【作者】 刘晓玲；

【导师】 孙举涛；

【作者基本信息】 青岛科技大学 ， 高分子化学与物理， 2018， 硕士

【摘要】 微晶纤维素（Microcrystalline Cellulose,MCC）是一种来源广、成本低、可再生、可降解、低密度的绿色填料,其作为一种绿色填料在橡胶工业的应用已经引起了广泛关注。但MCC粒径大（20⁹0μm）、极性高,与非极性的橡胶基体的相容性较差,因此补强效果较差。本论文采用吸附相反应技术,在溶胀的MCC表面“嵌入”和“包覆”纳米SiO₂,得到MCC-纳米SiO₂杂化体,以改善其对橡胶的补强作用。系统研究了杂化体制备工艺对杂化体结构、形态的影响,以及不同结构、形态的杂化体在绿色轮胎胎面胶中的应用规律。首先以氢氧化钠溶液或尿素溶液为溶胀试剂将MCC进行溶胀,然后基于吸附相反应技术原理,以MCC吸附的水膜为“微反应器”,通过溶胶-凝胶技术,在“微反应器”内生成纳米SiO₂,得到MCC-纳米SiO₂杂化体。研究结果表明以氢氧化钠为溶胀剂时,控制反应条件和微反应器尺寸,可以使杂化体中的SiO₂呈现球形、管状和棒状等不同形貌。而采用尿素为溶胀试剂时,杂化体中纳米SiO₂的形貌主要为球形,尺寸均匀、形状较为规则。将不同工艺制备的MCC-SiO₂杂化体应用于胎面胶中并取代部分白炭黑,研究其对胎面胶性能的影响规律。研究结果表明,与未改性的MCC相比,MCC-SiO₂杂化体在橡胶加工过程中可以原位微细化,并与橡胶基体具有较好的界面相互作用,明显提高胎面胶的物机性能和耐磨性能。动态力学性能测试表明,杂化体的加入还可以明显提高胎面胶的抗湿滑性,同时降低滚动阻力,因此MCC-纳米SiO₂杂化体是一种理想的胎面胶补强填料。另外,利用碱/尿素溶解MCC,然后将该溶液与天然胶乳混合,使纤维素在NRL中原位析出,制备纤维素纳米晶/天然橡胶（CNC/NR）复合材料。研究结果表明,通过控制纤维素的析出条件,可以得到CNC补强的NR复合材料。更多还原

【Abstract】 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.更多还原