Enhanced reinforcement efficiency in a hybrid microcrystalline cellulose–SiO2 filler for the tire tread composites

Microcrystalline cellulose (MCC) was swollen by NaOH aqueous solution and was incompletely dried to form a thin layer of NaOH solution around it. This NaOH layer was used as a “microreactor” to prepare the MCC–SiO2 hybrid filler by generating SiO2 particles on the MCC surface when tetraethoxysilane (TEOS) was used as a precursor. The effects of the TEOS amounts on the morphologies and loading ratio of the MCC–SiO2 hybrid filler were studied. The results showed that SiO2 particles or SiO2 coating were loaded uniformly onto the MCC surface and the SiO2 particles’ morphologies, and loading ratios of can be controlled by the amount of TEOS. The MCC–SiO2 hybrid fillers were later used in silica/SSBR compounds to replace a fraction of the silica, and their effects on the physico–mechanical and dynamic properties were discussed. The results showed that the vulcanizates with MCC–SiO2 hybrid filler exhibited improved physico–mechanical and dynamic properties relative to the control sample, and their compression heat build-up was also clearly reduced. The SEM photos of vulcanizates showed that the interface adhesion between MCC–SiO2 and the rubber matrix was improved and furthermore the sizes of MCC–SiO2 were decreased in situ during rubber processing.