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Films of°-aminopropyltriethoxysil ane (°-APS), 1,2-bis[triethoxysilyl ] ethane (BTSE) and their mixtures adsorbed onto pure aluminum from aqueous solutions were characterized by means of ellipsometry, infrared spectroscopy (IR) and X-ray photoelectronspectroscopy (XPS). It was found that after hydrolysis in water the silanes were readily adsorbed onto aluminum oxide surfaces initially forming hydrogen bonds. Upon curing, such bonds are replaced by metallosiloxane bonds, Si O Al. The remaining silanol groups in the lm condense and form Si O Si bonds. As the Si O Al bonds are known to hydrolyze, the corrosion protection is related to the hydrophobicity of the siloxane lms formed on the metal substrate. BTSE lms are acidic as they contain free silanol groups, therefore these are compatible with some paints but not with others. Electrochemical impedance spectroscopy (EIS) results, salt spray test results and liform corrosion test results showed that some silane treatments, such as two-step°-APS /BTSE and BTSE only, provided better corrosion protection on aluminum substrates as compared with a chromate treatment. Mechanisms of adhesion and corrosion protection of these silane lms on aluminum substrates are proposed.

With multi-wall carbon nanotubes (MWNTs) as reinforcement, a 12 vol% MWNTs/alumina (Al 2 O 3 ) ceramic composite was obtained by hot pressing. A fracture toughness of 5.5570.26 MPa . m 1/2 , 1.8 times that of pure Al 2 O 3 ceramics, was achieved. Experimental results showed that the enveloping of carbon nanotubes (CNTs) with sodium dodecyl sulfate (SDS) is effective in changing the hydrophobicity of CNTs to hydrophilicity and improving the dispersion of CNTs in aqueous solution. Enveloped with SDS, CNTs can be homogeneously mixed with Al 2 O 3 at a microscopic level by heterocoagulation. This mixing method can obviously improve the chemical compatibility between CNTs and Al 2 O 3 , which is important for enhancement of interfacial strength between them. J ournal

Bio-filled polymer composites are gradually replacing plastics to achieve the aim of environmental sustainability. Present study has been carried out to prepare the composites made by reinforcing waste peanut shell powder (PSP) as a natural filler into epoxy resin matrix. The natural filler extracted by manual process was subjected to alkali treatment with the concentrations of 2, 5 and 7 w/v%. The composites fabricated by varying the weight fractions of filler in the range of 5 to 15 wt%. The effects of bio-filler content of the composites on tensile and thermal properties were evaluated by Fourier transmission infrared spectroscopy (FTIR), universal testing machine, scanning electron microscope (SEM) and thermal gravimetric analysis (TGA). The studies reveal that the tensile strength and tensile modulus increased with the increasing of bio-filler content. The highest mechanical properties of 7 % alkali treated PSP loaded Epoxy composite were achieved at biofiller mass content of 15 wt.%. The morphology of the composites shows better bonding between the filler and resin, thus leading to improvement of the mechanical properties. The TGA results revealed that the polymer composites showed thermal resistance on increasing NaOH concentration and filler content.

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