more than 0.03 dL/g.

Abstract: A process for removing metal species from a composition comprising contacting: a. an oligomer mixture stream comprising the monomers of a partially aromatic polyester polymer and at least one metal species, or b. a molten polyester polymer stream comprising partially aromatic polyester polymers and at least one metal species, with a non-catalytic porous material in the presence of hydrogen to produce a treated stream containing a reduced amount of at least one metal species. There are provided compositions comprising a partially aromatic polyester polymer having an It.V. of at least 0.50 produced in a direct esterification melt phase process, from greater than 0 to less than 50 ppm antimony, and less than 40 ppm cobalt, or produced in an ester exchange melt phase process, having from greater than zero to less than 5 ppm titanium and less than 10 ppm manganese.

Abstract: Polyesters described herein are prepared in whole or in part from biomass. In one aspect, a copolyester is formed from monomers of 2,5-furan dicarboxylic acid, or a lower alkyl ester thereof, at least one aliphatic or cycloaliphatic C3-C10 diol, and terephthalic acid. In another aspect, a polyester is formed from monomers of 2,5-furan dicarboxylic acid, or a lower alkyl ester thereof, and isosorbide. In some aspects, the polyester is polyethylene isosorbide furandicarboxylate, poly(2,5-furandimethylene adipate), or polyvanillic ester. The polyesters may have desirable physical and thermal properties and can be used to partially or wholly replace polyesters derived from fossil resources, such as poly(ethylene terephthalate).

Abstract: A poly(lactic acid) resin composition is provided, comprising (a) a poly(lactic acid) resin, (b) at least one modifier selected from at least one metal/nonmetal alkoxide, at least one metal/nonmetal alkoxide having at least one functional group capable of reacting with the poly(lactic acid) resin, or a mixture thereof, (c) a first catalyst, and (d) optionally, a second catalyst. A process for preparing a transparent and impact-resistant article from the poly(lactic acid) resin composition of the invention, and articles prepared therefrom are also provided.

Abstract: A melt phase process for making a polyester polymer melt phase product by adding an antimony containing catalyst to the melt phase, polycondensing the melt containing said catalyst in the melt phase until the It.V. of the melt reaches at least 0.75 dL/g. Polyester polymer melt phase pellets containing antimony residues and having an It.V. of at least 0.75 dL/g are obtained without solid state polymerization. The polyester polymer pellets containing antimony residues and having an It.V. of at least 0.70 dL/g obtained without increasing the molecular weight of the melt phase product by solid state polymerization are fed to an extruder, melted to produce a molten polyester polymer, and extruded through a die to form shaped articles. The melt phase products and articles made thereby have low b* color and/or high L* brightness, and the reaction time to make the melt phase products is short.

Abstract: The present invention provides processes for producing polyester. In one of the embodiments, the invention provides a process for producing polyester, comprising adding a catalyst in a polycondensation reaction, esterification reaction or transesterification reaction between components comprising at least a polyfunctional alcohol and at least a polyfunctional carboxylic acid or ester-forming derivative of a polyfunctional carboxylic acid to produce the polyester; and obtaining the polyester, wherein the polymerization catalyst comprises an aluminum substance and a phosphorus compound, wherein the aluminum substance is selected from the group consisting of aluminum hydroxide and aluminum alkoxides, and wherein the phosphorus compound has an aromatic ring structure.

Abstract: The present invention relates to a method for the continuous production of high-molecular polyesters by esterification of dicarboxylic acids and/or transesterification of dicarboxylic acid esters with diols and/or mixtures thereof in the presence of catalysts with formation of a prepolymer in a tower reactor and polycondensation thereof to form a high-molecular polyester in a polycondensation reactor, a prepolymer with >40 to 70 repeat units (DP) being produced in the tower reactor and this prepolymer being polycondensed in only one further reactor to form a polyester with >150 to 205 DP.

Abstract: The present invention relates to a method for the continuous production of high-molecular polyesters by esterification of dicarboxylic acids and/or transesterification of dicarboxylic acid esters with diols and/or mixtures thereof in the presence of catalysts with formation of a prepolymer in a tower reactor and polycondensation thereof to form a high-molecular polyester in a polycondensation reactor, a prepolymer with >40 to 70 repeat units (DP) being produced in the tower reactor and this prepolymer being polycondensed in only one further reactor to form a polyester with >150 to 205 DP.

