Production of micro-lignocellulosic fibril rubber composites and their application in coated layers of building materials

Abstract

Novel composite materials were made by combining micro-lignocellulosic fibrils and natural rubber applied as spray coated layers for building materials. The micro-lignocellulosic fibrils were produced based on the mechanical pulping process with jute bast as the raw material. The obtained micro-lignocellulosic fibrils had a good content of water-suspended materials with fibril widths of about 0.1 to 1.0 µm and fibril length of about 100 to 150 µm. The composites were produced using natural rubber mixed with the micro-lignocellulosic fibrils at 0, 5, and 10 parts per hundred of rubber, vulcanizing sulfur, and activated zinc oxide. The fibril-rubber suspension was formed in the composite sheets with a thickness of 0.5 to 1.5 mm using a spray coating technique and was oven-dried at 100 °C. The rubber composite had a homogenous fibril distribution in the rubber composite matrix, with good bonding between the fibrils and the rubber polymers. The fibrils contributed to the strength reinforcement of the rubber composite layers. The application of the micro-lignocellulosic fibril rubber composites coated onto industrial fiber cement boards enhanced the thermal insulation properties, which had a lower degree of thermal conductivity and heat diffusivity and enhanced the toughness and waterproofing of the fiber cement boards.