Abstract: A thermotropic polyesterimide, in which the liquid-crystalline phase is of nematic structure within a useful temperature range, consists of units of formula: ##STR1## the units being in the following ratios:a/(b+c)=1c/b=0-50/50, and preferably c/b<30/70The polyesterimide of the present invention possesses self-reinforcement characteristics, or reinforcement characteristics for traditional thermoplastic materials.

Abstract: A thermotropic copolyester, which displays a liquid-crystal phase of nematic type, within a desired temperature range, contains units deriving from:(a) a saturated, aliphatic dicarboxy acid;(b) 4,4'-dihydroxy-biphenyl and/or mono- or di-alkyl- or -alkenyl-derivatives thereof;(c) 4-hydroxy-benzoic acid and/or alkyl- or alkenyl-derivatives thereof.Such a copolyester improves the processability of unsaturation-containing elastomers and enhances the mechanical properties of subsequently vulcanized products.

Abstract: An improved process for preparing carboxylated 2-allyl-phenols of general formula (I): ##STR1## is disclosed, which consists of a first step of simultaneous esterification and etherification of a carboxylated phenol, subsequent rearrangement of the resulting product to yield allyl-carboxylated allyl-phenol and end saponification of the latter into carboxylated 2-allyl-phenol.

Abstract: A thermotropic copolyesteramide, with a nematic structure of the liquid crystalline phase within a desired temperature range of the mesophase, contains a unit derived from: (a) a saturated .alpha., .omega.-dicarboxylic acid; (b) 4,4'-dihydroxydiphenyl; (c) p-aminobenzoic acid; (d) 2,6-dihydroxyriaphthoic acid.A copolyesteramide of this type exhibits improved characteristics, especially in regard to its elastic modulus and tensile strength, when used as a self-reinforced material or as a reinforcement material for traditional thermoplastic polymers.

Abstract: A thermotropic copolyesteramide, with a nematic structure of the liquid crystalline phase within a desired temperature range of the mesophase, contains metered amounts of units derived from: (a) a saturated aliphatic -dicarboxylic acid; (b) 4,4'-dihydroxydiphenyl; (c) 4-hydroxybenzoic acid and (d) 4-aminobenzoic acid or (d') 4-aminophenol.This thermotropic copolyesteramide, produced by the copolymerization of monomers in the molten state, is a material with self-reinforcing characteristics capable of yielding, by normal injection or extrusion processes, remarkable molecular orientations which impart a high rigidity to the manufactured products.The copolyesteramide may be used as a reinforcement material for traditional thermoplastic polymers, by usual techniques.

Abstract: Semi-aromatic copolyamides and copolyester-amides are obtained by placing an aliphatic polyamide into contact with an aromatic hydroxyacid or aminoacid, by operating at high temperature, under melting conditions, possibly in the presence of a catalyst, with a ratio of the monomer units of aliphatic polyamide to the mols of aromatic hydroxyacid or aminoacid comprised within the range of from 20:1 to 1:1.The semiaromatic copolyamides and copolyester-amides so obtained can display a thermotropic liquid-crystal behavior as a function of their content of aromatic units linked inside the molecular chain. Their elastic modulus results to be improved relatively to the alifatic polyamides used as the starting product, and the elongation at break results to be decreased.Such semiaromatic polyamides and copolyester-amides can find application in the production of high-stiffness articles, by means of moulding or extrusion processes.

Abstract: A hollow fiber of amorphous, hydroxy-ethylated poly-(2,6-dimethyl-p-oxyphenylene) (PPO-OH) with a glass transition temperature (Tg) of from 180.degree. to 200.degree. C. is disclosed, which is formed by a high-density, microporous layer on a macroporous backing, and having an outer diameter comprised within the range of from 450 to 550 .mu.m and an inner diameter comprised within the range of from 250 to 400 .mu.m.The process for preparing the hollow fibre and the use of said fibre in the processes of separation of gas mixtures are disclosed as well.

Abstract: A process for preparing a modified, amorphous poly-(2,6-dimethyl-p-oxyphenylene) (PPO) comprises:(a) metalating PPO with a metalating agent, and(b) functionalizing such a metalated PPO by reacting the PPO with a trialkylsilyl halide and/or ethylene oxide; and is characterized in that the reaction of metalation is carried out in an inert liquid vehicle which contains PPO in an at least partially suspended solid form, by operating under metalating conditions of gradually adding metalating agent to such a suspension, either continuously or as discrete portions. Depending on the functionalizing agents used, and on the sequence of addition thereof, the process makes it possible to obtain PPO polymers which are modified with trialkyl-silyl, hydroxyethylene and/or ethyleneoxytrialkyl-silyl functional groups. The modified PPO polymers are particularly suitable for preparing flat membranes, including asymmetrical membranes, for the separation of gas mixtures.

Abstract: A thermotropic copolyester, showing a liquid-crystalline structure of nematic type within a desired temperature range, contains umits deriving from:(a) a saturated bicarboxy aliphatic acid;(b) 4,4'-di-hydroxy-diphenyl,(c) 4-hydroxybenzoic acid; and(d) 4-hydroxy-benzoic acid bearing an alkyl substituent or a halogen atom bonded to the aromatic ring.Such a copolyester constitutes a material endowed with self-reinforcing characteristics, originating, through the usual transformation processes by injection or by extrusion techniques, marked molecular orientations, which supply the manufactured articles with high stiffness characteristics.Said material can be also used as a reinforcing agent when is mixed, by means of the usual techniques, with the traditional thermoplastic polymers.

