SYNTHESIS OF MESOPOROUS POLY(STYRENE-co-MALEIC ANHYDRIDE)/SILICA HYBRID MATERIALS VIA A NONSURFACTANT-TEMPLATED SOL-GEL PROCESS

Mesoporous poly(styrene-co-maleic anhydride)/silica hybrid materials have been prepared. The synthesis was achieved by the HCl-catalyzed sol-gel reactions of tetraethyl orthosilicate (TEOS) and styrene-maleic anhydride copolymer in the presence of 3-aminopropyl triethoxysilane (APTES) as a coupling agent and citric acid as a nonsurfactant template or pore-forming agent, followed by ethanol extraction. Characterization results from nitrogen sorption isotherms and powder X-ray diffraction indicate that polymer-modified mesoporous materials with large specific surface areas (e.g. 900 m(2)/g) and pore volumes (e.g. 0.6 cm(3)/g) could be prepared. As the citric acid concentration is increased, the specific surface areas, pore volumes and pore diameters of the hybrid materials increase.

Effects of Template Contents on the Physicochemical Sorption Properties of Zr-Incorporated Mesoporous Titania Materials

Zr-Incorporated mesoporous titania materials were prepared via nonsurfactant templated sol-gel process of zirconium (IV) butoxide (ZBT) and titanium (IV) butoxide (TBT) in the presence of urea molecules as template or pore forming agent. The effects of template contents on the pore parameters of the materials synthesized with fixed Zr incorporation contents were investigated by nitrogen adsorption-desorption measurements, powder X-ray diffraction (XRD) study and transmission electron microscopy (TEM). The changes of template contents play significant roles on the pore parameters at low incorporation content of Zr. The pore diameters display a clear increase tendency with the increase of template contents. When high Zr incorporation content is used, the template contents have less effect on the pore diameters that almost keep unchanged with the increase of template contents. All the materials possess type IV isotherms with H 2 hysteresis loops suggesting the formation of mesophase. The materials with low Zr incorporation content have anatase structures; however, it can not be found in the materials with high Zr incorporation content. TEM images show that some accumulated inter-particulate pores and well-distributed worm-like pores are present in the Zr-incorporated materials.

Synthesis of mesoporous silica materials with ascorbic acid as template via sol-gel process

Mesoporous silica materials with pore diameters of 2–5 nm have been prepared using ascorbic add as a nonsurfactant template or pore-forming agent in HCl-catalyzed sol-gel reactions of tetraethylorthosilicate, followed by removing the ascorbic acid compound by extraction with ethanol. Characterization results from nitrogen sorption isotherm, powder X-ray diffraction and transmission electron microscopy indicate that me materials have large specific surface areas (e.g. 1000 m2/g) and pore volumes (e.g. 0.8 cm3/g). The mesoporosity is arisen from interconnecting disordered wormlike channels and pores with relatively broad size distributions. As the ascorbic acid concentration is increased, the pore diameters and pore volumes of the materials increase.