Abstract: A melt phase process for making a polyester polymer melt phase product by adding an antimony containing catalyst to the melt phase, polycondensing the melt containing said catalyst in the melt phase until the It.V. of the melt reaches at least 0.75 dL/g. Polyester polymer melt phase pellets containing antimony residues and having an It.V. of at least 0.75 dL/g are obtained without solid state polymerization. The polyester polymer pellets containing antimony residues and having an It.V. of at least 0.70 dL/g obtained without increasing the molecular weight of the melt phase product by solid state polymerization are fed to an extruder, melted to produce a molten polyester polymer, and extruded through a die to form shaped articles. The melt phase products and articles made thereby have low b* color and/or high L* brightness, and the reaction time to make the melt phase products is short.

Abstract: An aromatic polyester resin composition, including: a melt-kneaded product of 99-70 wt. parts of an aromatic polyester resin and 1-30 wt. parts (providing a total of 100 wt. parts together with the aromatic polyester resin) of a polyglycolic acid resin, wherein the aromatic polyester resin is an aromatic polyester resin polymerized with a germanium compound (catalyst), and the polyglycolic acid resin is a polyglycolic acid resin obtained by ring-opening polymerization of glycolide. As a result, gas generation during the melt-processing of a composition obtained by adding a relatively small amount of polyglycolic acid resin to an aromatic polyester resin is effectively suppressed to provide an aromatic polyester resin composition with a good gas-barrier property.

Abstract: A biaxially oriented polyester film for solar cells which is made of a composition of a polyethylene terephthalate prepared by using an antimony compound and/or a titanium compound as a polycondensation catalyst(s), wherein the composition contains 10 to 80 mmol % of a phosphorus atom derived from specific phosphonic acid or specific phosphinic acid and 2 to 60 mmol % of the total of an antimony atom and/or a titanium atom as metal atoms based on the number of moles of all dicarboxylic acid components constituting the polyethylene terephthalate, the biaxially oriented polyester film has a plane orientation coefficient “fn” of 0.160 to 0.175, and the polyester of the film has an intrinsic viscosity number of 0.56 to 0.74 dl/g and a terminal carboxyl group concentration of 6 to 29 equivalents/ton.

Abstract: Disclosed herein are a nanocrystal-polydimethylsiloxane composite and a method for preparing the same. More specifically, provided are a nanocrystal-polydimethylsiloxane composite in which one or more polydimethylsiloxane derivatives having urea cross-links are bound to the surface of a nanocrystal, and a method for preparing the same. The nanocrystal-polydimethylsiloxane composite comprises optically transparent polydimethylsiloxane with remarkably high durability, thus imparting improved luminescence efficiency and product reliability to various electronic devices, when applied as a luminescent material to the electronic devices.

Abstract: A polymer containing a polyester polymer unit having the formula -(I-III-II)-, wherein III is derived form a di-carboxylic acid, wherein I is derived from 1,3 cyclohexanedimethanol, wherein II is derived from 1,4 cyclohexanedimethanol and wherein the polymer is a solid at room temperature.

Abstract: The present invention relates to a process for preparing polyethylene naphthalate, comprising the steps of: esterifying 2,6-naphthalene dicarboxylic acid and ethylene glycol, or glycols using the two materials as major material to obtain prepolymer which comprises bis(beta-hydroxyethyl)naphthalate or low polymer as main material; and performing polycondensation reaction to thereby prepare polyethylene naphthalate. The process of the present invention has advantages of: enabling esterification with a low molar ratio of ethylene glycol to reduce reaction time, thereby increasing process efficiency; minimizing formation of side reaction products to improve properties; and preventing deterioration of the products by performing polycondensation at a low temperature to thereby obtain polyethylene naphthalate polymers of high quality.

Abstract: A melt phase process for making a polyester polymer melt phase product by adding an antimony containing catalyst to the melt phase, polycondensing the melt containing said catalyst in the melt phase until the It.V. of the melt reaches at least 0.75 dL/g. Polyester polymer melt phase pellets containing antimony residues and having an It.V. of at least 0.75 dL/g are obtained without solid state polymerization. The polyester polymer pellets containing antimony residues and having an It.V. of at least 0.70 dL/g obtained without increasing the molecular weight of the melt phase product by solid state polymerization are fed to an extruder, melted to produce a molten polyester polymer, and extruded through a die to form shaped articles. The melt phase products and articles made thereby have low b* color and/or high L* brightness, and the reaction time to make the melt phase products is short.