Abstract: Semi-aromatic copolyamides and copolyester-amides are obtained by placing an aliphatic polyamide into contact with an aromatic hydroxyacid or aminoacid, by operating at high temperature, under melting conditions, possibly in the presence of a catalyst, with a ratio of the monomer units of aliphatic polyamide to the mols of aromatic hydroxyacid or aminoacid comprised within the range of from 20:1 to 1:1.The semiaromatic copolyamides and copolyester-amides so obtained can display a thermotropic liquid-crystal behaviour as a function of their content of aromatic units linked inside the molecular chain. Their elastic modulus results to be improved relatively to the alifatic polyamides used as the starting product, and the elongation at break results to be decreased.Such semiaromatic polyamides and copolyester-amides can find application in the production of high-stiffness articles, by means of moulding or extrusion processes.

Abstract: A thermotropic copolyester, showing a liquid-crystalline structure of nematic type within a desired temperature range, contains units deriving from:(a) a saturated bicarboxy aliphatic acid;(b) 4,4'-di-hydroxydipheryl;(c) 4-hydroxybenzoic acid; and(d) 4-hydroxy-benzoic acid bearing an alkyl substituent or a halogen atom bonded to the aromatic ring.Such a copolyester constitutes a material endowed with self-reinforcing characteristics, originating, through the usual transformation processes by injection or by extrusion techniques, marked molecular orientations, which supply the manufactured articles with high stiffness characteristics.Said material can be also used as a reinforcing agent when is mixed, by means of the usual techniques, with the traditional thermoplastic polymers.

Abstract: A thermotropic copolyester, having a liquid-crystallne mesophase of nematic structure within a desired range of temperatures, contains units derived from:(a) a saturated aliphatic bicarboxy acid;(b) 4,4'-dihydroxy-biphenyl;(c) p-hydroxybenzoic acid; and(d) 2,6-hydroxynaphthoic acid.Such a thermotropic copolyester displays improved characteristics, in particular as regards its extensional modulus and its tensile strength, when is used as a self-reinforced material, or as a reinforcer material for traditional thermoplastic polymers.

Abstract: Thermotropic copolyazomethines having a mesophase temperature range lying within a desired range of values are obtained by copolymerizing terephthalic aldehyde with at least two different 1,n-bis(4-aminophenoxy)alkanes.Such copolyazomethines are particularly useful as reinforcing materials for the usual thermoplastic polymers, such as polycarbonate, polybutyleneterephthalate, polyethyleneterephthalate and polyamides.

Abstract: A solid polymeric electrolyte is constituted by a solid solution of an ionic compound in a cross-linked polyether, wherein this latter is the copolymerization product of a vinyl-ether of formula:R--(O--CH.sub.2 --CH.sub.2).sub.n --O--CH.dbd.CH.sub.2 (I)wherein:R is the methyl or ehtyl radical; andn is an integer comprised within the range of from 1 to 16; with a di-vinyl-ether of formula:CH.sub.2 .dbd.CH--(O--CH.sub.2 --CH.sub.2).sub.m --O--CH.dbd.CH.sub.2(II)wherein:m is an integer comprised within the range of from 1 to 16; with a molar ratio of the di-vinyl-ether (II) to the vinyl-ether (I) comprised within the range of from 1/100 to 10/100; with said polyether having a weight average molecular weight of about 10,000, and a glass transition temperature (T.sub.g) comprised within the range of from --60.degree. C. to --80.degree. C.Such a solid polymeric electrolyte is used in the manufacturing of high-energy-density electrochemical generators.

Abstract: A thermotropic copolyester, having a nematic structure of the liquid-crystalline phase within a desired range of mesophase temperature, contains units derived from a saturated aliphatic dicarboxylic acid, 4,4'-dihydroxy-biphenyl and p-hydroxybenzoic acid, in a mutual ratio of from 1:1:0.5 to 1:1:8.This thermotropic copolyester is produced by copolymerizing in the molten state a saturated aliphatic dicarboxylic acid, 4,4'-diacyloxybiphenyl and p-acyloxybenzoic acid.The use is disclosed of the thermotropic copolyester as a self-reinforced material, and as a reinforcer material for such traditional thermoplastic polymers as polybutylene terephthalate, polyethylene terephthalate, polycarbonate and nylon.

Abstract: Novel polyacetylene films are disclosed, having the following properties:elongation at break (1/10): higher than 4tensile strength: higher than 100 MPaability of attaining under stretch high levels of molecular orientation in the direction of pull.The process for preparing such polyacetylene films is also described.

Abstract: A novel catalytic system is disclosed which is especially adapted for the polymerization and the copolymerization of aliphatic conjugated diolefines, the system comprising an organic compound of aluminum, a Lewis acid containing at least one halogen, and an organic compound of a lanthanide metal. The catalyst system has outstanding and hitherto unparalleled activity. The method of preparation of the catalytic system is also described in detail.