Miscible Blends of Two Crystalline Polymers. 2. Crystallization Kinetics and Morphology in Blends of Poly(vinylidene fluoride) and Poly(1,4-butylene adipate)

Abstract

The crystallization kinetics and morphology in miscible blends of poly(vinylidene fluoride) (PVF2) and poly(1,4-butylene adipate) (PBA) have been investigated using optical microscopy and differential scanning calorimetry. Blends of PVF2 and PBA are unique in the sense that both components are capable of crystallization over a wide range of compositions. The kinetics of crystallization of both PVF2 and PBA in these blends have been investigated. During the crystallization of the high-Tm component (PVF2, Tm ≈ 175 °C), the low-Tm component (PBA, Tm ≈ 60 °C) acts as a noncrystalline diluent. Addition of PBA depresses the radial spherulitic growth rate and overall crystallization rate of PVF2 and affects the texture of PVF2 spherulites but does not significantly alter the nature of the nucleation and growth processes of this polymer. During the crystallization of PBA, the PVF2 phase is always partially solidified and the presence of the spherulitic microstructure of PVF2 profoundly influences the crystallizat...