Abstract: A low-cost way to modulate the reactivity and acid number of polyetherester thermoset resins is disclosed. "Beginning" and "end" methods for making dicyclopentadiene (DCPD)-modified polyetherester resins are described. The "beginning" method comprises first heating a polyether, DCPD, a diol, an insertion catalyst, and a carboxylic acid derivative to produce a mixture that contains the polyether and a DCPD-diol diester adduct. Increasing the temperature causes insertion of the DCPD-diol diester into the polyether to give a DCPD polyetherester resin. The "end" method reacts a polyetherester resin made by insertion with DCPD to give a DCPD polyetherester resin. Compared with DCPD polyester resins, those of the invention give more flexible thermosets. Compared with unmodified polyetherester resins, the DCPD polyetherester resins offer formulators more control over curing, which eliminates mold distortion and shrinking or cracking of thermoset parts.

Abstract: Processes for making storage-stable epoxy-capped polyetherester resins are disclosed. In one process, a polyetherester resin is first made by inserting a carboxylic acid derivative into a polyether. Reacting the resin with a capping agent gives an intermediate resin with a reduced content of free carboxylic acid groups. Finally, the intermediate resin reacts with an epoxy compound in the presence of a finishing catalyst under conditions effective to give an epoxy-capped resin. The resins have low weight average molecular weights (less than about 8000), narrow molecular weight distributions (less than 6), and low viscosities, making them an excellent choice for low-VOC formulations. The finishing catalyst helps to minimize resin viscosity drift and improves shelf stability. Curing the resins with a vinyl monomer gives thermosets with an excellent balance of physical properties, including excellent water resistance.

Abstract: Formed products such as foams, fabrics for industrial materials, filaments, nonwoven fabrics, composite materials and films which are degradable after use with ease in the natural environment are prepared by using a high molecular weight aliphatic polyester obtained by direct polycondensation of an aliphatic polyhydric alcohol with aliphatic polybasic acid or additionally hydroxycarboxylic acid or oligomers of these materials in a reaction mixture containing a solvent.

Abstract: Unsaturated, thermosetting, brominated phthalic anhydride/polyol polyester resins are prepared by reacting brominated phthalic anhydride with polyol and an unsaturated polycarboxylic acid compound in the presence of an acid neutralizing agent under reaction conditions so as to form an unsaturated polyester resin product, the proportions of reactants being selected so as to provide, (i) at least about a 5:4 mole ratio of total moles of polyol to the sum of the moles of brominated phthalic anhydride, unsaturated polycarboxylic acid compound and any saturated polycarboxylic acid compounds in the reaction, and (ii) a bromine content of at least about 40 weight percent in the unsaturated polyester resin product.

Abstract: A biaxially extended polyester film comprising light calcium carbonate particles, spherical silica particles and .gamma.- or .delta.-alumina particles or a mixture thereof treated with a silane coupling agent prepared by the inventive process possesses excellent surface and physical properties.

Abstract: An increase in the molecular weight of polyester and recycled polyester can be achieved by blending said polyester with a difunctional epoxy resin and a sterically hindered hydroxyphenylalkylphosphonic acid ester or half-ester and heating the blend to above the melting point (glass transition temperature) of the polyester.

Abstract: A resin composition comprising a saturated polyester resin consisting chiefly of a hydroxyalkanoate unit, a heat-moldable hydroxyl group-containing resin having a vinyl alcohol unit, and an alkaline earth metal carbonate, a molded article composed of this resin composition and, particularly, a container and a multi-layer plastic container having an outer layer formed of this resin composition and an inner layer of a resin consisting chiefly of an ethylene-vinyl alcohol copolymer. The resin composition and the molded articles thereof exhibit not only excellent mechanical properties but also excellent bio-disintegrating property.

Abstract: A process to prepare a high molecular weight aliphatic polyester is disclosed, where a catalyst is portionwise added, and a radical scavenger is also added. The aliphatic polyester obtained has a number average molecular weight larger than 70,000.

Abstract: Oxysulfonylated polyesters, well suited for conversion into oriented composite polyester films, are prepared by polycondensing a lower alkyl diester of at least one aliphatic dicarboxylic acid and a lower alkyl diester of at least one aromatic dicarboxylic acid bearing an oxysulfonyl substituent, and optionally a lower alkyl diester of at least one aromatic dicarboxylic acid, with at least one diol, in the presence of a catalytically effective amount of at least one titanium compound and at least one manganese carboxylate.

