Bulk Polymerization of Vinyl Acetate with Tri-n-Butyl Boron as an Initiator

Abstract

Bulk polymerization of vinyl acetate initiated with tri-n-butyl boron was studied kinetically at 10°C.
The rate of polymerization was found to be expressed by an equation R p=const.[I]. The chain transfer constant of tri -n- butyl boron was 0.9. The apparent activation energy for the polymerization was calculated to be 6.0-6.5 kcal/mol.
A number of polymerizations were carried out in the temperature range from -30°C to + 30°C. The average degrees of polymerization of polyvinyl acetate increased at first with increaing polymerization temperature and then decreased, passing through a maximum at about 30°C.