摘要:
Thermoplastic molding compositions comprising A) from 10 to 98.9% by weight of at least one thermoplastic polyester, B) from 0.01 to 50% by weight of B1) at least one highly branched or hyperbranched polycarbonate having 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 the AxBy type where x is at least 1.1 and y is at least 2.1 or mixtures thereof C) from 0.1 to 10% by weight of at least one carbodiimide, D) from 0 to 60% by weight of further additives, the sum of the percentages by weight of components A) to D) adding up to 100%.
摘要:
Thermoplastic molding compositions, comprising A) from 10 to 98.9% by weight of at least one thermoplastic polyester, B) from 0.01 to 50% by weight of B1) at least one highly branched or hyperbranched polycarbonate 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 0.1 to 10% by weight of at least one epoxidized naturally occurring oil or fatty acid ester, or a mixture of these, and D) from 0 to 60% by weight of other additives, where the total of the percentages by weight of components A) to D) is 100%.
摘要:
Use of epoxidized natural oils or fatty esters, or a mixture of these (component B) for preparing hydrolysis-resistant thermoplastic polyester molding compositions (A).
摘要:
Mixtures of diphenylmethane diisocyanates and polyphenylpolymethylene polyisocyanates (raw MDI) having a reduced iodine color number and a reduced chlorine content are prepared by reacting the corresponding mixtures of diphenylmethanediamines and polyphenylpolymethylenepolyamines with phosgene in the presence of at least one inert organic solvent at elevated temperature, and then, after phosgenation is complete, incorporating into the reaction mixture, in the presence or absence of the phosgene, a mixture of water and at least one monohydric or polyhydric polyoxyalkylene alcohol, preferably having a functionality of from 2 to 3, and advantageously having a hydroxyl number of from 20 to 1800, in an effective amount which advantageously comprises from more than 0.01 to 0.3% by weight of water (i) and from 0.5 to 5% by weight of a polyoxyalkylene alcohol (ii), in each case based on the weight of raw MDI, then removing the excess phosgene or the phosgene residues still present and the inert organic solvent, if desired adding to the reaction product up to 5% by weight, based on the weight of raw MDI, of at least one antioxidant based on phenol and/or aryl phosphite and thermally treating the reaction mixture.
摘要:
A process for the preparation of foamed plastics materials based on polyisocyanate polyaddition products by the reaction of isocyanates with isocyanate-reactive compounds in the presence of catalysts and, optionally, auxiliaries and/or additives, wherein i) isocyanates having isocyanurate and/or biuret structures are used, the isocyanate-reactive compounds used are ii) at least one diol and/or polyol having a molecular weight of from 400 to 8000 and containing at least 50% of primary hydroxyl groups based on all of the hydroxyl groups present in the compound, iii) at least one compound having at least one primary amine group, and diols and/or triols having molecular weights of less than 400 are optionally used as chain-extending and/or crosslinking agents, the reaction being carried out in the presence of iv) at least one tertiary amine acting as catalyst and/or v) at least one metal salt acting as catalyst and vi) water.
摘要:
In a process for producing sheet-like polyurethane moldings by impregnation of porous sheets with a polyurethane system and subsequent reaction of the polyurethane system in a mold, the porous sheet is first fully impregnated with a polyurethane component, then fully impregnated with the other polyurethane component and the molding is then produced in a heated mold by reaction of the polyurethane components.
摘要:
The invention relates to a process for the preparation of CFC-free, flexible polyurethane foams or molded foams by reactingA) liquid polyisocyanate mixtures containing bonded urethane groups and having a content of NCO groups of from 20 to 30% by weight, these mixtures themselves being prepared by reacting a mixture of diphenylmethane diisocyanates and polyphenyl-polymethylene polyisocyanates (crude diphenylmethane diisocyanate) with a polyether-polyol mixture, having a hydroxyl number of from 120 to 25, of at least one polyoxypropylene glycol and at least one trifunctional polyoxypropylene-polyoxyethylene glycol having a content of ethylene oxide units of from 90 to 10% by weight or by reacting 4,4'-diphenylmethane diisocyanate (diphenylmethyl diisocyanate) or an diphenylmethane diisocyanate isomer mixture with said polyether-polyol mixture to give an NCO-containing quasi-prepolymer and diluting this quasi-prepolymer with crude diphenylmethane diisocyanate, withB) relatively high-molecular-weight polyhydroxyl compounds.
摘要:
The invention relates to a process for the preparation of CFC-free, flexible polyurethane foams or molded foams by reactingA) liquid polyisocyanate mixtures containing bonded urethane groups and having a content of NCO groups of from 20 to 30% by weight, these mixtures themselves being prepared by reacting a mixture of diphenylmethane diisocyanates and polyphenyl-polymethylene polyisocyanates (crude diphenylmethane diisocyanate) with a polyether-polyol mixture, having a hydroxyl number of from 120 to 25, of at least one polyoxypropylene glycol and at least one trifunctional polyoxypropylene-polyoxyethylene glycol having a content of ethylene oxide units of from 90 to 10% by weight or by reacting 4,4'-diphenylmethane diisocyanate (diphenylmethyl diisocyanate) or an diphenylmethane diisocyanate isomer mixture with said polyether-polyol mixture to give an NCO-containing quasi-prepolymer and diluting this quasi-prepolymer with crude diphenylmethane diisocyanate, withB) relatively high-molecular-weight polyhydroxyl compounds.