Enhanced mechanical properties of styrene–butadiene rubber with low content of bacterial cellulose nanowhiskers

Styrene–butadiene rubber (SBR) nano-composites were prepared through mixing SBR latex with bacterial cellulose whiskers (BCWs). BCWs were extracted from the residual bacterial cellulose (BC) that was treated with acid hydrolysis. A rod-like nanofiber structure of BCWs was observed by transmission electron microscopy and atomic force microscopy. BCWs maintained the crystal structure in BCWs/SBR nano-composites as confirmed by X-ray diffraction patterns. The dispersion of BCWs in SBR matrix was further detected with field emission scan electron microscope. BCWs acted as a multifunctional physical cross-linker in the SBR matrix, the combination of BCW reinforcement and increased effective cross-linking density of the rubber network with incorporating BCWs would cause a more effective transfer of stresses from matrix to filler. Compared with neat SBR, the tensile strength and tear strength of SBR/BCW nano-composite with 2.5 phr (parts per hundred rubber) BCWs were increased by 319% and 182%, respectively.