Poly(L-lactic acid)/deproteinized natural rubber blends with enhanced compatibility

Abstract

PLLA-g-LMWNR (LMWNR - low molecular weight natural rubber) was used as a compatibilizer (1-3 wt %) of poly(L-lactic acid)/deproteinized natural rubber (PLLA/DPNR) blend (95/5 w/w). The LMWNR was prepared using TiO2/ZnO (9: 1 w/w) and H2O2 as co-catalyst. The obtained LMWNR was grafted with 0-12 wt % maleic anhydride (LMWNR-g-MA) and then with PLLA (PLLA-g-LMWNR). A significant improvement in the mechanical properties of the PLLA/DPNR blend was found in the blend that contained 3 wt % PLLA-g-LMWNR. Scanning electron microscopy showed a decrease in the pore diameter from 5.44 to 1.56 µm. The thermal analysis of PLLA/DPNR blends showed that the Tg value of PLLA phase shifted from 63.1 to 61.4°C. These results confirmed that PLLA-g-LMWNR can enhance the compatibility of the PLLA/DPNR blend.