EFFECTS OF HETEROGENEITY OF MICROCRYSTALLINE CELLULOSE WITH NANO-SiO2 ON ITS APPLICATION IN TIRE TREAD COMPOUNDS

Heterostructures of microcrystalline cellulose-SiO 2 nanoparticles (MCC-SiO 2 ) were prepared by adsorption phase reaction technology (APRT). A urea solution served as the adsorption phase in the swelling process of the MCC particles. The thickness of the urea solution layer that adsorbed on the MCC surface was controlled by washing the samples with ethanol 3 times. The urea layer acted as a "microreactor" to generate SiO 2 nanoparticles through a sol-gel process with tetraethoxysilane (TEOS), and MCC-SiO 2 heterostructures took shape. The morphologies of the heterostructures were controllable by changing the swelling time, thickness of the urea layer and TEOS content. The SiO 2 particles loaded on the MCC surface were almost spherical, with a size of 20-40 nm. These heterostructures were used in tire tread compounds to show their potential as reinforcing fillers. Compared with vulcanizates filled with MCC, those filled with the heterostructures had improved mechanical properties, with a 16.7% increase in tensile strength and a 16.2% increase in tear strength. Furthermore, the heterostructures were found to be a good filler for addressing the "magic triangle" problem in the tire industry. These materials improved the wet-skid resistance and abrasion resistance, and decreased the rolling resistance. These results indicated that MCC-SiO 2 heterostructures are a potential filler for use in the tire industry. SEM photographs showed that the sizes of the MCC-SiO 2 heterostructures were micronized in situ during rubber processing, from 20-90 m to 1-10 m, and the interfacial bonding between the heterostructures and the rubber matrix was improved.