Nucleation and Crystallization in Bio-Based Immiscible Polyester Blends

Abstract

Bio-based thermoplastic polyesters are highly promising materials as they combine interesting thermal and physical properties and in many cases biodegradability. However, sometimes the best property balance can only be achieved by blending in order to improve barrier properties, biodegradability, or mechanical properties. Nucleation, crystallization, and morphology are key factors that can dominate all these properties in crystallizable bio-based polyesters. Therefore, their understanding, prediction, and tailoring are essential. In this work, after a brief introduction about immiscible polymer blends, we summarize the crystallization behavior of the most important bio-based (and immiscible) polyester blends, considering examples of double-crystalline components. Even though in some specific blends (e.g., polylactide/polycaprolactone) many efforts have been made to understand the influence of blending on the nucleation, crystallization, and morphology of the parent components, there are still many points that have yet to be understood. In the case of other immiscible polyester blend systems, the literature is scarce, opening up opportunities in this environmentally important research topic.