Abstract: The invention relates to a process for preparing a high-molecular polyamide or polyester by melt-mixing polyamide or polyester having a lower molecular weight with a carbonyl bislactam having formula 1, in which n=an integer of between 3 and 15. With the process according to the invention a permanent increase in the molecular weight of a polyamide is obtained within 2 minutes, whereas this takes at least 10 minutes under comparable conditions using a bislactam according to the state of the art.

Abstract: Polyhydroxyamides are polymerized to form highly-crosslinked, temperature-stable polymers. The polyhydroxyamides include as their central, parent structure a benzenetricarboxylic acid to which side chains containing a terminal reactive group are attached by an amide bond. By way of this reactive group, highly crosslinked polymers can be formed. In addition, the polyhydroxyamide can be added as an additive to polymers in order to bring about three-dimensional crosslinking.

Abstract: The invention relates to a semi-aromatic polyamide containing at least tetramethylene terephthalamide units and also hexamethylene terephthalamide units. The copolyamide has a melting point higher than approximately 290° C., a high crystallinity and a good stability. Preferably the copolyamide according to the invention contains approximately 30-75 mol % hexamethylene terephthalamide units and also approximately 0.01-20 mol % other units. The invention also relates to a process for the preparation of a semi-aromatic copolyamide containing at least tetramethylene terephthalamide units and hexamethylene terephthalamide units, characterized in that, successively, a first polymerization is effected in the melt phase, followed by an post-polymerization of the low molar mass polymer thus obtained in the solid phase; and to compositions and products that contain said copolyamide.

Abstract: The present invention relates in general to implantable, resorbable copolymers containing L-lactide and glycolide repeat units, and in particular to terpolymers containing L-lactide, glycolide, and one other type of repeat unit selected from the group consisting of D-lactide, D,L-lactide, and &egr;-caprolactone. Medical devices for in vivo implantation applications containing such implantable, resorbable copolymers are also described, as well as methods for making such copolymers and devices.

Abstract: The present invention is directed to a method for reducing waste accumulation by using an environmentally degradable disposable material. The disposable material, which includes a hydroxycarboxylic acid-containing polymer, degrades hydrolytically during operative and disposal stages in a controlled manner such that the disposal degradation rate of the material is accelerated relative to the operative degradation rate of the material.

Abstract: An alkyldiamine having excellent polymerization reactivity, a polyimide comprising it as a constituting element, and a liquid crystal alignment film excellent in uniformity of liquid crystal alignment, are presented. Namely, the present invention relates to a diaminobenzene derivative represented by the following general formula (1) and to a polyimide obtained by reacting a diamine containing at least 1 mol % of the diaminobenzene derivative represented by the general formula (1), with at least one compound selected from a tetracarboxylic. dianhydride and its derivatives, to obtain a polyimide. precursor having a reduced viscosity of from 0.05 to 5.0 dl/g (in N-methylpyrrolidone at a temperature of 30° C., concentration: 0.5 g/dl) and ring-closing it, and having a repeating unit represented by the general formula (2). Further, the present invention relates to a liquid crystal alignment film containing at least 1 mol % of the above repeating unit.

Abstract: The aromatic diamine compound of the present invention is represented by the following formula (1), and from the aromatic diamine compound a polyimide having a repeating unit represented by the following formula (4), which has low-temperature adherability, can be obtained. In the formulas (1) and (4), n is an integer of 3 to 7, each R is independently an atom or a group selected from the group consisting of a hydrogen atom, a halogen atom and a hydrocarbon group, the same or different two hetero atoms selected from nitrogen atoms and oxygen atoms bonded to each benzene ring are at the ortho- or meta-positions to each other on at least one benzene ring, and when n is 3, the hetero atoms are at the ortho- or meta-positions to each other on all the benzene rings. In the formula (4), Y is a tetravalent organic group.

Abstract: Process for the preparation of copolymeric polypeptides, which comprises, in a first stage, reacting glutamic acid and/or derivatives thereof with amines in the absence of solvents and catalysts, under condensation conditions and, in a second stage, adding one or more further amino acids and/or derivatives thereof and/or one or more identical and/or further amines simultaneously or in any desired order, and reacting them with the reaction product of the first stage in the absence of solvents and catalysts.

Abstract: A method for preparing a wide range of substituted poly(aniline)s from a single precursor is described. The method uses a variety of reactions, including a boron activation/electrophilic displacement reaction resulting in ipso-substitution. The ability to tune the properties of poly(aniline) through the generation of new structures is useful in numerous fields ranging from polymer-based electronics to sensors.

Abstract: A process for using low-molecular weight compounds that are water-extracted from (co)polyamides in the production of polyamide is disclosed. The process entails reacting these compounds with 10 to 15 wt. % water for a period of 3.5 to 6 hours at a temperature of 220° C. to 270° C., and polymerizing the resulting product along with caprolactam.

Abstract: A solvent-free, catalyst-free and contamination-free method of synthesis of polyimides is disclosed. The method includes polymerizing a diamine with 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride (6FDA) at a pressure of 0.1-760 mm Hg, preferably a reduced pressure at about 36 mm Hg, and a temperature of 90-400° C., preferably 10-240° C.

