Fabrication of poly(lactic acid)/graphene oxide/stearic acid composites with improved tensile strength

For the purpose of the development of poly(lactic acid)/graphene oxide composites with improved tensile properties, a stearic acid compatibilizer was used to enhance the compatibility of the graphene oxide sheets with the poly(lactic acid) polymer matrix. Graphene oxide was modified with stearic acid at different mass ratios of 1:1, 1:3, and 1:5 prior to forming the composites with poly(lactic acid). Characterization showed positive effects of stearic acid attached to GO in every mass ratio and also enhanced compatibility with the poly(lactic acid) matrix. Stearic acid could strengthen the interfacial interactions between the flat graphene oxide sheets and the poly(lactic acid) matrix resulting in improved tensile strength. The tensile strength of the poly(lactic acid)/graphene oxide/stearic acid composite with a mass ratio of graphene oxide and stearic acid 1:1 increased by 32% compared to poly(lactic acid) alone. Based on these results, the graphene oxide/stearic acid composites show potential for use as nanosheet fillers for tensile strength enhancement in poly(lactic acid). POLYM. COMPOS., 38:2272–2282, 2017. © 2015 Society of Plastics Engineers