| 摘要 |
PURPOSE:To obtain a copolymer with excellent compatibility with thermoplastic polymer useful for biodegradable plastic or the like by a method wherein starch is converted to meleic acid half ester and thereafter is graft-polymerized with styrene monomer by using a convertional polymerization catalyst. CONSTITUTION:To starch as a main polymer, one or more monomers selected from styrene and derivative thereof alone or along with one or more other polymerizable monomers are graft-polymerized together. In this case, after starch is converted to maleic acid ester, above-described monomer components are graft-polymerized to obtain a graft copolymer having starch as a main polymer. Herein, the substitution degree of malein acid half ester is 0.01-3.00. As a polymerization catalyst, a convertional catalyst such as benzoyl peroxide, azobisbutyronitrile, potassium persulfate or the like are used and grafting ratio as well as graft efficiency can be improved. |
