Abstract: The present disclosure provides a polyester including residues of formulas (i), (ii), (iii), and (iv): for example, terephthalic acid, for example, ethylene glycol, for example, cyclohexanedimethanol, and for example, tricyclodecane dimethanol, in which R1 is an aromatic group, R2 is a C2-C6 straight-chain hydrocarbon group, * represents a linking bond. Based on 100 mol % of a sum of the residues of the formula (ii), the formula (iii) and the formula (iv), a content of the residue of the formula (iii) ranges from 50 mol % to 85 mol %, and the residue of the formula (iv) ranges from 12 mol % to 40 mol %.

Abstract: The present invention relates to a composition comprising the reaction product of a block copolymer based on OH-functional polyolefin which is unhydrogenated, preferably polybutadiene, and cyclic esters in the form of a polyol having at least 1.8, preferably at least two, OH groups and at least one isocyanate compound having at least two isocyanate groups, which is notable in that the composition includes at least 0.0001% to 40% by weight of titanium and has a content of free isocyanate groups of at least 0.1% by weight based on the overall composition, to a process for preparation thereof and to the use of the composition for bonding of substrates.

Abstract: The present application provides salen indium catalysts of the following general structure and the corresponding dimers. The salen indium catalysts are particularly useful in catalyzing ring-opening polymerizations of cyclic ester monomers, such as lactides. Also provided herein are methods of using the salen indium complexes to catalyze polymerization of cyclic ester monomers. Of particular interest is the successful polymerization of lactides using the present salen indium catalysts to produce poly(lactic acid) having high isotacticity.

Abstract: The invention provides a metal alkoxide complex of Formula (I), wherein X, M, R1, R2, R3, m, n, y and z are as defined in the Description. The invention also provides a catalyst composition comprising the metal alkoxide complex and a hydroxy-containing compound, wherein the molar ratio of the metal alkoxide complex to the hydroxy-containing compound is 1:01-1000. The invention also provides a production method of poly-?- caprolactone or polyactide, wherein an ?-caprolactone monomer or a lactide monomer is reacted in the presence of the metal alkoxide complex or catalyst composition to obtain poly-?-caprolactone or polylactide. The metal alkoxide complex and the catalyst composition thereof can be used to catalyze the synthesis of poly-?- caprolactone or polylactide with a high efficiency.

Abstract: A catalyst composition comprising a cation and an anion of the formula Anq?Qpm+, wherein m, n, p, and q are positive integers, wherein m*p=n*q, wherein Qm+is an organo onium, and Aq?is an anion, provided that at least one Aq?is selected from the formula (I) wherein each R independently is H, halo, alkyl, aryl, aralkyl, or cycloalkyl, and which also may be halogenated, fluorinated, or perfluorinated, wherein two or more of R and R? groups may together form a ring, wherein each R group independently may contain one or more heteroatom(s), wherein R? can be the same as R, with the proviso that R? cannot be halo, and wherein the catalyst composition is essentially free of hydrocarbon containing alcohol. Also provided are a fluoropolymer composition including this curative, a method of making a fluoropolymer, and fluoropolymer articles containing curable or cured fluoropolymer compositions.

Abstract: A polyester polymer comprising alkylene arylate units, said polymer having an It.V. of at least 0.72 dl/g, a vinyl ends concentration of at least 0.8 microequivalents per gram, an AA generation rate of less than 20 ppm are prepared by addition of a catalyst deactivator either late in the polycondensation or upon remelting of a solid polyester polymer.

Abstract: Methods for producing biocompatible compositions are provided. The biocompatible compositions include an aliphatic polyester macromer produced without the use of solvents or catalysts. The resulting aliphatic polyester macromer may be reacted with a polyisocyanate to form an end-capped aliphatic polyester macromer which, in turn, may be reacted with a polyol to produce a polyurethane. The polyurethane, in turn, may be reacted with a second polyisocyanate to produce an isocyanate-functional polyurethane. The compositions prepared by the methods of the present disclosure may be used as adhesives or sealants for medical/surgical uses.

Abstract: The invention relates to a process for preparing lactic acid polymers of highly crystallinity and molecular weight, the process comprising melt polymerization of a lactide to form prepolymers having active end groups followed by solid state polymerization. The polymerization is carried out in the presence of a catalyst complex comprising a lactide, an organic metal-oxo compound and a lactic acid oligomer. The residual lactide after the melt polymerization is removed by heating the reaction mixture in the temperature range of 98° C. to a temperature less than the melting point of the prepolymer. The metal to oligomer ratio in the catalyst complex is in the range of 0.1 to 10, preferably in the range of 0.5 to 5, more preferably in the range of 0.8 to 1.5.

