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Rod-like and spherical mesoporous SBA-15 silica particles were synthesized as pure silicas and surface modified by organosilane coupling agents firstly, and then the effects of these mesoporous materials on the critical micelle concentration (CMC) of sodium dodecylsulfate (SDS), the stabilities of batch and semi-continuous MMA emulsion polymerizations, and the molecular weights and molecular weight distributions of the polymer products were studied. The incorporation of both unmodified and silane-modified forms of the mesoporous silica particles in the polymerization reaction increased the CMC of SDS. The presence of the unmodified mesoporous silica in the polymerization process led to instability in the batch emulsion polymerization process, as indicated by the formation of increased amounts of coagulum, and a decrease in the molecular weight of the polymer product. However, in comparison to the polymer formed in the absence of particle additives the molecular weight of the PMMA polymer increased with the amount of emulsifier and the addition of silane-modified SBA-15 particles, suggesting the growth of the polymer chains is facilitated at least in part by reaction in the pores of the particles. The improvement in molecular weight indicates that semi-continuous MMA emulsion polymerization is best suited for the preparation of PMMA-mesoporous silica composites., INTRODUCTION Since the discovery of hexagonally ordered mesoporous molecular sieves silicas at the beginning of the 1990s, the synthesis and application of the advanced mesoporous materials have undergone rapid growth. [...]

The proton transfer process mediated by water molecules adsorbed in an aluminosilicate framework was studied using ab initio molecular dynamics simulations. The investigation was conducted using a quasi-one-dimensional model simulating the mesoporous aluminosilicate channel structures.

A novel three-step assembly pathway is reported for the formation of a mesostructured alumina with framework pore walls made of crystalline, lathlike gamma-Al203 nanoparticles. The high surface areas (300-350 m2/g) and pore volumes (0.45-0.75 cm3/g) provided by these mesostructured forms of gamma-Al203 are useful in materials and catalytic applications where the availability of surface Lewis acid sites and the dispersion of supported metal centers govern reactivity.

A grafting process has been found to be effective in producing sieves that bind quantitatively more heavy metal ions than standard techniques. The sieves were made using covalent grafting of 3-mercaptopropylsilyl groups MCM-41 and HMS to the framework pore walls. The functionalized HMS derivative has found to bind more mercury (II) ions than the initially anionic MCM-41 derivative.

A novel assembly approach was used to prepare a porous lamellar silica with a hierarchical structure (MSU-V). This involved the cooperative formation of multilamellar vesicular surfactant-silica complexes, through the H-bondong interactions between H2N(CH2)12-NH2 as products of the tetraethylorthosilicate. Sorption properties of the lamellar MSU-V silica were similar to pillared lamellar clays.

The physical and catalytic properties of two titanium-substituted mesoporous catalysts prepared at ambient temperatures via electrostatic and neutral assembly pathways were compared. Specifically, Ti-MCM-41 and Ti-HMS molecular sieves were characterized with respect to their catalytic function in the liquid phase peroxide oxidations of methyl methacrylate, styrene, and 2,6-di-tert-butylphenol. The results demonstrated their superior catalytic efficiency over other titanium silicates.