Abstract: A zeolite polycondensation catalyst comprising an alkali- or alkaline earth metal aluminum silicate zeolite having an original water content of 12 to 30 weight % and a solubility, measured at 260.degree. C., in an esterification mixture consisting essentially of bis(hydroxy ethylene)terephthalate, of over 8.0 weight %, and an average particle size of less than 1.0.mu.. The present invention is also a process for the production of polyester using this catalyst.

Abstract: The present invention provides novel hydrogel-forming, self-solvating, absorbable polyester copolymers capable of selective, segmental association into compliant hydrogels upon contacting an aqueous environment.

Abstract: A loose tube for an optical fiber comprising a polybutylene terephthalate. The polybutylene terephthalate has a terminal carboxyl group concentration of 10 eq./10.sup.6 g.multidot.polymer or less and an intrinsic viscosity ?.eta.!, measured at 25.degree. C. in orthochlorophenol, of 0.9 to 1.4 dl/g.

Abstract: A process for making high-performance polyetherester resins and thermosets is disclosed. A polyether polyol reacts with a dicarboxylic acid or anhydride in the presence of an insertion catalyst to produce an acid-terminated polyetherester resin. Reaction of this resin reacts with a primary diol or a diepoxy compound gives a chain-extended polyetherester resin that can be cured with a vinyl monomer to produce a high-performance polyetherester thermoset. Properties of the thermosets rival or exceed those of more expensive high-performance iso and vinyl ester resins.

Abstract: An improved clarity copolyester of a diethylene glycol modified poly(ethylene terephthalate) has a b* value of less than 15, preferably less than 10. The copolyester composition has an inherent viscosity of about 0.4 to 1.0 dL/g and comprises (A) 100 mol percent dicarboxylic acid residue component, (B) 100 mol percent diol residue component, (C) catalyst residues and (D) color control agent residues. The dicarboxylic acid residue component comprises at least 75 mol percent of terephthalic acid residues. The diol residue component comprises 10 to 50 mol percent diethylene glycol residue and 50 to 90 mol percent ethylene glycol residue. The catalyst residues comprise 20 to 100 ppm manganese, 50 to 300 ppm antimony, 0 to 100 ppm titanium and 40 to 150 ppm phosphorus, based on the weight of the copolyester.

Abstract: An improved process for making polyetherester resins is disclosed. The process comprises reacting a polyether with a diol diester in the presence of a catalyst that promotes random insertion of the diester into carbon-oxygen bonds of the polyether to produce the polyetherester resin. The process of the invention offers many advantages, including higher resin yields, reduced by-product generation, and the ability to make resins with low color and low acid numbers. The resins are useful for making polyetherester thermosets.

Abstract: There are disclosed a wholly aromatic polyester represented by formula I with enhanced flame retardance and chemical stability, and a method for the preparing the same. The polymer is prepared in interface polymerization wherein an alkali aqueous phase containing cyclotriphosphagene-containing bisphenols is in contact with an organic phase containing aromatic dicarboxylic acid chlorides in the presence of a phase transfer catalyst. ##STR1## wherein m and n each are an integer which satisfies the following conditions: 0<m/(m+n)<1 and 0<n/(m+n)<1; X represents --O--, --S--, --SO.sub.2 --, --SO--, --CO--, an alkylene group of C.sub.1-4, or an alkylidene group of C.sub.1-4 ; and R.sub.1, R.sub.2, R.sub.3, R.sub.1 ', R.sub.2 ', R.sub.3 ' and R.sub.4 ' are the same or different, and represent a hydrogen atom, a halogen atom, or an alkyl group of C.sub.1-4 or the derivatives thereof, respectively.

Abstract: This invention relates to a polyester resin prepared by adding one or more dicarboxylic acid components to one or more glycol components containing 1,4-cyclohexanedimethanol equalling 100 mole %, the polyester resin having been prepared in the presence of a catalyst/stabilizer system consisting essentially of antimony compounds and phosphorous compounds and compounds selected from the group consisting essentially of zinc compounds, gallium compounds, and silicon compounds.

Abstract: The present invention provides inks which contain a near infrared fluorophoric compound incorporated into a water-dissipatible polyester backbone. The inks of the present invention are preferably colorless or "invisible" but could be made slightly colored if desirable. Specifically, the inks of the present invention comprise:A. between about 1 and 10 weight percent of at least one water-dissipatable polyester having from about 0.1 ppm by weight to about 10% by weight of a thermally stable near infrared fluorophoric compound copolymerized therein;B. between about 5 and 75 weight percent of at least aliphatic humectant;C. between about 0 and 15 weight percent of at least one lower aliphatic alcohol of no more than 3 carbon atoms;D. water and optionally up to about 2 weight percent of one or more additives;wherein the weight percentages of components A-D equal 100%.