Abstract: The present invention provides a polyester resin obtained by using an aluminum compound and a phosphorus compound as a polymerization catalyst, containing greater than or equal to 85% by mol of an ethylene terephthalate structural unit, wherein the content of an aluminum-based contaminant with respect to the mass of the polyester resin is less than or equal to 100 ppb, and the content of a phosphorus compound represented by a specific structure is 5 to 11 ppm. The present invention is able to provide a polyester resin capable of keeping high transparency of the molded body when it is sequentially polymerized and produced on a commercial scale, and having such characteristics that crystallization of a mouth plug part can be easily controlled when it is used for a heat resistant bottle, and whitening is less likely to occur at the time of heating in molding when it is used as a sheet for molding.

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: Disclosed is a method for synthesizing star polymers having controlled tacticity. The method comprises reacting a lactone-based monomer having at least one stereocentre and a poly-functional initiator in the presence of at least one catalyst. In particular embodiments, the lactone-based monomer is L-lactide or DL-lactide, the poly-functional initiator is dipentaerythritol, and the at least one catalyst is an aluminum-salen catalyst (tBu[O,N,N,O] AlMe) or an aluminum-salan catalyst (Cl[O,N,N,O] AlMe). Star polymers comprising at least two arms and having heterotacticity bias, isotacticity bias, or stereoblocks of different tacticity bias are produced.

Abstract: The present invention provides a method for producing a polyester resin, comprising carrying out a hot-water treatment and a heat treatment, in this order, of polyester prepolymer particles obtained by melt polycondensation of a dicarboxylic acid component and a diol component. The hot-water treatment comprises bringing the polyester prepolymer particles with an intrinsic viscosity of from at least 0.10 dL/g to at most 1.0 dL/g and with a density of at most 1.36 g/cm3 into contact with hot water at a temperature higher than the glass transition temperature of the polyester prepolymer particles and less than 100° C., under the condition satisfying the following formula (1): 40?(T?Tg)t?6000??(1) wherein t is a hot-water treatment time (second), T is the temperature of the hot water (° C.) and Tg is the glass transition temperature (° C.) of the polyester prepolymer particles.

Abstract: A catalyst composition comprises the reaction product of an alkoxide or condensed alkoxide of a metal M, selected from titanium, zirconium, hafnium, aluminium, or a lanthanide, an alcohol containing at least two hydroxyl groups, a 2-hydroxy carboxylic acid and a base, wherein the molar ratio of base to 2-hydroxy carboxylic acid is in the range 0.01-0.79:1. The composition is useful as a catalyst for esterification reactions, especially for the production of polyesters such as polyethylene terephthalate, polytrimethylene terephthalate and polybutylene terephthalate.

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: Polymer blends suitable for packaging are disclosed that include one or more impact modifiers; and one or more polyethylene terephthalate homopolymers or copolymers obtained by a melt phase polymerization using a catalyst system comprising aluminum atoms in an amount, for example, from about 3 ppm to about 60 ppm and one or more alkaline earth metal atoms, alkali metal atoms, or alkali compound residues in an amount, for example, from about 1 ppm to about 25 ppm, in each case based on the weight of the one or more polyethylene terephthalate homopolymers or copolymers The polymer blends disclosed exhibit improved low temperature toughness compared with blends made using polymers prepared with conventional catalyst systems.

Abstract: Thermosetting compositions comprising an adhesion-promoting agent are disclosed. The adhesion-promoting agent is derived from boric acid or an equivalent and an ester having two or more functional groups that are derived at least in part from a 1,3-polyol.

Abstract: A curative composition suitable for fluoroelastomers comprising an anion of Formula III: wherein each Rf independently is R—CF2 or a perfluoroalkyl group having from 1 to 8 carbon atoms, wherein R is H, halo, alkyl, aryl, or cycloalkyl, having up to 8 carbon atoms and which also may be halogenated, fluorinated, or perfluorinated, and which may contain a heteroatom, wherein X is a linking group, and wherein n is a positive integer. Also provided are a fluoropolymer composition including this curative, a method of making a fluoropolymer, and fluoropolymer articles containing curable or cured fluoropolymer compositions.

