![]() Li, Jing Xu, Lu Yang, Baixue Wang, Hongyu Bao, Zhihong Pan, Weisan Li, Sanming There was no further formation of gel due to low availability in the interaction between silicate anions and surfactant cations when the amount of TEOS was fixed for every synthesis cycle.įacile synthesis of functionalized ionic surfactant templated mesoporous silica for incorporation of poorly water-soluble drug. The concentration of the surfactant template has reached value lower than the critical micelle concentration (CMC) and remained constant after the 4th cycle. The surface area of the powder produced was found to be 1170, 916, 728, and 508 m2/g for 1st, 2nd, 3rd and 4th respectively. The result showed that 1.28, 0.37, 1.64, 1.90 and 0.037 g were obtained in the 1st, 2nd, 3rd, 4th and 5th synthesis cycle, respectively. The quality of the calcined MCM-41 powder produced in each synthesis cycle was evaluated by calculating the amount of MCM-41 produced and the surface area of the powder product. The synthesized gel was not produced in the unifying solution in the fifth cycle of MCM-41 synthesis. The synthesis procedure was repeated till no further solid product was formed. The as-synthesized MCM-41 powder is recovered by filtration while the filtrate (mother liquor) was then reused for the second synthesis cycle. The synthesized gel is formed thoroughly by mixing the two solutions under acid conditions with a pH value of 0.5 for 1 hour and kept for crystallization for 48 hours. In the synthesis of MCM-41, tetraethylorthosilicate (TEOS) solution in water was utilized as the silica source while hexadecyltrimethylammonium bromide (CTAB) solution in ethyl alcohol was used as a surfactant template. The recycling of surfactant template is investigated through the reuse of the surfactant template in the mesoporous MCM-41 synthesis process. Recycling of surfactant template in mesoporous MCM-41 synthesis The size of the smaller pores could be tuned from 2 to 6 nm by selecting different surfactants and by changing the concentration of reactants In contrast, the smaller mesopores formed by surfactant templates have a narrow distribution their size is about 3.9 nm. The larger channel pores formed by removing the microfibrils of uniaxially stretched polypropylene membrane have a broad pore size distribution, and their size is around 13 nm. Their regularity and morphologies were characterized by transmission electron microscopy (TEM), x-ray diffraction and Brunauer-Emmett-Teller (BET) surface area analysis. Hierarchically mesoporous silica materials with a bimodal distribution were template-prepared from uniaxially stretched polypropylene membrane in the presence of a surfactant via a sol-gel process. Wang Xiaocong Ma Jin Liu Jin Zhou Chen Zhao, Yan Yi Shouzhi Yang Zhenzhong International Nuclear Information System (INIS) Hierarchically mesoporous silica materials prepared from the uniaxially stretched polypropylene membrane and surfactant templates
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