Fabrication and Characterization of Hybrid Bio‐Composites of Poly(vinyl alcohol)/Poly(<i>L</i>‐lactic acid) Blends With Cotton and Bleached Jute

ABSTRACT First, due to the brittle nature of the PLLA‐fiber (poly( L ‐lactic acid)‐fiber) composite and then the poorer physical properties of the PVA‐fiber (Poly(vinyl alcohol)‐fiber) composite, composites with balanced properties were prepared using PVA, PLLA, and cotton or bleached jute. Here PVA and PLLA will serve as matrices while composites of PVA/PLLA/Cotton or bleached jute were prepared with different compositions (85/10/5), (70/20/10) and (55/30/15). The composites' physical, mechanical, thermal, and morphological properties were analyzed. Composites with larger amounts of PVA have higher water absorption capacities while composites with higher amounts of PLLA exhibit greater bulk densities. Tensile strength and elongation of PVA/PLLA/Cotton composites decrease with an increase in fiber loading, whereas that of PVA/PLLA/Bleached jute composite increases with fiber loading up to 10%, followed by a decrease. Young's modulus diminishes when the percentage of fiber in the composites increases. The peak temperature related to the second step of decomposition for the neat matrix was highest for the composite containing 10% of cotton and lowest for the 15% jute. Thermal expansion coefficient decreases with increasing fiber percentages. SEM images show that interfacial adhesion between PVA/PLLA blends with bleached jute is stronger than that of cotton fiber; cotton fiber reinforced composites reveal fiber slips during failure.