Poly(glycolic acid) with Enhanced Mechanical and Foaming Properties Obtained by Biobased Cashew Phenol Glycerol Ether

Abstract

In this study, nonlinear poly(glycolic acid) (PGA) was successfully prepared by using the biobased chain extender cashew nut phenol glycerol ether (ECA) and the initiator 1,4-bis(tert-butyl peroxy diisopropyl) benzene through the cooperation reaction of functional groups. The modified PGA exhibited better toughness, stability, and foaming properties. It was observed that the modified PGA with 2.0 wt % ECA (G/1.0B/2.0E) showed the highest degree of nonlinearity, with notched impact strength (4.5 MPa) and elongation at break (36.1%), which were 18.4 and 113.6% higher than that of virgin PGA. In addition, the oxidation onset temperature and oxidation induction time of G/1.0B/2.0E were increased to 312.8 °C and 15.7 min compared to 303.5 °C and 5.1 min for virgin PGA. The in vitro degradation results revealed that G/1.0B/2.0E took longer to reach the same level of degradation than virgin PGA, and the degradation rate of G/1.0B/2.0E became significantly slower compared with that of virgin PGA at the later stage of degradation. Furthermore, G/1.0B/2.0E exhibited a favorable foaming performance with a 2.8 expansion rate. Therefore, the present study provides a green route for the preparation of nonlinear PGA with good toughness, degradation stability, and foaming properties.