Abstract: A method of producing an aromatic polyester by distilling a low-boiling fraction from a polycondensation vessel containing a reaction product obtained by acetylating raw monomers of the aromatic polyester with acetic anhydride, wherein the polycondensation vessel is provided with a partial condenser, and controlling a temperature of the low-boiling fraction distilled from the partial condenser within a range from 80 to 150° C. while the amount of the low-boiling fraction distilled from the partial condenser is within a range from 50% to 90% based on a theoretical recovery amount is provided; and according to this method, adhesion of low-molecular compounds to a partial condenser in the production can be prevented and an improvement in yield of the aromatic polyester and stabilization of product quality can be accomplished.

Abstract: A mixture of a polyester, such as poly(ethylene terephthalate) PET, and a second polymer which is poly(vinyl alcohol) or an ethylene/vinyl alcohol copolymer when extrusion compounded exhibits a lower residual acetaldehyde content than does PET alone when similarly treated. The invention pertains to any polyester used in the manufacture of bottles or containers which in turn are used to store consumer materials, especially food, beverages and most especially water.

Abstract: An amorphous copolyester having a maximum melt viscosity at 1 radian/second and at about 260 to about 290° C. of about 12000 poise, a glass transition temperature ranging from about 88° C. to about 120° C., and an inherent viscosity of at least about 0.6 dl/g. The amorphous copolyesters comprise the reaction product of a diol component and a dicarboxylic acid component. The diol component comprises residues of from about 5.0 to about 50 mole % of 2,2′-(sulfonylbis (4,1-phenyleneoxy))-bis(ethanol) which has the following chemical formula: and from about 50 to about 95 mole % of a mixture of at least two diols selected from the group consisting of ethylene glycol, neopentyl glycol, 1,3-propanediol, 1,4-butanediol, 1,4-cyclohexanedimethanol, and mixture thereof. The dicarboxylic acid component comprises residues of terephthalic acid, isophthalic acid, 1,4-cyclohexandedicarboxylic acid, 2,6-naphthalene dicarboxylic acid and mixtures thereof.

Abstract: A branched polyester resin of the Formula wherein n and m represent randomly repeating segments, and the number of n and m segments in the polymer backbone are each of from about 10 to about 10,000; X is an alkylene group, an olefinic group, or an arylene; Y is an organic dioxy group or radical of I, II, or mixtures thereof; Z is an organic trioxy radical of III, IV, or mixtures thereof; and wherein R and R1 is a hydrogen atom or an alkyl group; G is an alkylene or arylene group, and a is 0 or 1.

Abstract: Provided is a liquid crystalline polyester resin for extrusion molding having a solder heat resistant temperature of 250.degree. C. or more, wherein the ratio ((viscosity 2b)/(viscosity 1b)) of the melt viscosity (viscosity 1b) under a shearing speed of 1000/sec at the flow initiation temperature and the melt viscosity (viscosity 2b) under the same shearing speed at a temperature 20.degree. C. higher than the flow initiation temperature is from 0.10 to 0.70. The extrusion molding material of the above-described liquid crystalline polyester resin has excellent heat resistance, and can provide an extrusion molded article, especially a film having excellent appearance.

Abstract: Process for producing highly stretchable, amorphous anisotropic melt-forming polymers having recurring units derived from p-hydroxybenzoic acid, 6-hydroxy-2-naphthoic acid, at least one aromatic diacid and an aromatic diol and/or hydroxyamine component, at least a portion of which is 4,4'-biphenol, which comprises incorporating into such polymers recurring units derived from resorcinol and at least one additional monomer that provides the resulting polymer with selected meta linkages, wherein each of said recurring units is present in the polymer in specified amounts.

Abstract: A process for the preparation of an unsaturated polyester which comprises (i) reacting an organic diol with a cyclic akylene carbonate in the presence of a first catalyst to thereby form a polyalkoxy diol, and (ii) optionally adding thereto a further amount of cyclic alkylene carbonate in the presence of a second catalyst, and (iii) subsequently polycondensing the resulting mixture with a dicarboxylic acid.

Abstract: A process is disclosed for the preparation of a polyester polymer or polyester copolymer under superatmospheric pressure conditions in a pipe or tubular reaction under turbannular flow conditions. Reaction material having a glycol equivalents to carboxylic acid equivalents mole ratio of from 1.0:1 to 1.2:1, together with a superatmospheric dense gaseous medium are fed co-currently to the reactor. Dicarboxylic acid and/or diol raw materials may be injected into any of the reaction zones in the process during operation to achieve the overall desired mole ratio balance. The process operates at temperatures of from about 220.degree. C. to about 320.degree. C., with turbannular flow achieved before the polymer product and gas exit the reactor process. The pressure in the reaction zones can be in the range from 15 psia to 2500 psia.