Abstract: A process comprises heating at a first temperature under an inert atmosphere and at a first pressure of at least 101 kPa a cyclohexanedimethanol, and a polyethylene terephthalate component selected from the group consisting of polyethylene terephthalate and polyethylene terephthalate copolymers, to form a molten mixture; and heating the molten mixture with agitation at a second temperature higher than the first temperature and a second, subatmospheric pressure for a time and under conditions effective to form a modified polycyclohexane dimethylene terephthalate copolymer comprising at least one residue derived from the polyethylene terephthalate component.

Abstract: Triptycene derivatives and method for preparing the same are provided. The triptycene derivatives may be triptycene di-ester of the formula (I) or triptycene di-acid of the formula (II): where n=1-5.

Abstract: A polyester composition produced without using an antimony compound as a polycondensation catalyst and including (I) composition containing, on a weight basis, 30 ppm or less of antimony, 0.5 to 50 ppm of titanium, and 0.1 to 100 ppm of phosphorus, in which the number density of titanium-containing particles, the equivalent circular diameter of which is 1?m or more, is less than 100/0.02 mg; and (II) a composition containing, on a weight basis, antimony, titanium and phosphorous as defined above, in which organic polymer particles are contained in amount of 0.1 to 5 wt%, the organic polymer particles having an average particle diameter determined by dynamic light scattering of 0.05 to 3?m and containing 0.01% or less of coarse particles relative to the total number of the particles, the coarse particles having a diameter at least twice the average particle diameter.

Abstract: A polyester resin that can be beneficially employed as one finding application in deactivation of polycondensation catalysts for polyester production and suppression of forming of acetaldehyde and other aldehydes and cyclic ester oligomers at molding stage. In particular, there is provided a polyester resin composed mainly of an aromatic dicarboxylic acid component and a glycol component wherein a phosphorus compound is incorporated through copolymerization or blending in an amount of 100 to 10,000 ppm in terms of phosphorus element, characterized in that the contents of Zn element, Fe element, Ni element and Cr element are not greater than specified values.

Abstract: The present invention relates to a PET resin and a process for producing polyethylene terephthalate (PET) resin having conventional catalysts such as antimony, titanium, tin or germanium compounds and a glycol insoluble tungsten compound or tungsten trioxide or tungsten carbide as co-catalyst. The tungsten compound as a co catalyst increases the rates of solid state polymerization and improves the ‘L’ color value.

Abstract: The present invention relates to a catalyst composition for producing polyethylene terephthalate from terephthalic acid and ethylene glycol, comprising: (i) an antimony compound, being present such that the elemental antimony is in a range of about 15 ppm to less than 150 ppm; (ii) a zinc compound, being present such that the elemental zinc is in a range of about 40 to about 160 ppm; as well as a process for the preparation thereof.

Abstract: Polyesters prepared using germanium catalyst in the finishing stage at temperatures less than 285° C. exhibit low loss of Ge catalyst and excellent low acetaldehyde generating characteristics.

Abstract: A random amorphous copolyester is provided. The copolyester of the invention is synthesized by using diacid monomers and diol monomers. The random amorphous copolyester has a structure of the formula (I): wherein R1, R2 is an aromatic or aliphatic monomer, and wherein A, B, C, D, E and F are numbers of repeating units, A is 0-0.8, B is 0-0.8, C is 0-1, D is 0-1, E is 0-0.8, F is 0-0.8, C+D>0.2 and A+B+E+F<0.8. The diacid monomer comprises TPA and an aromatic or aliphatic diacid monomer, the diol monomer comprises EG, 1,3 and 1,4-CHDM, and an aromatic or aliphatic diol monomer.

Abstract: There is now provided a polyester polymer particle having an It.V., a surface, and a center, wherein the It.V. at the surface of the particle is less than 0.25 dL/g higher than the It.V. at the center of the particle. The polyester polymer particle is desirably crystalline to prevent the particles from sticking to each other while drying, and desirably contains less than 10 ppm acetaldehyde. A polyester container, preferably a preform or beverage bottle, is made by feeding crystallized polyester particles having an It.V. of at least 0.70 dL/g to an extrusion zone, melting the particles in the extrusion zone to form a molten polyester polymer composition, and forming a sheet or a molded part from extruded molten polyester polymer, wherein at least a portion of the polyester particles have an It.V. at their surface which does not vary from their It.V. at their center by more than 0.25 dL/g, and the particles have not been solid state polymerized. Such polyester compositions have an It.V.

