Abstract: A polyester for a toner, obtainable by polycondensing an alcohol component and a carboxylic acid component containing a (meth)acrylic acid-modified rosin; and a toner containing the polyester for a toner. The polyester for a toner of the present invention is usable as a resin binder for a toner usable in, for example, developing electrostatic latent images formed in electrophotography, electrostatic recording method, electrostatic printing method or the like.

Abstract: A promoter for a polycondensation reaction used together with a catalyst in a polycondensation reaction, the promoter for a polycondensation reaction comprising a pyrogallol compound having a benzene ring of which three hydrogen atoms adjacent to each other are substituted by hydroxyl groups; and a polycondensation resin obtained by polycondensing raw material monomers using the promoter as defined above and the catalyst. A polycondensation resin can be produced using the promoter of the present invention together with a catalyst in a polycondensation reaction, and the polycondensation resin can be used in various applications including, for example, films, sheets, fibers, toner materials for electrophotography, and the like.

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: 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: 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: Thiourethane prepolymer compositions, thiourethane polymer compositions, methods of making the compositions, and methods of using the thiourethane polymer compositions are provided. The thiourethane polymer composition can be produced by contacting a thiol ester composition and an isocyanate composition to produce a prepolymer composition and then curing the prepolymer composition to produce the thiourethane polymer composition. The prepolymer composition can also include a property modifying agent. In some embodiments, the thiol ester compositions include thiol esters, hydroxy thiol esters, and cross-linked thiol esters.

Abstract: An aliphatic polyester polyether copolymer is provided having an aliphatic polyester moiety comprising 35 to 50 molar % of an aliphatic diol unit, 35 to 50 molar % of an aliphatic dicarboxylic acid unit and 0 to 30 molar % of an aliphatic oxycarboxylic acid unit and a polyether moiety, wherein ?sp/C is not less than 1.40 and the ratio by weight of the polyether moiety to the aliphatic polyester polyether copolymer is 0.1 to 90% by weight.

Abstract: Macrocyclic oligoesters and compositions comprising macrocyclic oligoesters are prepared from intermediate molecular weight polyesters. In one embodiment, a diol is contacted with a dicarboxylic acid or a dicarboxylate in the presence of a catalyst to produce a composition comprising a hydroxyalkyl-terminated polyester oligomer. The hydroxyalkyl-terminated polyester oligomer is heated to produce a composition comprising an intermediate molecular weight polyester which preferably has a molecular weight between about 20,000 Daltons and about 70,000 Daltons. The intermediate molecular weight polyester is heated and a solvent is added prior to or during the heating process to produce a composition comprising a macrocyclic oligoester. An optional step is to separate the macrocyclic oligoester from the composition comprising the macrocyclic oligoester.

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: The present invention provides a production method of biodegradable plastic in which polylactic acid is directly synthesized from lactic acid without employing the conventional route of polylactic acid synthesis from lactic acid via lactide, and apparatus for use in production thereof. In this way, time required for the synthesis of polylactic acid is strikingly shortened and the production cost is reduced. In the production method of biodegradable plastic, polylactic acid, the main component of biodegradable plastic, is obtained by means of condensation polymerization by dehydration of the raw material, lactic acid, under high temperature and reduced pressure in the presence of a metal catalyst.

Abstract: The invention relates to a method for producing high-molecular weight polyesters, such as e.g. polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polynaphthalene terephthalate (PEN), polytrimethylene terephthalate (PTT) and/or polyesters of other dicarboxylic acids and diols including copolymers thereof. The invention relates likewise to a device for implementing this method. The latter concerns a single-stage tower reactor with which a method, comprising only two reactors, is made available for the total process.

Abstract: A method of synthesizing biodegradable aliphatic polyesters from one or more aliphatic dicarboxylic acids or diesters of the said acids and one or more linear or branched aliphatic glycols, comprising a first esterification or transesterification step and a second deglycolation under vacuum step, in which the catalyst is monobutylstannoic acid both for the esterification or transesterification step and for the deglycolation under vacuum step.

