INJECTION MOLDED ECO-FRIENDLY BIOCOMPOSITESFROM NATURAL FIBER AND CELLULOSIC BIO-PLASTIC

摘要

Natural fiber reinforced polymer composites (biocomposites) are emerging as a viable alternativeto glass fiber reinforced composites especially in automotive applications. It is estimated that ~75% of avehicle’s energy consumption is directly related to factors associated with vehicle’s weight, and it isidentified as critical need to produce safe and cost-effective light-weight vehicles. Auto companies areseeking lighter weight materials for fuel efficiency and are seeking materials with sound abatementcapability as well. Cellulose esters e.g. cellulose acetate (CA) plasticized with 30 wt.% citrate plasticizerhas been successfully reinforced with chopped hemp (HP) fiber to produce eco-friendly greenercomposite materials (CAP-HP based bio-composites) as future probable alternative to glass fiber basedcomposites for automotive applications. The usual extrusion processing followed by injection moldinghas been adopted in fabricating the bio-composites. Biocomposites with 30wt% of hemp contentexhibited an enhancement of flexural strength as much as 75% and modulus of elasticity (MOE) by250%. Intimate mixing resulting from the high shear forces in this type of processing is necessary toproduce superior strength bio-composites. Environmental Scanning Electron Microscope (ESEM) imagesof fractured impact sample indicate less fiber pullout indicating better adhesion between hemp fiber andCA matrix under these processing conditions. The cellulosic plastic composites under investigations haveproven to be a better matrix compared to polypropylene (PP) for natural fiber reinforcements.