Abstract: This invention provides a polyester and a polyester molded product, which, while maintaining color tone, transparency, and thermal stability, can realize a high polycondensation rate, are less likely to cause the production of polycondensation catalyst-derived undesired materials, and can simultaneously meet both quality and cost effectiveness requirements, which can exhibit the characteristic features, for example, in the fields of ultrafine fibers, high transparent films for optical use, or ultrahigh transparent molded products. These advantages can be realized by using, in the production of a polyester in the presence of an aluminum compound-containing polyester polycondensation catalyst, an aluminum compound having an absorbance of not more than 0.0132 as measured in the form of an aqueous aluminum compound solution, prepared by dissolving the aluminum compound in pure water to give a concentration of 2.

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: The invention relates to a process for preparing lactic acid polymers of highly crystallinity and molecular weight, the process comprising melt polymerization of a lactide to form prepolymers having active end groups followed by solid state polymerization. The polymerization is carried out in the presence of a catalyst complex comprising a lactide, an organic metal-oxo compound and a lactic acid oligomer. The residual lactide after the melt polymerization is removed by heating the reaction mixture in the temperature range of 98° C. to a temperature less than the melting point of the prepolymer. The metal to oligomer ratio in the catalyst complex is in the range of 0.1 to 10, preferably in the range of 0.5 to 5, more preferably in the range of 0.8 to 1.

Abstract: A method for producing a PC copolymer with improved productivity is provided. The PC copolymer has a specific structure and the method uses a diester diol-containing monomer as a raw material. The polycarbonate copolymer is produced by reacting a diester diol-containing monomer, a divalent phenol, and a carbonate precursor by interfacial polymerization, wherein the diester diol-containing monomer is a product of reaction between a hydroxybenzoic acid or an esterified product thereof and a polyalkylene glycol, wherein the esterification degree of hydroxyl groups of the polyalkylene glycol is 50 to 90 mol %.

Abstract: A polycarbonate-polyester block copolymer includes a polycarbonate block and a polyester block, each having specific structures. The block copolymer can be prepared, at least in part, from renewable feedstocks. In some forms, the block copolymer includes biodegradable segments that facilitate structural breakdown of objects molded from the block copolymer. Methods of preparing the block copolymer are described as are compositions that include it and articles prepared from it.

Abstract: Polyesters whose polycondensation is catalyzed by titanium-containing catalysts and which are susceptible to acetaldehyde formation during polycondensation or subsequent molding operations are prepared with low finished acetaldehyde content and reduced acetaldehyde generation by adding an ammonium or amine salt of an oxyphosphorus-acid. Polyesters, especially polyethylene terephthalate, may be produced with high inherent viscosity in reduced processing time, without the necessity of further polymerization in the solid state.

Abstract: Metal amide and metal alkoxide species have been found to catalyze the ring opening polymerization of macrocyclic polyester oligomers. The catalysts provide rapid polymerization, high monomer conversion, high molecular weight, and a mechanically sound material.

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: A polycarbonate-polyester block copolymer includes a polycarbonate block and a polyester block, each having specific structures. The block copolymer can be prepared, at least in part, from renewable feedstocks. In some forms, the block copolymer includes biodegradable segments that facilitate structural breakdown of objects molded from the block copolymer. Methods of preparing the block copolymer are described as are- compositions that include it and articles prepared from it.

Abstract: A curative composition comprising a cation and an anion of the formula Anq?Qpm+, wherein m, n, p, and q are positive integers, wherein m*p=n*q, wherein Qm+ is an organo onium, and Aq? is an anion, provided that at least one Aq? is selected from the formula: wherein each R independently is H, halo, alkyl, aryl, aralkyl, or cycloalkyl, and which also may be halogenated, fluorinated, or perfluorinated, wherein two or more of R and R? groups may together form a ring, wherein each R group independently may contain one or more heteroatom(s), wherein R? can be the same as R, with the proviso that R? cannot be halo. Also provided are a fluoropolymer composition including this curative, a method of making a fluoropolymer, and fluoropolymer articles containing curable or cured fluoropolymer compositions.

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: This invention provides a novel polymerization catalyst other than antimony compounds, polyester produced by using the same and a process for producing polyester. The polycondensation catalyst of this invention is a polyester polymerization catalyst comprising an aluminum compound and a phosphorus compound having a specific structure. Further, this invention relates to polyester produced by using this polyester polymerization catalyst and a process for producing polyester. Further, this invention relates to fibers, films and hollow molded articles comprising the polyester.

