GRAFT CO-POLYMERIZATION OF METHYL METHAERYLATE ONTO DEXTRAN AND SOME PROPERTIES OF COPOLYMER - STUDY OF DEXTRAN COPOLYMER .2.

Graft copolymers consisting of dextran and methyl methacrylate were prepared by using various concentrations of ceric ammonium nitrate, monomer, and backbone polymer. Spectrophotometric studies on dextran-Ce4+solution have revealed the existence of an intermediate complex similar to Ce4+-alcohol of low molecular weight. The grafting(%) increased with the increase in the initiator concentration to reach a maximum in the vicinity of the initiator concentration about 1.3 mmol for dextran of Mw61,000. The weight of copolymer increased but the total conversion decreased with increase in monomer concentration. For the dextran of Mw196,000, the grafting(%), the grafting efficiency, and the graft polymerization (%) were minima at dextran concentrations of about 5.5, 5.5, and 3~4%, respectively, whereas the total conversion remained constant(ca. 75%). The graft copolymers are insoluble in water and conventional organic solvents and their thermal and mechanical properties are different from PMMA. The copolymer can be hot-pressed into plates, which have hydrophilic-hydrophobic microphase-separated structure and better water wettability and biocompatibility than the plate made from PMMA. © 1979, The Society of Polymer Science, Japan. All rights reserved.