Chitin nanowhiskers from shrimp shell waste as green filler in acrylonitrile-butadiene rubber: Processing and performance properties.

In this work, chitin nanowhiskers with high crystallinity index were obtained from shrimp shells waste using acid hydrolysis method and then comprehensively characterized. Subsequently, the impact of chitin nanowhisker content on processing and performance of acrylonitrile-butadiene rubber based nanocomposites was evaluated. The results showed that the addition of chitin nanowhiskers increased tensile strength and tear strength of nanocomposites by 116 % and 54 %, which was related to suitable dispersion of chitin nanowhiskers in matrix. Reinforcing effect of chitin nanowhiskers in acrylonitrile-butadiene rubber was also confirmed by Wolff activity coefficient, glass transition temperature and equilibrium swelling measurements. Moreover, it was found that higher content chitin nanowhiskers significantly improve the thermal stability of studied nanocomposites. The incorporation of chitin nanowhiskers resulted in increase of 74 °C for onset degradation temperature. This work confirmed that shrimp shell waste can be upcycled into chitin nanowhiskers - promising green filler in NBR for high-performance elastomeric applications.

Green tire technology: Effect of rice husk derived nanocellulose (RHNC) in replacing carbon black (CB) in natural rubber (NR) compounding.

The effect of replacing carbon black (CB) by rice husk derived type-I nanocellulose (RHNC) in natural rubber vulcanization is presented in this study. The synthesized RHNC was characterized using various analytical techniques like FTIR, XRD, SEM, TEM, DLS, TGA etc. The cure characteristics, mechanical, technological, thermal, barrier and dynamic mechanical properties of the composites were analysed. The mechanical properties of the NR composites containing 30 wt% of CB are comparable with the composite containing 25 wt% of CB and 5 wt% of RHNC. The DMA studies show that the loss tangent (tan δ) at 60 °C is lower for the composite containing 5 wt% of RHNC and 25 wt% CB compared to the composite containing 30 wt% CB. This shows that RHNC can impart low rolling resistance, which is a crucial parameter for green tire applications.