Abstract:
The invention relates to a process for preparing a salt from diamine and dicarboxylic acid, the process comprising contacting a diamine gas, having a gas temperature T-gas, with a dicarboxylic acid, thereby forming a reaction mixture comprising diamine/dicarboxylic acid salt, wherein the dicarboxylic acid and the reaction mixture are kept at a temperature T-mixture of at least 10° C. below the lowest of the melting temperature of the dicarboxylic acid (Tm-acid) and the melting temperature of the resulting diamine/dicarboxylic acid salt (Tm-salt). The invention also relates to a process for preparing a polyamide comprising preparing a salt from diamine and dicarboxylic acid.
Abstract:
The invention relates to a polyamide comprising units derived from: A. a diamine comprising in its structure at least one cyclohexane fragment according to Structure I, in which the substituents are in the 1,4-trans-position (Structure I), with n a positive integer of at least 1, and the proviso that when n is 2 or higher the cyclohexane rings are connected to each other through the 1,4-trans position, B. an aliphatic dicarboxylic acid with at least 13 carbon atoms and optionally comprising units derived from: C. one or more aliphatic dicarboxylic acids other than B, D. one or more diamines other than A, E. one or more monofunctional carboxylic acids or monofunctional amines, F. one or more polyfunctional monomers comprising carboxylic acid and/or amine groups, G. one or more lactams or corresponding amino acids. The invention further relates to a composition comprising such a polyamide and its uses.
Abstract:
The invention relates to a thermoplastic composition comprising (A) a semi-aromatic copolyamide comprising repeat units derived from diamine consisting primarily of tetramethylene diamine and hexamethylene diamine, or pentamethylene diamine and hexamethylene diamine, and dicarboxylic acid consisting primarily of terephthalic acid, having a VN of at least 100 ml/g; and (B) a reinforcing agent. The invention also relates to a plastic part made of the thermoplastic composition. The invention further relates to an automotive vehicle comprising a structural part made of the thermoplastic composition and to an electrical assembly comprising a plastic component made of the thermoplastic composition.
Abstract:
The present invention also relates to a process for preparing a diamine/dicarboxylic acid salt wherein the dicarboxylic acid comprises an aromatic dicarboxylic acid and is provided in a powder form; the diamine is provided in a liquid form gradually dosed to the dicarboxylic acid powder, while keeping the dicarboxylic acid powder in constant movement; the processing temperature is above 0° C. and below the boiling temperature of the diamine and the melting temperature of the acid and the salt, and the reaction mixture comprises at most 5 wt. % of water. The present invention also relates to an anhydrous diamine/dicarboxylic acid salt obtainable by the process according to invention, or any embodiment thereof as described above.
Abstract:
The invention relates to a flame retardant polyamide composition comprising (A) a polyamide polymer and (B) melam, wherein the polyamide polymer is a semi-crystalline semi-aromatic polyamide having a melting temperature of at least 270° C. and wherein the polyamide polymer has a carbon/nitrogen (C/N) ratio of at least 8. The composition shows reduced blooming.
Abstract:
The invention relates to an optically transparent polymer film or extrudate product made of a polymer composition comprising a semi-crystalline polyamide having a melting temperature of at least 270° C. or a blend of the semi-crystalline polyamide (A) and a second polymer (B), and optionally at least one additive, wherein the semi-crystalline polyamide (A) is present in an amount of more than 50 wt. %, relative to the total weight of the polymer composition, the polymer composition in the optically transparent polymer film or extrudate product has a melting temperature (Tm-C) in the range of 270-340° C., and wherein the film or a part of the extrudate product has a haze of less than 12% and a light transmittance, of at least 88% measured with the method according to ASTM D1003A.
Abstract:
Non-fibrous-reinforced thermoplastic molding compositions comprising a metal powder as a heat stabilizer are provided. The metal powder has a weight average particle size (dm) of at most 1 mm and the metal in the metal powder is selected from the group consisting of elementary metals from Group VB, VIB, VIIB and VIIIB of the Periodic Table, and mixtures thereof. A thermoplastic polyamide is also provided with an Mw of at most 50,000 g/mol, or a blend of at least two thermoplastic polymers with Tmelt or Tg differing by at least 20° C., or a second thermostabilizer. The invention also relates to the use of these compositions in high temperature applications.
Abstract:
The invention relates to a process for the preparation of semi-crystalline semi-aromatic polyamide by direct solid-state polymerization of a diamine-dicarboxylic acid salt, comprising steps of (a) providing at least two salts of terephthalic acid and diamine, wherein each of these diamine/terephthalic acid salts is in solid state and has a melting temperature of at least Tx, wherein Tx is at least 260° C.; (b) preparing a mixture of the diamine/terephthalic acid salts, while retaining the salts in solid state; and (c) heating the mixture obtained from step (b) in the solid state to a temperature (T-c) in the range from 200° C. to 260° C., under a pressure below the saturation vapor pressure of water at said temperature, thereby condensing and polymerizing the salts and forming a semi-crystalline semi-aromatic polyamide in solid form.
Abstract:
The invention relates to a polyamide comprising units derived from: A. a diamine comprising in its structure at least one cyclohexane fragment according to Structure I, in which the substituents are in the 1,4-trans-position (Structure I), with n a positive integer of at least 1, and the proviso that when n is 2 or higher the cyclohexane rings are connected to each other through the 1,4-trans position, B. an aliphatic dicarboxylic acid with at least 13 carbon atoms and optionally comprising units derived from: C. one or more aliphatic dicarboxylic acids other than B, D. one or more diamines other than A, E. one or more monofunctional carboxylic acids or monofunctional amines, F. one or more polyfunctional monomers comprising carboxylic acid and/or amine groups, G. one or more lactams or corresponding amino acids. The invention further relates to a composition comprising such a polyamide and its uses.
Abstract:
The invention relates to a process for the preparation of a semi-crystalline semi-aromatic polyamide copolymer (Co-PA) having a melting temperature (Tm-Co-PA) of at least 300° C., comprising steps of (a) preparing a first semi-crystalline semi-aromatic polyamide (A), having a melting temperature (Tm-A) of at least 310° C.; and consisting of repeat units derived from 45-50 mol % terephthalic acid; 47.5-50 mol % of diamine; and 0-5 mol % of one or more other amine and/or acid group containing components; the mol % being relative to the total molar amount of said amine and/or acid group containing components; and wherein poly-amide (A) is prepared by a process comprising direct solid-state polymerization of a diamine-dicarboxylic acid salt of the terephthalic acid and the diamine; (b) providing a polyamide (B), being an amorphous polyamide having a glass transition temperature (Tg-B) below Tm-A, or a second semi-crystalline polyamide having a melting temperature (Tm-B) below Tm-A, or a combination of the amorphous polyamide and the second semi-crystalline polyamide; (c) heating and melt-mixing polyamide (A) and polyamide (B), thereby obtaining a miscible polymer melt with a temperature (T-melt) above Tm-A; and (d) cooling the melt to a temperature below the solidification temperature of the melt, thereby obtaining a solid semi-crystalline semi-aromatic polyamide copolymer.