Studies on processing morphology Evolution and industrial Applications of poly lactic acid Based bio composites

Abstract

Poly (Lactic Acid) (PLA) is though a synthetic biodegradable polymer, we considered it as a coating material on industrial Kraft paper substrates to impart barrier against air, grease and water. This is an initiative to replace the existing non- biodegradable coating materials such as acrylic and varnish used for the same purpose in many industrial products such as packaging, coated abrasives, etc. In this study, the effect of crystallinity of PLA on the barrier properties is evaluated. Semi crystalline PLA (sc-PLA) showed better barrier properties over its amorphous counterpart and also against the conventionally used barrier coating materials, such as acrylic and varnish, on identical paper substrates under identical process conditions. Sc-PLA is comparatively evaluated against PCL and PEG, found to serve as an ideal barrier coating material on Kraft paper. Further, PLA was applied as a barrier coating material on natural Kraft paper to fabricate coated abrasive products to replace the synthetic barrier coatings. The data from different studies revealed that the PLA with a coating weight of 9 g m-2 appeared to be the most ideal concentration and superior in overall barrier properties essentially needed for the fabrication of coated abrasive products. Furthermore, fabrication of industrially valuable coated abrasive and packaging products are made using bio-polymeric blends of PLA-PEG in Ethyl Acetate (EA) solvent to produce an environmentally safe PLA-PEG coating and film formulation in EA. The PLA-PEG (10%) formulation demonstrated its dual purpose industrially valuable applications as both coated abrasive and packaging products newline