The degree of crystallinity and segmental mobility in interpenetrating spherulites of poly(butylene succinate) and poly(ethylene oxide)

Abstract

The influence of poly(butylene succinate) (PBS) crystals on the crystallinity of poly(ethylene oxide) (PEO) in PBS/PEO blends, which exhibit interpenetrating spherulites, was examined. The degree of crystallinity, ϕ, of each component was obtained by pulsed nuclear magnetic resonance (NMR). The value of ϕ of PBS exhibited a maximum that was larger than that of the homopolymer, whereas PEO exhibited a nearly constant ϕ throughout the composition. The dilution effect, order of crystallization, and change in the glass transition temperature upon blending were discussed as factors contributing to the ϕ. PEO exhibited an apparent secondary crystallization, where ϕ gradually increased and the mobility of the chain segments was suppressed. The secondary process of PBS, on the other hand, was nearly negligible. The influence of poly(butylene succinate) (PBS) crystals on the crystallinity of poly(ethylene oxide) (PEO) in PBS/PEO blends, which exhibit interpenetrating spherulites, was examined. The degree of crystallinity, ϕ, of each component was obtained by pulsed nuclear magnetic resonance (NMR). The dilution effect, order of crystallization, and change in the glass transition temperature upon blending were discussed as factors contributing to the ϕ. PEO exhibited an apparent secondary crystallization, where ϕ gradually increased and the mobility of the chain segments was suppressed. The secondary process of PBS was nearly negligible.