Exploring the Size Effect of Graphene Oxide on Crystallization Kinetics and Barrier Properties of Poly(lactic acid)

Two different sizes of graphene oxide/poly(lactic acid) composites were prepared by the solution flocculation method, and the effect of the size effect of graphene oxide on the crystallization, barrier, and mechanical properties of poly(lactic acid) was investigated by various characterization methods. The results of the crystallization behavior test show that the size change of graphene oxide has little effect on the nucleation effect of poly(lactic acid). Increasing the size of graphene oxide can promote the crystal growth, so as to improve the crystallization ability of poly(lactic acid). The test results of mechanical properties and barrier properties show that increasing the size of graphene oxide can provide a larger interfacial surface area and transmit stress more effectively, which can greatly improve the modulus of poly(lactic acid). At the same time, because of this, the diffusion path of gas molecules in poly(lactic acid) can be longer and more tortuous, so as to improve the barrier performance of poly(lactic acid).