Abstract: A continuous process for producing polyethylene terephthalate polyester from terephthalic acid and ethylene glycol uses a stabilizer, preferably containing phosphorous, to produce a high quality polyethylene terephthalate polyester which is relatively free of the acetaldehyde and discoloration which are associated with the post-polymerization activity of a polymerization catalyst. The stabilizer is preferably added at or after the end of the polymerization reaction prior to polymer processing to deactivate the polymerization catalyst and can increase the throughput of the polyester without adversely affecting the thermal stability of the polyethylene terephthalate polyester. Alternatively, the late addition of the stabilizer can increase the thermal stability of the polyester without adversely affecting the throughput of the polyethylene terephthalate polyester.

Abstract: A soluble mono-alkyl Stannoic Acid/glycol liquid phase catalyst produced from the reaction of a mono-alkyl Stannoic Acid and a glycol at a temperature of from at least 180.degree. C., and its use in preparing high molecular weight polyester polymers.

Abstract: The present invention provides a novel poly(1,3-propylene terephthalate), which is prepared from reacting terephthalic acid and 1,3-propanediol in the presence of an effective catalytic amount of ethylene glycol titanate to undergo esterification to form a monomer; and polymerizing the monomer in the presence of an effective catalytic amount of antimony acetate to obtain poly(1,3-propylene terephthalate). The obtained poly(1,3-propylene terephthalate) (PPT) has an intrinsic viscosity (IV) of 0.65-0.91 dl/g, acid number (--COOH amount) of less than 40 meq/kg, and L*>60. Without adding a pigment, the yellowness b* of PPT is below 9, even below 5. The yellowness b* of PPT even reaches below 3 when a pigment is incorporated.

Abstract: The invention comprises a method for synthesizing polyethylene terephthalate from waste polyethylene terephthalate by cleavage with ethylene glycol and separation of bis(hydroxyethylene) terephthalate from the cleavage mixture with a specific temperature program, recrystallization from water, and esterification and polycondensation with the addition of terephthalic acid.The invention further comprises a method for synthesis of polyethylene naphthalate from waste polyethylene naphthalate in a similar manner.

Abstract: A polyester comprises a dicarboxylic acid moiety comprising terephthalic acid or its ester forming derivative and a diol moiety comprising ethylene glycol and 1,4-cyclohexanedimethanol of 10 to 60 mol % based on the whole diol moiety, the intrinsic viscosity of the polyester being 0.68 to 0.95 dl/g, the "b" value of color tone of the produced pellets of polyester being -5 to 5, the number of the carboxylic acid terminals being not more than 30 eq/ton, and the sum of the numbers of the vinyl terminals, the vinylidene terminals and the methylcyclohexene terminals being not more than 25 eq/ton.

Abstract: An atmospheric pressure process for the continuous production of polyester is disclosed wherein a melt of bis(3-hydroxy propyl) terephthalate, or its low molecular oligomers, obtained by esterifying terephthalic acid or transesterifying dimethyl terephthalate with propylene glycol, is intimately contacted with an inert gas to facilitate polymerization and removal of the reaction by-products. The propylene glycol evolved and the inert gas are recycled.

Abstract: This invention is directed to an improved process for producing a polyester oligomer. The process employs a pipeline reactor, having at least two stages, in which the degree of polymerization of an oligomeric feed material is raised from about 2-10 to about 2-40 and the ratio of carboxyl to hydroxyl end groups in the product is reduced. In a first stage of the process, a monomeric diol or polyol, such as ethylene glycol, is added to a melt of the oligomeric feed material. In a second stage of the process, the molecular weight of the oligomer is increased by removal of volatile reaction by-products, including water and polyol. The oligomer produced by the present invention may be used in making higher molecular weight polyesters.

Abstract: In the production of polyethylene naphthalate of the present invention, the esterification reaction between naphthalenedicarboxylic acid and ethylene glycol is conducted while causing water to be present in a reaction system from a start of reaction, in the presence of at least one catalyst selected from the group consisting of nitric, carboxylic, phosphoric and hydrogenphosphoric acid metal salts and alkyl amines according to necessity, to thereby attain an esterification ratio of 45 to 80%, so that a liquid mixture of naphthalenedicarboxylic acid esterification reaction products containing naphthalenedicarboxylic acid, carboxyl-hydroxyethoxycarbonylnaphthalene and bis(hydroxyethoxycarbonyl)naphthalene is obtained. Subsequently, a crystallized reaction product is separated from this liquid mixture to thereby obtain a mixture of esterification reaction products. Thereafter, this mixture having ethylene glycol added thereto according to necessity is subjected to polycondensation.

