Study on properties of polymer blends from polypropylene with polycaprolactone and their biodegradability

The main problem in preparation of polymer blends is compatibility between polymers mixtures with different properties. This paper describes properties of polymer blends prepared from modified polypropylene (PP) and poly-e-caprolactone (PCL). The preparation of these polymer blends involves modification of PP by oxidation with hydrogen peroxide. A part of the polymer blends consisting oxidized PP and PCL was compatible polymer blends, and the highest compatible polymer blends was obtained in the PP/PCL ratio of 70/30 (% w/w) with low crystallinity. The mechanical properties of polymer blends decreased with increasing of PCL proportion in the polymer blends. Enzymatic degradability of PP-PCL polymer blends were lower than that of PCL, and increased slowly with increasing of PCL content in the polymer blends. The use of oxidized PP in preparation of polymers blends with PCL effectively improves the degradability of the polymer blends due to the increase of compatibility of each component in polymer blends. Furthermore, biodegradation process might occur through hydrolysis of PCL and compatible parts of polymer blends to result in hydroxyl and carboxylate functional groups in the end of polymer chain.