Abstract: A process for producing a copolymeric polyester, which comprises a first step of preparing a copolymeric oligomer by reacting a starting material oligoester or polyester having repeating units of the formula: ##STR1## wherein R.sub.1 is a divalent aromatic hydrocarbon group having from 6 to 10 carbon atoms, a divalent alicyclic hydrocarbon group having from 4 to 20 carbon atoms or/and a divalent aliphatic hydrocarbon group having from 1 to 40 carbon atoms (provided a hydrogen atom in the aromatic ring of the aromatic hydrocarbon group may be substituted by a halogen atom or an alkyl or alkoxy group having from 1 to 4 carbon atoms), and R.sup.

Abstract: Wholly aromatic polyesters which form a liquid-crystalline fiber-forming melt below 300.degree. C. and composed of(a) from 5 to 35 mol % of repeat units of the formula I ##STR1## (b) from 3 to 15 mol % of repeat units of the formula II ##STR2## (c) a molar amount corresponding to the total amount of (a) and (b) of repeat units of the formula III ##STR3## and (d) not less than 10 mol % of repeat units of the formula IV ##STR4## the molar proportions of components a, b, c and d adding up to 100 mol % in each case, the preparation thereof and fibers, films, moldings and surface coating materials prepared therefrom.

Abstract: Described herein are novel crystalline chain extended poly(aryl ether ketones) which display excellent toughness, fabricability and very good high temperature and solvent resistance.

Abstract: Wholly aromatic thermotropic polyesters are based on(A) from 25 to 60 mol % of a mixture of(A.sub.1) 4-hydroxybenzoic acid and(A.sub.2) 3-hydroxybenzoic acid, 4-aminobenzoic acid and/or 3-aminobenzoic acid or their chlorine, bromine, C.sub.1 -C.sub.8 -alkyl or C.sub.1 -C.sub.8 -alkoxy derivatives substituted in the nucleus,the molar ratio of A.sub.1 to A.sub.2 being from 5:1 to 41:1,(B) from 20 to 37.5 mol % of a mixture of(B.sub.1) terephthalic acid and(B.sub.2) isophthalic acid,the molar ratio of B.sub.1 to B.sub.2 being from 1.04:1 to 19:1, and(C) from 20 to 37.5 mol % of a mixture of(C.sub.1) hydroquinone and(C.sub.2) 4,4'-dihydroxydiphenyl,the molar ratio of C.sub.1 to C.sub.2 being from 0.1:1 to 2.67:1 and the molar ratio of B to C being from 0.9:1 to 1.1:1.

Abstract: A melt-moldable wholly aromatic polyester comprising (A) aromatic hydroxycarboxylic acid residues, (B) aromatic diol residues, (C) 4,4'-dihydroxydiphenyl ether residues represented by the following formula ##STR1## and (D) aromatic dicarboxylic acid residues, and a melt-moldable wholly aromatic polyester comprising (A) aromatic hydroxycarboxylic acid residues, (C)' aromatic diol residues represented by the following formula--O--Ar.sup.4 --O--wherein Ar.sup.4 represents a group at least 60 mole % of which consists of a group of the following formula (a) ##STR2## or a group of the formula (a) and a group of the following formula (b) ##STR3## and (D) aromatic dicarboxylic acid residues.

Abstract: Wholly aromatic mesomorphic polyether ester imides which form a liquid-crystalline fiber-forming melt below 320.degree. C. and are composed of(a) from 5 to 35 mol % of repeat units of the formula I ##STR1## (b) from 5 to 35 mol % of repeat units of the formula II ##STR2## where X is a chemical bond, --O--, --S--, --SO.sub.2 --, --CO--, --Ch.sub.2 -- or .dbd.C(CH.sub.3).sub.2, and n is 0 or 1,(c) from 15 to 30 mol % of repeat units of the formula III ##STR3## (d) a molar amount corresponding to the total amount of (b) plus (c) minus (a) of repeat units of the formulae IV and/or V ##STR4## (e) repeat units of the formula VI ##STR5## the mole percentages of components a, b, c, d and e adding up to a 100 mol % in each case,the preparation thereof and fibers, films and molding prepared therefrom.