Abstract: The present invention provides a method of synthesizing polypropylene terephthalate with no more than 5 ppm acrolein and no more than 3 ppm allyl alcohol. The method comprises direct esterification of terephthalic acid with 1,3-propanediol in the presence of 30 to 200 ppm titanium in the form of an inorganic esterification catalyst containing at least 50 mol % TiO.sub.2 precipitate, blocking the esterification catalyst after esterification by adding 10 to 100 ppm phosphorus in the form of a phosphorus-oxygen compound, and then performing precondensation and polycondensation in the presence of 100 to 300 ppm antimony in the form of a conventional antimony polycondensation catalyst and optional conventional coloring agent.

Abstract: This invention relates to a thermally stable polyester, comprising:a polyester resin prepared by adding a dicarboxylic acid to a glycol compound, said dicarboxylic acid selected from the group consisting of aliphatic dicarboxylic acids having a total of from 3 to 16 carbon atoms, alicyclic dicarboxylic acids having 7 to 12 carbon atoms, aromatic dicarboxylic acids containing a total of from 8 to 16 carbon atoms, and combinations thereof, and wherein said glycol is selected from the group consisting of glycols having from 2 to 12 carbon atoms, glycol ethers having from 4 to 12 carbon atoms, and combinations thereof,said polyester resin having been prepared in the presence of a catalyst system consisting essentially of one or more antimony compounds which is not reacted with .alpha.-hydroxy carboxylic acids, .alpha.,.beta.-dicarboxylic acids or derivatives thereof.

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: This invention relates to a thermally stable polyester, comprising:a polyester resin prepared by adding a dicarboxylic acid to a glycol compound, said dicarboxylic acid selected from the group consisting of aliphatic dicarboxylic acids having a total of from 3 to 16 carbon atoms, alicyclic dicarboxylic acids having 7 to 12 carbon atoms, aromatic dicarboxylic acids containing a total of from 8 to 16 carbon atoms, and combinations thereof, and wherein said glycol is selected from the group consisting of glycols having from 2 to 12 carbon atoms, glycol ethers having from 4 to 12 carbon atoms, and combinations thereof,said polyester resin having been prepared in the presence of a catalyst system consisting essentially of one or more antimony compounds which is not reacted with .alpha.-hydroxy carboxylic acids, .alpha.,.beta.-dicarboxylic acids or derivatives thereof.

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: A method for preparing polyester by use of a catalyst. The method comprises the steps of: esterifying either a terephthalic acid, a dicarboxylic acid containing terephthalic acid or derivatives thereof with either ethylene glycol or a glycol containing ethylene glycol, or derivatives thereof to produce an esterification product containing either bis(.beta.-hydroxyethyl) terephthalate, its low molecular weight polymer, or a combination of .beta.-hydroxyethyl terephthalate and its low molecular weight polymer; and continuously polycondensing the obtained esterification product to prepare a polyester, wherein in the said polycondensing step, a composite polymerization catalyst dissolved in an ethylene glycol or an ethylene glycol-containing solution, consisting of a compound of antimony, a compound of titanium, and a compound of tin is used.

Abstract: A process for producing a polyester film is disclosed, which comprises melt-mixing from 3 to 12 parts by weight of a master polymer comprising a poly(alkylene terephthalate) which contains from 0.3 to 3 wt % inorganic lubricant and has an intrinsic viscosity of 0.5 or higher with from 97 to 88 parts by weight of a poly(alkylene terephthalate) containing no inorganic lubricant and having an intrinsic viscosity of 0.5 or higher, and forming the resulting mixture into a film by the electrostatic casting method. The master polymer is obtained by a process comprising adding to a poly(alkylene terephthalate) oligomer having an average degree of polymerization of 10 or lower an alkylene glycol slurry of an inorganic lubricant and specific amounts of a potassium compound and a phosphorus compound, depolymerizing the oligomer, subsequently adding specific amounts of antimony trioxide and germanium dioxide, and then effecting polycondensation.