Abstract: Provided are an aliphatic polyester carbonate having biodegradability and having a content of carbonate unit of at least 5 mol %, a weight-average molecular weight of at least 100,000, a melt viscosity of 2,000-50,000 poises at 190.degree. C. and under a load of 60 kg and a melting point of 70.degree.-180.degree. C., and a process for producing said aliphatic polyester carbonate which comprises reacting an aliphatic dihydroxy compound with an aliphatic dibasic acid in the presence of an ester exchange catalyst to obtain an oligomer and then reacting the oligomer with a diaryl carbonate in the presence of the ester exchange catalyst. A phosphorus compound may be added to the aliphatic polyester carbonate for the purpose of stabilization.

Abstract: A cobalt/aluminum catalyst is used in the polymerization reaction to form polyesters of terephthalic acid and an ethylene glycol.

Abstract: This invention relates to a polyester resin prepared by adding one or more dicarboxylic acid components to one or more glycol components containing 1,4-cyclohexanedimethanol equalling 100 mole %,the polyester resin having been prepared in the presence of a catalyst/stabilizer system consisting essentially of antimony compounds and phosphorous compounds and compounds selected from the group consisting essentially of zinc compounds, gallium compounds, and silicon compounds.

Abstract: A process for preparing a degradable copolymer of aliphatic polyester comprising the steps of reacting two or more kinds of aliphatic polyester homopolymer in the presence of a catalyst in a reaction mixture containing an organic solvent, and a degradable copolymer of aliphatic polyester obtained by said preparation process. The copolymers exhibits high transparency in addition to excellent strength and elongation, can be processed into various molded articles and formed items such as films and filaments, and can provide heat resistance by heat treatment of said molded articles and formed items. The copolymer can be suitably utilized for processed articles such as a film, breathable film, sheet, textile, monofilament, multifilament, yarn, non-woven fabric, flat yarn, staple, crimped fiber, ribbed tape, split yarn, conjugate fiber, laminate, blow-bottle, sheet, stretched sheet, foam and net.

Abstract: A catalyst composition for use in a polycondensation reaction for making poly(ethylene terephthalate) from terephthalic acid comprising: (a) an antimony salt catalyst present in a range from about 10 to about 1,000 ppm; (b) a metal salt catalyst of at least one of cobalt, magnesium, zinc, manganese, calcium, and lead, present in a range from about 10 to about 500 ppm; and (c) an alkali metal acetate, present in a range from about 10 to about 500 ppm; all amounts are based on the metallic elements relative to the theoretical yield of the poly(ethylene terephthalate), by weight, to be made from the terephthalic acid. The catalyst composition was found to have increased the reaction rate in the production of poly(ethylene terephthalate), as well as improved the color of the produced product, by reducing the degree of yellowness in the final poly(ethylene terephthalate) product. Attenuation of the yellowish color indicates a reduction in the amount of undesired side reaction product.

Abstract: A process for producing an anisotropic melt-phase forming polymer involving separate acetylation and polymerization steps, which utilizes controlled vapor phase reflux to reduce reactant loss and assist in maintaining the stoichiometry of the process.

Abstract: A novel process for the preparation of a high molecular lactic copolymer polyester is provided, which includes allowing a lactide (A), a polyester terminated by hydroxyl group at both ends (B1), a polyvalent carboxylic acid having 3 or more functionalities and/or acid anhydride thereof (C) to undergo ring opening copolymerization in the presence of a ring opening polymerization catalyst (D). A novel process is also provided which includes allowing the lactide (A) and the polyester (B1) to undergo ring opening copolymerization in the presence of the catalyst (D) to prepare a polyester, and then reacting the polyester with the component (C).

Abstract: The present invention provides inks which contain a near infrared fluorophoric compound incorporated into a water-dissipatible polyester backbone. The inks of the present invention are preferably colorless or "invisible" but could be made slightly colored if desirable. Specifically, the inks of the present invention comprise:A. between about 1 and 10 weight percent of at least one water-dissipatable polyester having from about 0.1 ppm by weight to about 10% by weight of a thermally stable near infrared fluorophoric compound copolymerized therein;B. between about 5 and 75 weight percent of at least aliphatic humectant;C. between about 0 and 15 weight percent of at least one lower aliphatic alcohol of no more than 3 carbon atoms;D. water and optionally up to about 2 weight percent of one or more additives;wherein the weight percentages of components A-D equal 100%.

