摘要:
Thermoplastic molding compositions comprising A) from 10 to 99.94% by weight of a polyamide, B) from 0.05 to 5% by weight of a polyethyleneimine homo- or copolymer, C) from 0.01 to 20% by weight of iron powder, and D) from 0 to 70% by weight of further additives, where the total of the percentages by weight of A) to D) is 100%.
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, comprising A) 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:
The invention relates to a process for preparing polymers from monomers and/or oligomers by adding a liquid comprising the monomers and/or oligomers dropwise to a continuous liquid phase in a reactor, the continuous liquid phase being immiscible with the liquid comprising the monomers and/or oligomers, and the monomers and/or oligomers reacting in the continuous liquid phase to give the polymer. The liquid comprising the monomers and/or oligomers is shaped to droplets outside the continuous liquid phase, which are subsequently introduced into the continuous liquid phase. The invention further relates to a reactor for performing the process, comprising a tube through which a continuous liquid phase flows, and means of generating droplets, the means of generating droplets being arranged such that the droplets are generated outside the continuous liquid phase and then introduced into the continuous liquid phase.
摘要:
The use of thermoplastic molding materials comprising A) 10 to 98.8% by weight of a mixture formed from a1) 40 to 70% by weight of nylon-6,6 or nylon-4,6 or nylon-6 or mixtures thereof, a2) 30 to 60% by weight of a polyamide having a ratio of methylene to amide groups of 7 to 12, B) 1 to 50% by weight of a fibrous or particulate filler, C) 0.1 to 3% by weight of a lubricant, D) 0.05 to 3% by weight of a heat stabilizer, E) 0 to 40% by weight of further additives, where the sum of the percentages by weight A) to E) and a1) and a2) adds to 100%, for production of stress cracking- and corrosion-resistant moldings.
摘要:
Thermoplastic molding compositions, comprising A) from 10 to 99.999% by weight of a polyimide B) from 0.001 to 20% by weight of iron powder with a particle size of at most 10 μm (d50 value), which is obtainable via thermal decomposition of pentacarbonyliron, C) from 0 to 70% by weight of further additives, where the total of the percentages by weight of components A) to C) is 100%.
摘要:
The invention relates to a process for producing moldings made of a fiber-reinforced polymer, comprising the following steps:(a) inserting a fiber structure into a mold and injecting a polymer precursor compound around the fiber structure or saturating a fiber structure with a polymer precursor compound and inserting the saturated fiber structure into a mold, where the viscosity of the polymer precursor compound is at most 2000 mPas,(b) polymerizing the polymer precursor compound to give the polymer, to produce the molding,(c) removing the molding from the mold as soon as the polymerization process has proceeded at least to the extent that the molding is in essence dimensionally stable.
摘要:
Thermoplastic molding compositions comprising A) from 10 to 99.94% by weight of a polyamide, B) from 0.05 to 5% by weight of a polyethyleneimine homo- or copolymer, C) from 0.01 to 20% by weight of iron powder, and D) from 0 to 70% by weight of further additives, where the total of the percentages by weight of A) to D) is 100%.
摘要:
Thermoplastic molding compositions, comprising A) from 10 to 99% by weight of at least one thermoplastic polyamide, B) from 0.01 to 50% by weight of B1) at least one highly branched or hyperbranched polycarbonate with an OH number of from 1 to 600 mg KOH/g of polycarbonate (to DIN 53240, Part 2), or B2) at least one highly branched or hyperbranched polyester of AxBy type, where x is at least 1.1 and y is at least 2.1, or a mixture of these, C) from 0 to 60% by weight of other additives, where the total of the percentages by weight of components A) to C) is 100%.
摘要:
Polyamides based on dicarboxylic acids and on diamines are produced in a batch process by 1) feeding the entire amount of monomer composed of dicarboxylic acids, of diamines, and, if appropriate, of further polyamide-forming monomers, in the desired stoichiometry, in a closed stirred-tank reactor, 2) heating the monomer mixture in the stirred-tank reactor, with stirring, and with setting of a certain pressure, to a desired reaction temperature for the production of a prepolymer, 3) if appropriate, completely or partially depressurizing the reaction mixture from stage 2), 4) if appropriate, carrying out further thermal treatment of the reaction mixture from stage 2) or 3), and 5) reacting the reaction mixture from stage 2), 3), or 4) in the melt in a vented extruder for further increase of the molecular weight, with discharge of water vapor, and without use of additional polyamide-forming monomers or of polyamides.