Great enhancement of mechanical features in PLA based composites containing aligned few layer graphene (FLG), the effect of FLG loading, size and dispersion on mechanical and thermal properties

Abstract: Four series of PLA based composite films containing horizontally aligned few layer graphene (FLG) flakes of high aspect ratio and adsorbed albumin are prepared. The mechanical and thermal properties vary with percentage, dispersion degree and size of FLG flakes. Great improvement up to 290 and 360% of tensile modulus and strength respectively was obtained for the composite containing high lateral size of FLG at 0.17% wt., and up to 60 and 80% for the composite with very well dispersed 0.02% wt. FLG. The composites of PLA and PEG-PLLA containing very well dispersed FLG flakes at 0.07 % wt. are ductile showing enhancement of elongation at break up to respectively 80 and 88%. Relatively high electrical conductivity, 5 x 10-3 S/cm, is measured for PLA film charged with 3% of FLG.