Crystallization, rheological and mechanical properties of poly(butylene succinate)/poly(propylene carbonate)/poly(vinyl acetate) ternary blends

Herein, a ternary blend from poly(butylene succinate) (PBS), poly(propylene carbonate) (PPC), and poly(vinyl acetate) (PVAc) with improved crystallization rate, stiffness, and toughness was initially prepared via melt compounded. The influence of PVAc content on morphology, miscibility, thermal behavior, and rheological and mechanical properties was investigated. Scanning electron microscopy observation showed phase morphology of PBS/PPC/PVAc ternary blends evolved from sea-island dispersion to co-continuous structure. Dynamic mechanical analysis revealed that PBS and PPC were immiscible. The presence of PPC inhibited the crystallization of PBS, while simultaneous incorporation of PVAc and PPC promoted the crystallization. Furthermore, the introduction of PPC and PVAc enhanced the rheological properties of PBS. Unexpectedly, prominent improvement in tensile modulus, yield strength, and elongation was obtained for the PBS/PPC/PVAc ternary blend with 10 wt% PVAc due to the morphological evolution from sea-island to co-continuous structure, which was respectively increased by 93%, 52%, and 26% compared with neat PBS.