Abstract: A potassium catalyst is used in combination with a cobalt catalyst to increase the reaction rate and/or reduce the reaction temperature of a melt polymerization process for producing an anisotropic melt-phase forming polymer derived from p-hydroxybenzoic acid, 6-hydroxy-2-naphthoic acid, aromatic hydroxycarboxylic acid, aromatic diol, at least a portion of which is resorcinol and at least one aromatic dicarboxylic acid, compared to a like process wherein either catalyst is used alone.

Abstract: Polyester compositions containing terephthalate, 2,6-naphthalate and/or isophthalate moieties, and showing improved properties are disclosed.

Abstract: Polytrimethylene terephthalate is prepared in a process which includes adding a hindered phenol and an aromatic organophosphite to the polymerization reaction mixture. The process generates a reduced level of acrolein and prepares an improved polyester product compared with processes without the phenol and organophosphite additives.

Abstract: A liquid-crystalline resin composition comprising 100 parts by weight of a semi-aromatic liquid-crystalline polyester and/or a semi-aromatic liquid-crystalline polyester-amide, from 0.001 to 5 parts by weight of at least one or more compounds selected from phosphorous acid, hypophosphorous acid and their salts, and from 0.01 to 10 parts by weight of red phosphorus has good flame retardancy, low anisotropy, good heat resistance and good hydrolysis resistance, and is useful as engineering plastic.

Abstract: A slow speed wheel with high abrasion resistance, good riding attributes and excellent bounce from a composition comprising at least 20 wt % of a segmented thermoplastic copolyester or a blend of copolyesters consisting of essentially of a multiplicity of recurring long chain ester units and short chain ester units joined head-to-tail through ester linkages, said long chain ester units being represented by the formula (A): ##STR1## and said short chain units being represented by the formula (B): ##STR2## wherein said short chain ester units make up between about 10 to about 95 wt % of said copolyester or blend of copolyesters; G is a divalent radical remaining after the removal of terminal hydroxyl groups from a polyether glycol copolymer based on poly(propylene oxide) and poly(ethylene oxide); R is a divalent radical remaining after removal of carboxyl groups from a aromatic dicarboxylic acid; D is a divalent radical remaining after removal of hydroxyl groups from a diol.

Abstract: A process for the preparation of an unsaturated polyester which comprises (i) reacting an organic diol with a cyclic akylene carbonate in the presence of a first catalyst to thereby form a polyalkoxy diol, and (ii) optionally adding thereto a further amount of cyclic alkylene carbonate in the presence of a second catalyst, and (iii) subsequently polycondensing the resulting mixture with a dicarboxylic acid.

Abstract: A polyester fiber made from a polymer having ethylene glycol moieties, isosorbide moieties and terepthaloyl moieties, and the method of making the fiber is described. The polyester fiber is used to form articles suitable for commercial, especially textile, and industrial uses, and has an inherent viscosity of at least 0.35 dL/g when measured as a 1% (weight/volume) solution of the polyester in o-chlorophenol at a temperature of 25.degree. C.

Abstract: A polyester having increased UV absorption comprising (i) a residue of a dicarboxylic acid component comprising terephthalic and from about 1 to about 20 mole % of isophthalic acid, (ii) a residue of a glycol component comprising ethylene glycol, and (iii) from about 0.01 mole % to about 15 mole % of a residue of an aromatic diol derivative, wherein the aromatic diol derivative has a least two polyester reactive groups that are capable of participating in a polyester-forming reaction and the total mole % for components (i), (ii) and (iii) is 200 mole %.

Abstract: Biodegradable resin products consisting essentially of a polymeric resin of polyethylene, starch, polyesters such as polylactic acid, or other suitable polyesters. In admixture with the resin is a particulate vapor phase corrosion inhibitor selected from amine salts, ammonium benzoate, triazole derivatives, tall oil imidazolines, alkali metal molybdates, alkali dibasic acid salts, and mixtures thereof, and is present in an amount ranging from between about 1% and 3% by weight of the polymeric resin.

