Epoxy polymer concrete properties

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). 

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. 

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]. 

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... 

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). 

Popovics, S., Modification of portland cement concrete with epoxy as admixture. In Polymer Concrete Uses, Materials, and Properties SP-891 ed., J.T. Dikeou and D.W. Fowler, American Concrete Institute, Detroit, 1985, pp.207-229. 

The use of filling cracks with epoxy mass or with hard flexible polymer is also effective in the same case. Especially, repair of the cracked cement-polymer composites with addition of SBR is effective, because restores properties of floor concrete and also of the repair covering system. Unfortunately, both previously mentioned repair methods are inadequate in cases of large deformations, because of low value of the ultimate strain angle (y < 0.5 %). Overcome of this value causes appearing of new damage in concrete, close to the repair joint. 

Chem. Descrip. Uncatalyzed mercaptan polymer Uses Epoxy hardener, accelerator tor amides, amines, and amido-amines in conventional and high-solids applies., fast-set concrete adhesives, castings, potting, laminates Features Requires amine catalyst tor activation Properties Gardner 2 max. color sp.gr. 1.15 dens. 9.6 Ib/gal vise. 100-150 poise gel time 4.5-6.5 min (30-50 g) After 7 day 25 C cure tens, str. 5900 psi elong. 3.75% flex. str. 10,000 psi 100% solids Capcure 40 sec HV [Cognis/Coatings Inks]... 

An important feature of polymer-modified mixes is their improved bonding to old concrete or steel surfaces, which makes them particrrlarly siritable for repair work (Schulze, 1999). The addition of polyvirtyl alcohol, polyvirtyl acetate or epoxy resin to the fresh mix appears to be most effective in this respeet (Stark et ai, 1996). An improved bond may also be achieved between the fibers and eemerrt matrix in fiber-reinforced composites, resrrlting in irrrproved strength properties (Fn et al, 1996). 

Epoxy resin has superior properties such as high adhesion and anticorrosion, and has widely been used as adhesives and anticorrosives in the construction industry in the world. Provided the incorporation of the epoxy resin into cement mortar can give its superior properties to the mortar, it is possible to produce a highly polymer-modified cement mortar. The first patent of an epoxy-modified cement system was taken by Donnelly in 1965 [1]. Since the patent, 30 or more papers on the epoxy resin modification of the cement mortar and concrete have already been published [2]. Most epoxy resin-based cement modifiers dealt with in the papers are specially compounded by the manufacturers, and the procedures for mixing them to fresh mortar and... 

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