Epoxy polymer concrete

Because they are relatively expensive, epoxy polymers have not been used very widely as binders in PC products. Therefore, epoxy PC is used for special applications, in situations in which the higher cost can easily be justified, such as mortar for industrial flooring to provide physical and chemical resistance, skid-resistant overlays (filled with sand, emery, pumice, quartz) in highways, epoxy plaster for exterior walls (e.g., in exposed aggregate panels), and resurfacing material for deteriorated areas (e.g., in flooring). Epoxy PC reinforced with glass, carbon, or boron fibers is used in the fabrication of translucent panels, boat hulls, and automobile bodies [2,6], 

Dilution of epoxy resins is achieved by introducing solvents. In this case, the viscosity is much reduced and the pot life is increased. However, the use of volatile solvents leads to formation of pores and capillaries in the binder, and hence to a reduction in polymer density [7], 

It was concluded that the amount of resin and filler in the chemical composition of the fabricated epoxy PCs had a great influence on identification of the maximum physical strength. The PC specimen with 15% resin and 200% filler resulted in maximum compressive and flexural strength. The tensile strength was maximized with 20% resin and 200% filler. The mechanical strength of fabricated PCs was 4- to 5-fold higher than Portland cement concrete [5], 

Carbamide (urea-formaldehyde) resin is prepared by the poly condensation reaction of urea and formaldehyde in aqueous or aqueous-alcoholic medium. 

Polymer concretes based on carbamide resins have a low toxicity and are favorable in manufacturing. However, the content of the polymer matrix in these PCs is high (up to 30%) and their physical and mechanical properties are low in comparison to other types of polymer concretes. 

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Epoxy seal coating was first applied as test patches in industrial plants in 1953. In 1957 epoxy polymer concrete was first used as a wearing course in the repair of popouts and spalled areas on the surfaces of various bridge decks in California (ACI, 1993). 

One can see that epoxy polymer concrete exhibits higher compressive strength, with values ranging from 3.8-4.3 times higher than commercial concrete. Compressive strength of this PC shows an increase of 1.5 times when glass fibers are added to the epoxy resin matrix and 2.0 times with the use of carbon fibers [8],... 

The ultimate compressive strength of drying epoxy polymer concrete samples is about 92% of the control sample strength, which testifies to a high degree of reversibility of the process associated with the adhesive nature of the interaction between binder and filler. 

Golestaneh, M., Amini, G., Najafpour, G. D., and Beygj M.A., Evaluation of Mechanical Strength of Epoxy Polymer Concrete with Silica Powder as Filler, World Applied Sciences Journal 9, no. 2 (2010) 216-220. 

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. 

RubCon at operation in aggressive environments is 2.2-32 times as economically efficient as epoxy 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. 

Oligophenylethoxysiloxanes are used as modifiers for various polymers to improve their weather resistance and other technical characteristics, as well as to increase the heat resistance of coatings. E.g., PES-50 is used to modify polyethers, aciylic and epoxy polymers PES-80 is used to modify alkyd and urea-formaldehyde resins. Besides, PES-80 is used as an additive in paints and enamels (to improve their flow properties, gloss and colour), as well as in concrete mixes (to improve the water resistance and durability of concrete works). 

The polymer concretes are distinguished by the nature of the binder e.g., furan, polyester, epoxy, phenol formaldehyde, carbamide, and so on. The classification of the main types of polymer concrete according to the kind of synthetic resins involved is shown in Figure 1.2 [7],... 

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],... 

Polymer concrete samples of four compositions (Table 1.2) measuring 4 x 4 x 16 cm are prepared. Control samples were placed in a desiccator containing moisture absorption silica gel composition. Other samples were in environments with various humidity. The influence of environmental humidity on the compressive strength, modulus elasticity, and moisture absorption of furfurol-acetone, epoxy, polyester, and rubber (RubCon) polymer concrete samples are shown in Tables 1.3-1.5 and Figures 1.4 and 1.5. 

Experiments similar to those previously described were carried out with epoxy and polyester polymer concrete samples (compositions 3 and 5, Table 1.2). 

Tests show that the epoxy-rubber coating strength of reinforced concrete beams reduces deformability of the reinforced concrete beams in bending, especially before crack formation in concrete the most favorable results are obtained for beams with a polymer concrete layer on three sides. 

Recent developments in this field seem to suggest that both epoxy or polyester resins are often times used for similar applications with no apparent difference in the performance of the materials. Ohama and co-workers (15) compared the resistance of polymer concretes to boiling water for periods of up to 12 months and found that epoxy resins were more resistant than orthopthalate based... 

Vipulanandan, C. and Paul, E. 1990. Performance of epoxy and polyester polymer concrete. ACI Mater. /., 87, 3, 241 (American Concrete Institute). 

VE polyurethane resins have mechanical properties similar or superior to those of conventional VE and epoxies. Characteristics include a heat distortion temperature of 120C (248F). Ultimate elongation of an unreinforced molding compound without fillers is 5.5% tensile strength is 80 MPa and flexural strength 150 MPa. The resins can be custom-formulated. Applications include customized automobile parts, recreational vehicles, outdoor equipment, tubs/showers and electrical parts. The resins are suitable for standard molding processes some were specifically developed for pultrusion, RIM, foam, adhesive, and polymer concrete applications. 

M. C. S. Ribeiro, P. R. Novona, A. J. M. Ferreia and A. T. Marques Flexural performance of polyester and epoxy polymer mortars under severe thermal conditions. Cement Concrete Composites Vol.26, No.7 (2004), pp.803-809. 

Czamecki and Lukowski [61] mention the acryl polymers added at p/c=0.1, which provide the better abrasion resistance, important for bridge pavements and industrial floors and improve the other properties typical for these polymer-cement concretes. The authors [61] mention also the epoxy-cement concrete, the only practically used composite, in which the polymer structural hardening occurs simultaneously with cement hydration [61]. 

Uses Epoxy for hard coatings (glass, metal, optical, plastic, PVC floor, paper, wood), electronics, and inks (flexo, gravure, litho, offset, screen), sealants, adhesives (anaerobic, binder, pressure sensitive, structural), polymer concrete... 

Chem. Descrip. Polyortypropylenediamine Uses Epoxy curing agent in surface coatings, heat-cured sol n. coatings, laminates, potting, casting, reinforced composites, adhesives, polymer concrete, tactic foam, reactive solvent Properties Colorless to si. yel si. hazy liq. sol. in most hydrocarbons and... 

Chem. Descrip. Polyethylene polyamine epo) curative Uses Epoxy curing agent for casting, secondary containment tooling, mortars, and polymer concrete, and as part of hardener package for coatings to shorten set time and improve solv. resist. 

Binders used for polymer concrete include epoxy resins (EP), unsaturated polymer resin (UP), vinyl ester resin (VE), methyl metacrylate (MMA) and furan resins [9-11]. 

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