Study On The Graft Polymerization Of ε-Caprolactone Onto Poly (Vinyl Alcohol), Polypropylene And Pet

Poly(ε–caprolactone)(PCL) has been extensively used as biomaterials and carriers for drug delivery systems because of its excellent biocompatibility, biodegradation and low toxicity. As the interest becomes greater, scientists try to develop new kind of environmentally friendly materials through block polymerization, graft polymerization, and blend systems from PCL with popular polymers such as PP, PE, PVA etc.In this paper, we study the graft polymerization of ε–caprolactone (ε–CL) onto different substrates such as poly(vinyl alcohol) (PVA), polypropylene (PP) film and polyethylene terephthalate(PET) film. The graft polymerization of CL onto PVA film was carried out at 100～130℃ in bulk system in the presence of Bu3SnCl, Sn(Oct)2, or without any catalyst. The grafted polymer,poly(vinyl alcohol)-graft-polycaprolactone (PVA-g-PCL), was characterized by grafting percentage,SEM and ATR FT-IR. The effects of reaction time and different catalysts on the grafting percentage were studied. It was found that the grafting percentage is highest in absence of initiator. The waterproofness of grafted film increases with the increasing of grafting percentage. The graft polymerization of CL onto PVA in solution system was also studied in this article.We also studied the graft polymerization of CL onto commercial polypropylene film which has not been modified previously on its surface. The influence of the reaction temperature, reaction time and monomer concentration on the grafting polymerization was discussed. The results show that the PP film loses weight after the graft polymerization takes place. The grafted polymer, PP-g-PCL, was also characterized by ATR and SEM.The graft polymerization of CL onto PET film was also investigated. The graft polymerization was carried out through ring-opening polymerization using stannous octoate as catalyst in solution medium. The influence of solvent, reaction time and monomer concentration on the grafting percentage was discussed. The result indicated that the grafting percentage is highest when toluene and heptane were used as mixture solvents. The grafting percentage increases with the increasing of reaction time and monomer concentration. The grafted film was characterized by ATR and SEM.