Graft copolymers
Реферат: 1428500 Graft polymer particles and compositions containing them ROHM GmbH 27 Dec 1973 [30 Dec 1972] 59818/73 Headings C3G and C3P A particulate graft polymer comprises a core of a cross-linked emulsion copolymer containing a major proportion of units of a styrene monomer, the said core having a particle size greater than 0À8 micron and being provided with a coating of a polymer containing a major proportion of units of methyl methacrylate grafted on to the said emulsion copolymer. The crosslinked units may be of glycol di-methacrylate or di-acrylate, allyl acrylate or methacrylate, divinyl benzene or triallyl cyanurate and the emulsion copolymer may also contain units of, e.g. vinyl toluene, N-vinylcarbazole, benzyl acrylate or benzyl methacrylate. The coating may comprise units of an acrylic or methacrylic acid ester containing 1 to 6 carbon atoms in the alcohol moiety, acrylonitrile, vinyl acetate or styrene. Moulding compositions may comprise a polymer containing a major proportion of methacrylate monomer units together with the graft copolymer in an amount of, e.g. 0À1 to 1% by weight. Examples are given in which (a) styrene-glycol dimethacrylate copolymer particles prepared by a 2-stage emulsion process are grafted with methyl methacrylate, or a mixture thereof with styrene; (b) styrenebenzyl methacrylate-butanediol diacrylate copolymer produced by a process as in (a) are grafted with methyl methacrylate; (c) styrene/ N-methoxymethyl methacrylamide copolymer is produced and grafted as in (a). Graft polymer produced as in (a) is (i) mixed with polymethyl methacrylate directly, or (ii) is suspended in methyl methacrylate and the resulting paste is mixed in an extruder with polymethyl methacrylate melt, or (iii) is disposed in methyl methacrylate containing polymethyl methacrylate and the resulting mixture polymerized in the presence of azodiisobutyrodinitrile.
Elastomeric graft copolymers having a core/shell structure
Номер патента: US5223586A. Автор: Bernward Deubzer,Konrad Mautner. Владелец: Wacker Chemie AG. Дата публикации: 1993-06-29.