Impact-modified polycarbonate compositions having a good combination of natural color, hydrolytic stability and melt stability

摘要

The present invention relates to polycarbonate compositions comprising
A) from 10 to 99 parts by weight, in each case based on the sum of components A+B+C, of aromatic polycarbonate and/or aromatic polyester carbonate,B) from 1 to 35 parts by weight, in each case based on the sum of components A+B+C, of rubber-modified graft polymer of
B.1 from 5 to 95 wt. % of at least one vinyl monomer onB.2 from 95 to 5 wt. % of one or more graft bases having a glass transition temperature <10° C.,C) from 0 to 40 parts by weight, in each case based on the sum of components A+B+C, of vinyl (co)polymer and/or polyalkylene terephthalate,D) from 0 to 50 parts by weight, in each case based on the sum of components A+B+C, of phosphorus-containing flameproofing agent,E) from 0 to 1.0 part by weight, in each case based on the sum of components A+B+C, of acidic additives, andF) from 0 to 50 parts by weight, in each case based on the sum of components A+B+C, of additives,wherein component B is obtainable by reacting component B.1 with the graft base B.2 by means of emulsion polymerization, with the proviso that in those compositions that are free of components D) and E), the graft polymer dispersion in the spray drying or in the precipitation has a pH value of less than 7,characterized in that there are used in the graft reaction from 0.1 to 5 parts by weight (based on the sum of the parts by weight of the monomers B.1 and of the graft base B.2 that are used=100 parts by weight) of at least one emulsifier selected from the group consisting of alkali, alkaline earth, ammonium and phosphonium salts of a saturated fatty acid having from 10 to 50 carbon atoms, wherein the emulsifier or emulsifiers remains or remain in component B,

and also to a process for the preparation of these polycarbonate compositions and to the use of the polycarbonate compositions in the production of molded bodies, and to the molded bodies themselves.

主权项

1. A composition comprising
A) from 10 to 99 parts by weight, in each case based on the entirety of components A+B+C, of aromatic polycarbonate and/or aromatic polyester carbonate, B) from 1 to 35 parts by weight, in each case based on the entirety of components A+B+C, of rubber-modified graft polymer of
B.1 from 5 to 95 wt. % of at least one vinyl monomer onB.2 from 95 to 5 wt. % of one or more graft bases having a glass transition temperature <10° C.,wherein the rubber-modified graft polymer component B) comprises 0.1 to 5 parts by weight of an emulsifier comprising potassium stearate (C17H35COOK), or sodium stearate (C17H35COONa), or a combination thereof, based on the total weight of the at least one vinyl monomer B.1 and the graft base B.2, C) from 0 to 40 parts by weight, in each case based on the entirety of components A+B+C, of resinous, thermoplastic and rubber-free vinyl (co)polymer and/or polyalkylene terephthalate, D) from 0 to 50 parts by weight, in each case based on the entirety of components A+B+C, of phosphorus-containing flame retardant, E) from 0 to 1.0 part by weight, in each case based on the entirety of components A+B+C, of acidic additives and F) from 0 to 50 parts by weight, in each case based on the entirety of components A+B+C, of additional substances, wherein component B is obtained by reacting component B.1 with the graft base B.2 by emulsion polymerisation, with the proviso that, in the case of compositions that are free of components D) and E), the pH of the graft polymer dispersion during a precipitation step is less than 7, and the graft polymer is precipitated from the dispersion by addition of magnesium sulphate, where the emulsifier or emulsifiers and magnesium sulphate remain in component B.