Abstract: Fully aromatic themotropic polyesters are based on(A) from 30 to 60 mol % of 4-hydroxybenzoic acid,(B) from 20 to 35 mol % of a mixture of(B.sub.1) terephthalic acid and(B.sub.2) isophthalic acid,the molar ratio of B.sub.1 to B.sub.2 being from 1.04:1 to 19:1, and(C) from 20 to 35 mol % of a mixture of(C.sub.1) hydroquinone,(C.sub.2) 4,4'-dihydroxydiphenyl and(C.sub.3) from 0 to 5 mol % of a dihydroxy compound of the general formula I ##STR1## where R and R' are each C.sub.1 -C.sub.4 -alkyl, halogen or aryl, n is 1, 2 or 3 and m is 0 or 1,the molar ratio of C.sub.1 to C.sub.2 being from 0.1:1 to 2.67:1 and the molar ratio of B to C being from 0.9:1 to 1.1:1.

Abstract: A composition useful for molding into articles such as food containers, soft drink bottles, cured structural plastics and the like, comprising molding grade linear or unsaturated polyester or polycarbonate having reacted or copolymerized therein a total of from 100 to about 800 ppm, of the residue of one or a mixture of methine reactants of the formula ##STR1## wherein R.sup.1 is hydrogen or an unsubstituted or substituted alkyl, alkenyl, cycloalkyl or aryl radical;A.sup.1 is an unsubstituted or substituted phenylene radical;A.sup.2 is an unsubstituted or substituted 1,4-phenylene radical;R.sup.2 is hydrogen or an unsubstituted or substituted alkyl, cycloalkyl or aryl radical;R.sup.3 is cyano or ##STR2## and R.sup.4 is one of the substituents which R.sup.3 can represent or an unsubstituted or substituted carbamoyl, alkanoyl, aroyl, alkylsulfonyl, arylsulfonyl, aryl or aromatic heterocyclic radicals.

Abstract: A composition useful for molding into articles such as food containers, soft drink bottles, cured structural plastics and the like, comprising molding or fiber grade linear or unsaturated polyester or polycarbonate having copolymerized therein a total of from 1.0 to about 5,000 ppm, of the residue of one or a mixture of methine reactants of the formula ##STR1## wherein A is an unsubstituted or substituted 2-furanyl, 2-thienyl or 3-thienyl radical;R.sup.1 is hydrogen or a unsubstituted or substituted alkyl, cycloalkyl or aryl radical; andR.sup.2 is hydrogen or an unsubstituted or substituted alkyl, alkenyl, cycloalkyl or aryl radical.The methine residues are present in the polymer as an integral part of the polymer chain and absorb ultraviolet radiation in the range of about 150 to about 390 nm. The residues are non-extractable from the polymer and stable at the conditions at which the polymers are manufactured and processed.

Abstract: Fully aromatic mesomorphic polyesters which give a liquid crystalline filament-forming melt below 300.degree. C. consist of(a) from 5 to 25 mol % of repeating units of the formula I ##STR1## (b) from 5 to 25 mol % of repeating units of the formula II ##STR2## (c) from 10 to 50 mol % of repeating units of the formula III ##STR3## and (d) not less than 10 mol % of repeating units of the formula IV ##STR4## the sum of the molar amounts of components (a), (b), (c) and (d) being 100 mol %, and the molar ratio of components (a) and (b) to component (c) being from 0.9:1 to 1.1:1.

Abstract: Polyester polymers consisting essentially of repeating units having the formula ##STR1## repeating units having the formula--O--Ar.sup.1 --CO-- [II],repeating units having the formula--O--Ar.sup.2 --O-- [III],and repeating units having the formula ##STR2## wherein Ar.sup.1 is selected from ##STR3## Ar.sup.2 is selected from ##STR4## halogen substituted radicals of these radicals, and ##STR5## wherein X is selected from --O--, --S--, --SO.sub.2 --, --CO--, --O(CH.sub.2).sub.n O--.--CH.sub.2).sub.n, and ##STR6## wherein each n independently represents a member having a value of from 1 to 10, and each R.sup.4 is independently selected from alkyl radicals of 1 to 5 carbon atoms, andR.sup.2 and R.sup.3 are independently selected from hydrogen atom, halogen radicals, alkyl radicals of 1 to 5 carbon atoms, and phenyl radical, and R.sup.2 and R.sup.3 may be identical or different from each other, andR.sup.

