Mechanical and biodegradability studies of toluene - 2,4 - diisocyanate (TDI) modified okra fiber reinforced polyester composite

Abstract

The compatibility of natural fiber in a synthetic matrix is an important factor affecting bio-composite properties. Several methods have been used to enhance the fiber matrix interface, however, the use of toluene-2,4-diisocyanate (TDI) though recommended in literature, has gained little attention. This study, therefore, presents the mechanical and biodegradability properties of TDI modified Okrafiber as reinforcement in unsaturated polyester resin. Short okrafiber of average length 5 mm was modified with the TDI concentration varied from 0 to 4 wt% at1 wt% intervals. The modified fiber was then used to reinforce the unsaturated polyestermix using the casting method and compressed under 350 N. Mechanical tests (such tensile impact, hardness and water absorption) were conducted on the fabricated composites using ASTM standards. Weight loss coupled with Surface Morphological studies was used to estimate the biodegradability of the fabricated composites. Increase concentration resulted in improvement intensile strength, percentage elongation and water resistance of the composites (The maximum average tensile strength of 149.23 Mpa and a percentage elongation of 9.6% was recorded at 3% TDI concentration) while hardness and modulus of elasticity reduced. The water absorption capacity of 1.09% was recorded at 4% TDI concentration.0 wt%, 1wt% and 2 wt% TDI modifications was buried and significant biodegradation was observed after 90 days sample burial with 2% treatment recording the highest weight loss of 0.15%. These properties will find application in indoor furniture panels, footboards and platforms.