Abstract: A thermotropic liquid crystalline polymer constituted of repeat units derived from hydroquinone, terephthalic acid, isophthalic acid, 2,6-naphthalene dicarboxylic acid, and 4-hydroxybenzoic acid, all present in defined amounts. Such polymer has excellent physical properties and high temperature stability. It is suitable as a molding resin.

Abstract: A branched random aliphatic-aromatic copolyesters suitable for foaming has increased melt viscosity and melt strength during extrusion and comprises repeating units of:[--{(O--R.sup.1 --O).sub.a --(CO--R.sup.2 --CO).sub.b }--{(O--R.sup.3 --O).sub.c --(CO--Ar--CO).sub.d }--](BA).sub.x.The mole percent of the acid components and diol components are each based on 100 mole percent. The aliphatic acid residue, --CO--R.sup.2 --CO--, is present in an amount b ranging from 30 to 95 percent and the aromatic acid residue, --CO--Ar--CO--, is present in an amount d ranging from 5 to 70 percent. The diol residues, --O--R.sup.1 --O-- and --O--R.sup.3 --O--, are present in an amount a of 0 to 100 mol percent and in an amount c of 100 to 0 mol percent, respectively. The branching agent, BA, is present in an amount x of 0.01 to 10 weight percent based on the total weight of acid residues, diol residues and branching agent. A foamed article of the branched random aliphatic-aromatic copolyesters is disclosed.

Abstract: A polymer composition having naphthalenedicarboxylic residue includes a fluorescence quenching benzylidene compound capable of absorbing ultraviolet light radiation. In a preferred embodiment, the composition includes at least a 0.1 mole percent of naphthalene-2,6-dicarboxylate and about 0.01 mole percent to about 5 mole percent of a benzylidene compound having the following structure: ##STR1## wherein R is selected from the group consisting of hydrogen, C.sub.1 -C.sub.8 alkyl, substituted C.sub.1 -C.sub.8 alkyl, C.sub.3 -C.sub.8 alkenyl, C.sub.3 -C.sub.8 alkynyl, C.sub.3 -C.sub.8 cycloalkyl, C.sub.3 -C.sub.8 cycloalkenyl and --R.sub.2 --X, wherein R.sub.2 is selected from the group consisting of C.sub.1 -C.sub.8 alkylene, C.sub.2 -C.sub.8 alkylene-O--C.sub.2 -C.sub.8 alkylene, C.sub.2 -C.sub.8 alkylene-S--C.sub.1 -C.sub.8 alkylene, C.sub.2 -C.sub.8 alkylene, C.sub.2 -C.sub.8 alkylene-S--C.sub.2 -C.sub.8 alkylene, C.sub.2 -C.sub.8 alkylene-N(SO.sub.2 C.sub.1-C.sub.8 alkyl)-C.sub.2 -C.sub.

Abstract: There are provided liquid crystalline polyesters comprising 4'-hydroxy-4-stilbenecarboxylic acid type units, dicarboxylic acid units acting as a mesogen such as 4,4'-stilbenecarboxylic acid and catechol units as essential ingredients, and a liquid crystalline polyester composition comprising said polyesters and optically active liquid crystalline polyesters consisting essentially of 4,4'-stilbenedicarboxylic acid type units and aliphatic diol units having asymmetric carbons.

Abstract: Polyesters are described which are substantially the condensation products of at least one dicarboxylic acid, at least one volatile diol and at least one hydroxyl-functional component with functionality greater than 2 which controls ultimate viscosity. The products are suitable vehicles for the formulated thixotropic gels for centrifugal separation of fluids such as serum into high and low density components of, for example, separation of mixtures of cells on the basis of density.

Abstract: A hydroxycarboxylic acid copolyester of R-stereospecific configuration contains a majority of first repeating units capable of forming a highly crystalline high-melting homopolyester and a minority of second repeating units capable when randomly copolycondensed with said first repeating units of lowering the melting point of said homopolyester and is characterised by one or more of: higher crystalline melting point, shorter crystallising time, higher notched impact strength at age 1 month, as compared with corresponding random polyester, and said majority repeating units in the polyester chain being present in blocks longer than correspond to their over-all molar proportionality. The copolyester may be made by fermentation, controlling the distribution of repeating units by reference to the pattern of feeding substrates corresponding to the respective repeating units.

