Preparation Of The Microcrystalline-nano SiO₂ Hybrid And Its Application In Rubber Materials

As a kind of“green filler”in rubber materials,microcrystalline cellulose?MCC?has the advantages of abundant resources,low price,renewability,biodegradability and low density,and thereby had drawn extensive attention in recent years.However,it has poor interaction with rubber matrix due to its big size and strong polarity,which resulted in the deteriorated performance of it rubber composites.MCC-nano SiO₂hybrid materials were prepared by loading nano-SiO₂ on the swollen MCC by the adsorption phase reaction technique to improve its reinforcing efficiency in rubber composites.The effects of fabrication process on the structure and morphology of hybrid materials was studied.Meanwhile,the hybrid materials with different structure and morphology were used in the tire tread compounds and its effects on the performances of the compounds was investigated.First,MCC was swollen by using NaOH aqueous solution or urea aqueous.The MCC-SiO₂ hybrid materials were then obtained by an adsorption phase reaction technique,which the lye layer absorbed by swollen MCC was used as the micro-reactor to form nano-Si O₂ particles by the sol-gel technique.The results showed that the morphology of nano-SiO₂ in the hybrids could be spherical,tube-like or rod-like when NaOH aqueous solution was used as the swelling agent.However,spherical,well-distributed Si O₂ particles were obtained in hybrids when urea aqueous was used as the swelling agent.The different MCC-SiO₂ hybrid materials were used in the tire tread compounds to investigate their influences on the performance of tread compounds.The results indicated that the sizes of MCC-SiO₂ hybrids were in situ decreased during the rubber processing,together with the improved interface adhesion between MCC-SiO₂ hybrid and rubber matrix,which contributed to the improvement of the physio-mechanical properties and abrasion resistance of the vulcanizes.Dynamic mechanical analysis?DMA?showed that the tire tread compounds could achieve a high wet-skid resistance while maintaining a low rolling resistance by using MCC-SiO₂ hybrid materials to replace parts of silica.CNC/NR composites were also prepared by in situ precipitation of natural latex with cellulose solution.The results showed that cellulose nanocrystal?CNC?could be separated from cellulose solution to NR phase and formed CNC/NR composites.