Abstract: Composition useful for molding into articles which as food containers, beverage bottles, cured structural plastics and the like comprising molding grade linear or unsaturated polyester or polycarbonate having reacted therewith or copolymerized therein the residue of one or more poly-methine compounds having the formula: ##STR1## wherein each R.sup.1 is independently selected from cyano, carboxy, alkenyloxycarbonyl, or a substituted or unsubstituted alkoxycarbonyl, cycloalkoxoycarbonyl or aryloxycarbonyl radical;each R.sup.2 is independently selected from one of the groups specified for R.sup.1 or an unsubstituted or substituted aryl, carbamoyl, alkanoyl, cycloalkanoyl, aroyl, alkylsulfonyl, cycloalkylsulfonyl, arylsulfonyl or aromatic, heterocyclic radical;each R.sup.3 is independently selected from hydrogen or an unsubstituted or substituted alkyl, cycloalkyl or aryl radical;A.sup.1 and A.sup.

Abstract: Wholly aromatic, mesomorphic polyesters which give a homogeneous liquid crystalline melt at below 320.degree. C. consist of(a) not less than 10 mol % of repeating units of the formula I ##STR1## (b) from 1 to 25 mol % of repeating units of the formula II ##STR2## (c) from 5 to 20 mol % of one or more of the repeating units of the formulae III to VII ##STR3## (d) from 5 to 15 mol % of repeating units of the formula VIII ##STR4## and (e) from 10 to 60 mol % of repeating units of the formula IX ##STR5## the sum of the molar amounts of (a), (b), (c), (d) and (e) being 100 mol % in each case and the molar ratio of the components (b)+(c)+(d) to component (e) being from 0.9:1 to 1.1:1.

Abstract: Fully aromatic thermotropic polyesters are based on(A) from 30 to 60 mol % of 4-hydroxybenzoic acid,(b) from 20 to 35 mol % of a mixture of(B.sub.1) terephthalic acid and(B.sub.2) isophthalic acid,the molar ratio of B.sub.1 to B.sub.2 being from 1.04:1 to 19:1, and(C) from 20 to 35 mol % of a mixture of(C.sub.1) hydroquinone,(C.sub.2) 4,4'-dihydroxydiphenyl and(C.sub.3) from 0.5 to 5 mol % of(C.sub.31) 2,7-dihydroxynaphthalene and/or(C.sub.32) 1,3-dihydroxybenzene and/or(C.sub.33) and aromatic dihydroxy compound of the general formula I ##STR1## where X is --CH.sub.2 --, --C(CH.sub.3).sub.2 --, --S--, --SO.sub.2 --, --O-- or --CO--, and/or(C.sub.34) a compound of the general formula II ##STR2## where Y is NH.sub.2 or OH, the molar ratio of C.sub.1 to C.sub.2 being from 0.1:1 to 2.67:1 and the molar ratio of B to C being from 0.9:1 to 1.1:1.

Abstract: A melt-processable copolyester composed of the following structural units (I), (II) and (III) and/or (IV) as main structural components, whereinunit (I) is represented by the formula ##STR1## wherein X.sub.1, X.sub.2, X.sub.3 and X.sub.4, independently from each other, represent H, F, Cl, Br, CH.sub.3 or C(CH.sub.3).sub.3, provided that X.sub.1 to X.sub.4 do not simultaneously represent H, and n is 2 or 4,unit (II) is at least one unit selected from the group consisting of ##STR2## wherein at least one of the hydrogen atoms in each aromatic ring in units (II), (III) and (IV) may be substituted by an alkyl or alkoxy group having 1 to 4 carbon atoms or a halogen atom.The proportion of unit (I) is 2.5 to 35 mole %, the proportion of unit (II) is 2.5 to 35 mole %, and the proportion of unit (III), (IV) or a combination of units (III) and (IV) is 30 to 95 mole %.

