摘要:
The invention relates to thermoplastic molding compositions comprising the following components: A) at least one thermoplastic polyamide, B) at least one hyperbranched polyetheramine, C) at least one amorphous oxide and/or oxide hydrate of at least one metal or semimetal with a number-average diameter of the primary particles of from 0.5 to 20 nm. The invention further relates to the use of the components B) and C) mentioned, for improving the flowability and/or thermal stability of polyamides, to the use of the molding compositions for the production of fibers, of foils, and of moldings of any type, and also to the resultant fibers, foils, and moldings.
摘要:
Mixtures comprising linear block copolymers made from vinylaromatic monomers and from dienes of the structure (I) S1—B1—S2 and (II) S3—B2—S4, where S1 is a block made from vinylaromatic monomers with number-average molar mass Mn in the range from 40,000 to 100,000 g/mol, each of S2, S3 and S4 is a block made from vinylaromatic monomers with number-average molar mass Mn in the range from 5,000 to 20,000 g/mol, each of B1 and B2 is a block made from dienes or a copolymer block made from dienes and from vinylaromatic monomers with number-average molar mass Mn in the range from 15,000 to 40,000 g/mol, and the ratio of the block copolymers (I)/(II) is in the range from 0.6 to 2.
摘要:
The present invention relates to a process for preparing a polyamide based on dicarboxylic acids and diamines, comprising the following stages: A) providing an aqueous monomer mixture composed of dicarboxylic acids and diamines, where the molar ratio of dicarboxylic acids to diamines is adjusted such that, at the outlet of stage C), there is a molar deficiency of dicarboxylic acids or diamines of 1 to 10 mol %, based on the respective other component, B) transferring the aqueous mixture from stage A) into a continuous evaporator reactor in which diamines and dicarboxylic acids are converted at a temperature in the range from 100 to 370° C. and a pressure in the range from 1 to 50 bar, C) transferring the mixture from stage B) into a separator which is operated at a temperature in the range from 100 to 370° C. and a pressure in the range from 1 to 50 bar with removal of gaseous components, D) transferring the mixture from stage C) together with diamine or dicarboxylic acid in an amount suitable for compensation for the molar deficiency into a tubular reactor which is operated at a temperature in the range from 100 to 370° C. and a pressure in the range from 1 to 50 bar, for a residence time in the range from 10 seconds to 30 minutes, E) transferring the mixture from stage D) into an extruder which is operated at a temperature in the range from 150 to 400° C. for a residence time in the range from 10 seconds to 30 minutes with removal of gaseous components through venting orifices.
摘要:
The present invention relates to polyamide moldings obtainable via anionic polymerization of a lactam comprising microcapsules with a capsule core made of latent-heat-accumulator material and a polymer as capsule wall, to a process for producing the same, and also to the use of the same in motor-vehicle construction, as battery housing, as housing for small electronic devices, and for heat-retention systems for foods.
摘要:
The process for preparing a polyamide based on dicarboxylic acids and diamines has the following stages: 1) providing an aqueous monomer mixture of dicarboxylic acids and diamines, the molar ratio of dicarboxylic acids to diamines being adjusted such that a molar deficiency of dicarboxylic acids or diamines of from 1 to 10 mol % is present at the outlet of stage 3), based on the other component in each case, 2) transferring the aqueous mixture from stage 1) to a continuous evaporator reactor in which diamines and dicarboxylic acids are reacted at a temperature in the range from 100 to 370° C. and a pressure in the range from 1 to 50 bar, 3) transferring the mixture from stage 2) to a separator which is operated at a temperature in the range from 100 to 370° C. with removal of gaseous components, 4) transferring the mixture from stage 3) together with diamine or dicarboxylic acid in an amount suitable to balance out the molar deficiency into an extruder which is operated at a temperature in the range from 150 to 400° C. for a residence time in the range from 10 seconds to 30 minutes to remove gaseous components through devolatilizing orifices.
摘要:
The present invention relates to solid particles which comprise at least one lactam, and also at least one activator, and at least one catalyst, to a process for the production of these, and also to the use of these for the production of polyamide, and to a process for the production of polyamide.
摘要:
The present invention relates to a process for preparing a composition comprising (A) at least one lactam, (B) at least one catalyst, (C) an activator from the group consisting of isocyanates, acid anhydrides, acyl halides, reaction products thereof with (A) and mixtures thereof, (D) at least one polyethyleneimine. The invention likewise relates to a composition comprising (i) 0.01 to 10 wt %, based on the sum total of components (A) and (D), of at least one polyethyleneimine, and (ii) 90 to 99.99 wt %, based on the sum total of components (A) and (D), of at least one lactam (A) and/or polyamide obtainable from (A).
摘要:
Semiaromatic, semicrystalline copolyamide molding compositions, comprisingA) from 35 to 100% by weight of a copolyamide composed of a1) from 35 to 69% by weight of units which derive from hexamethylenediamine and from an aromatic dicarboxylic acid having from 8 to 16 carbon atoms, a2) from 31 to 65% by weight of units which derive from 3,3′-dimethyl-4,4′-diaminodicyclohexylmethane and from terephthalic acid, a3) from 0 to 30% by weight of units of a semicrystalline polyamide different from a1) and a2), B) from 0 to 65% by weight of further additives, where the total of the percentages by weight of A) and B) is 100%.
摘要:
A lactam composition which comprises the following components: from 3 to 25% by weight of a random vinylaromatic-diene copolymer (A), where the random vinylaromatic-diene copolymer is composed of at least one block (S) which forms a hard phase and which is composed of vinylaromatic monomers, and of at least one random block (S/B) which forms a soft phase and which has vinylaromatic monomers and diene monomers, from 75 to 97% by weight of at least one lactam component (B), and also optionally reinforcing materials and/or additives has improved viscosity in the melt and can be used for producing polyamide moldings.
摘要:
The present invention relates to binders for the preforming process to which textile structures are subjected when structural materials are produced by the RIM or RTM method, where the binder composed of an amorphous polyimide is spray applied in a solvent onto the textile structure or onto the textile, and is used as binder for the preforming process. The present invention further relates to a process for producing moldings made of fiber-reinforced composite materials.