摘要：

Three starch-polyacrylonitrile (S-PAN) graft copolymers containing ratios of S:PAN of 1:1.90, 1:1.16, and 1:0.64 were prepared by graft polymerization of acrylonitrile onto gelatinized starch. A fourth graft, made from granular starch, had an S:PAN ratio of 1:2.16. These grafts were hydrolyzed in potassium hydroxide under various conditions to give a series of products with varying amounts of carboxylic acid and amide groups. Maximum conversion of nitrile to carboxyl was 65%. Aqueous dispersions of the hydrolyzed S-PAN's at pH 7-8.5 were viscous, and, in general, their viscosities reflected the amount of PAN add-on, with the highest add-on giving the highest viscosity. Plots of the / C versus C show that hydrolyzed S-PAN's from gelatinized starch behave as normal polyelectrolytes on dilution to low concentration but that S-PAN from granular starch does not.

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