Abstract: The present invention is a method for efficiently incorporating a nitrogen containing methine light absorber into a polyester resin. The method includes forming a reaction mixture comprising combining a diol component, a diacid component selected from the group consisting of dicarboxylic acids, dicarboxylic acid derivatives, and mixtures thereof, an antimony containing compound, a phosphorus containing compound, a metal containing compound, and a nitrogen containing methine light absorber. The reaction mixture is polymerized in a polycondensation reaction system. In another embodiment the light absorber is added while the reaction products of one reactor are being transferred to the next reactor in the polycondensation reaction system. The present invention is also directed articles made from the polyester resin.

Abstract: Embodiments of the present invention are directed to a polymerization catalyst used to produce polyester. The catalyst comprises at least one metal-containing component, excluding antimony or germanium, and an organic compound component, containing at least one moiety of Ar—O— or Ar—N<, where Ar represents an aryl group.

Abstract: A problem of the invention is to provide a process for producing a polyester with high molecular weight and high quality and having practicality as a container material, etc., which is able to achieve the production for a relatively short period of time of solid phase polycondensation without using a complicated melt polycondensation reaction device and consequently at a low cost and with good efficiency. The invention is concerned with a continuous production process for continuously producing a polyester including an esterification step, a melt polycondensation step, a granulation step and a solid phase polycondensation step, wherein at least two kinds of a catalyst 1 and a catalyst 2 which are satisfied with the following requirements (1) to (3) are successively added as catalysts in two arbitrary different places prior to the granulation step; an intrinsic viscosity of the polyester prepolymer granule obtained in the granulation step is 0.18 dL/g or more and not more than 0.

Abstract: An amorphous polyester chip having superior processing ability is characterized by a moisture content of not more than 300 ppm and a fine particle content of not more than 500 ppm. A preferred embodiment is a copolymerized polyester chip comprising a main repeating unit consisting of ethylene terephthalate, and 1,4-dimethylene-cyclohexane terephthalate or neopentyl terephthalate, wherein the glycol component of the copolymerized polyester has a specific composition of 50 to 85 mol % of ethylene glycol, 12 to 45 mol % of 1,4-cyclohexanedimethanol or neopentyl glycol and 1.5 to 7.0 mol % of diethylene glycol. Such amorphous polyester chip can be obtained by cooling an amorphous polyester obtained by melt polymerization, cutting the polyester to give a chip, feeding the chip in a treatment tank, drying the chip and removing fine particles.

Abstract: A melt phase process for making a polyester polymer melt phase product by adding an antimony containing catalyst to the melt phase, polycondensing the melt containing said catalyst in the melt phase until the It.V. of the melt reaches at least 0.75 dL/g. Polyester polymer melt phase pellets containing antimony residues and having an It.V. of at least 0.75 dL/g are obtained without solid state polymerization. The polyester polymer pellets containing antimony residues and having an It.V. of at least 0.70 dL/g obtained without increasing the molecular weight of the melt phase product by solid state polymerization are fed to an extruder, melted to produce a molten polyester polymer, and extruded through a die to form shaped articles. The melt phase products and articles made thereby have low b* color and/or high L* brightness, and the reaction time to make the melt phase products is short.

Abstract: A melt phase process for making a polyester polymer melt phase product by adding an antimony containing catalyst to the melt phase, polycondensing the melt containing said catalyst in the melt phase until the It.V. of the melt reaches at least 0.75 dL/g. Polyester polymer melt phase pellets containing antimony residues and having an It.V. of at least 0.75 dL/g are obtained without solid state polymerization. The polyester polymer pellets containing antimony residues and having an It.V. of at least 0.70 dL/g obtained without increasing the molecular weight of the melt phase product by solid state polymerization are fed to an extruder, melted to produce a molten polyester polymer, and extruded through a die to form shaped articles. The melt phase products and articles made thereby have low b* color and/or high L* brightness, and the reaction time to make the melt phase products is short.

Abstract: The present invention relates to a biodegradable copolyester of high molecular weight and narrow molecular weight distribution. The copolyester has a Mw of 100,000-600,000 g/mol, and a molecular weight distribution of 1.2-3.

Abstract: A method for manufacturing a crystallizable plastic material is disclosed. The process includes the step of melting an amorphous plastic material, pelletizing the material, crystallizing it and then post condensing the plastic material with the proviso that the plastic material is not subjected to heating after the melting step but prior to the crystallization step and then subjecting the plastic material to sieving after the crystallization step.

