| 摘要 |
1403461 Production of two component polymer films TH GOLDSCHMIDT AG 16 March 1973 [17 March 1972] 12832/73 Heading C3P [Also in Division B5] A heat hardenable self supporting polymer film comprises 0À05-1 wt. per cent (based on the weight of the film) of an acid catalyst for the hardening, and (A) an elastomeric copolymer of Tg up to 10‹ C., obtained by the polymerization of (a 1 ) 78-99 wt. per cent of a C 1-8 alkyl acrylate, (a 2 ) 1-2 wt. per cent of a C 2-4 hydroxyalkyl ester and/or an amide of acrylic or methacrylic acid, and (a 3 ) 0-2 wt. per cent of one or more crosslinking monomers having two or more ethylenic bonds (the total of a 1 -a 3 being 100 wt. per cent), and (B) a hard brittle polymer obtained in the presence of polymer A by polymerization of (b 1 ) 60-80 wt. per cent of styrene and/or one or more C 1-20 alkyl methacrylates (b 2 ) 0-20 wt. per cent of one or more C 1-8 alkyl acrylates, (b 3 ) 1-20 wt. per cent of an N-methoxymethyl acrylamide and/or methacrylamide, (b 4 ) 1-20 wt. per cent of a C 2-4 hydroxyalkyl acrylate or methacrylate, (b 5 ) 1-20 wt. per cent of acrylamide or methacrylamide and (b 6 ) 0-20 wt. per cent of acrylonitrile, where the sum of b 1-6 is 100 wt. per cent and the molar ratio of b 3 to b 4 plus b 5 is approximately 1 : 1 and the molar ratio of b 4 to b 5 is from 4 : 1 to 1 : 4, and wherein also the weight ratio of polymer A to polymer B is from 1 : 3 to 1 : 20. The film may also contain a plasticizer and/or pigment and/or B-stage melamine formaldehyde resin. The film is formed by polymerizing the "A" monomers, then adding the "B" monomers and polymerizing in the presence of polymer A, and forming the film. Polymerization is preferably effected in solution, and the film formed by evaporation of the solvent. |