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: This invention relates to a three step process for preparing copolyesters exhibiting a neutral hue, high clarity and increased brightness. The process involves reacting terephthalic acid, ethylene glycol, and 1,4-cyclohexanedimethanol in a feed mole ratio of total glycols to dicarboxylic acid of 1.7:1 to 6.0:1, at a temperature of 240.degree. C. to 280.degree. C., and a pressure of 15 psig to 80 psig to form an esterification product; adding a polycondensation catalyst and a toner; and polycondensing the product at a temperature of 260.degree. C. to 290.degree. C. and a reduced pressure to form a high molecular weight copolyester.

Abstract: New polyesteramides having glass transition temperatures (Tg's) of up to 130.degree. C. and heat deflection temperatures that are in the 100.degree. C. to 110.degree. C. range are disclosed. The new polyesteramides of this invention are made by sequential addition of selected diamines to the diacid/glycol melt. The polyesteramides comprise:--?--A--G--!.sub.x --?--A--NH--R--NH--!.sub.y --wherein A is an organic dicarboxylic acid; G is a glycol selected from linear aliphatic diols and cycloaliphatic diols having 5 to 20 carbon atoms; R is selected from alkyl, cycloalkyl, arylkyl, or aryl; and x and y are whole numbers having an x/y ratio between about 9 to about 0.5 and sum of X and Y is from about 2 to about 500.

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: This invention relates to a method of preparing a reinforced polyester composition comprising the steps of:I. mixing(a) at least one cyclic ester oligomer selected from the group consisting of ethylene terephthalate and cyclohexylenedimethylene terephthalate,(b) an organic initiator comprising one to five hydroxy groups which are capable of opening the cyclic ester rings,(c) a catalyst, and(d) a reinforcing material,II. heating the mixture of I at a temperature ranging from 270.degree. C. to 320.degree. C.

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 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: 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 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: An atmospheric pressure process for the continuous production of polyester is disclosed wherein a melt of bis(3-hydroxy propyl) terephthalate, or its low molecular oligomers, obtained by esterifying terephthalic acid or transesterifying dimethyl terephthalate with propylene glycol, is intimately contacted with an inert gas to facilitate polymerization and removal of the reaction byproducts. The propylene glycol evolved and the inert gas are recycled.

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 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: Process for adjusting the haze value of ethylene terephthalate homopolymers and low-modified copolymers to a value in the range of 0.5 to 20 NTU while they are being produced by direct esterification and polycondensation, where an amount of antimony and germanium catalyst that is determined on the basis of the desired degree of turbidity is added before or at the start of the esterification step in the absence of other catalysts and other compounds that would affect the haze value, and after achieving a conversion of 90 to 98%, another dose of antimony catalyst corresponding to a total added amount of Sb+Ge in the range of 160 to 350 ppm is added, and then after addition of the catalyst is concluded, a phosphorus stabilizer is added to the reaction mixture in an amount to correspond to 0 to 50 ppm phosphorus.

Abstract: An atmospheric pressure process for the continuous production of polyester is disclosed wherein a melt of dihydroxy ethyl terephthalate, or its low molecular oligomers, obtained by esterifying terephthalic acid or transesterifying dimethyl terephthalate with ethylene glycol, is intimately contacted with an inert gas to facilitate polymerization and removal of the reaction by-products. The ethylene glycol evolved and the inert gas are recycled.

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: 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: 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 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: The present invention provides a high molecular weight aliphatic polyester which is biodegradable by microorganisms in soils and which is utilized as a molded article as well as a method to prepare the same. This polyester has a structure shown below: ##STR1## as well as those analogous thereto.

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.