Abstract: The present invention is a method for efficiently incorporating a nitrogen containing methine light absorber into a polyester resin. The method includes forming a reaction mixture comprising combining a diol component, a diacid component selected from the group consisting of dicarboxylic acids, dicarboxylic acid derivatives, and mixtures thereof, an antimony containing compound, a phosphorus containing compound, a metal containing compound, and a nitrogen containing methine light absorber. The reaction mixture is polymerized in a polycondensation reaction system. In another embodiment the light absorber is added while the reaction products of one reactor are being transferred to the next reactor in the polycondensation reaction system. The present invention is also directed articles made from the polyester resin.

Abstract: A method is described for the manufacture of polyesters of aromatic dicarboxylic acids with aliphatic and/or cycloaliphatic dials, in which an aromatic dicarboxylic acid in the presence of a monocarboxylic acid or a mixture of a monocarboxylic acid present in a saturated solution with water or another suitable solvent is converted with an aliphatic or cycloaliphatic dial to a dicarboxylic acid alkanediolestercarboxylate and/or its oligomers, which are polycondensed in further process steps to the polyester.

Abstract: This invention provides a novel polycondensation catalyst using no antimony compound, polyester produced by using the same, and a process for producing polyester. A novel catalyst comprising an aluminum compound and a phosphorus compound is used as the polycondensation catalyst in producing polyester. The polyester of this invention can be applied to fibers for clothes, fibers for industrial materials, various films, sheets and molded articles such as bottles and engineering plastics, as well as coatings and adhesives.

Abstract: A novel polymerization catalyst for polyesters, which does not contain any germanium or antimony compound as the main component; polyesters produced with the catalyst; and a process for producing polyesters. This polymerization catalyst is excellent in catalytic activity, little causes thermal degradation of polyesters in melt molding even when neither deactivated nor removed, and can give thermally stable polyesters which little generate foreign matter and are excellent in transparency and color. The polymerization catalyst is one which contains as the first metal-containing component at least one member selected from the group consisting of aluminum and aluminum compounds and which gives polyethylene terephthalate (PET) having a thermal stability parameter (TS) satisfying the relationship: (1) TS<0.3.

Abstract: In a polyester production method, a titanium compound having a radical selected from a carbonyl group, a carboxyl group, or an ester group, and a phosphorous compound having a structure illustrated in Formula (I), are added This yields a polyester composition which does not exhibit increased filter pressure when forming, which has excellent filament and film forming properties, and which has a polymer color tone superb to that of conventional products.

Abstract: A method for preparing a biodegradable copolyester includes: (a) optionally preparing an aromatic prepolymer by reacting a first aromatic dicarboxylic compound with a first aliphatic glycol; (b) reacting the aromatic prepolymer with a second aromatic dicarboxylic compound and a second aliphatic glycol so as to form a first reaction product; (c) reacting the first reaction product with an aliphatic dicarboxylic compound so as to form a second reaction product; and (d) performing polycondensation of the second reaction product.

Abstract: A melt polymerization process for the preparation of poly(1,3-propylene-co-isosorbide) terephthalate (3GIT), new 3GITs and products made from the 3GITs. The process comprises (a) providing a mixture comprising terephthalic acid or its alkyl ester, 1,3-propanediol and isosorbide in a molar ratio of diols to terephthalic acid or its alkyl ester of from about 1.1:1 to about 1.6:1 and a molar ratio of 1,3-propanediol to isosorbide of from about 2:1 to about 10:1; (b) reacting the mixture in an inert atmosphere at a temperature of about 180 to about 245° C., with concurrent removal of a distillate comprising at least 80% of the water or alkanol volatile reaction product, wherein the distillate contains less than about 5 weight % 1,3-propanediol and less than 1 weight % isosorbide; and (c) continuing the reaction in the presence of a polycondensation catalyst at a pressure of about 0.25 to about 2 mm Hg and about 245 to about 260° C.

Abstract: The present invention provides a catalyst for polyester production capable of producing a polyester with high catalytic activity, a process for producing a polyester using the catalyst and a polyester produced thereby. The catalyst comprises a solid titanium compound obtained by dehydro-drying a hydrolyzate obtained by hydrolysis of a titanium halide and which has a molar ratio (OH/Ti) of a hydroxyl group (OH) to titanium (Ti) exceeding 0.09 and less than 4. In the process, the polyester is obtained by polycondensing an aromatic dicarboxylic acid, or an ester-forming derivative thereof, and an aliphatic diol, or ester-forming derivative thereof, in the presence of the catalyst. The resulting polyester has excellent transparency and tint, a titanium content of 1 to 100 ppm, a magnesium content of 1 to 200 ppm and a magnesium to titanium weight ratio of not less than 0.01.