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: 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: Cyclic oligomers containing ester linkages are polymerized in the presence of a catalyst having at least one oxygen atom bonded to two metal atoms. At least one of the metal atoms is a tin atom, which is preferably tetravalent, i.e., bonded to three other groups in addition to the oxygen atom. The other metal atom may also be another tin atom, which is again preferably tetravalent, or a zinc, aluminum or titanium atom. The catalyst may contain multiple oxygen atoms that are bonded to two such metal atoms as described. These catalysts are active, efficient polymerization catalysts. They are often liquids at polymerization temperatures. The catalysts can be formed in situ in the polymerization process, which provides additional flexibility in the process and increased storage stability of starting materials.

Abstract: In the invention, a polyester resin having dicarboxylic acid constitutional units and diol constitutional units wherein 5 to 60 mol % of the diol constitutional units has a cyclic acetal skeleton is produced by a process including an oligomerization step and a polymerization step. In the oligomerization step, an ester having a limited acid value is transesterified with a diol having a cyclic acetal skeleton in the presence of a titanium compound to obtain an oligomer. The oligomer is then polymerized in the subsequent polymerization step to increase the molecular weight.

Abstract: A shaped article comprising poly[(trimethylene-co-dianhydrosugar ester) dicarboxylate] or poly(trimethylene-co-dianhydro-dicarboxylate having improved stability in the form of less change of Tg and reduced shrinkage upon storage at elevated temperature is disclosed.

Abstract: A polyester resin produced by polycondensing a dicarboxylic acid component containing an aromatic dicarboxylic acid or its ester-forming derivative as the main component and a diol component containing ethylene glycol as the main component in the presence of at least an antimony compound and a phosphorus compound, via an esterification reaction or an ester exchange reaction, which is characterized in that the amount of antimony eluted when immersed in hot water of 95° C. for 60 minutes in the form of particles having a number average particle weight of 24 mg, is not more than 1 ?g per 1 g of the polyester resin, as antimony atoms (Sb).

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 toner binder for developing electrostatic charge images, which binder comprises a polycondensate polyester resin, said polyester resin being a product formed in the presence of at least one titanium-containing catalyst (A) selected from the group consisting of a titanium halides (A1), a titanium diketone enolate (A2), a titanium carboxylate (A3), a titanyl carboxylate (A4), and a titanyl carboxylate salt (A5). Furthermore, the present invention provides a toner binder for developing electrostatic charge images, which binder comprises a polycondensate polyester resin, said polyester resin being a product formed in the presence of at least one tin-containing catalyst (B) selected from the group consisting of dioctyltin oxide (B1), monobutyltin oxide (B2), and dibutyltin oxide (B3), with the content of tributyltin compounds in (B3) being not more than 250 ppm.

Abstract: There is provided a laminated film for optical use comprising a polyester film which has a lubricity layer containing globular particles in at least one side thereof, wherein the laminated film has a thickness irregularity of 0.5 to 7.0%, and wherein the polyester film contains inert particles derived from catalysts and the amount of the inert particles determined by a dark-field microscopy satisfies the following conditions: the number of inert particles having a particle size of from 1 to 10 ?m is 200 to 20,000/mm2; and the number of inert particles having a particle size of greater than 10 ?m is 10/mm2 or less. The laminated film for optical use which is improved in uniformity, transparency, lubricity, color tone and scratch resistance, which deposits only a reduced amount of low molecular materials, and which is excellent in the adhesion to a layer adopted for various optical purposes.

Abstract: Macrocyclic oligoesters and compositions comprising macrocyclic oligoesters are prepared from intermediate molecular weight polyesters. In one embodiment, a diol is contacted with a dicarboxylic acid or a dicarboxylate in the presence of a catalyst to produce a composition comprising a hydroxyalkyl-terminated polyester oligomer. The hydroxyalkyl-terminated polyester oligomer is heated to produce a composition comprising an intermediate molecular weight polyester which preferably has a molecular weight between about 20,000 Daltons and about 70,000 Daltons. The intermediate molecular weight polyester is heated and a solvent is added prior to or during the heating process to produce a composition comprising a macrocyclic oligoester. An optional step is to separate the macrocyclic oligoester from the composition comprising the macrocyclic oligoester.