Abstract: A two-step process for making polyetherester resins is disclosed. A low molecular weight polyol reacts with an aromatic dicarboxylic acid in step one to produce a polyester intermediate. In step two, the polyester intermediate reacts with an anhydride or an aliphatic dicarboxylic acid in the presence of an insertion catalyst to produce a polyetherester resin that contains greater than about 10 wt. % of recurring units derived from the aromatic dicarboxylic acid. The polyetheresters are useful for making thermoset resins with excellent mechanical properties and chemical resistance.

Abstract: The present invention provides novel hydrogel-forming, self-solvating, absorbable polyester copolymers capable of selective, segmental association into compliant hydrogels upon contacting an aqueous environment. Methods of using the novel polyester copolymers of the invention in humans are also disclosed for providing a protective barrier to prevent post-surgical adhesion, treatment of defects in conduits such as blood vessels, and controlled release of a biologically active agent for modulating cellular events such as wound healing and tissue regeneration or therapeutic treatment of diseases such as infection of the periodontium, dry socket, bone, skin, vaginal, and nail infections.

Abstract: Thermoplastic polyesters are prepared by multistage polycondensation of dihydroxy compounds with dicarboxylic acids or esters or ester-forming derivatives thereof by a process in which, in at least one first stage, an alkali metal compound or an alkaline earth metal compound is added in an amount of from 1 to 10 mmol, calculated as alkali metal or alkaline earth metal, per kg of polyester, and at least one further stage is carried out as a solid-phase condensation.

Abstract: A process for making polyetheresters is disclosed. A polyether is reacted with a carboxylic acid in the presence of a strong protic acid or a metal salt of a strong protic acid to promote insertion of the carboxylic acid into polyether carbon-oxygen bonds to produce a polyetherester. The polyetheresters are useful for various applications in the polyurethane and unsaturated polyester industries.

Abstract: Filaments of ethylene terephthalate polyester copolymers that contain a lithium salt of a glycollate of 5-sulfo-isophthalic acid provide improvements over commercially-available basic-dyeable polyester filaments.

Abstract: A catalyst composition for use in a polycondensation reaction for making poly(ethylene terephthalate) from terephthalic acid comprising: (a) an antimony salt catalyst present in a range from about 10 to about 1,000 ppm; (b) a metal salt catalyst of at least one of cobalt, magnesium, zinc, manganese, calcium, and lead, present in a range from about 10 to about 500 ppm; and (c) a phosphorus salt co-catalyst selected from the group consisting of alkali metal phosphates, alkali metal phosphites, alkali metal hypophosphites and alkali metal polyphosphates, present in a range from about 10 to about 500 ppm; all amounts are based on the metallic or phosphorus element relative to the theoretical yield of the poly(ethylene terephthalate), by weight, to be made from the terephthalic acid.

Abstract: This invention relates to a polyester resin prepared by adding one or more dicarboxylic acid components to one or more glycol components containing 1,4-cyclohexanedimethanol equalling 100 mole %,the polyester resin having been prepared in the presence of a catalyst/stabilizer system consisting essentially of antimony compounds and phosphorous compounds and compounds selected from the group consisting essentially of zinc compounds, gallium compounds, and silicon compounds.

Abstract: The invention relates to a polyester resin for producing a thick-walled bottles having high transparency and a neutral color. The polyester resin, containing at least one antimony compound, one germanium compound and one phosphorus compound, is produced by reacting a dicarboxylic acid with polyhydric alcohols and also contains cyclohexane dimentanol. The polyhydric alcohols are a mixture of ethylene glycol and at least 0.5% cyclohexane dimethanol. The result, more particularly, is a low rate of crystallization for obtaining thick-walled hollow members.

Abstract: A process for producing polylactic acid includes the steps of polycondensing lactic acid to a lactic acid prepolymer having a weight-average molecular weight of 10,000-50,000 in a batch-type polymerization reactor, and polycondensing the lactic acid prepolymer to lactic acid polymer having a weight-average molecular weight of at least 100,000 by means of a screw-type extruder.

Abstract: A process for making polyetheresters is disclosed. A polyether is reacted with a carboxylic acid in the presence of a strong protic acid or a metal salt of a strong protic acid to promote insertion of the carboxylic acid into polyether carbon-oxygen bonds to produce a polyetherester. The polyetheresters are useful for various applications in the polyurethane and unsaturated polyester industries.

