Steel adhesion, improving durability

Primer 2000 (b) Thermosetting acrylic adhesives 5—10 pm Air drying in 3-5 min at room temperature Cleans and etches aluminum and stainless steel Provides improved durability to salt water... 

Aluminum powder, in particular, is frequently employed at relatively high concentrations in high-temperature epoxy adhesive formulations. The filler provides improvement in both tensile strength and heat resistance, and it increases the thermal conductivity of the adhesive. Aluminum powder fillers also reduce undercut corrosion and, hence, improve adhesion and durability of epoxy adhesive between bare steel substrates. It is believed that this is accomplished by the aluminum filler providing a sacrificial electrochemical mechanism.27... 

De Nicola, A. J., and Bell, J. P., Synthesis and Testing of p-Diketone Coupling Agents for Improved Durability of Epoxy Adhesion to Steel, in Adhesion Aspects of Polymeric Coatings, K. L. Mittal, ed., Plenum Press, New York, 1983, p. 443. 

Polyfunctional Chelating Agents for Improved Durability of Epoxy Adhesion to Steel... 

Chelating Agents for Improved Durability of Epoxy Adhesion to Steel," Org. Coatings and Appl. Polym. Sci. Proceedings, 489 (1982). 

Aluminum powder is often included to modify the thermal conductivity of epoxies. It also reduces undercut corrosion and hence improved adhesion and durability of epoxy adhesives between bare steel substrates, perhaps by a sacrificial electrochemical mechanism. 

In reinforcing materials double-dipped polyesters for improved tire durability, plasma-treated yams for improved bonding in tire, and increased usage of aramid fabric as belt and application of PEN are the areas where manufacturers are showing interest. Introduction of new styles of steel wire geometry for improved mbber to metal adhesion and new steel wire coating formulations for improved mbber to metal bonding are other focused areas of development. 

Abstract—The effects of metal alkoxide type and relative humidity on the durability of alkoxide-primed, adhesively bonded steel wedge crack specimens have been determined. Aluminum tri-sec-butoxide, aluminum tri-tert-butoxide, tetrabutyl orthosilicate, and titanium(IV) butoxide were used as alkoxide primers. Grit-blasted, acetone-rinsed mild steel adherends were the substrates bonded with epoxy and polyethersulfone. The two aluminum alkoxides significantly enhanced the durability of the adhesively bonded steel, while the titanium alkoxide showed no improvement in durability over a nonprimed control. The silicon alkoxide-primed samples gave an intermediate response. The failure plane in the adhesively bonded samples varied with the relative humidity during the priming process. 

The test results show that the RPC possesses high bond strength, dynamic modulus, and bond durability as compared with other concretes. The adhesion between the RPC and the steel is also much greater than that for the other concretes. It would be interesting to verify the consequences of this improved adhesion in reinforced concrete structures. 

The business of paints and coatings is very competitive, and many chemical manufacturers specialize in compounds for this industry. The addition of a corrosion inhibitor is often only a minor factor in the overall success of the paint in protecting structural steel or iron. The adhesion of paint to metal is also quite important, as are factors that influence its ease of application and durability. Formu-lators, chemists whose job it is to devise improved mixtures of substances in products, spend millions of person-hours annually trying to devise improved paints to combat corrosion better. 

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