| 摘要 |
Novel cationic starch-g-poly(N,N'-methylenebisacrylamide-co-amine) copolymers, useful as pigment retention aids for paper, are prepared by reacting a starch base with N,N'-methylenebisacrylamide and a polyamine or with preformed copolymer. The reactions are carried out at 15 DEG to 80 DEG C. for 0.5 to 20 hours under alkaline conditions using an aqueous slurry or dispersion of a starch base and preferably a salt such as sodium sulfate. The starch base may be derivatized, prior to the graft copolymerization, to introduce ether groups. The polyamines contain at least two amine groups selected from primary and secondary amines; preferably they contain up to 4 amine nitrogens, some of which may be unreactive tertiary amine nitrogens.
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