Review on Modification of Poly (lactic acid) in Physical and Mechanical Properties
Abstract
Poly (lactic acid) (PLA), prepared from renewable resources such as corn and sugar beet, has good environmental friendliness, biocompatibility, bioabsorbability, biodegradability and energy saving. It is a polymer considered to replace traditional petroleum-based plastics. PLA has received widespread attention in recent years. However, PLA has defects such as high brittleness, poor heat resistance, poor hydrophilicity, low melt strength, and low tensile and flexural strength, which severely restrict the scope of PLA's application. Therefore, it is necessary to modify PLA to improve its toughness, thermal stability, hydrophilicity, melt strength and other mechanical properties in physical and mechanical properties. This article summarizes the toughening modification, heat resistance improvement, hydrophilicity improvement, melt strength improvement and other mechanical properties such as tensile strength improvement of PLA, respectively. The specific methods of PLA modification are summarized from the perspectives of chemical modification and physical modification.