Abstract: Biaxially-drawn polyester film for fabrication which is characterized in that it is a film comprising polyester in which ethylene terephthalate units and/or ethylene naphthalate units are the chief structural component, and the melting point of said film is 180-270° C., the angle of contact to water is 70°-120°, and the planar orientation coefficient is 0.08-0.15. This film shows outstanding release properties following repeated use, use after fabrication and use in an aqueous environment and, furthermore, it exhibits stable properties with little variation and, in particular, following lamination to metal sheet such as steel or aluminium, when used as the inner face of a fabricated metal can, it is outstanding in its non-stick properties to the contents, and provides a combination of heat resistance and processability.

Abstract: The present invention relates to specific glyceryl alkoxylated citrate esters and their use in lipsticks. These polymers not only do not have a mal taste, but also have a very pleasant taste. This coupled with their use to prevent syneresis in lipsticks, make these products very desirable in lipstick applications.

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: Macrocyclic oligoesters and compositions comprising macrocyclic oligoesters are prepared from intermediate molecular weight polyesters. In one embodiment, a diol is contacted with a dicarboxylic acid or a dicarboxylate in the presence of a catalyst to produce a composition comprising a hydroxyalkyl-terminated polyester oligomer. The hydroxyalkyl-terminated polyester oligomer is heated to produce a composition comprising an intermediate molecular weight polyester which preferably has a molecular weight between about 20,000 Daltons and about 70,000 Daltons. The intermediate molecular weight polyester is heated and a solvent is added prior to or during the heating process to produce a composition comprising a macrocyclic oligoester. An optional step is to separate the macrocyclic oligoester from the composition comprising the macrocyclic oligoester.

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: The present invention relates to a method for decreasing the cyclic oligomer content level in the manufacturing process of polyethylene terephthalate (PET) and in the PET products produced from said process by adding calcium phosphate at least one selected from the group consisting of a Ca3(PO4)2 structure and a Ca5OH(PO4)3 structure, and a carboxy phosphonic acid having a structure (1) as follows: wherein R1, R2, and R3 are alkyls or hydrogen atoms and R is an alkyl. The method of the prevent invention restrains the production of cyclic oligomers in the polyester chips produced and also decreases the cyclic oligomers regenerated in the rear-end melting process stage of the invention.

Abstract: A polymer comprising poly(alkylene-co-dianhydrosugar ester) dicarboxylate and its preparation by reacting an alkylene diol, terephthalic acid, and a moiety of formula 1 X-Ia-(A-I)n-Ab-X  Formula 1 wherein: A is the ester residue from an anhydrosugar alcohol or dianhydrosugar alcohol, I is the ester residue from a diacid or its dialkyl esters, X is H when linked to an A residue, OH when linked to an I residue derived from a dibasic acid, and OR when linked to an I residue derived from a dialkyl ester of the dibasic acid, R is a C1-C4 straight or branched chain alkyl group, a and b are independently 0 or 1, and n is 1 to 10 is disclosed.

Abstract: A polyester film for dry film resists, which satisfies requirements for transparency, particularly transmittance of radiation having a wavelength around 365 nm, slipperiness, winding properties, resolution and recyclability. A polyester film for dry film resists which has a thickness of 10 to 25 &mgr;m, a haze value of 3% or less and a residual polycondensation metal catalyst content of less than 150 ppm, and a metal antimony content of 15 mmol % or less based on the total of all the acid components, and a laminated polyester film comprising a lubricating layer on at least one side of the above film.

Abstract: The present invention provides processes for producing certain very low inherent viscosity polyesters. Also provided are the low inherent viscosity polyesters in discrete particulate form, and processes for producing the particulate polyesters. The discrete particulate materials are desirable for use in further processes.

Abstract: A polyester resin produced by polycondensing a dicarboxylic acid component containing an aromatic dicarboxylic acid or its ester-forming derivative as the main component and a diol component containing ethylene glycol as the main component in the presence of at least an antimony compound and a phosphorus compound, via an esterification reaction or an ester exchange reaction, which is characterized in that the amount of antimony eluted when immersed in hot water of 95° C. for 60 minutes in the form of particles having a number average particle weight of 24 mg, is not more than 1 &mgr;g per 1 g of the polyester resin, as antimony atoms (Sb).

