Preparation and properties of polylactide/nano-silica in situ composites

Purpose - Polylacticle/nano-silica in situ composites are synthesised and characterised in order to study their mechanical and thermal properties. The purpose of this paper is to study these properties and compare them with the pure polylacticle (PLA). Design/methodology/approach - Polylacticle/nano-silica in situ composites are synthesised from lactide and modified nano-silica using stannous octoate as a catalyst. The structure and properties of the composites are characterised by gel permeation chromatography (GPC), thermal gravimetric analysis (TGA) and scanning electronic microscopy (SEM). Findings - The results of SEM showed that nano-silica and PLA are connected with covalent bonds, and that inorganic phases are dispersed homogeneously in the PLA matrix. The results of TGA indicated that the thermal decomposition temperature rose with the increase of silica content. The tensile strength of the composites is enhanced because of the addition of nano-inorganic particles into PLA. Research limitations/implications - Although the preparation process is simplified by a two-step method, attempts will be made to synthesise the polylactide/nano-silica composites by a one-step approach to curtail the preparation cycle. Practical implications - The composites are expected to be suitable for applications in packaging materials, biomedical and pharmaceutical fields. Originality/value - Preparation of polylactide/nano-silica composites is expected to exert the respective advantages of the two ingredients and to produce more practical polymer materials.