| 摘要 |
Stable aqueous dispersions of ternary copolymers are obtained by emulsifying (a) 1 to 4 parts by weight of acrolein, (b) 10 to 20 parts by weight of acrylonitrile and (c) 79 to 86 parts by weight of ethyl acrylate-the sum of (a+b+c) always being 100 parts by weight-in an aqueous medium in the presence of an emulsifier and copolymerizing the resulting emulsion using as Redox catalyst hydrogen peroxide and ascorbic acid. Ferrous ions in the form of Mohr's salt may be used as actiator. Conventional anionic and cationic emulsifiers may be used. The copolymers may be cross-linked e.g. with hydrazine hydrate.ALSO:Stable aqueous dispersions of copolymers of acrolein, acrylonitrile and ethyl acrylate (see Division C3) are used for dressing leather and coating paper and textile materials. The Examples describe the use of compositions comprising a commercial casein-free topping dye or pigment paste, water and the copolymer dispersion. Chrome-side or clothing leather is whetted, after-tanned, pre-dyed, plush-wheeled with the above composition, dried, ironed, sprayed cross-wise with the composition, dried and ironed again. |
