Aqueous-silicone coated

Figure 5. N(ls) high resolution spectra of polished silicon coated with y-APS from a 1% aqueous solution at pH 10.4. The take-off angles were (A)—15° and (B)—75°.

Figure 29.2 Schematic representation of an aqueous LBL coating layer on the phase separated silicone hydrogels surface in wet and dry conditions.

Qin et al. (2003) used SLMs for the separation of acetic acid and butyric acid from their aqueous solution. Polypropylene hfs and silicon-coated, microporous hydrophobic polypropylene membranes were used as support. In another study, Qin et al. (2002) demonstrated PV by using a liquid membrane consisting of nonvolatile hydrocarbons immobilized in the micropores of hydrophobic hfs on the outer surface of the fibers. TCE was separated and concentrated from its aqueous solution at 25°C and essentially atmospheric pressure. The feed TCE concentration was varied between 50 and 950 ppm the permeate pressure range was 0.6-70 mmHg. A 78-flber, 30-33 cm long module could achieve as much as 98% removal of TCE. It was reported by them that the hexadecane SLM was permselective for TCE the experimental selectivity was 30,000 and the intrinsic selectivity could be as high as 2 x 10 much higher than the values obtained by any solid membranes. 

Preparation by demethylation of 2 -[ T] fluoro-3,4-di-methoxy-5-nitrobenzophenone (SM) in dimethyl sulfoxide with aqueous hydrobromic acid first at r.t. and at 140° for 30 min. SM was obtained by action of [ T] cesium fluoride with 3,4-dimethoxy-2, 5-dinitro-benzophenone in dimethyl sulfoxide for 10 min at 150° in a silicone-coated tube (Vacutainer). 

Several approaches have been disclosed to make release coatings that can be printed with ink jet or laser jet printers (e.g., to make linerless labels). For example, Khatib and Langan [164] disclose a blend of two different acrylate functional silicones, one with a high level of acrylate functionality to provide the printability and one with a low level of acrylate functionality to provide easy PSA release. Lievre and Mirou [165] describe an aqueous blend of a crosslinkable silicone and poly(vinyl alcohol-vinyl acetate) resins while Shipston and Rice describe a blend of acrylic resin and a surfactant [166]. 

The resist formulation was spin-coated onto a silicone wafer on which a bottom antireflective coating had been previously applied and then soft-baked for 60 seconds at 90°C on a hot plate to obtain a film thickness of 1000 nm. The resist film was then exposed to i-line radiation of 365 nm through a narrowband interference filter using a high-pressure mercury lamp and a mask aligner. Experimental samples were then baked for 60 seconds at 90°C on a hot plate and developed. The dose to clear, E0, which is the dose just sufficient to completely remove the resist film after 60 seconds immersion development in 2.38% aqueous tetramethyl ammonium hydroxide, was then determined from the measured contrast curve. Testing results are provided in Table 1. 

Materials that form a permeable membrane include fats, bee wax, carnauba wax, cetyl alcohol, cetylsteryl alcohol, zein, acrylic esters, silicone elastomers, and ethylcellulose (14). Aqueous dispersions of water-insoluble polymers are commonly used for sustained-release film coatings. Examples of commercially available aqueous polymer dispersions include Surelease-containing ethylcellulose, Aquacoat-containing... 

The formulated resist composition is then spin coated on silicon wafers. The resist coating layer is exposed through a photomask at 193 nm, and then the exposed coating layers are post-exposure baked at 110°C. The coated wafers are then treated with a diluted aqueous tetramethylammonium hydroxide solution to develop the imaged resist layer and provide a relief image (61). 

Precipitation of the coating from aqueous solutions onto the suspended Ti02 particles. Batch processes in stirred tanks are preferred various compounds are deposited one after the other under optimum conditions. There is a very extensive patent literature on this subject. Continuous precipitation is sometimes used in mixing lines or cascades of stirred tanks. Coatings of widely differing compounds are produced in a variety of sequences. The most common are oxides, oxide hydrates, silicates, and/or phosphates of titanium, zirconium, silicon, and aluminum. For special applications, boron, tin, zinc, cerium, manganese, antimony, or vanadium compounds can be used [2.40], [2.41],... 

In general, polycarbonate resins have fair chemical resistance to aqueous solutions of acids or bases, as well as to fats and oils. Chemical attack by amines or ammonium hydroxide occurs, however, and aliphatic and aromatic hydrocarbons promote crazing of stressed molded samples. For these reasons, care must be exercised in the choice of solvents for painting and coating operations. For sheet applications, polycarbonate is commonly coated with a silicone—silicate hardcoat which provides abrasion resistance as well as increased solvent resistance. Coated films are also available. 

Coil coaters operate equipment continuously and, in most cases, operate catalytic fume abaters 6000—7000 h/yr. Under these conditions the anticipated catalyst life is years, with an annual aqueous solution cleaning. However, the catalyst may last no more than two years if frequent maintenance is needed, such as in-place air lancing every 60 to 90 days to remove noncombustible particulates. Frequent maintenance may be needed if coatings such as siliconized polyester (15—40% silicones) comprise 30% of the coatings put through the system. 

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