N-Butyl amine has been grafted unto Dow epoxy resin. The product was evaluated as an acid inhibitor by gravimetric techniques. The reduction in corrosion of aluminium in 1？M HCl solution was 92% at and 83% at with an inhibitor concentration of 100？ppm. The corrosion rate at this concentration was and mm/yr at and . For the specimens in HCl without inhibitor at 10-hour immersion period, the corrosion rate was and mm/yr, respectively, at and . Data obtained correlate with Langmuir isotherm. 1. Introduction Aluminium and its alloys find extensive application in the construction of heat exchangers, radiators, and related components in water cooling/treatment facilities. It is often observed that such facilities may suffer corrosion damage from ingress of chlorides and other extraneous anions as a result of inadequate provision for corrosion mitigation such as faulty design features and nonintroduction of suitable corrosion inhibitors into the system. Pitting corrosion at crevices and under sediments is often encountered in such industrial situations. The use of organic inhibitors is the most economical and practical method of protecting metals against aqueous corrosion [1–3]. These inhibitors contain heteroatoms such as Sulphur, Oxygen, and Nitrogen in their structures in addition to multiple bonds and may contain cyclic hydrocarbons as well [3–6]. The mechanism of inhibition of these organic compounds is thought to be by adsorption which may depend on the number of heteroatoms and the surface area of the corroding metal/alloy [7, 8]. Various investigators [8–13] have researched on polymers as corrosion inhibitors because of their large surface areas, cost effectiveness, and inherent stability. These polymers have been reported to be very efficient at low concentrations in very aggressive media although efficiencies vary widely as a result of differences in composition. Chemically modified polyurethane [14] gave about 95% inhibition efficiency for mild steel corroding in acidic medium. On the other hand, polyacrylamide [15] achieved an efficiency of about 63% for aluminium corroding freely in 0.5？M HCl solution. In order to contribute towards the search for suitable corrosion inhibitors of polymeric origin, in the present investigation, a Dow epoxy resin was chemically modified with n-butyl amine at suitable temperatures and examined as corrosion inhibitor for aluminium in 1？M HCl solution. 2. Experimental 2.1. Materials 99.99% aluminium with nominal impurities of 0.004？wt% Fe, 0.002？wt% Cu, and 0.003？wt% Si was made into electrodes measuring 10？mm × 10？mm
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