Poly (lactic acid)/modified gum arabic (MG)based microcellular composite foam: Effect of MG on foam properties, thermal and crystallization behavior

The article demonstrates a simple and innocuous method for fabrication of poly (lactic acid) (PLA)/modified gum arabic (MG)based hydrophobic, microcellular, highly porous and interconnected composite foam. The observed density of the composite foams was remarkably reduced by ~86% in comparison to PLA granules. Further, there was noticed an increase in cell density and a decrease in cell size due to the addition of MG nanofiller. The thermogravimetric analysis (TGA) of developed foam showed no significant effect of MG in maximum degradation temperature (T_max). Dynamic mechanical analysis (DMA) and differential scanning calorimetry (DSC) investigations suggested the plasticizing effect of MG nanofiller in the PLA matrix. The hydrophobicity of fabricated foam was found to increase with an increase in loading of MG and an increment of ~20° in contact angle was observed for highest loading of MG (3%) in comparison to neat PLA foam. Further, an increase in the surface area up to ~60% and a decrease in pore diameter up to ~53% were observed for PLA/MG based foam by porosimetric investigations. Based on this investigation, the fabricated PLA/MG based foams have the potential for specialized applications as an alternative to non-degradable petro-based foams in various fields of life.