The mesoporous silica have been considered fascinating materials for many techonological applications due to their porous and morphological characteristics. This review focuses on their use as stationary phases for liquid chromatography, supports for immobilizing biomolecules, catalysts, agent for polymer reinforcement and hard templates for the preparation of mesoporous carbons.

Poly(lactic acid) (PLA) and starch copolymers are obtained by reactive blending -varying the starch compositions from 0 to 60%. PLA is functionalized with maleic anhydride (MA), obtaining PLA-g-MA copolymers using dicumyl peroxide as an initiator of grafting in order to improve the compatibility and interfacial adhesion between the constituents. PLA þ starch blends without a compatibilizer do not have sufficient interfacial adhesion. Decomposition temperature of PLA is not affected by grafting. Glass transition temperatures and dynamic mechanical properties are affected since MA has a plasticizing effect. Along with an increasing starch content friction decreases while wear loss volume in pin-on-disk tribometry has a minimum at nominal 15% wt. starch but increases at higher starch concentrations. The residual depth in scratching and sliding wear testing has a maximum at 15% starch; there is a minimum of storage modulus E 0 determined in dynamic mechanical testing at the same concentration. Microhardness results also reflect the plasticization by MA.

The present article describes preparation, characterization, and physical properties of nanoparticles-filled composites consisting of multiwall carbon nanotubes (MWCNT) and styrene-butadiene rubber and nitrilebutadiene rubber. The reinforcing MWCNT fillers were synthesized by chemical vapor deposition on iron and cobalt catalysts supported by calcium carbonate substrates. These MWCNT were further treated with nitric acid to produce hydroxyl and carbonyl functional groups on the carbon nanotubes (CNT) surfaces. Of particular importance is that these functionalized CNTs were found to exert profound influence on the elastomeric matrices, particularly the vulcanization activation energy, resistance to solvent swelling, enhanced glass transition temperature, and improved storage and loss moduli.

The number and nature of silanol groups could be estimated in mesoporous silica prepared with cetyltrimethylammonium bromide (CTMBr) in acidic medium to obtain a material appropriate as a stationary chromatographic phase, using thermogravimetric analysis (TGA) and diffuse reflectance infrared spectroscopy (DRIFT). The temperature-programmed desorption of pyridine in the DRIFT cell was quantitatively correlated to the change in intensity of the two IR bands, 1595 and 1446 cm -1 , assigned to pyridine interacting respectively with hydrogen-bonded and free silanol groups, after the determination of the absorptivities for the two bands. For calcined or solvent extracted samples, the silanol density (3-4 groups/nm 2 ), is represented mainly by hydrogen-bonded silanol groups. A significant increase is obtained by rehydroxylation. Activation by heating above 200 °C promotes the condensation of the vicinal silanol groups.

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