摘要
采用溶胶一凝胶法,以正硅酸乙酯(TEOS)为前驱体,添加聚氧乙烯醚(PEO)一聚氧丙烯醚(PPO)一聚氧乙烯醚(PEO)共聚物为模板剂制备结构可控的SiO2中孔材料,通过BET、TG/DTA、FT-IR、29SiNMR等分析手段,考察了不同条件下溶胶一凝胶制备化学及其热处理对SiO2中孔材料结构性质的影响规律和内在本质.结果表明:通过调节聚合度和添加量以及溶胶老化时间,可以对SiO2中孔材料织构性质进行有效的调控;同时由于该共聚物在不同气氛温度下的脱除机理不同,从而对材料的结构性质影响也有所不同;经真空热处理后,SiO2中孔材料柔性骨架得到加强,孔分布更趋集中.
The mesoporous SiO_2 xerogels with controlled texture were obtained using TEOS asprecursor in the presence of Polyethylene Oxide (PEO)-Polypropylene Oxide (PPO)-PolyethyleneOxide (PEO) by sol-gel method. By means of BET, TG/DTA, FT-IR and 29Si NMR analysis,the sol-gel chemistry was investigated and the effects of heat treatment in different conditions werealso discussed. The results show that the triblock copolymer molecular chain, additive amountand ageing time of SiO2 sol can adjust available the texture properties of mesoporous SiO2, and indifferent atmospheres, the removed mechanism of such copolymer is different, which results in thedifferent effects on the mesoporous SiO2. As a result, the mesoporous SiO2 has stronger flexibleskeleton, narrower pore distibution, and higher thermal stability by vacuum heat-treatment.
出处
《无机材料学报》
SCIE
EI
CAS
CSCD
北大核心
2000年第1期38-44,共7页
Journal of Inorganic Materials
基金
国家杰出青年科学基金!29625307