S. Mehta et al., PRACTICAL ASPECTS OF POLYMERIZATION OF D,L-LACTIDE INITIATED WITH TETRAPHENYLTIN, Journal of applied polymer science, 58(9), 1995, pp. 1495-1499
Melt polymerization conditions for D,L-Lactide initiated with tetraphe
nyltin were studied with regard to polymer molecular weight. The combi
ned effect of time and temperature on polymer molecular weight and deg
ree of conversion of D,L-Lactide is described. Polymerization at const
ant initiator concentrations resulted in a narrow scattering of reprod
ucible molecular weight values. The presence of air/moisture and other
impurities during the melt polymerization most likely have a deterime
ntal effect on molecular weight. After a short induction period the ra
ther slow polymerization of D,L-Lactide resulted in a maximal molecula
r weight followed by an almost constant value of molecular weight. (C)
1995 John Wiley & Sons, Inc.