Mechanical, barrier, and biodegradability properties of bagasse cellulose whiskers reinforced natural rubber nanocomposites

Cellulose whiskers were isolated from bleached sugar cane bagasse kraft pulp. The length of the isolated whiskers was in the range 84–102 nm while the width was in the range 4–12 nm. They were used as reinforcing elements in natural rubber (NR) matrix. The effect of whiskers loading on tensile properties, thermal properties, moisture sorption, water vapor permeation, and soil biodegradation was studied. Significant improvement of Young's modulus and tensile strength was observed as a result of addition of whiskers to the rubber matrix especially at high whiskers’ loading. Dynamic mechanical thermal analysis (DMA) and differential scanning calorimetry (DSC) results showed no change in the glass transition temperature (Tg) of the rubber matrix upon addition of cellulose whiskers but at softening of rubber, cellulose whiskers have reinforcing effect on the rubber. Presence of bagasse whiskers resulted in an increase in moisture sorption of rubber films up to 5% whiskers loading while at higher whiskers’ loading the moisture sorption tended to decrease. Barrier properties to water vapor decreased on increasing cellulose whiskers up to 7.5% whiskers loadings then increased with further increase in whiskers loading. Presence of cellulose whiskers increased the rate of degradation of rubber in soil.

Research highlights▶ The current research work is on utilization of bagasse, an important agricultural residue in some countries in the world, in isolation of cellulose whiskers and their use in nanocomposites using natural rubber as a matrix. The properties of prepared nanocomposites were characterized regarding their mechanical, thermal, moisture sorption, water vapor permeability, and biodegradability in soil.