A Theoretical and Experimental Kinetic Investigation of the ROP of L,L-Lactide in the Presence of Polyalcohols

Summary The present work deals with the experimental and theoretical investigation of the ring-opening polymerization of L,L-lactide with stannous octoate as a catalyst for the production of high molecular weight polymers with improved physical and mechanical properties. The polymerization of L,L-lactide was experimentally studied at various temperatures and different monomer to initiator concentration ratio values. Subsequently, co-initiators with different number of hydroxyl groups (i.e., 1,4-butanediol, glycerol, di-trimethylolpropane and polyglycidol) were utilized to obtain branched or star shaped polymers. A comprehensive mathematical model was developed based on a detailed kinetic mechanism to predict the dynamic evolution of monomer conversion and molecular weight averages (i.e., Mn, Mw of PLLA). The predictive capabilities of the mathematical model are demonstrated by a direct comparison of model predictions with literature and new experimental data on monomer conversion as well as number and weight average molecular-weight of PLLA.