Abstract: Research and development of biodegradable materials is one of the effective approaches to solving the environmental pollution problems which come from the traditional petroleum-based plastics. Polylactic acid (PLA) has so many good properties such as full biodegradability，good thermal processibility，renewablility，high mechanical performance and so on. It is an inevitable trend to replace the petroleum-based plastics. However，the properties of hydrophobicity，poor toughness and high price are obstacles for the application of PLA. All of these result in attracting much attention in the research of modification of PLA. In this paper，the recent research on biodegradable PLA system including blending with natural polymer and synthetic polymer is summarized. The effect of processing technology，surface treatment and additives on the composite material is presented. Further research could be flexible polymer，surfactant，and various fibers to improve the brittleness，compatibility，and strength of the cromposite material.

Key words: polylactic acid, biodegradable, blending modification

摘要： 生物可降解高分子材料的研究开发是解决石油基塑料对环境污染的有效方法之一。其中，聚乳酸（PLA）具有可完全生物降解、可加工、可再生、力学性能优良等特点，是代替石油基塑料的必然趋势。但是PLA的疏水性大、性脆、价格贵等缺点限制了其应用和发展。论文主要综述了近年来国内外有关聚乳酸与天然高分子共混、合成高分子共混改性的研究进展，介绍了加工工艺、表面处理、添加剂等对复合体系性能的影响。在现有研究成果的基础上，可以通过加入柔性高分子、表面活性剂、纤维等以改善复合材料的脆性、相容性以及强度，以推动聚乳酸基复合材料的广泛发展。

关键词: 聚乳酸, 生物降解, 共混改性