Patent ID: 8680201
Filing Date: 2014-03-25
Classification: B29B,B29C,C08J,C08L

Abstract:
1. A method for producing an impact-modified polymer composition comprising: A) at least one rubber-free organic thermoplastic polymer, B) at least one pulverulent graft polymer consisting of C) optionally a further polymer resin that is at least one polymer selected from the group consisting of a rubber-free vinyl (co)polymer C.1 and a pellet-form rubber-modified vinyl (co)polymer C.2, D) optionally at least one polymer additive different from components A, B and C, wherein said polymer additive is selected from the group consisting of flame retardants, flameproofing synergists, smoke-retarding additives, antidripping agents, internal and external lubricants and mould release agents, rheological auxiliaries, antistatic agents, conductivity additives, stabilisers, antibacterially active additives, scratch resistance-improving additives, IR absorbents, optical brighteners, fluorescent additives, fillers and reinforcing materials, dyes, pigments, Brønsted acid compounds, and mixtures thereof, wherein the total of the VOC contents of initial raw materials, weighted in each case with the respective percentages of components A to C in the composition, is more than 600 ppm and UP to 2000 ppm, said method comprising: (i) producing a mixture with a water content, relative to the mixture produced in step (i), of 2 to 40 wt. % from (ii) heating the mixture resulting from step (i) together with the respective total quantities or the proportions of components A to D of the composition remaining after step (i) in a compounding unit by input of thermal and/or mechanical energy to a temperature of 200° C. to 350° C., and thereby melting, mixing and/or dispersing the different components A to D in one another and subsequently devolatilising the melt of the resulting mixture in a devolatilising zone of the compounding unit to form a devolitised premixed melt, (iii) resolidifying the melt resulting from step (ii) by cooling on discharge from the compounding unit wherein the impact-modified polymer composition has a volatile organic compounds (VOC) content of no more than 600 ppm.