impingement, [ 11 ] tape-peeling, [ 11b ] waterimpact tests, [ 12 ] supersonic treatments, [ 12a ] or slight friction (a few centimeters or dozens of centimeters of abrasion with sandpaper). [ 13 ] Moreover, a host of current procedures either require complex processing and specialized equipment or are diffi cult to realize industrial-scale applications. [ 8b , 14 ] Clearly, the creation of a simple, low-cost superhydrophobic surface with excellent mechanical durability and practical utility for large-scale applications is urgently required. Recently, Lu et al. have developed a method to bond the self-cleaning coatings to the substrates by using adhesives; the resulting surfaces maintained their hydrophobicity after various types of destructive tests, including fi nger-wipe, knife-scratch, and 40 abrasion cycles with sandpaper tests. [ 15 ] However, such a two-layer system is unfavorable for paint construction.In the present work, we developed a polymer-based superhydrophobic composite coating by combining a methyl silicone resin with a superhydrophobic silica sol. To fabricate the superhydrophobic silica sol, we selected γ-aminopropyltriethoxysilane (APTES) and 1H,1H,2H,2H-perfl uorooctyltriethoxysilane (PFOTS) as the agglomeration agent and hydrophobic agent, respectively, with which to modify silica nanoparticles; the average diameter of this silica nanoparticles was about approximately 3-5 nm, which are smaller than other superhydrophobic nanoparticles reported in the literature to date. [ 15,16 ] We subsequently added a commercial methyl silicone resin to the superhydrophobic sol to enhance its mechanical durability. The coating exhibits remarkable superhydrophobicity even after being subjected to a fi nger-wipe test, a knife-scratch test, or 50 abrasion cycles with sandpaper. The coating exhibits high rigidity (pencil hardness of 9H), good fl exibility (impact resistance of 1 m kg) and great adhesion (5B).The superhydrophobic surface is attributed to a combination of topographical microstructures and chemical compositions. [ 17 ] When a drop of water (5 µL) was placed on the composite coating substrate, a perfect spherical water droplet formed with a CA of 166° and a SA of 1° ( Figure 1 a). The CAs were 137° and 129° for diiodomethane and edible oil, respectively, showing the coating's good oleophobicity. And the apparent surface free energy is 1.14 mJ·m −2 according to the Owens-Wendt method. The surface topography of the composite coating was examined by scanning electron microscopy (SEM). Numerous aggregated silica nanoparticles and micropores were observed to be distributed on the coated substrate (Figure 1 b). These particles and micropores can trap a large fraction of air, which is essential for The practical applications of superhydrophobic self-cleaning surfaces have been hampered by poor mechanical durability. Here, a composite coating that possesses excellent superhydrophobicity and robust mechanical durability is fabricated, consisting of a methyl silicone resin and a superhydrophobic sil...

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Depolymerization of nylon 6 to produce ε-caprolactam using an environmentally friendly heteropoly acid catalyst was studied at temperatures between 553 and 603 K in water. The products of depolymerization were analyzed qualitatively and quantitatively by means of mass spectrometry and high-performance liquid chromatography. The results showed that the depolymerized product was mainly ε-caprolactam with a little 6-aminocaproic acid and oligomers. The phosphotungstic heteropoly acid used as a catalyst can improve the hydrolysis rate and yield of ε-caprolactam. The optimum hydrolysis conditions for ε-caprolactam yield were as follows: phosphotungstic heteropoly acid content, 3%; reaction temperature, 573 K; and reaction time, 85 min. Under these conditions, the yield of ε-caprolactam was 77.96%. In the temperature range 553-603 K, the activation energy of 3% phosphotungstic heteropoly acid-catalyzed depolymerization was evaluated as 77.38 kJ/mol, which is lower than the 86.64 kJ/mol value for no catalyst. ExperimentalThe hydrothermal vessel used had a volume of 18 ml and was heated in an electric salt bath of 1:1 (Wt/Wt) NaNO 3 J Mater Cycles Waste Manag (2010) 12:321-325

Silicone/titania hybrids for LED encapsulation were synthesized via hydrolysis and condensation reaction between tetrabutyl titanate and silica sol containing phenyl groups and long alkyl chains. Crack-free thick films ($1 mm) were fabricated by curtain painting. The hybrid films with different Ti contents were characterized by FTIR, UV-VIS, TGA/ DSC, AFM, TEM, ellipsometer, etc. Results show that the hybrid films contain long alkyl chains which have high thermal stability against yellowing owing to the steric hindrance given by long alkyl chains. The hybrid films have high transmittance ( ‡98% in visible range) and high refractive index (1.591-1.681). In LED encapsulation, the silicone/titania hybrids with an RI of 1.605 increased the light extraction efficiency of bare blue LEDs by 19.4%.

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