Abstract: A polyester resin is prepared by polycondensing a dicarboxylic acid component containing terephthalic acid or its ester-forming derivative as the main component, and a diol component containing ethylene glycol as the main component in the presence of (1) a compound of at least one member selected from the group consisting of titanium group elements in Group 4A of the Periodic Table, via an esterification reaction or an ester exchange reaction, wherein the content of copolymerized components other than the terephthalic acid component and the ethylene glycol component, is not more than 4 mole % based on the total dicarboxylic acid component, and in a molded product with a thickness of 3.5 mm injection-molded at 280° C., the difference between the absorbance at a wavelength of 395 nm and the absorbance at a wavelength of 800 nm is at least 0.08, and the difference between the absorbance at a wavelength of 500 nm and the absorbance at a wavelength of 800 nm is at most 0.05.

Abstract: The present invention relates to low viscosity aromatic polyester polyols having an average functionality of two and methods for preparing such polyols. In particular, the invention relates to low viscosity aromatic polyester polyols prepared by reacting a phthalic acid based material with diethylene glycol, a higher functional polyol having an average functionality of greater than two and a long chain alkyl acid, ester or oil. The resulting aromatic polyester polyol has an average functionality of two and has a lower dynamic viscosity as compared to the esterification product of a phthalic acid based material with diethylene glycol alone.

Abstract: This invention is related to a process for preparing polyester polymers using a composite catalyst comprises the steps of 1) esterifying naphthalene dicarboxylic acid or a dicarboxylic acids containing NDCA or ester derivatives thereof, with ethylene glycol or glycols containing ethylene glycol or derivatives thereof to produce esterified compounds or its low molecular weight polymers; and then 2) continuously polycondensing the obtained esterification product to produce polyester polymers; and wherein the process includes using a composite polymerization catalyst which was prepared by reacting titanium compounds and cobalt compounds in the solution containing at least one alcohol. The process yields high quality polyester polymers having a good color and excellent physical properties. The process can considerably reduce both the esterification time and the polycondensation time.

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: An improved process for the polymerization of polytrimethylene terephthalate by esterification of terephthalic acid or dimethylterephthalate with 1,3-propanediol (PDO), precondensation of the esterification product to produce a precondensation product, and polycondensation of the precondensation product to produce polytrimethylene terephthalate wherein excess PDO is removed from the esterification and/or polycondensation stages and PDO vapor is separated from the high boiling fraction (solid byproduct). The improvement comprises: (a) heating the solid byproduct in the presence of about 5 ppm to about 5000 ppm, based on metal, of a metal catalyst selected from the group consisting of one or more 3rd, 4th, or 5th row metal compounds from Groups 3-12 and Groups 14-15 of the Periodic Table (IUPAC 1989) at a temperature of from about 100° C. to about 240° C.

Abstract: A method of synthesizing biodegradable aliphatic polyesters from one or more aliphatic dicarboxylic acids or diesters of the said acids and one or more linear or branched aliphatic glycols, comprising a first esterification or transesterification step and a second deglycolation under vacuum step, in which the catalyst is monobutylstannoic acid both for the esterification or transesterification step and for the deglycolation under vacuum step.

Abstract: Biaxially-drawn polyester film for fabrication which is characterized in that it is a film comprising polyester in which ethylene terephthalate units and/or ethylene naphthalate units are the chief structural component and containing 0.1-2 wt % of a carnauba wax and 1 to 200 ppm of germanium, and the melting point of said film is 180-270° C., the angle of contact to water is 70°-120°, and the planar orientation coefficient is 0.08-0.15. This film shows outstanding release properties following repeated use, use after fabrication and use in an aqueous environment and, furthermore, it exhibits stable properties with little variation and, in particular, following lamination to metal sheet such as steel or aluminium, when used as the inner face of a fabricated metal can, it is outstanding in its non-stick properties to the contents, and provides a combination of heat resistance and processability.