Abstract: This invention relates to a process for the preparation of a 3-hydroxycarboxylic acid from a 3-hydroxynitrile. More specifically, 3-hydroxyvaleronitrile is converted to 3-hydroxyvaleric acid in high yield at up to 100% conversion, using as an enzyme catalyst 1) nitrile hydratase activity and amidase activity or 2) nitrilase activity of a microbial cell. 3-Hydroxyvaleric acid is used as a substitute for ?-caprolactone in the preparation of highly branched copolyester.

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 method for manufacturing antibacterial polyester master batches and fibers containing nano-silver particles, the method includes the acts of: mixing a reducing agent, glycol and a silver precursor together to compose a first mixture; esterifying terephthalic acid and glycol to compose a second mixture containing block polymers; mixing the first and second mixtures to make the block polymers further polymerize to achieve a polyester liquid containing nano-silver particles; optionally, cooling the polyester liquid to solidify; and selectively, granulating the solidified polyester to obtain a polyester master batches or melting spinning the polyester to obtain polyester fibers. By reducing the silver ions during polymerizing reaction, the reduced silver particles are separated by polymerized polyester molecules so that the silver particles are evenly distributed inside the polyester master batches without coagulation.

Abstract: A composition and a process for producing the composition are disclosed. The composition comprises (1) repeat units derived from a carbonyl compound and a glycol and (2) one or more ultrafine metal oxides. The process can comprise (1) contacting, in the presence of a catalyst and optionally one or more ultrafine metal oxides, a carbonyl compound such as dicarboxylic acid with a glycol under a condition sufficient to produce polyester wherein the glycol can be pretreated with a metal oxide or (2) incorporating an ultrafine metal oxide into or onto polyester. Also disclosed is a process for substantially removing, or reducing the content of, an aldehyde in a glycol which comprises contacting the glycol with at least one metal oxide.

Abstract: Disclosed is a process that comprises contacting, in the presence of an esterification or transesterification or polycondensation catalyst composition, a toner, and a phosphorus compound, a carbonyl compound and an alcohol under a condition suitable for esterification, transesterification, or polymerization.

Abstract: A wholly aromatic polyester carbonate having a good color and excellent heat resistant stability. This polymer had an extremely low alkali metal content of 10 ppm or less. This polymer is advantageously produced by reacting an aromatic dicarboxylic acid, aromatic diol and diaryl carbonate in a specific molar ratio in the presence of a pyridine-based compound as a catalyst.

Abstract: Glycol starting materials for manufacturing a polyester molded body containing 1 to 20% by weight of dispersed superfine ceramic powder aggregates relative to the total weight of the glycol for enabling polyester molded bodies having a high mechanical strength and transparency to be manufactured. The superfine ceramic powder aggregates dispersed in the glycol starting material have a mean particle size of 0.05 to 0.5 ?m as measured with a laser diffraction particle size distribution analyzer, and wherein the peak indicated in a particle size distribution curve of the superfine ceramic powder aggregates obtained based on the results of the measurement satisfies the relationship of w/h?0.7, wherein h is the peak height and w is the peak width at one half of the peak height (a half-width).

Abstract: A composition and a process for producing the composition are disclosed. The composition comprises (1) repeat units derived from a carbonyl compound and a glycol and (2) one or more ultrafine metal oxides. The process can comprise (1) contacting, in the presence of a catalyst and optionally one or more ultrafine metal oxides, a carbonyl compound such as dicarboxylic acid with a glycol under a condition sufficient to produce polyester wherein the glycol can be pretreated with a metal oxide or (2) incorporating an ultrafine metal oxide into or onto polyester. Also disclosed is a process for substantially removing, or reducing the content of, an aldehyde in a glycol which comprises contacting the glycol with at least one metal oxide.

Abstract: The invention relates to polycondensation resins which are prepared by polycondensation of compounds having a low molecular weight and separation of small molecules in the presence of at least one hetergeneous catalyst. The invention also relates to polyaddition resins which are prepared by polyaddition in the presence of at least one heterogeneous catalyst. The invention further relates to the use of said polycondensation resins and polyaddition resins for the preparation of moulded parts, adhesives and coating materials.