Abstract: Novel copolyesters derived from (a) aromatic diols, (b) dicarboxylic acids and (c) aromatic hydroxycarboxylic acids, in which the aromatic hydroxycarboxylic acid component (c) comprises 20 to 60 mole % of the copolyester and in which t-butyl-4-hydroxybenzoic acid constitutes 25 to 100 mole % of the aromatic hydroxycarboxylic acid component (c), are disclosed. These copolyesters are anisotropic and fabricable in the melt. They generally can be processed using conventional thermoplastic shaping techniques at temperatures below 350.degree. C. into moldings, fibres and films which have outstanding mechanical properties.

Abstract: A cholesteric liquid crystal polyester consisting essentially of the following structural units (A), (B), (C) and (D): ##STR1##

Abstract: The novel polyester of the present invention is capable of forming a highly tractable anisotropic melt phase. Such polyester includes a relatively low concentration of 6-oxy-2-naphthoyl moiety in combination with a more substantial concentration of 4-oxybenzoyl moiety. Other key moieties present are, 2,6-dioxynaphthalene moiety and terephthaloyl moiety. The polyester can be formed via a melt polymerization procedure to achieve a relatively high degree of polymerization in view of its relatively low melt viscosity. The polyester upon melt extrusion forms quality high performance fibers, films, and three-dimensional shaped articles. The resulting product also well retains desirable mechanical properties at elevated temperatures.

Abstract: The invention relates to new aromatic polyesters based on terephthalic acid and hydroquinones, processes for their preparation from hydroquinone and terephthalic acid derivatives, and their use for the preparation of molecularly reinforced polymers.

Abstract: The production of oxybenzoyl polyesters is facilitated by the incorporation of a salt, particularly an alkali earth metal salt, and preferably potassium sulfate, during the production enabling the consistent production from these polyesters of molded articles of improved appearance and excellent properties.

Abstract: A cholesteric liquid crystal polyester consisting essentially of structural units represented by the following formulae (A), (B) and (C): ##STR1## which is optically active; and ##STR2## wherein X is hydrogen, halogen, or alkyl having not more than four carbon atoms.

Abstract: An aromatic copolyester comprising substantially equimolar proportions of [A] units derived from an aromatic dicarboxylic acid having 8 to 16 carbon atoms, and [B] units derived from an aromatic diol component; characterized in that(I) the diol component [B] is composed of 20 to 95 mole %, based on the total moles of compounds (a) and (b) below, of(a) a bisphenol compound represented by the formula ##STR1## wherein X represents a direct bond, or a divalent group selected from the class consisting of C.sub.1 -C.sub.8 alkylidene groups, O, S, SO, SO.sub.2 and CO, and(b) 5 to 80 mole %, based on the total moles of the compounds (a) and (b), of a compound selected from the group consisting of a specific divalent phenolic compound, and(II) the aromatic copolyester has an intrinsic viscosity [.eta.], determined at 60.degree. C. in pentafluorophenol, of at least 0.4 dl/g.

Abstract: Wholly aromatic mesomorphic polyester imides which form a liquid-crystalline fiber-forming melt below 320.degree. C. and are composed of(a) from 5 to 35 mol % of repeat units of the formulae I and/or II ##STR1## where x can be identical or different and each is --O--, --S--, --SO.sub.2 --, --CO--, --CH.sub.2 -- or .dbd.C(CH.sub.3).sub.2, and n is 1 or 2,(b) from 0 to 30 mol % of repeat units of the formulae III and/or IV ##STR2## (c) a molar amount corresponding to the total amount of components (a) and (b) of repeat units(c1) from 3 to 35 mol % of units of the formula V ##STR3## and one or more of the repeat units.

