Ring Opening Polymerization of L-lactide;An Investigation on Influence of Reaction Time on Monomer Conversion and Viscosity Average Molecular Weight

Ring opening polymeization of L-lactide is carried out in presence of stannous octoate as a catalyst and triphenylphosphine as a cocatalyst via bulk melt polymerization.All experimental is carried out in constant temprature (T=170˚C) and catalyst concentration and in the different times.the ratio of catalyst to monomer is 2000ppm and equal ratio of catalyst to cocatalyst is added.Ubbelohde Viscometer is used to measure viscosity average molecular weight (Mv).Monomer conversion and Mv is improved in the optimum time that is reported in this paper.IR is used to prove the functional groups of PLA