Preparation and Properties of Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) and Polypropylene Grafting Maleic Anhydride Two-Component Materials

Abstract

In order to provide a theoretical basis for the preparation and spinnability of two-component materials, poly(3-hydroxybutyrate-co-3-hydroxyvalerate)(PHBV) and polypropylene grafting maleic anhydride (PP-g-MAH) blends were prepared by melt mixing with different ratios (100/0, 75/25, 50/50, 25/75, 0/100). Properties of the blends system were investigated by means of a mixed rheometer, scanning electron microscope, simultaneous thermal analyser, differential scanning calorimetry and X-ray diffraction. The results demonstrate that PHBV/PP-g-MAH blends exhibit different morphology of the sea-island with a change in the mix ratio. The initial thermal decomposition temperature of PHBV in the blending system is over 250 °C, which means the thermal stability of PHBV is markedly improved. The crystallisation of PHBV varied according to the blending process parameter. When the cooling velocity increases, the crystallisation peak becomes wide, the temperature of crystallisation decreases, and the crystallisation temperature of PHBV increases significantly. PHBV has a high sensitivity to variation in the shear rate, and PHBV/PP-g-MAH blends have the mixing characteristic of shear thinned liquid. There is no diffraction peak at 2θ = 22.8°, and this result certifies that PP-g-MAH changes the crystal form of PHBV. and that PP-g-MAH addition is beneficial to the spinnability of PHBV. Results show that the interplay between PHBV and PP-g-MAH is of great significance and universal for both plastics and fibres.