Abstract: Wholly aromatic mesomorphic polyester imides which form a liquid-crystalline fiber-forming melt below 320.degree. C. and are composed of(a) from 5 to 35 mole % of repeat units of the formulae I and/or II ##STR1## where the Xs and n's can be identical or different, each X being --O--, --S--, --SO.sub.2 --, --CO--, --CH.sub.2 -- or .dbd.C(CH.sub.3).sub.2 and n being 0 or 1,(b) from 0 to 30 mole % of repeat units of the formulae III and/or IV ##STR2## (c) a molar amount corresponding to the total amount of components a and b of one or more of the repeat units of the formulae V, VI, VII or VIII ##STR3## (d) not less than 10 mole % of repeat units of the formula IX ##STR4## (e) if desired from 5 to 25 mole % of repeat units of the formula X ##STR5## the molar proportions of components a, b, c, d, and e adding up to 100 mole % in each case,and the preparation thereof.

Abstract: Wholly aromatic polyesters which form a liquid-crystalline fiber-forming melt below 300.degree. C. and are composed of(a) from 10 to 25 mol % of repeat units of the formula I ##STR1## (b) from 5 to 15 mol % of repeat units of the formula II ##STR2## (c) from 5 to 15 mol % of repeat units of the formula III ##STR3## (d) not less than 10 mol % of repeat units of the formula IV ##STR4## and (e) a molar amount corresponding to the total amount of (a), (b) and (c) of repeat units of the formula V ##STR5## the molar proportions of components a, b, c, d and e adding up to 100 mol % in each case, the preparation thereof and fibers, films, moldings and surface coatings prepared therefrom.

Abstract: Wholly aromatic mesomorphic polyester amide imides which form a liquid-crystalline fiber-forming melt below 320.degree. C. and are composed of(a) from 5 to 35 mol % of repeat units of the formula I and/or II ##STR1## where X can be identical or different, each X being --O--, --S--, --SO.sub.2 --, --CO--, --CH.sub.2 -- or .dbd.C(CH.sub.3).sub.

Abstract: Wholly aromatic mesomorphic polyester amides which form a liquid-crystalline fiber-forming melt below 320.degree. C. and are composed of(a) from 5 to 35 mol % of repeat units of the formula I ##STR1## (b) from 5 to 15 mol % of repeat units of the formula II ##STR2## (c) a molar amount corresponding to the total amount of components (a) and (b), and, when (e) signifies repeat units of the formula VI or VII, (e) of repeat units of the formula III ##STR3## (d) not less than 10 mol % of repeat units of the formula IV ##STR4## (e) from 2 to 15 mol % of repeat units of the formula V ##STR5## or of the formula VI ##STR6## the repeat units of the formula VI being replaceable in part by repeat units of the formula VII ##STR7## with the proviso that the molar proportions of components (a), (b), (c), (d) and (e) add up to 100 mol % in each case, the preparation thereof and fibers, films, molding and surface coating materials prepared therefrom.

Abstract: Wholly aromatic mesomorphic polyester amides which form a liquid-crystalline fiber-forming melt below 320.degree. C. and are composed of(a) from 3 to 30 mol % of repeat units of the formula ##STR1## (b) from 3 to 25 mol % of one or more of the repeat units of the formulae II, III and IV ##STR2## (c) a molar amount corresponding to the total amount of components (a) and (b) of repeat units of the formulae V and/or VI ##STR3## (d) repeat units of the formula VII ##STR4## (e) if desired from 5 to 25 mol % of repeat units of the formula VIII ##STR5## the mole percentages of components (a), (b), (c), (d) and (e) adding up to 100 mol % in each case, and the preparation and use thereof.

Abstract: Described herein is an improved process for preparing poly(aryl ether ketones) by reacting nucleophilic coreactants with electrophilic coreactants under Friedel Crafts polymerization conditions, wherein the improvement comprises carrying out the polymerization in a solvent comprising 1,2-dichlorethane.