Abstract: An electrically conductive thermoplastic composition with a superior ability to be heated rapidly in an electromagnetic field comprises a polyetherimide resin, a polyester resin, and electrically conductive filler. Such compositions display good dimensional stability at elevated temperatures especially when heated rapidly using electromagnetic radiation, which renders them useful in articles and operations where rapid assembly is important.

Abstract: The invention is a polyimide, random copolymer having repeating units of the formula (1): wherein R1 and R2 each represent a divalent group selected from and R1 and R2 may be the same or different; and x=0.60 to 0.80, y+z=0.40 to 0.20, and x+y+z=1.00, and a linear expansion coefficient at 100 to 200° C. is in the range of from 10 to 20 ppm/K. This is a useful polyimide that can be a polyimide circuit substrate material capable of keeping flat, neither shrinking nor expanding in its laminate.

Abstract: An acid-dyeable polymer composition comprising (a) polymer and (b) polymeric additive comprising repeating units having the formula: or salts thereof, wherein A, B and Q, which may be the same or different, are selected from aliphatic or aromatic substituents provided that at least four carbon atoms separate any two nitrogen groups, R is an aliphatic or aromatic group, a is 1 to 5, and n is 3 to about 1,000. In addition, an acid-dyed composition prepared from the composition, a process of acid dyeing the composition and a process for preparing the composition.

Abstract: A heat-resistant resin film having a metallic thin film accumulated thereon or an endless belt having a metallic thin film accumulated thereon having good mechanical characteristics is produced in a simple process. A metallic thin film is formed on an inner surface of a cylindrical substrate, and a layer of a heat-resistant resin is formed thereon. An accumulated body of the heat-resistant resin and the metallic thin film is peeled off from the substrate. The metallic thin film may be formed by electroplating, electroless plating or vapor deposition, or may also be formed by attaching a metallic foil having been prepared on an inner surface of the substrate. The heat-resistant resin layer is formed by injecting a polyamide acid solution in a rotational drum, and then formed by centrifugal forming by rotating the rotational drum on rollers under heating. After forming, imidization is conducted by heating and baking to form a film member of a thermosetting polyimide.

Abstract: The invention relates to a method for treating plastic material, especially polyethylene terephthalate, wherein the relatively low temperature material is initially crystallized by heating before subjecting said material to heating or condensation in the solid phase. The material is then exposed to a hot treatment gas for at least 10 minutes in at least two chambers (2) of an apparatus and crystallized at a temperature above 135° C., e.g. 140-180° C. The is subsequently heated in a preheating chamber (3) having at least one to eight stages at a temperature of at least 185° C., preferably at least 200° C. and more preferably around 220° C.

Abstract: A process for the preparation of a reactive friable polyimide powder comprises dissolving an aromatic dianhydride and an organic diamine in a high-boiling, aprotic organic solvent to form a reaction solution; heating the reaction solution under imidization conditions to form an insoluble reactive polyimide and to effect substantially complete distillation of the water of reaction out of the reaction solution; and separating the insoluble reactive polyimide from the reaction solution to form a reactive friable polyimide powder.

Abstract: The present invention relates to a method of producing high-density polyidimide (HPI) films and its production equipment. The production equipment comprises a raw material supplying means, a vacuum cavity, an energy supplier, a clad laminator, and a baked solidified polymer. The foregoing components constitutes the production equipment, using the monomer with the CONH bond or copolymer as raw materials to extract the unsaturated C═N bond by heat, electrons, light, radiation rays or ions as energy under low-pressure environment, so that the H in vacuum can extract the non-solidified HPI film from the electronic radical covalent polymers and via heat or light to rearrange the structure into a solidified HPI film. By means of the method according to the present invention, the original HPI that is not easily to produce as a film can be easily made in form of a film of HPI polymer on the clad laminator.

Abstract: The present invention relates to thermoplastic film structures having improved barrier and/or mechanical properties and methods for making the film structures. These improvements are achieved by incorporating into the thermoplastic film structures a polymeric nanocomposite comprising a polymer and nanosize particles of a modified clay.

Abstract: Disclosed are a polyamic acid having repeating units represented by the formula (1): wherein the norbornane skeleton of comprises four components of and their contents satisfy the following: 1%≦2,5-[diexo]≦90%, 1%≦2,5-[exo,endo]≦90%, 1%≦2,6-[diexo]≦90%, 1% ≦2,6-[exo,endo]≦90%, provided that (2,5-[diexo])+(2,5-[exo,endo])+(2,6-[diexo])+(2,6-[exo,endo])=100%, R represents from 4 to 27 carbon atoms, and represents a tetravalent group selected from the group consisting of an aliphatic group, a monocyclic aliphatic group, a condensed polycyclic aliphatic group, a monocyclic aromatic group, a condensed polycyclic aromatic group, and a non-condensed polycyclic aliphatic or aromatic group which is composed of cycloaliphatic or aromatic groups mutually bonded to each other either directly or via a crosslinking member; and a polyimide