A Kinetic Study of the Radical Polymerization of Polytetrahydrofuran Macromer

Abstract

The kinetics of the radical polymerization of P-vinylbenzyloxy- and P-vinylphenoxy-polytetrahydrofuran macromers were studied in dilute solutions at 60°C by a spectrophotometric method. In the case of an extremely low macromer concentration ([C=C]<1.6×10−3 mol dm−3), the rate of polymerization was independent of macromer concentration but proportional to the square root of initiator concentration. In addition, the degree of polymerization of recovered polymer was shown by GPC to be about unity in spite of the consumption of nearly all the vinyl groups of the macromer molecules. When the macromer concentration was above 1.6×10−3 mol dm−3, however, the kinetics of the radical polymerization were in accord with those of conventional vinyl monomers. These results are discussed in terms of the low concentration of vinyl groups of the macromer molecules.