Preparation of rigidity toughness balance and stable poly(glycolic acid) based on chain extension reaction

Abstract

As a completely degradable material, poly(glycolic acid) (PGA) has excellent rigidity, barrier properties, degradability and biocompatibility. However, the inherent brittleness and easily hydrolysable characteristics limit its widespread application. Herein, we introduced chain extension ADR to modify PGA to ameliorate these defects. The results showed that ADR could react with PGA to form “comb‐like” and “cross‐linked” chain extension structures resulting in the improvement of complex viscosity and formation of gel. Because of the chain entanglement of chain extension structures, the toughness of modified PGA was improved (which was verified by the impact strength value of 4.3 kJ/m2 that was about 126% of virgin PGA) without sacrificing its rigidity. Furthermore, the hydrolysis results indicated that the representative PGA/1.0ADR had better hydrolysis stability, it had more complete morphology and slower degradation rate than virgin PGA in the 17‐day hydrolysis experiment. Apart from better toughness and hydrolysis stability, there was also improvements in crystallization performance, the sample PGA/1.0ADR endowed with higher crystallization peak temperature (2.3°C higher than virgin PGA) and lower crystallization activation energy. In short, this work prepared a kind of modified PGA with rigidity toughness balance and better hydrolysis stability, which could expand the application range of PGA‐based materials.

Preparation of Nonlinear Structure Poly(glycolic acid) with High Toughness, Excellent Hydrolysis Stability, and Foaming Performance

“…Many studies show that the introduction of a nonlinear structure in the polymer can improve the toughness , and slow down the degradation rate. − Moreover, in our previous study, the nonlinear structure PGA modified by chain extender ADR (styrene-acrylonitrile-glycerol methacrylate copolymer) also had the same improvement …”