Adhesion, of coatings

Heat treatment after plating Heat treatment may be necessary after plating to improve the adhesion of coatings on aluminium and its alloys when certain processes, e.g. the Vogt process, are used, or to minimise hydrogen embrittlement of steel parts. Care is needed since heating may distort the part and impair the mechanical properties of the substrate. 

Plastic pellets, threat from, 20 231 Plastic pumps, for corrosive liquids, 21 76 Plastic refractories, 21 482 Plastics. See also Styrene plastics adhesion of coatings to, 7 91-92 advanced materials, 1 693 cellulose ester applications, 5 404 chemical exposure tests on, 19 583 citric acid application, 6 648 colloidal suspensions, 7 273t colorants for, 7 358-380 development of, 10 168... 

Carboxylated Polyester Additives for Improving the Adhesion of Coatings... 

Carboxylated polyesters were prepared by extending hydroxyl-terminated polyester segments with dianhydrides. Carboxylated polyesters which were soluble in common lacquer solvents were effective in improving the adhesion of coatings on a variety of substrates when 1-10% was blended with cellulose acetate butyrate, poly(vinyl chloride), poly(methyl methacrylate), polystyrene, bisphenol polycarbonates, and other soluble polymers. 

Incorporation of carboxyl groups in vinyl polymers (J) and polyolefins (1, 7) improves the adhesion of these polymers to various materials. However, many of these carboxylated polymers, particularly the carboxylated polyolefins, have limited solubility in volatile, lacquer-type solvents such as butyl acetate or methyl ethyl ketone and thus are limited in their ability to improve the adhesion of coatings applied from solvents. Carboxylated polyesters that are soluble in these solvents can be prepared. We were therefore interested in determining the effects of structure and carboxyl content on the adhesion of coatings of various classes of polymers blended with carboxylated polyesters. 

Adhesion of Coatings. Except for K-l polycarbonate [4,4 -(2-nor-bornylidene)diphenol polycarbonate] (4), an experimental polymer (inherent viscosity 0.85), all the coatings were prepared with commercial products EAB-381-0.5 and EAB-381-20 cellulose acetate butyrates from Eastman Chemical Products, Inc. VYHH vinyl chloride (87%)/vinyl acetate (13%) copolymer from Union Carbide Corp. Butvar B76 poly-(vinyl butyral) from Shawinigan Resins Corp. Plexiglas V poly (methyl methacrylate) from Rohm and Haas Co. Dylene P3I polystyrene from... 

Adhesion of coating good very good excellent... 

Plastics for which the adhesion of coatings may be improved by plasma pre-treatment are reported to be polyethylene, polypropylene, polycarbonates, polyacetals, polyaromatic esters, polyimides, polyamides, polyphenylene ether, polyacrylates, acetal homopolymer, and poly(ether imide). 

Sometimes primers can take the place of surface treatments. Two examples are with porous substrates and with certain plastic substrates. With weak porous substrates, such as wood, cement, or porous stone, the primer can be formulated to penetrate and bind weakly adhering material to provide a new, tightly anchored surface for the adhesive. Chlorinated polyolefin primers will increase the adhesion of coatings and adhesives to polypropylene and to thermoplastic olefins. The chlorine atoms in the outer surface of the primer increase surface energy and enhance adhesion of adhesives, sealants, and paints. 

Soluble in cold water, GI fluids, and polar solvents becomes tacky when dried, so is unsuitable for use alone, often used in combination with other polymers to optimize adhesion of coat Soluble in cold water, GI fluids, alcohols, and... 

It is generally accepted that coating endurance, especially in moist air, is very dependent on the strength of adhesion of coating to substrate. Fleischauer and Bauer ° came to the conclusion that, just as slight oxidation of the lower layers of... 

A useful side effect of the radiation and especially the plasma treatments is the cleaning of the fibre surface. Fibre lubricants, sizing agents, soil and other residuals are burned off This provides, combined with the creation of reactive radicals on the fibre surface, better wetting properties and a higher adhesion of coatings and laminations. Anti-felting finishes for wool are also achievable with plasma treatments. 

A luminous chemical vapor deposition (LCVD) layer could be used as transition phase between metal and polymer (coatings or films). The deposition of LCVD layer on metals can be done by the cathodic LCVD, in which the metal to be incorporated is used as the cathode of DC discharge. This method provides an excellent adhesion of LCVD nanofilm to the metal as well as the adhesion of coatings that will be applied on the surface of the LCVD layer [1,2]. This method is described in some detail in Part IV. 

The variables likely to affect the process of adhesion of coated tablets to mucosal surfaces are shown in diagrammatic form in Fig. 12.15 film coat thickness, the nature of the film coat, its rate of solution or hydration, the rheology of the solution formed, its surface tension and its elongational characteristics. Eight stages have been identified. Stage 1... 

Plasma polymerization coating is a unique nanofilm coating technology that yields a tight amorphous network structure of atoms contained in the monomer (Type A plasma polymers). Because of the unique growth mechanism of plasma polymerization, excellent adhesion of coating could be obtained in a practical manner. 

Testing procedure In general, standard methods were used, with some improvements to obtain better resolution. A photoacoustic detector was used to obtain spectra of fumed silica. A carbon black background was used. In studies of adhesion of coatings on metal substrates, a gold coated background was used as the reference. 4 Diffuse respectra, and kaolin. 2 A... 

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