Water resistance of coatings using

ASTM D1735 Testing the water resistance of coatings using water-fog apparatus (practice). 

D870—09 Standard Practice for Testing Water Resistance of Coatings Using Water Immersion... 

Standard Practice for Testing Water Resistance of Coatings Using Controlled Condensation Standard Practice for Atmospheric Environmental Exposure Testing of Nonmetallic Materials Standard Practice for Recording Data from Atmospheric Corrosion Tests of Metallic-Coated Steel Specimens... 

D 1735 Practice for testing water resistance of coatings using woter for opparatus... 

Amino resins are used by the paper industry in large volume for a variety of apphcations. The resins are divided into two classes according to the mode of appHcation. Resins added to the fiber slurry before the sheet is formed are called wet-end additives and are used to improve wet and dry strength and stiffness. Resins appHed to the surface of formed paper or board, almost invariably together with other additives, are used to improve the water resistance of coatings, the sag resistance in ceiling tiles, and the scuff resistance in cartons and labels. 

ASTM D 2247, Standard Practice for Testing Water Resistance of Coatings in 100% Relative Humidity, was originally pubhshed in 1966. As the title implies, it is primarily used to test the water resistance of coated specimens. The apparatus as depicted in D 2247 is shown in Fig. 2. 

F.M. Gel fand V.S. Alipchenko, Ibid 1967, (63/20), 209-12 CA 69, 11865m (1968) [Reasons for a fail are and break in detonations in flooded coal mines were investigated, Expis Ammonit PZhV-20 and Uglenit E-6, coated with water-resistant material, were used in testing. (Compns are not given in CA). It was decided that the excess pressure of CH4 in flooded coal faces was the cause of failure and break of detonation]... 

Oligophenylethoxysiloxanes are used as modifiers for various polymers to improve their weather resistance and other technical characteristics, as well as to increase the heat resistance of coatings. E.g., PES-50 is used to modify polyethers, aciylic and epoxy polymers PES-80 is used to modify alkyd and urea-formaldehyde resins. Besides, PES-80 is used as an additive in paints and enamels (to improve their flow properties, gloss and colour), as well as in concrete mixes (to improve the water resistance and durability of concrete works). 

Vinyl lacquers are used mainly where a high degree of chemical resistance is required these lacquers are based on vinyl chlorides and vinyl acetates. Acrylic lacquers are based on methyl methacrylate and methyl acrylate polymers and copolymers. Other esters of acrylic and methacrylic acid also may be used to make nonconvertible film formers. Judicious selection of these acrylic acid or methacrylic acid esters allows one to produce film formers with specifically designed properties such as hardness, flexibility, gloss, durability, heat, and chemical resistance. Acrylic lacquers, however, are not noted for their water resistance. The principal uses of acrylic-type lacquers are fluorescent and metallic paints, car refinish applications, clear lacquers and sealers for metals, and protective coatings for aircraft components and for vacuum-deposited metals, as well as uses in pigmented coatings for cabinets and appliances. 

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