Polylactide/modified layered silicates nanocomposites: A critical analysis of morphological, mechanical and thermal properties

Abstract

Polylactide/organically modified layered silicate nanocomposites were fabricated using melt blending technique in a twin screw extruder. Variation in mechanical properties and thermal stability with the addition of three types of commercial nanoclays namely Cloisite 15A, Cloicite 25A, Cloicite 93A in polylactide were investigated. It was observed that the tensile, flexural and impact properties of polylactide increase with increase in organically modified layered silicate from 1 to 7 wt%. Nanocomposites prepared with 5 wt% organically modified layered silicate exhibited optimum mechanical performance. Polylactide/C93A nanocomposites exhibited optimum mechanical performance as compared with virgin polylactide. Dynamic mechanical analysis indicated an increase in storage modulus (E′) with the incorporation of organically modified organoclays. Differential scanning calorimetry and thermogravimetric analysis thermogram in the nanocomposites also showed improved thermal stability when compared with virgin polylactide. X-ray diffraction studies showed an increase in overall d-spacing in polylactide/C93A nanocomposites indicating intercalated structure.