Abstract:
The present invention relates to a process for the production of styrene graft copolymers comprising addition and graft copolymerization of styrene monomers A1 and vinyl cyanide monomers A2 to a graft base B where the ratio by mass of A1 to A2 in the monomer feed at the end of the monomer feed time is lower than the ration by mass integrated over the entire monomer feed time. The present invention further relates to a graft copolymer obtainable by a process according to the invention, a molding composition comprising such a graft copolymer, and a molding obtained from such a molding composition.
Abstract:
The invention relates to a process for the production of thermoplastic moulding compounds, in particular for the production of acrylonitrile-butadiene-styrene (ABS), wherein at least a first reagent (11) and a second reagent (12) of the thermoplastic moulding compounds are fed to a loop conduit (29) which comprises a static mixer (36), wherein the reagents (11, 12) are pressed in loops through the loop conduit (29) and passing the static mixer (36), whereby the reagents (11, 12) are dispersed to form a dispersion (15) in the static mixer (36). The invention also relates to a thermoplastic moulding compound that is produced by the inventive process.
Abstract:
The invention relates to a process for the production of thermoplastic moulding compounds, in particular ABS, wherein at least a first reagent (11) and a second reagent (12) of the thermoplastic moulding compounds are fed to a gear pump (10) which comprises a housing and at least a first gear wheel that is rotatable relative to the housing about a first axis, and a second gear wheel that is rotatable relative to the housing about a second axis, wherein a loop conduit (29) is provided, and wherein the reagents (11, 12) are pressed in a loop through the loop conduit (29) and passing the gear wheels, whereby the reagents (11, 12) are dispersed to form a dispersion (15) in the gear pump (10). The invention also relates to a thermoplastic moulding compound that is produced by the inventive process.
Abstract:
A process produces a polymer composition (A) containing a styrene copolymer (a) and an impact modifier (b), comprising a copolymer (b1) as graft base and a graft (b2), where the steps of the process are: (1) providing a crosslinked copolymer (b1) made of: (b11) from 70 to 99.99% by weight of a conjugated diene or acrylate, (b12) from 0 to 29% by weight of another comonomer, (b13) from 0 to 10% by weight of crosslinking monomers, and (b14) from 0.01 to 0.7% by weight of a chain-transfer reagent; (2) applying, to the copolymer (b1), at least one graft (b2) comprising: (b21) from 65 to 95% by weight of a vinylaromatic monomer, (b22) from 5 to 35% by weight of acrylonitrile and/or methacrylonitrile, and (b23) from 0 to 30% by weight of monoethylenically unsaturated monomers, thus providing the impact modifier (b); (3) mixing the styrene copolymer (a) and the impact modifier (b), and thus leads to improved mechanical properties of the polymer composition (A).
Abstract:
The invention relates to graft copolymers (B) composed of an agglomerated graft core (B1) and at least one graft shell (B2) and also to copolymers (C) having an agglomerating effect, a method for producing said graft copolymers (B), thermoplastic molding compositions and also the use of the thermoplastic molding compositions.
Abstract:
A process for preparing an ABS graft copolymer, which comprises a step for isolating the graft copolymer B present in an aqueous dispersion by means of a precipitant which is an aqueous solution of a mixture of MgSO4, Al2(SO4) and/or H2SO4, is described. The ABS molding compositions obtained have an improved yellowness index and high surface gloss.
Abstract:
The invention relates to a thermoplastic composition containing the components A and B and optionally the additional components C and D, the sum of which equals 100 wt. %. The molding compound consists of: a) 60 to 75 wt. % of one or more styrene copolymers A, b) 25 to 40 wt. % of one or more graft copolymers B, c) 0 to 15 wt. % of a rubber C which is different from component B, and d) 0 to 5 wt.% of one or more additives D. The composition contains 0.2 to 3.0 wt. %, based on the total weight of the components A to D, of oligomers, can be readily processed, and leads to scratch-resistant molded parts.
Abstract:
The invention relates to thermoplastic ABS molding compositions comprising components A) and B): A) from 5 to 80% by weight of a graft polymer A) having bimodal particle size distribution made from, based on A), a1) from 40 to 90% by weight of graft base a1), obtainable by polymerization of, based on a1), a11) from 75.5 to 89.5% by weight of at least one conjugated diene, a12) from 10.5 to 24.5% by weight of at least one vinylaromatic monomer and a2) from 10 to 60% by weight of a graft a2) made from, based on a2), a21) from 65 to 95% by weight of at least one vinylaromatic monomer, a22) from 5 to 35% by weight of acrylonitrile, and a23) from 0 to 30% by weight of at least one other monoethylenically unsaturated monomer, B) from 20 to 95% by weight of a thermoplastic polymer B) having a viscosity number VN of from 50 to 120 ml/g, made from, based on B), b1) from 69 to 81% by weight of at least one vinylaromatic monomer, b2) from 19 to 31% by weight of acrylonitrile, and b3) from 0 to 30% by weight of at least one other monoethylenically unsaturated monomer. The invention further relates to a process for the preparation of graft copolymer A and to the graft copolymer obtainable by said process.