New nanocomposite materials reinforced with cellulose nanocrystals in nitrile rubber

Cellulose nanocrystals (CNs) were fabricated from sulfuric acid hydrolysis of cottonseed linter. The crystals were then utilized to prepare nitrile rubber (NBR)/CNs nanocomposites by mixing a water suspension of CNs and the NBR latex directly. CNs formed a strong filler-filler network in the NBR matrix which resulted in an obvious “Payne effect”. The mechanical performance showed that CNs have a good reinforcing effect on NBR. The composites exhibited an increase of tensile strength from 7.7 to 15.8 MPa with the CNs content increasing from 0 to 20 phr. The scanning electron microscope (SEM) images showed that CNs dispersed in NBR matrix uniformly, which contributed to the considerable mechanical properties of the resultant composites. The results of dynamic mechanical analysis (DMA) demonstrated that the glass transition temperature (Tg) of the composites was shifted from 10.8 to 17.2 °C with CNs content increasing to 20 phr，and the storage modulus increased simultaneously. Thermal gravimetric analysis (TGA) result shows that the degradation corresponding to CNs in NBR/CNs nanocomposites is much higher than the degradation temperature of pure CNs.