Manipulation of non-isothermal crystallization kinetics of poly(lactic acid) composite film by a novel nucleating agent

Abstract

As a type of renewable and biodegradable polymer, poly(lactic acid) (PLA) has been widely used in various fields. However, its weak crystallization ability deteriorates the properties of the final product. In this work, a novel nucleating agent (MWCNTs@CeO₂), multi-walled carbon nanotubes (MWCNTs) decorated with ceria (CeO₂), was synthesized using the hydrothermal method and subsequently used to manipulate the non-isothermal crystallization kinetics and nucleation behavior of PLA. The results show that MWCNTs@CeO₂ can act as an effective nucleating agent to accelerate the crystallization rate of PLA by reducing the half-crystallization time. In non-isothermal crystallization kinetics, the Avrami equation modified by Jeziorny cannot accurately describe the non-isothermal crystallization behavior of PLA and PLA/MWCNTs@CeO₂ composite films, whereas the Mo method can. Furthermore, it is found that the addition of MWCNTs@CeO₂ does not change the crystal structure of PLA, but increases the nucleation and growth rate of PLA, thereby promoting its crystallization.