Abstract: Compositions are described comprising thermoplastic polyester resins comprising polyester molecules ending in terminal groups, wherein all or a part of the terminal groups are represented by the general formula --R--SO.sub.3 L, wherein R is a divalent aliphatic hydrocarbon having 1-20 carbon atoms and L is an alkali metal; an inorganic compound mixture, wherein said inorganic compound mixture comprises one or more compounds selected from the group consisting of: inorganic compounds consisting of M, Mg, Si, O and F and inorganic compounds consisting of M, Mg and F, wherein M is an alkali metal; and wherein the energy of said composition satisfies the following formulas (1) and (2):U.ltoreq.1,300 (cal/mole) (1).sigma..times..sigma.e<2.8.times.10.sup.5 (cal.sup.2 /m.sup.4)(2)wherein U is an activation energy, .sigma. is a lateral surface energy and .sigma.e is a fold surface energy.

Abstract: The present invention provides novel one-step processes for preparing highly branched macromolecule polymers that have highly controlled molecular architectures. The process comprise the reaction of a branching monomer such as a substituted phenyl compound having the formula: ##STR1## wherein R.sub.1, R.sub.2, and R.sub.3 are defined herein, with a second monomer (an end-capping monomer) such as a phenolic ester for a sufficient period of time and at a sufficient temperature to directly produce the highly branched polymer, in a single processing step.

Abstract: A poly(methylene oxalate) polymer, [poly(oxy(1,2-dioxo-1,2-ethanediyl)oxymethylene)], a bis(tetrabutylammonium) oxalate salt, methods of synthesis thereof and methods of use are provided. Poly(methylene oxalate) is nearly insoluble in all common organic solvents, does not melt and is resistant to fire. Applications are as a light-weight material for use at high temperatures, e.g., as a structural material in aircraft and space vehicles, as a binder for brake systems, and as an insulator for microelectronic components.

Abstract: A process is provided for preparing basic-dyeable polyester polymer, and shaped articles therefrom, such as fibers, films and bottles, involving using the metal sulfonate salt of a glycollate of isophthalic acid as a polymerization catalyst in making ethylene terephthalate polyester copolymers. This reduces or even avoids the need to add a conventional polymerization catalyst, such as antimony trioxide, especially when making polyesters delustered with titanium dioxide.

Abstract: A heat resistant phosphorus-containing polymeric flame retardant and a process for preparing the same are disclosed. The process is characterized in that in polycondensation a selected metal salt serving as cocatalyst is used to catalyze a phosphorus-containing compound, a saturated dicarboxylic acid or the derivatives thereof, and a diol to form a high phosphorus content, high molecular weight flame retardant. The selected metal salts can promote the polymerization of phosphorus-containing compounds and polyester, and can inhibit side reactions and depolymerization so as to increase the phosphorus content of the resulting products and reduce the manufacturing cost. The flame retardants thus prepared can endure processing at an elevated temperature and thus are suitable for being applied in flame retardant fibers, fabrics, nonwoven fabrics, adhesives, and plastics.

Abstract: Aromatic polycarbonates manufactured by polycondensation of a dihydric compound and a carbonic acid diester using at least two reactors in series have improved color and low impurities content when filtered before the final reactor and again before the final reactor outlet.

Abstract: The invention provides a method of manufacturing polyesters which comprises an esterifying step wherein a dicarboxylic acid and a dihydroxyl compound are esterified and the next liquid phase polycondensation step wherein the resulting ester is subjected to liquid phase polycondensation in the presence of a polycondensation catalyst while a distillate which contains an reacted dihydroxyl compound and the polycondensation catalyst is distilled, wherein the distillate is subjected to a purification treatment comprising:(a) a distilling step;(b) a filtering step; and(c) a decoloring stepand then the thus purified distillate is recovered and supplied to the esterifying step. A further method comprises a purification treatment comprising:(a) a distilling step;(b) a depolymerizing step; and(c) a decoloring step.

