In 1962 Kimura, Takitani, and Imoto [1] found that an aqueous solution of starch could easily polymerize methyl methacrylate (MMA), and about one-half of the polymerized MMA was grafted on to starch. This novel polymerization was called “uncatalyzed polymerization.” Since then, a large number of macromolecules other than starch have been studied, and many of them are effective for initiating the radical polymerization of MMA.