Kinetic Studies of the Solution Polymerization of Trioxane Catalyzed by BF3·O(C2H5)2. V. The Effect of the Solvent and of the Polymerization Temperature

Abstract

Abstract The effect of the polarity of solvents in the solution polymerization of trioxane catalyzed by BF3·O(C2H5)2 has been studied. While the molecular weight of the resulting polymer is almost independent of the kind of solvent, the rate of polymerization in a polar solvent is large at a high initial monomer concentration. At a low monomer concentration, however, the rate of polymerization in a non-polar solvent is larger than that in a polar solvent. This fact can probably be explained by observing that, at the low monomer concentration, the initiation species produced from the catalyst is solvated by the solvent molecule rather than by trioxane because of the small basicity of trioxane. The activation energies of the over-all polymerization rate as determined in ethylene dichloride, nitroethane and nitrobenzene are all about 16 kcal./mol. The decrease in the molecular weight of the resulting polymers caused by raising the temperature is very small.