Abstract: A catalyst composition for use in the preparation of poly(butylene terephthalate) from dimethyl terephthalate, comprising: (a) a titanium compound primary catalyst, from about 0.0005 PHR to about 5 PHR; (b) a first co-catalyst containing at least one of Zn, Co, Mn, Mg, Ca, or Pb series compounds, between about 0.0001 PHR and 5 PHR; and (c) a second co-catalyst containing an alkali metal phosphate, an alkali metal phosphite, an alkali hypophosphite, or an alkali metal polyphosphate between about 0.0001 PHR and 5 PHR; wherein PHR represents parts of the primary catalyst or the co-catalyst per one hundred parts, by weight, of dimethyl terephthalate. Preferred titanium compounds include tetrabutyl titanate or tetra(isopropyl)titanate. Preferred metal compounds for use as first co-catalyst are metal acetates. The alkali metal phosphate can be a phosphate salt containing one, two, or three metal groups; and the alkali metal phosphite can be a phosphite salt containing one or two metal groups.

Abstract: Novel compounds having use as contrast agents in magnetic resonance imaging, as well as other uses, are described. The compounds are comprised of a copolymer which comprises at least two of a first monomer of the formula X.sub.1 -(CHR.sub.2 CHR.sub.2 --Y).sub.n --(CHR.sub.2).sub.m --CHR.sub.2 CHR.sub.2 --X.sub.2, wherein X.sub.1 and X.sub.2 are, independently, OH, NH.sub.2, NHR.sub.1, COOH, COOR.sub.1, SH, or Z, Y is O, NH, NR.sub.1, S, or CO, n is 0-10,000, m is 0 or 1, each Z is, independently, Cl, Br, or I, each R.sub.1 is, independently, a C.sub.1 -C.sub.20 substituted alkyl or cycloalkyl, and each R.sub.2 is, independently, H or OH, and at least one of a second monomer which is a polynitrilo chelating agent having at least two COOH, COOR.sub.1, or COZ groups, the first and second monomers being bound to one another to form a copolymer through an ester, amide, or carboxylic thioester linkage of at least one of the OH, NH.sub.2, NHR.sub.1, COOH, COOR.sub.

Abstract: Novel polyesters prepared from a diol, a dicarboxylic acid or ester forming reactive derivative thereof and an aromatic amino acid, ester or alcohol are disclosed.

Abstract: A catalyst composition for use in the preparation of poly(butylene terephthalate) from dimethyl terephthalate, comprising: (a) a titanium compound primary catalyst, from about 0.01 PHR to about 1 PHR; and (b) an alkali metal phosphate or alkali metal phosphite co-catalyst, from about 0.001 PHR to about 1 PHR; wherein PHR represents parts of the primary catalyst or the co-catalyst per one hundred parts, by weight, of dimethyl terephthalate. Preferred titanium compounds include tetrabutyl titanate or tetra(isopropyl) titanate; the alkali metal phosphate can be a phosphate salt containing one, two, or three metal groups; and the alkali metal phosphite can be a phosphite salt containing one or two metal groups. With this catalyst composition, the transesterification rate was increased by 10 percent or more. Furthermore, the reaction product poly(butylene terephthalate) shows an increased intrinsic viscosity over those without the co-catalyst, indicating a greater degree of polymerization.

Abstract: A preparation process of polyhydroxycarboxylic acid having an inherent viscosity of 0.3 dl/g or more by dehydrating polycondensation of lactic acid containing hydroxycarboxylic acid in an organic solvent in the presence or absence of a catalyst, comprising using a hydroxycarboxylic acid raw material which comprises one or more impurities selected from the group consisting of methanol, ethanol, acetic acid, pyruvic acid, fumaric acid, methyl lactate, ethyl lactate and butyl lactate in a total amount of 0.3% by mole or less for the amount of said hydroxycarboxylic acid raw material.

Abstract: A cobalt/aluminum/chlorine catalyst for the polymerization of polyesters of terephthalic acid and an ethylene glycol, a process for the preparation of such catalysts, a process for the polymerization of terephthalic acid and an ethylene glycol, a process of spinning fibers of such polymers where reduced spinneret wiping is achieved, and fibers of such polyesters containing catalyst residues of cobalt/ aluminum/chlorine, and films or bottles of said polymer.

Abstract: A polyester-polycarbonate composition comprising (A) at least one polyester prepared by the reaction of at least one alkanediol with at least one dicarboxylic acid or dialkyl ester thereof in the presence of a metallic catalyst, (B) at least one polycarbonate, (C) at least one organosilicate, the organosilicate being present in an amount effective to inhibit ester-carbonate interchange in the composition, optionally, (D) an organic or inorganic colorant, (E) an impact modifier, and (F) a stabilizer. A method for stabilizing polyester-polycarbonate compositions against ester-carbonate interchange is also provided.