Abstract: A process for producing an aromatic polyester by polycondensation of either(1)(a) aromatic hydroxycarboxylic acids containing at least 50 mole % of p-hydroxybenzoic acid, and/or ester-forming derivatives of these acids,(b) an aromatic dicarboxylic acid and/or an ester-forming derivative of aromatic dicarboxylic acid, and(c) an aromatic dihydroxy compound and/or an ester-forming derivative of aromatic dihydroxy compound,wherein the (a):(b) molar ratio and the (a):(c) molar ratio are each from 1:0 to 1:4, or(2)(d) aromatic dicarboxylic acids containing at least 50 mole % of terephthalic acid, and/or ester-forming derivatives of these acids and(e) aromatic dihydroxy compounds containing at least 50 mole % of at least one of hydroquinone, substituted hydroquinone, 4,4'-dihydroxydiphenyl, and substituted 4,4'-dihydroxydiphenyl, and/or ester-forming derivatives of these dihydroxy compounds,characterized in that the polycondensation is carried out by using a liquid compound which has a higher boiling point at normal

Abstract: Described herein is a process for stabilizing a poly(aryl ether ketone) produced by a Friedel-Crafts polymerization process which comprises adding a nucleophilic and/or an electrophilic capping agent during the polymerization.

Abstract: High molecular weight thermotropic aromatic polyesters having flow temperatures ranging from 200.degree. to 350.degree. C., and well adopted for molding into mechanically improved shaped articles, e.g., fibers and films, are comprised of recurring structural units of the formulae (I), (II), (III) and (IV), wherein (I) is the structural unit: ##STR1## in which R.sub.1 is methyl, ethyl, chlorine or bromine, said structural units (I) either being identical or different; (II) is the structural unit: ##STR2## (III) is the structural unit: ##STR3## (IV) is the structural unit: ##STR4## and further wherein the molar ratio of the structural units (I) relative to the total amount of the structural units (II)+(III) ranges from 0.95 to 1.

Abstract: Novel copolyetherketones derived from diphenyl ether and aromatic diacids or diacid halides are disclosed where the diphenyl ether is present in a molar excess relative to the diacid or diacid halide chlorides of about 2 to 8%.

Abstract: A thermoplastic polyester-carbonate resin containing in the polymer chain, divalent moieties of the formula: ##STR1## wherein R represents aliphatic hydrocarbyl of from 1 to 9 carbon atoms, inclusive, halogen substituted aliphatic hydrocarbyl of 1 to 9 carbon atoms, inclusive, aralkyl of 7 to 10 carbon atoms, inclusive and halogen substituted aralkyl of 7 to 10 carbon atoms, inclusive; a and b are each whole number integers of from 0 to 1; and the sum of a+b is 1 and wherein there are sufficient linkages of formula I to lower the glass transition temperature of the polymer.

Abstract: Thermotropic aromatic polyesters which contain 3,3'-diphenyl-4,4'-dihydroxydiphenyl radicals as diphenol radicals can be processed by thermoplastic methods without decomposition, in spite of the high heat distortion resistance.

Abstract: A process for preparing a cholesteric liquid crystal copolyester consisting essentially of structural units represented by the following formula (A), (B), (C) and (D): ##STR1## which is optically active characterized in that a polyethylene terephthalate oligomer having a (B)/(A) mole ratio in the range of 1.1 to 1.8, p-acetoxybenzoic acid and 3-methyladipic acid are reacted to prepare the final cholesteric liquid crystal copolyester having an inherent viscosity of at least 0.4 dl/g.

Abstract: A five-component copolyester not described in the prior art literature which comprises at least five components, i.e. (a) two aromatic dicarboxylic acid components composed of a major amount of an isophthalic acid component and a minor amount of another dicarboxylic acid component, (b) a diol component composed of an ethylene glycol component and optionally another diol component, (c) an aromatic monohydroxy-monocarboxylic acid component and (d) a polyfunctional compound component having at least three functional groups. The copolyester has excellent melt moldability, mechanical strength, transparency and gas-barrier property in a well balanced combination, and shows improved properties over conventional copolyesters containing a major amount of isophthalic acid as a dicarboxylic acid component.

Abstract: Radiation sterilizable polymeric materials, particularly radiation sterilizable absorbable, surgical products made from such polymeric materials.

Abstract: Described herein are novel crystalline chain extended poly(aryl ether ketones) which display excellent toughness, fabricability and very good high temperature and solvent resistance.

