摘要
以羟乙基纤维素 (HEC)和四甲氧基硅烷 (TMOS)为原料 ,利用溶胶 凝胶技术 ,通过TMOS在HEC水溶液中的水解 缩聚反应制得了HEC SiO2 凝胶材料。探讨了反应体系pH值、H2 O与TMOS的体积比率和HEC用量等因素对HEC TMOS水解 缩聚体系凝胶时间和光学性能的影响。借助差示扫描量热法考察了HEC SiO2 杂化材料的热性能 ,并利用扫描电镜观察了HEC凝胶与SiO2 凝胶复合前后的微观结构特征。结果表明 ,随着HEC用量和TMOS浓度的增大 ,水解 缩聚体系凝胶时间缩短 ,可见光透过率降低 ;随pH值的增大 ,可见光透过率降低 ,凝胶时间变化较为复杂 ;HEC SiO2 杂化材料是以HEC凝胶为柔性连续相 ,SiO2 凝胶为刚性分散相的两相体系 ,该体系热性能较好 ,玻璃化转变温度为 2
Hydroxyethyl cellulose/silicon dioxide(HEC/SiO 2)organic/inorganic hybrid materials are prepared by sol\|gel process through the hybrolysis and polycondensation of tetramethoxy\|silicane (TMOS) in hydroxyethyl cellulose aqueous solution. The effects of reaction system pH, volume ratio of water to TMOS, and HECcontent on the gelation time and optical property of the hybrid materials are investigated in detail. The heat performances and microscopical structure of HEC gel materials, SiO 2 gel materials and HEC/SiO 2 hybrid materials are studied by differential scanning calorimetry and scanning electron microscopy respectively. The results show that the gelation time and visible light transmittance of the above\|mentioned systems reduce when the HEC content and the density of TMOS increase. pH has a complex effect on the gelation time. The visible light transmittance of the systems reduces when pH increases. HEC/SiO 2 hybrid materials present two phase system in which HEC and SiO 2 gel materials are flexibly continuous phase and rigid dispersed phase respectively. The heat performance of the HEC/SiO 2 hybrid materials are good, and their glass\|transtion temperature is near to 235℃.
出处
《材料科学与工程》
CAS
CSCD
北大核心
2002年第1期11-14,25,共5页
Materials Science and Engineering
基金
西安交通大学科学研究基金资助项目XJJJ2 0 0 0 2 0
