Priming metals

Jones, F.R., Interfacial aspects of glass fibre reinforced plastics. In Jones, F.R. (Ed.), Interfacial Phenomena in Composite Materials. Butterworths, London, 1989, pp. 25-32. Chaudhury, M.K., Gentle, T.M. and Plueddemann, E., Adhesion mechanism of poly(vinyl chloride) to silane primed metal surfaces. J. Adhes. Sci. Technol, 1(1), 29-38 (1987). Gellman, A.J., Naasz, B.M., Schmidt, R.G., Chaudhury, M.K, and Gentle, T.M., Secondary neutral mass spectrometry studies of germanium-silane coupling agent-polymer interphases. J. Adhes. Sci. Technol., 4(7), 597-601 (1990). 

This procedure identifies plastisols that are spread-coated on different substrates such as paper, aluminum foil, wood, and plastic sheet or film. Application is by doctor blade, direct roll, or reverse roll operations (Chapter 10). As an example plastisols are roll coated on adhesively primed metal for house sidings, conveyor belts, cloth fabrics, wood panels, and so on. 

With the flexibility of the blown film extrusion process, one-step production of wide multilayer films is possible. Incorporating a built-in adhesive layer, PVDF films can be laminated directly onto various thermo and thermoset plastics or primed metal substrates. PVDF films can protect the esthetics of UV sensitive substrates while also providing a thermal, chemical, and abrasion-resistant barrier. Recently, white PVDF films have been commercialized that are of full opacity in the UV range of 290 00 Most recently,... 

Boron is the prime metal in the area of stoichiometric interactions between metals and unsaturated bonds. Especially, boron hydride additions have been investigated, in particular by H. C. Brown and his students. Nowadays, these addition reactions are well-established text book subjects. A number of reviews on hydroboration have appeared . The development of a clear mechanistic picture lagged far behind the applications in synthesis. It was also the group of Brown that contributed to mechanistic understanding by performing careful kinetic measurements using 9-borabicyclo[3.3.1]nonane, abbreviated as 9-BBN-H, as reagent. Reactive alkynes such as 1-hexyne and 3-methyl-1-butyne exhibited first-order kinetics in 9-BBN-H with a rate constant equal to that of reactive... 

Most lead concentrates contain a portion of zinc and vice versa, so that both metals are impurities from the viewpoint of the prime metal contained in the concentrates. Therefore, each smelting activity inevitably produces disposal materials containing the other metal. Korea Zinc has been committed to maximize metal recoveries in lead and zinc production and to reject all non-valuable materials in the concentrate feed in a stable form such as slag. In this respect, Korea Zinc has developed a concept integrating lead and zinc production plants as shown in Figure 1. 

Reinhart, T.J. In Allen, K.W. (Ed.), Adhesion 2, Novel Concepts for Priming Metallic Adherends for Structural Adhesive Bonding. Applied Science Publishers, Barking, 1987, p. 87. 

Once cleaned, the metal surfaces are coated with a primer prepared by rollmilling 200 g of adhesive composition and 5(X) g of methanol. A first layer of primer is appUed to the metal parts, dried for 10 min at 90°C, covered with a second layer of primer and finally dried at 90°C for 1 h in an air circulating oven. The adhesive film is inserted between the two primed metal surfaces and the assembly is placed between the platens of a hydraulic press preheated to 316°C. A pressure of 0.3-0.5 MPa is applied and the test specimens are cured at 316°C for 1.5 h, before cooling down to 100°C under pressure. The assemblies are removed from the press and postcured in an air circulating oven as follows the temperature is raised from 20 to 300°C in 1 h, then from 300 to 350°C in 5 h and left at 350°C for 5 h. The lap shear strength values determined at different temperatures are plotted in Fig. 29 for TU-2 Ti/li assemblies [curve (a)] and ZIO CNT 1810 stainless steel coupons [curve (b)]. 

Photo-cure 2 Printing inks, wood coatings, paper and board varnish, coatings for plastics and primed metals... 

D 2246 Test method for testing finishes of primed metallic substrates for humidity-thermal cycle... 

Resorcinol and phenol resorcinol. Resorcinol adhesives are primarily used for bonding wood, plastic skins to wood cores, and primed metal to wood. Adhesive bonds as strong as wood itself are obtainable. Resorcinol adhesives are resistant to boiling water, oil, many solvents, and mold growth. Their service temperature ranges from —300 to 350°F. Because of high cost, resorcinol resins are often modified by the addition of phenolic resins to form phenol resorcinol. 

Manufacturers Comments Long open time, st cure. High initial strength. Good adhesion to PVC, fiBS. SMC and primed metals. 

The ability to clean and prime metals with environmentally-compliant and environmentally-friendly chemicals is being studied in all industries to maximise adhesive strength and enhance long-term durability. 

What is the workmen s (trade union s) attitude towards the working of prefabrication primed metals, especially welding ... 

What will be the effect of weathering (in stock and in work) on prefabrication primed metal and what precautions will be necessary prior to apphcation of further coatings ... 

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