Abstract: Wholly aromatic polyesters having improved mechanical properties are produced by polycondensing a raw material or raw material mixture capable of forming an aromatic polyester and not more than about 18 mole %, based on the total amount of the entire raw materials, of 2-hydroxynaphthalene-6-carboxylic acid or its derivative.

Abstract: A process comprising synthesizing a liquid crystal polyester consisting essentially of recurring moieties of formulas: ##STR1## and moiety III or IV wherein III is ##STR2## wherein the mole ratio of moiety II to moiety III, when present, is 1:4 to 2:1 and wherein the mole ratio of moiety II to moiety IV, when present, is 2:8 to 1:9 and devolatilizing said liquid crystal polyester prior to shaping such polyester into an article and then shaping said devolatilized polyester into said article.

Abstract: Fully aromatic polyesters which contain 3-phenyl-4,4'-dihydroxybenzophenone radicals and/or 3-phenyl-3',4-dihydroxybenzophenone radicals as condensed units possess high mechanical properties but can still be processed without difficulties by a thermolastic method.

Abstract: Novel copolyesters derived from (a) aromatic diols, (b) dicarboxylic acids and (c) aromatic hydroxy carboxylic acids, in which t-butylhydroquinone constitutes 55 to 95 mole % of the diol component (a) are disclosed. These copolyesters are anisotropic and fabricable in the melt. They generally can be processed using conventional thermoplastic shaping techniques at temperatures below 350.degree. C. into moldings, fibers and films which have outstanding mechanical properties.

Abstract: The preparation of poly(arylene ketones) and in particular all para-linked poly(arylene ether ketones) by Friedel-Crafts polymerization in the presence of a Lewis acid generally results in an intractible reaction product difficult to remove from the reaction vessel and difficult to purify. The addition of a liquefaction agent, such as a hydrogen halide and in particular hydrogen chloride, to the reaction mixture, results in a tractible gel or a liquid which can be readily handled. The hydrogen halide is preferably under pressure and a diluent may also be added along with the hydrogen halide.

Abstract: An aromatic polyester comprising the following structural units [(I)+(II)], (I)+(II)+(III)], [(I)+(II)+(IV)], [(I)+(III)+(IV)], or [(I)+(II)+(III)+(IV)], the unit (I) occupying 20-85 mol % of all structural units, and a shaped article of a high elastic modulus obtained from the polyester: ##STR1## wherein R.sub.1 represents one or more groups selected from ##STR2## and R.sub.

Abstract: Polyarylates having amide terminal groups are prepared using a terminating amount of ammonia, ammonium compounds, primary amines, secondary amines, hydrogen ammonium salts of secondary amines, or hydrogen ammonium salts of primary amines. These amide terminated polyarylates exhibit improved thermal properties and are useful in the production of films and molded articles.

Abstract: The invention relates to completely aromatic polyesters in which at least one end of the molecular chains is composed of the radicals ##STR1## The invention also relates to a process for the preparation of polyesters of this type and to the shaped articles produced therefrom.The polyesters according to the invention are also open to subsequent solid-phase condensation.

Abstract: A process for forming polyesters with reduced yellow coloration wherein the polyester-forming monomers are dried in a vacuum before being reacted. The reaction system itself contains a substantially deoxygenated atmosphere. The removal of oxygen from the reactants and the reaction system leads to the lessening of yellow coloration of the polyester product.

Abstract: Polyesters having at least 90%, by weight, of recurrent structural units corresponding to the following formula: ##STR1## and characterised by a relative viscosity.eta..sub.rel of from 1.6 to 4.5 (determined at 25.degree. C. in CH.sub.2 Cl.sub.2, c=5 g/l) are suitable for the production of films having highly advantageous performance characteristics, in particular high heat resistance.

Abstract: Linear, melt processable, crosslinkable, thermotropic wholly aromatic ("liquid crystal") polyesters are prepared by polymerizing difunctional stilbene or tolan derivatives as comonomers with non-ethylenically and non-acetylenically unsaturated aromatic diols, dicarboxylic acids, hydroxy acids or reactive derivatives thereof. Shaped structures made from these polyesters are crosslinked using electron-poor monomers, such as maleic anhydride.