无机成核剂改善聚乳酸结晶性能的研究进展

摘要

As a semi-crystalline polymer,polylactic acid (PLA)has a excruciatingly low crystallization rate,which makes PLA crystallize negligibly during the forming process,and consequently to a large extent attenuates the product's heat resistance and other properties.Hence the shortcoming mentioned above can be overcome by improving PLA's crystallization,to which the addition of inorganic fillers is an effective approach.This paper aims to summarize the preparation of variety of composite materials with ex-cellent crystallization performances by blending PLA with different types of inorganic nucleating agent fillers.The inorganic nuclea-ting agent dispersed in the PLA matrix act as a nucleation site to increase the nucleation density.The molecular interaction force,the high orientation of the molecular chain,and the satisfied crystallinity lead to the increment of melting enthalpy and the decline of melting entropy,and thereby benefiting the PLA'S heat resistance.%聚乳酸(PLA)是一种半结晶聚合物,结晶速率非常慢,在实际成型加工过程中几乎不结晶,这在很大程度上影响了聚乳酸的耐热性等性能,故可通过改善结晶性能来改善聚乳酸耐热性等性能.添加无机填料是改善聚乳酸结晶性能行之有效的途径.本文主要介绍了以无机填料为成核剂,将其与PLA共混制备结晶性能优良的复合材料.无机成核剂分散在聚乳酸基体中,成为成核位点,增加成核密度;分子间作用力、分子链较高的取向程度以及较高的结晶度使材料的熔融焓增大、熔融熵减小,从而改善PLA的耐热性.