Abstract: A linear, highly polymerized polyester is prepared by polycondensing a glycol ester of aromatic dicarboxylic acid and/or a low molecular weight condensate thereof by using as polycondensation catalyst a preformed antimony compound which is obtained from the reaction of esterified trimellitate with an antimony compound selected from a member of antimony halide, antimony carbyxylate and antimony carbyxylate. The above-mentioned esterified trimellitate is prepared by reacting trimellitic acid or trimellitic anhydride with alcohols such as alkyl alcohol or alkane diol and treating successively organic or inorganic base with the resultant reaction product, and comprises, depending on the type of alcohol used, a mixture of 1-alkoxycarbonyl-2,4-benzenedicarboxylate and 2-alkoxycarbonyl-1,4-benzenedicarboxylate or a mixture of 1-(hydroxyalkoxycarbonyl)-2,4-benzenedicarboxylate and as a main 2-(hydroxyalkoxycarbonyl)-1,4-benzenedicarboxylate component.

Abstract: An atmospheric pressure process for the continuous production of polyester is disclosed wherein a melt of dihydroxy ethyl terphthalate, or its low molecular oligomers, obtained by esterifying terephthalic acid or transesterifying dimethyl terephthalate with ethylene glycol, is intimately contacted with an inert gas to facilitate polymerization and removal of the reaction by-products. The ethylene glycol evolved and the inert gas are recycled.

Abstract: Refillable polyethylene terephthalate (PET) bottles are made by injection stretch blow moulding and comprise a threaded neck of transparent amorphous substantially non-oriented PET; a substantially cylindrical body of transparent biaxially oriented amorphous PET from 0.4 to 0.9 mm thick and an area expansion ratio of at least 7; and a base of transparent amorphous substantially non-oriented or partly oriented PET in which the PET is a polyethylene terephthalate polymer randomly modified by replacing from 1 to 6 mole % of the terephthalate units with units of a chain orientation disrupting aromatic dicarboxylic acid, such as iso-phthalic acid, having an Intrinsic Viscosity of at least 0.75. The polymer particularly includes fine metal particles especially of antimony to reduce the reheat, and optionally includes a level of diethylene glycol residues greater than normally present in PET to improve the blowing performance of the polymer.

Abstract: Disclosed is a process for producing polyethylene terephthalate fibers with reduced flammability which comprises the following steps:(a) condensating terephthalic acid and ethylene glycol in a mole ratio of from 1:1.1-1.5 at a temperature of from 180.degree.to 240.degree. C. in the presence of a catalyst;(b) adding a polyalkylene glycol phosphate ester;(c) polycondensating at a temperature of from 265.degree.-280.degree. C. under a pressure decreasing from 760 torr to less than 2 torr to form the polyethylene terepthalate; and(d) melt spinning fibers.

Abstract: Disclosed is a process for the preparation of polyester having an ethylene-terephthalate recurring-unit in the amount of not less than 60 molar % of the total recurring-unit of the polyester by polymerizing a bifunctional carboxylic acid comprising terephthalic acid and glycol comprising ethylene glycol in the presence of an antimony compound, at least one metal compound selected from the group consisting of a glycol-soluble magnesium compound, a glycol-soluble manganese compound and a glycol-soluble zinc compound, a hindered phenol compound, and a sulphur-containing ester compound, wherein the metal compound, the hindered phenol compound and a sulphur-containing ester compound are employed under the following conditions:0.015.ltoreq.A.ltoreq.0.15 (I)0.01.ltoreq.B.ltoreq.0.2 (II)0.01.ltoreq.C.ltoreq.0.2 (III)0.5.ltoreq.B/C.ltoreq.2.

Abstract: According to the present invention there is provided a polyester composition comprising an aromatic polyester having copolymerized therein a compound containing at least one sulfonic acid group or sulfonic acid metal salt group, and crosslinked polymer particles, preferably crosslinked polymer particles coated with a water-soluble polymer. The particles are incorporated in a slurried state into the polymer. There is also provided a laminate film containing the polymer with the particles thus incorporated therein.The polyester composition is superior in uniform dispersibility of the particles, re-agglomeratin does not occur in melt-storage for a long time, and films formed using the polyester composition are superior in traveling performance and abrasion resistance.

Abstract: Macrocyclic poly(alkylene dicarboxylate) oligomers are prepared by the reaction of a dicarboxylic acid chloride such as terephthaloyl chloride with at least one bis(hydroxyalkyl) ester such as bis(4-hydroxybutyl) terephthalate, in the presence of a Lewis acid as catalyst. Illustrative Lewis acids are ferric chloride, zinc chloride, zinc bromide, stannous bromide and antimony pentachloride.

