| 摘要 |
1,137,624. Grafting monomers on to regenerated cellulose. SCOTT PAPER CO. 4 Feb., 1966 [15 Feb., 1965], No. 5098/66. Heading C3G. A copolymer of an ethylenically unsaturated compound and cellulose is prepared by a pro- cess comprising (1) regenerating viscose dope in an acidic regenerating bath to form a regenerated cellulose which has been sufficiently regenerated to enable it to remain insoluble during the subsequent washing and polymerization steps, yet which contains a sufficient number of residual thiocarbonate groups to complete with a peroxidic initiator a redox couple which is strong enough to initiate the subsequent copolymerization of the regenerated cellulose with an ethylenically unsaturated monomer, (2) washing the regenerated cellulose with an ethylenically unsaturated monomer, and (3) reacting the freshly regenerated, thiocarbonate-containing cellulose with at least one polymerizable ethylenically unsaturated monomer in the presence of a peroxidic initiator. The washed regenerated cellulose from stage (2) may be reacted by metathesis with a watersoluble salt prior to being reacted in stage (3). The cellulose copolymer produced is subjected to conventional rayon post-spinning treatments, e.g. desulphuring. In Examples 1 to 5, a viscous dope solution is regenerated by treatment firstly in an aqueous H 2 SO 4 /Na 2 SO 4 / glucose/ZnSO 4 bath and secondly in an aqueous Na 2 CO 3 bath and washed, the resulting filaments being suspended in an aqueous emulsion containing H 2 O 2 and copolymerized therein with (i) styrene and acrylonitrile, (ii) acrylic acid, (iii) ethyl acrylate, (iv) acrylamide, or (v) acrylonitrile. The viscose dope solution in Example 6 is regenerated in an aqueous H 2 SO 4 /Na 2 SO 4 bath and treated with Ca(NO 3 ) 2 solution and the regenerated product obtained is copolymerized with ethyl acrylate by the process of the previous examples. Similarly, in Examples 7 to 16, ferrous, lead, aluminium, magnesium or zinc thiocarbonate salts of regenerated cellulose are prepared and copolymerized with acrylonitrile or methyl acrylate. The regenerated cellulose copolymers produced may be mixed with, e.g. rubber, polystyrene, polyethylene or polyvinyl chloride. |
