Abrasion-resistant coatings for

Paints and Coatings. Ethoxysilanes are used in high temperature, zinc-rich paints (see Paint) (51,52). Methyl- and phenyltrialkoxysilanes are used to prepare abrasion-resistant coatings for plastics (53), particularly polycarbonate (54,55), and dielectric coatings and seals for high voltage electrical components, including television tubes. 

Polysiloxane-Silica Hybrid Resins as Abrasion-Resistant Coatings for Plastic Substrates... 

The development of urethane elastomers has allowed the formulation of tough, abrasion-resistant coatings for many flexible substrates including textiles. One widely used application of CAB-modified urethane elastomeric systems is for coating lightweight outdoor backpacking and camping equipment (e.g., portable tents). 

Diamond is the hardest naturally occurring material. Industrial diamonds are used as abrasives for grinding and polishing diamonds. Diamond and diamond-like coatings prepared using chemical vapor deposition processes are used to make abrasion-resistant coatings for many different applications (e.g., cutting tools). They are, of course, also used in jewelry. 

A wide range of polyurethane-type products has become available in recent years for coating applications. These include simple solutions of linear polyurethanes, two-pot alkyd-isocyanate and polyether-isocyanate systems and a variety of prepolymer and adduct systems. The coatings can vary considerably in hardness and flexibility and find use mainly because of their toughness, abrasion resistance and flexibility. Uses include metal finishes in chemical plant, wood finishes for boats and sports equipment, finishes for rubber goods and rain-erosion-resistant coatings for aircraft. One type of coating is potentially competitive with PVC leathercloth. Both alkyd-di-isocyanate and adduct-diisocyanate compositions may be coated on to fabrics from solutions of controlled viscosity and solids content. Such coated fabrics are soft, flexible and, unlike PVC leathercloth, free from plasticisers. 

Epoxy resin paints, inferior to chlorinated rubber for resistance to strong acids, are excellent for dilute acids and strong alkalis. They produce a harder, more abrasion-resistant coating than does chlorinated rubber and are much better for resistance to fats, oils and many organic solvents. Table 3.50 gives data on the chemical resistance of epoxy resin coatings to different materials. 

The ability of organically modified ceramics based on alumina, zirconia, titania, or silica (and mixtures of each) to function as abrasion-resistant coatings has also been studied (62). For example, polycarbonate, when coated with an epoxy—aluminosilicate system, experiences a significant reduction in the degree of hazing induced by an abrader, as compared to uncoated polycarbonate. 

Thin metalhc fihns play an important role in diverse fields of applications, with special emphasis on micro- and nanoelectronics for which the metals Al, Cu, Ag, Au, Ti and W are essential Additional fields of commercial interests are electrodes as well as reflective, corrosion-resistant, oxidation-resistant and abrasion-resistant coatings . Noble metals (periods 5 and 6 of groups 8-11 of the periodic table of the elements) are of special interest due to their manifold application in heterogeneous catalysis. Other metals used in specialized industrial applications or as components of more complex materials such as metal alloys are Ni, Pd, Pt, Ag and Au. For example, FePt-based nanostructured materials are excellent candidates for future high-density magnetic recording media . ... 

The attachment of cymantrene groups to polymers has attracted interest for other reasons. Studies have shown, for example, that adherent, abrasion-resistant coatings are formed on metals when thin films of the Mn-containing polymer are subjected to irradiation with UV light. The polymerization of styrene tricarbonylchromium 47 has also been studied.This species is available from the reaction of styrene with Cr(CO)3(NH3)3. Although the Cr monomer 47 resisted attempts at homopolymerization, co-polymerizations with styrene, methyl acrylate, as well as with 41 to yield bimetallic polymers 48 were possible (Equation (17)). In addition, co-polymerization with vinyl-ferrocene afforded co-polymers of low molecular weight (Mn = ca. 4,000). A variety of other organometallic vinyl momomers 49 has been successfully polymerized to yield polymers 50 that contain pendant Gr, W, and Ir carbonyl moieties (Equation (18)). ... 

For example, the abrasion-resistant coatings based on a silicone-silica hybrid (33) have provided a scratch- and mar-resistant finish for polycarbonate as well as metals. The chemistry involved is discussed by Vincent, Kimball and Boundy (3iL). The coating consists of polysiloxane and silane-modified submicron silica particles, microscopically dispersed in the solution. The coating is then cured at elevated temperatures. Currently, this type of abrasion resistant coating is marketed in the U.S. by Dow Corning and General Electric Company. 

Haluska, L. A. Wear Testing of Abrasion - Resistant Coated Plastics, Special Technical Publication 769, American Society for Testing and Material, (1982). 

Polyurethane coatings are used wherever applications require toughness, abrasion resistance, skin flexibility, fast curing, good adhesion, and chemical resistance. Use include metal finishes in chemical plants, wood finishes for boats and sports equipment, finishes for rubber goods, and rainerosion resistant coatings for aircraft. 

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