Abstract: Disclosed is a select class of liquid crystalline polyesters and molding compositions comprising the polyesters and glass fiber. The liquid crystalline polyesters consist essentially of (1) diacid residues consisting essentially of (i) cyclohexanedicarboxylic acid residues and (ii) other diacid residues selected from terephthalic acid residues, 2,6-naphthalene-dicarboxylic acid residues, or a mixture thereof; (2) diol residues consisting essentially of hydroquinone residues, 4,4'-biphenol residues or a mixture thereof; and, optionally, (3) p-hydroxybenzoic acid residues. In the above definition, the moles of diol residues are equal to the moles of diacid residues and the total of the (1), (2) and (3) mole percentages is equal to 100. The liquid crystalline polyesters have melting points determined by differential scanning calorimetry equal to or less than 360.degree. C.

Abstract: A process for the preparation of an esterification product comprises reacting a polyfunctional organic acid or anhydride and a cyclic organic carbonate compound in the presence of a catalyst to form an esterification product. The catalyst comprises a quaternary ammonium salt and a component selected from the group consisting of a metal, a salt of a metal, and mixtures thereof.

Abstract: A polyester film made from a polymer having ethylene glycol moieties, isosorbide moieties and terepthaloyl moieties, and the method of making the film is described. The polyester film is used to form articles such as films, lacquers, labels, capacitors, insulators, and the like, and has an inherent viscosity of at least 0.35 dL/g when measured as a 1% (weight/volume) solution of the polyester in o-chlorophenol at a temperature of 25.degree. C.

Abstract: Disclosed are weatherable polyester soft block copolymer compositions comprising copolymers of resorcinol or alternatively phenol, aromatic dicarboxylic acid, and a aliphatic dicarboxylic acid based structural units. These polyester soft block copolymers comprise a substantial proportion of direct linkages between the resorcinol or alternatively the phenol, and the aromatic dicarboxylic acid based structural units, the balance of the linkages being between resorcinol and the aliphatic dicarboxylic acid based structural units.

Abstract: A resin for coating formation which comprises a polyarylate comprising 2,2-bis(3-methyl-4-hydroxyphenyl)propane units and a divalent carboxylic acid component comprising 10 to 90 mol % of terephthalic acid units and 90 to 10 mol % of isophthalic acid units, having an inherent viscosity measured in 1,1,2,2-tetrachloroethane at a concentration of 1 g/dl at 25.degree. C. of 0.85 or more, and having a carboxyl value of 20 mol/ton or less. Also disclosed is a process for producing the resin by interfacial polymerization, using a quaternary ammonium salt or a quaternary phosphonium salt having at least 3 alkyl groups each having at least 3 carbon atoms as a catalyst.

Abstract: A thermoplastic resin composition comprising a thermoplastic resin (A) and a thermoplastic polymer (B) having a glass transition temperature within the range of from -20.degree. C. to 70.degree. C. which are melt-blended in a proportion (A)/(B) of from 95/5 to 20/80 in weight ratio. The composition, upon application of an external stress in a temperature region of from a temperature about the glass transition temperature of the thermoplastic polymer (B) to the melting point thereof, is transformable to any shape that conforms to that stress, and is capable of becoming fixed to the transformed shape in a temperature region lower than the glass transition temperature.The composition can be used to provide a temperature-dependent shape-transformable/fixable product formed of the above composition.

Abstract: The present invention relates to a process for preparing a dispersion of high grade polyester copolymer resin in water comprising 1) combining a crude polyester copolymer resin, having particles of various sizes, with water; 2) heating and agitating the resin/water mixture; 3) cooling the mixture; 4) continuously filtering the mixture to remove the largest size resin particles; 5) allowing the mixture to stand undisturbed so that any undispersed particles settle out as a sediment; and 6) removing the sediment, leaving a dispersion of the smallest resin particles in water. By using a plurality of filters and sequentially finer filter mesh sizes, a high grade product is attained.

Abstract: Ethylenically unsaturated compounds are provided having Structure I and from which polymers with a plurality of groups of Structure II are derived. ##STR1## In Structures I and II, R.sub.1 is hydrogen or methyl, and R.sub.3 is hydrogen or lower alkyl having 1 to 4 carbon atoms, and when R.sub.3 is hydrogen and R.sub.2 has two carbon atoms R.sub.2 is methyl methylene. In Structure I, R.sub.2 and in Structure II R'.sub.2 is a divalent linking group having 2 to 20 carbon atoms. When R.sub.3 is hydrogen and R'.sub.2 has two carbon atoms, R'.sub.2 is methyl methylene. The compounds of Structure I may be used as monomers and reacted with other ethylenically unsaturated monomers via addition polymerization to arrive at the polymer with groups of Structure II.

