Epoxy polymer concrete corrosion resistance

RubCon can be used in specialized structures instead of traditional building materials (reinforced concrete, steel, wood). Comparison of technical and economic parameters of RubCon with the most widespread kinds of corrosion-resistant concretes, in particular polymer concrete based on epoxy and polyester resins, showed that the cost of a useful loading unit of the RubCon structure is more than twice as effective as epoxy polymer concrete and 2.2 times as effective as polyester polymer concrete. 

The same basic epoxy resin systems are used as monolithic surfacings and epoxy polymer concrete. In addition to these, epoxy phenol novolac is also used to produce mortars and grouts. This is a higher viscosity resin that requires the inclusion of various types of diluents and resin blends. Table 10.3 lists the atmospheric corrosion resistance of the mortars and grouts. 

PCs based on epoxy resin binder are resistant to many corrosive environments such as a concentrated solution of caustic soda at 90°C the action of alkali metal salts, alcohols, oils, gasoline and other aliphatic hydrocarbons. The flexural strength of epoxy PC is slightly affected by immersion in a 10% solutions of sulfuric acid and chloride sodium, which is an indicator of the good chemical resistance of this kind of concrete to these aggressive agents [11], However, these polymer concretes are not resistant to a sulfuric acid concentration of 60% and nitric acid concentrations above 70% [12],... 

The polymer-cement concrete reveal, apart from the higher compressive strength— better adhesion to aggregate and lower porosity of the interfacial transition zone in comparison with traditional concrete. The propa tion of cracks in concrete is thus changed [61,62]. The tightness of polymer-cement concrete and resistance to the attack of corrosive environment, including the acidic one, are generally improved. In the latter case the epoxy resin is reconunended. In the two papers by Czamecki (one with Lukowski) [5,61] the recent achievements in the area of polymer-cement concrete are presented. 

For overall corrosion resistance the epoxy novolacs are somewhat superior to bisphenol A. However, for strictly atmospheric corrosion resistance bisphenol A is satisfactory. The filler most often used with epoxy concretes is silica along with an amine hardening system. This combination provides a polymer concrete with outstanding physical properties and moderate overall corrosion resistance. However, it is perfectly suitable to resist normal atmospheric corrosion (see Table 10.2). 

Recent information suggests that such coatings operate by increasing the electrical resistance between the steel and the concrete both epoxy and polymer-cement-based materials seem to have this effect, reducing local corrosion current exchange [9]. 

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