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: Disclosed is a flame retardant polybutyleneterephthalate resin prepared be copolymerizing a phosphorus-based flame retardant represented by the following formula I and a butyleneterephthalate unit: wherein R1 and R2 are different or the same and are methyl or butyl including a hydroxyl group.

Abstract: Methyltin compounds useful as catalysts in high-temperature esterification and polyesterification reactions are described. The esters and polyesters produced by the process possess superior physical/chemical properties such as improved color and thermal stability with less production of undesirable by-products. The greater stability of these catalysts allows their use in multistage polyesterification reactions and leads to lower use levels in some cases.

Abstract: A process for producing a wholly aromatic polyester which is excellent in heat resistance, mechanical properties and yet color and has a high degree of polymerization by melt polymerizing a dicarboxylic acid and a diol directly on an industrial scale at a low cost in a short period of time without esterifying the dicarboxylic acid or diol in advance. To produce the wholly aromatic polyester by reacting and molding an aromatic dicarboxylic acid such as terephthalic acid, an aromatic diol such as 2,2-bis(4-hydroxyphenyl)propane and a diaryl carbonate by heating, a combination of a specific pyridine compound and an alkali metal (bi)carbonate, a combination of a specific pyridine compound and an organic tin compound or a specific titanium compound is existent as a catalyst. Thereby, the wholly aromatic polyester having the above properties is obtained.

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 method of synthesizing biodegradable aliphatic polyesters from one or more aliphatic dicarboxylic acids or diesters of the said acids and one or more linear or branched aliphatic glycols, comprising a first esterification or transesterification step and a second deglycolation under vacuum step, in which the catalyst is monobutylstannoic acid both for the esterification or transesterification step and for the deglycolation under vacuum step.

Abstract: Disclosed is a method for preparing polyester resins copolymerized with glycol for modification such as 1,4-cyclohexanedimethanol, in which the content of said glycol ingredient for modification ranges from 20 to 80 mol % of the total glycol content. Dicarboxylic acid such as terephthalic acid is esterified with ethylene glycol and said glycol for modification. The esterification product is subjected to polycondensation in the presence of a titanium dioxide/silicon dioxide coprecipitate catalyst, said catalyst being in the form of 4% or less strength by weight suspension in glycol. The copolyester prepared as above shows excellent transparency and color properties in addition to being produced at high efficiency.

Abstract: The invention relates to a process for the preparation of polyesters of a glycol and a dicarboxylic acid which comprises the following steps: a) introducing a feedstock comprising one or more glycols and one or more dicarboxylic acids or monoalcohol esters thereof into a reactor vessel, b) heating the feedstock to an elevated temperature to cause the glycols and the acids or monoalcohol esters thereof to polycondense into a polyester, c) removing all of the polyester from the reactor vessel, wherein step b) is carried out in the absence of a preformed polyester (“zero heel” process). A condensation catalyst is added in step a) or b) or both.

Abstract: Macrocyclic oligoesters and compositions comprising macrocyclic oligoesters are prepared from intermediate molecular weight polyesters. In one embodiment, a diol is contacted with a dicarboxylic acid or a dicarboxylate in the presence of a catalyst to produce a composition comprising a hydroxyalkyl-tenninated polyester oligomer. The hydroxyalkyl-terminated polyester oligomer is heated to produce a composition comprising an intermediate molecular weight polyester which preferably has a molecular weight between about 20,000 Daltons and about 70,000 Daltons. The intermediate molecular weight polyester is heated and a solvent is added prior to or during the heating process to produce a composition comprising a macrocyclic oligoester. An optional step is to separate the macrocyclic oligoester from the composition comprising the macrocyclic oligoester.

Abstract: Disclosed is a method for preparing saturated polyester used in various molded products, such as films, synthetic fibers, vessels and housings. In particular, the method improves mechanical properties, including tensile strength or impact resistance, of saturated polyester. In DMT method or TPA method, the saturated polyester is synthesized through transesterification or esterification and polycondensation, in which metal compounds, such as metal acetate compounds, metal hydroxides, and metal oxides, are added in the larger amounts upon synthesis, and thus crystalline internal grains are formed, thereby improving the mechanical properties. As such, the metal compound can be used alone or in combination with a phosphorous-based compound.

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.