Abstract: An improved process and apparatus for the production of a polyester or other condensation polymer is disclosed. In particular, polymerization is conducted in a reaction vessel equipped with a specially designed agitator that exposes the polymer melt partially filling the reaction vessel to inert gas flowing through the vessel. The agitator comprises a plurality of elements that lift a portion of a polymer melt in the reaction vessel and generate films of the polymer melt which films extends in planes that are parallel to the axis of the agitator and the flow of gas through the reaction vessel. In a preferred process, a melt of bis(2-hydroxyethyl) terephthalate, or its low molecular oligomers, obtained by esterifying terephthalic acid or transesterifying dimethyl terephthalate with ethylene glycol, is contacted with an inert gas at about atmospheric pressure in order to remove the reaction by-products and facilitate polymerization.

Abstract: A process for preparing a polyester which includes the step of heating a reaction mixture comprising (i) diesters of dihydric phenols and C.sub.1-10 aliphatic monoacids, (ii) aromatic dicarboxylic acids, and (iii) a catalytic amount of an organic cation-containing salt at a temperature above the melt temperature of the diesters, under reaction conditions sufficient to form the corresponding polyester. Use of this process subjects the polymers prepared thereby to a thermal history which causes relatively little deterioration of the polymer's properties.

Abstract: A process for preparing a thermoplastic hydroxy-functionalized polyesters comprises contacting a dicarboxylic acid or a mixture of dicarboxylic acids with a diepoxide in the presence of a monofunctional carboxylic acid and a catalyst, and in the absence of a solvent under conditions sufficient to form the hydroxy-functionalized polyesters.

Abstract: A laminated and insulated glass window construction, especially for use in entryway glass lites. The window includes first and second glass sheets mounted in facing, spaced apart relationship. An adhesive layer is disposed on an outer surface of the first glass sheet and a third glass sheet is adhered to the first glass sheet by the adhesive layer. A decorative element may be disposed within the space created between the first and second glass sheets. This decorative element may be a separate panel or a resinous layer adhered to an inside surface of one of the first and second glass sheets.

Abstract: A sulfonated dicarboxylic acid and a diaromatic carbonate are reacted by a solution process to form a sulfonated aromatic diester such as diphenyl sodium 5-sulfoisophthalate. The sulfonated aromatic diester is reacted with an aromatic polymer precursor mixture such as bisphenol A and diphenyl carbonate, polymer or combination thereof, at a temperature above the melting point of the polymer or a member of the aromatic polymer precursor to form a randomly positioned sulfonated aromatic moiety in a polymer chain of a thermoplastic non-crosslinked aromatic polymer such as a linear polycarbonate.

Abstract: Liquid crystalline polymers that are made from 4-hydroxybenzoic acid, 2,6-naphthalenedicarboxylic acid, terephthalic acid, hydroquinone, and N-acetyl-4-aminophenol by heating the monomers in the presence of acetic anhydride are more easily synthesized in high molecular weight if isophthalic acid is also included as a monomer at a level of about 0.5 mole % to about 10 mole %.

Abstract: A process for the preparation of polycarbonate copolyether diols comprising two successive reaction stages wherein in the first stage the precursor, bisdimethylcarbonate of polyether diols is synthesized by reacting, in a reactor equipped with a distillation column, one or more polyetherglycols with dimethyl carbonate, in the presence of a basic catalyst selected from the group consisting of an oxide, a hydroxide, a carbonate and an alcoholate of a metal belonging to the group of alkaline or earth-alkaline metals and in the second stage, the precursor, after being freed from the catalyst and excess dimethylcarbonate, is converted to polycarbonate copolyether diols by transesterification reaction with polyetherglycols in the presence of a solvent and an organometallic catalyst selected from compounds of tin, lead, titanium, zirconium and antimonium, said polycarbonate polyether diols having utility as additives in the field of polyurethane end-products, thermoelastomers, paints and adhesives.

Abstract: The present invention provides an amino curable polyester oligomer composition having low viscosity and a narrow molecular weight distribution comprising one or a mixture of oligomers (a) and (b): ##STR1## wherein R is the residue of at least one aliphatic, cycloaliphatic or mixed aliphatic/aromatic polycarboxylic-acid having from 2 to about 20 carbon atoms, R.sub.1 is the residue of at least one aliphatic, cycloaliphatic or mixed aliphatic/cycloaliphatic polyol having from 2 to about 20 carbon atoms, A is a radical of the formula: ##STR2## B is a radical of the formula: ##STR3## wherein R.sub.4 is H, OH, halogen or an organic radical containing 1 to 4 carbon atoms, R.sub.5 is a direct bond or an organic radical containing 1 to 20 carbon atoms and R.sub.6 is an organic radical containing 2 to 20 carbon atoms, n is a number averaging from greater than 0 up to less than 2 and p is a number averaging from about 0.

