摘要:
A process is proposed for coagulation of an aqueous polymer dispersion, which comprises, during or after the coagulation, converting the dissolved coagulation salt into an insoluble form.
摘要:
Halogen-free antidrip agents for thermoplastic molding materials contain polymers based on vinylaromatic monomers and having molecular weights (M.sub.w) of at least 800 000 g/mol and a narrow molecular weight distribution.
摘要:
Molding materials modified with acrylic rubber are prepared by means of groups which are incorporated in the acrylic rubber and are decomposed by a redox component to give free radicals.
摘要:
Particulate elastomeric graft polymers which are suitable for improving the quality of macromolecular base materials B consist ofa) a grafting core comprising an elastomeric polymer P.sub.K, the particles having a mean particle diameter of from 1 to 150 .mu.m, andb) one or more shells, the outer shell S.sub.a consisting of a polymer P.sub.a which is compatible or partly compatible with the base material B.
摘要:
Particulate graft copolymers A) are composed of a.sub.1) from 5 to 70% by weight, based on A), of a grafting base having a glass transition temperature of less than 10.degree. C. and based on a.sub.11) from 50 to 99.94% by weight, based on a.sub.1), of at least one alkyl acrylate where the alkyl radical is of 1 to 30 carbon atoms, a.sub.12) from 0 to 49.9% by weight, based on a.sub.1), of a further monounsaturated monomer copolymerizable with b.sub.11) and a.sub.13) from 0.01 to 5% by weight, based on a.sub.1), of polyfunctional crosslinking monomers, a.sub.2) from 20 to 85% by weight, based on A), of a stage polymerized in the presence of component a.sub.1) and comprising a.sub.21) from 95 to 100% by weight, based on a.sub.2), of at least one monomer having a refractive index n.sub.D.sup.20 of more than 1.51 and a.sub.22) from 0 to 5% by weight, based on a.sub.2), of a polyfunctional, crosslinking monomer and a.sub.3) from 10 to 50% by weight, based on A), of at least one further stage polymerized in the presence of the product obtained after the preparation of a.sub.2) and comprising a.sub.31) from 50 to 95% by weight, based on a.sub.3), of a vinylaromatic monomer and a.sub.32) from 5 to 50% by weight, based on a.sub.3), of polar, copolymerizable comonomers selected from the group consisting of acrylonitrile, methacrylonitrile, esters of (meth)acrylic acid where the alkyl radical is of 1 to 20 carbon atoms, maleic anhydride, (meth)acrylamide and/or vinyl alkyl ethers where the alkyl radical is of 1 to 8 carbon atoms.
摘要:
Mixture (1) comprising from 1 to 40% by weight of (A) thermoplastic polyurethane based on aliphatic isocyanate and from 60 to 99% by weight of (B) acrylonitrile-styrene-acrylate copolymer (ASA) and/or acrylonitrile-ethylene homo- or copolymer-styrene (AES) material, based in each case on the total weight of the mixture (1).
摘要:
A particulate polymer P having an average particle diameter d50 of from 0.1 to 50 &mgr;m is prepared by a process in which an emulsion E is prepared from one or more monomers M, which are polymerizable by free radical polymerization to give the polymer P, water, and at least one protective colloid PC by the action of high shear forces, and the emulsion E is subjected to polymerization in a reactor with the use of a free radical polymerization initiator RI wherein, based on the emulsion E, not more than 75% by weight of the emulsion E (initially taken portion of E) are initially taken in the reactor at the beginning of the polymerization and at least 25% by weight of the emulsion E (feed portion of E) are not fed to the reactor until after the beginning of the polymerization.
摘要:
Rubber-modified molding materials having improved impact strength in combination with good flow behavior can be prepared by special graft polymerization of monomers forming hard graft shells, such as styrene and acrylonitrile, in the presence of an elastomeric acrylate macromonomer copolymer dissolved or swollen in these monomers, the graft polymerization being carried out, to a conversion of more than 15% by weight of the monomers, by thermal or free radical mass or solution polymerization.
摘要:
In the preparation of a rubber-modified molding material, in a first stage, a first mixture (A) contains at least one alkyl acrylate or methacrylate (a) of the formula (I) ##STR1## where R.sup.1 is hydrogen or methyl and R.sup.2 is alkyl of 1 to 32 carbon atoms, at least one first monomer (b) which forms free radicals on thermal decomposition and, if required, a second monomer (c) or a plurality thereof is polymerized, preferably with free radicals, to give a rubber (B),in a second stage, the resulting rubber (B) is mixed with a third monomer (d) or a plurality thereof, preferably dissolved or swollen therein, to form a second mixture (C), andin a third stage, the second mixture (C) is polymerized with free radicals to give the rubber-modified molding material (D).
摘要:
In the preparation of a rubber-modified molding material, in a first stage, a first mixture (A) contains at least one alkyl acrylate or methacrylate (a) of the formula (I) ##STR1## where R.sup.1 is hydrogen or methyl and R.sup.2 is alkyl of 1 to 32 carbon atoms, if required a first monomer (b) having two or more double bonds and, if required, also a second monomer (c) or a plurality thereof is polymerized, preferably with free radicals, to give a rubber (B), in a second stage, a third monomer (d) or a plurality thereof is added to the resulting rubber (B) to form a second mixture (C), whereby the rubber (B) is dissolved or swollen in the third monomer (d), with or with the addition of a solvent, and in a third stage, the second mixture (C) formed is polymerized with free radicals to give the rubber-modified molding material (D), and the mixture is reacted at >120.degree. C., during or after this polymerization, with a compound (e) which contains at least two peroxy groups.