Abstract: By the present invention, there are provided a catalyst for polyester preparation, which comprises a solid titanium compound containing titanium, oxygen, carbon and hydrogen and having a Ti—O bond and which has a maximum solubility in ethylene glycol, as measured when the catalyst is dissolved in ethylene glycol under heating at 150° C., of not less than 3,000 ppm in terms of a titanium atom, a catalyst for polyester preparation, which comprises a titanium-containing solution wherein a contact product of a hydrolyzate of a titanium halide or a hydrolyzate of a titanium alkoxide with a polyhydric alcohol is dissolved in ethylene glycol in an amount of 3,000 to 100,000 ppm in terms of a titanium atom, a process for preparing a polyester using the catalyst, and a polyester prepared by the process.

Abstract: The invention relates to fibers, particularly binder fibers, made from polyesters and the polyesters themselves. The polyesters are the product of a reaction between a glycol component and a dicarboxylic acid component where the glycol component contains at least 50 mole % of a four carbon diol, such as 1,4-butanediol, or a six carbon diol, such as 1,6-hexanediol or a mixture of a four carbon and six carbon diol. Typically, the polyesters of the invention are semicrystalline and/or crystalline and have a specific melting point ranging from about 140 to about 185° C. The polyesters of the invention may be formed into a variety of products, especially binder fibers for nonwoven fabrics, textile/industrial yarns and fabrics, composites and other molded articles.

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.

Abstract: A process for producing a polyester. The process comprises polymerizing a polymerization mixture comprising (i) a carbonyl compound or an oligomer of a carbonyl compound and (ii) a glycol, in the presence of a titanium catalyst composition, to produce the polyester, wherein a coated titanium dioxide comprising a titanium dioxide and a coat is added before or during the polymerizing.

Abstract: The production of linear polyester by the interchange of ester radicals or esterification and polycondensation of multivalent alcohols with multivalent carboxylic acids takes place by means of catalysts. In order that the catalyst features the lowest possible content of catalytically active metal compound, the carrier substance that forms the heterogeneous phase comprises particles of the finest grain and of porous structure and features a surface of great inner, reactive and/or coordinated centers, whereby a catalytically active metal compound is adsorbed in the pores.

Abstract: The present invention provides a catalyst for polyester production capable of producing a polyester with high catalytic activity and a process for producing a polyester using the catalyst. The catalyst for polyester production comprises a solid titanium compound which is 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. The present invention also provides a method to obtain a polyester having a small increase of the acetaldehyde content during the molding. This method comprises bringing a polyester, which is obtained by the use of a titanium compound catalyst and in which the reaction has been completed, into contact with a phosphoric ester aqueous solution or the like having a concentration of not less than 10 ppm in terms of phosphorus atom.

Abstract: For the production of polyesters and copolyesters, coprecipitates are used individually or in a mixture as polycondensation catalysts, the coprecipitates being prepared by simultaneous hydrolytic precipitation of a titanium compound and a metallic compound of a metal selected from the groups IA, IIA, VIIIA, IB, IIB, IIIB, and IVB, whereby the titanium compound and the metallic compound are, independently of one another, an alkylate, alcoholate, or carboxylate of titanium or the metal, respectively, and the molar ratio of the titanium compound to the metallic compound is ≧50:50 mol/mol. The coprecipitates exhibit a higher catalytic activity than Sb2O3 which results in a prefered amount of usage of only 10 to 100 ppm with respect to the esters or oligoesters to undergo polycondensation.

Abstract: A process for preparing polytrimethylene terephthalate in which a carbonyl-containing 1,3-propanediol stream is purified for reuse of the 1,3-propanediol. The process involves reacting, under condensation polymerization conditions, terephthalic acid and a molar excess of 1,3-propanediol, with vacuum distillation and condensation of a major portion of the unreacted 1,3-propanediol. To this condensed stream is added a sufficient amount of base to raise the pH to a value greater than 7, and from this base-containing condensate the 1,3-propanediol is distilled and recycled to the polymerization reaction.

Abstract: The present invention relates to a polyester polymerization catalyst, comprising a solution containing an aluminum compound and an alkali compound, with water or an organic solvent or a mixture consisting of water and an organic solvent as the medium, a production method thereof, and a polyester production method, in which the product obtained by the esterification reaction or ester interchange reaction between an aromatic dicarboxylic acid or any of its ester forming derivative and a diol is polycondensed, to produce a polyester, comprising the use of said polymerization catalyst containing an aluminum compound.The present invention can provide a polyester excellent in processability and can overcome such problems as spinneret contamination, filtration pressure rise, filament breaking, film breaking and foreign matter production in the production process of products such as fibers, films, resins and bottles.

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.