Abstract: To provide a flame-retardant polyester resin composition excellent in moldability and capable of keeping its excellent contact properties stable for a long period of time when it is molded into an electric component such as a relay or switch.100 parts by weight of a polyester resin (a) comprising as the main constituents an aromatic or aliphatic dicarboxylic acid and an aliphatic diol, each end of which is substituted with a monofunctional compound having a carboxyl or hydroxyl group, the amount of the hydroxyl end group being 40 meq/kg or below, is blended with 1 to 50 parts by weight of a specified halogenated phenoxy compound (B), 0.1 to 30 parts by weight of an antimony compound (C), and 0 to 150 parts by weight of an inorganic filler (D).

Abstract: A toner resin composition and a method of making the same are disclosed. The toner resin composition comprises a polyester resin formed from a reaction between a polybasic acid or anhydride and a polyhydric alcohol, and a polyfunctional epoxy resin which is crosslinked to the polyester resin. The crosslinking is effected in the presence of a catalyst.

Abstract: This invention relates to a method of melt processing a copolyester having a moisture content of 0.02 weight % or more comprising:(a) one or more dicarboxylic acids, and(b) a glycol component comprising from about 60 to 100 mole % 1,4-cyclohexanedimethanol.

Abstract: In the reflector according to the invention based on unsaturated polyester resins the surface of the unworked piece has an average surface peak-to-valley height of less than 0.5 .mu.m. It is produced by injection molding of a molding compound based on unsaturated polyester resins and subsequent application of a metal coating on that surface of the unworked piece which is to be reflecting wherein the polyester molding compound is free of fibers and styrene.

Abstract: Liquid-crystalline polymer blends comprising two or more cholesteric liquid-crystalline polymers or at least one nematic liquid-crystalline polymer and at least one cholesteric liquid-crystalline polymer.All hues can be produced specifically and in a reproducible manner by variation in the blend components and in the mixing ratio. The polymer blends are suitable as materials or as effect pigments.

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 polyester/polycarbonate (PES/PC) blend having enhanced properties as virgin material and as recyclate comprisesa) at least one phosphite,b) at least one sterically hindered phenol,c) at least one compound promoting the reaction of an epoxy resin with a PES/PC blend which is a Lewis base, andd) at least one difunctional epoxy resin, with 0.01 to 10 parts of component c) being used per 100 parts of PES/PC blend.

Abstract: A new process is provided for the formation of aromatic polyesters directly from the reaction of dialkyl ester of an aromatic carboxylic acid with dihydric phenols. The polycondensation is carried out in the presence of (a) a condensing agent; (b) a catalyst selected from the group consisting of derivatives of Group I metals, derivatives of Group IV A metals, derivatives of Group IV B metals, and mixtures thereof; and (c) a co-catalyst selected from the group consisting of methanesulfonic acid, sulfuric acid, p-toluenesulfonic acid, alkanoic acid having the formula, C.sub.n H.sub.x F.sub.y COOH, where n is an integer from 1 to 4, x and y are integers from 0 to 2n+1, and the sum of x and y is 2n+1, and mixtures thereof; at suitable temperature and pressure conditions and for a sufficient period of time to form the aromatic polyester.

Abstract: A process for preparing an esterification product is disclosed. The process comprises providing a polyfunctional organic acid or anhydride, a cyclic organic carbonate compound, and a catalyst selected from the group consisting of an alkali metal, an alcohol-derived salt of the alkali metal, and mixtures thereof, and reacting the polyfunctional organic acid or anhydride and the cyclic organic carbonate compound in the presence of the catalyst to form the esterification product.

Abstract: Liquid crystalline polyesters made from hydroquinone, terephthalic acid, 2,6-naphthalene dicarboxylic acid and 4-hydroxybenzoic acid, and having a selected composition range, have melting points of about 350.degree. C. or less, good physical properties, and are readily manufactured. The polymers are useful as molding resins.

Abstract: Poly(ester-imides) containing t-butylhydroquinone and trimellitic anhydride as part of the repeat units, as well as other monomers, are useful as molding resins. The polymers have a high glass transition temperature and are particularly useful in applications requiring good wear resistance.