Abstract: A hollow article or sheet of a copolyester which comprises, as main components, terephthalic acid as a dicarboxylic acid component and ethylene glycol as a diol component and which is characterized by:(1) isophthalic acid as a dicarboxylic acid component being from 0.5 to 3.0 mol %,(2) diethylene glycol as a diol component being from 1.0 to 2.5 mol %,(3) the intrinsic viscosity being from 0.60 to 1.50 dl/g,(4) the concentration of terminal carboxyl groups being at most 18 eq/ton, and(5) the content of a cyclic trimer being at most 0.40% by weight.

Abstract: The present invention relates to a process for copolymerizing a dicarboxylic acid, a dialkyl ester, and a diol in the presence of a transesterification catalyst. The process involves heating a mixture containing carboxylic acids and esters in excess diol at elevated temperatures in the presence of a transesterification catalyst and returning any vaporized diol to the reaction vessel until the theoretical amount of alcohol and/or water have been evolved. The alcohol and/or water of reaction is not allowed to return to the vessel. When the theoretical weight of alcohol and/or water is collected, the excess diol is removed and the polymerization is allowed to proceed.

Abstract: The present invention relates to a process for preparing a polyethylene naphthalate possessed with high viscosity, characterized by sloving of various problems of the prior art by controlling the rate of the polycondensation reaction.Particularly, the present invention provides a process for preparing polyethylene naphthalate from an esterification reaction product of naphtalene dicarboxylic acid or an alkyl ester thereof and a diol, which comprises polycondensing the esterification reaction product in the presence of a polycondensation catalyst in two steps wherein the first step is carried out at a pressure ranging from 500 to 30 torr and the second step is carried out at a pressure ranging from 10 to 0.1 torr with controlling the reaction rate such that the differential increase of the intrinsic viscosity of the resultant polymer can satisfy the following equations:IV(t.sub.1)-IV(t.sub.0)<0.4 dl/g (1)IV(t.sub.2)-IV(t.sub.0)>0.3 dl/g (2)wherein: IV(t.sub.

Abstract: Provided are water-dissipatable, sulfo-containing polyesters and polyester-amides having copolymerized therein thermally stable near infrared flourophoric compounds. The polymers are useful in coating or ink compositions, which are in turn useful for marking articles for identification/authentication purposes. Also provided is a method for invisibly marking such articles and a method for detecting and sorting articles by utilizing the near infrared flourophoric ink or coating compositions.

Abstract: Hydrosoluble/hydrodispersible polyester copolycondensates, well suited for the sizing of textile threads, comprise terephthalate, isophthalate, sulfoaryl dicarboxylate, ethylene glycol and polyoxyethylene glycol recurring structural units, have a glass transition temperature ranging from 15.degree. to 40.degree. C. at 85% relative humidity and the turbidity of aqueous formulations thereof are storage-stable over time; such polyester copolycondensates are conveniently prepared by (i) transesterifying admixture of dimethyl terephthalate, dimethyl sulfoaryl dicarboxylate and ethylene glycol, (ii) introducing isophthalic acid and an additional amount of ethylene glycol into the medium of transesterification and therein directly esterifying same, and (iii) polycondensing the resulting product of transesterification/direct esterification.

Abstract: Process for treating poly(esteramides) to improve the heat and storage stability thereof. Polymer is optionally suspended in a liquid medium, treated with an amide group-containing solvent, and then separated from the solvent and liquid medium (if any). Also, poly(esteramides) treated in this process and devices and articles comprising such poly(esteramides).

Abstract: A process for forming polyesters that comprises the steps of esterifying a terephthalic acid and an ethylene glycol to produce an esterification product containing a bis (betahydroxyethyl) terephthalate, and continuously polycondensing the obtained esterification product to form a polyester. In both the esterifying step and the polycondensing step, a reaction catalyst consisting of a compound of antimony and a compound of titanium is used. The weight ratio of the compound of antimony to the compound of titanium is 0.01 to 100. The process of the present invention can considerably reduce both the esterification time and the polycondensation time and provides good color, reduced diethylene glycol content and reduced condensation of terminal carboxyl groups in the resulting polyesters.