Concrete polymer applications

Photoeffect sensitization in polymers is realized by means of charge-transfer complexes, dyes, polymers, heterogenous and multilayer structures. Every method permits us to obtain some information about photogeneration, charge transfer processes and can be used for concrete practical applications. 

The long range objectives of the joint program are the investigation and development of a concrete-polymer composite as a new construction material. The program includes the development of techniques for preparing concrete-polymer material, measurement of the physical and chemical properties, preparation of full-scale concrete products, and the conceptual design and evaluation of various specific applications. 

Monomer Selection. The selection of a monomer to form a concrete-polymer material depends on the end application of the material, which in turn depends on the properties of the polymer, and on the cost, process requirements, and properties of the monomer. 

Several possible applications of concrete-polymer material includes sewer and pressure pipe, building material for housing, underwater structures, railroad ties, and chemically resistant material of construction for large desalination plants. The incorporation of colored dyes with the monomer allows concrete-polymer material to be considered for various esthetic applications, such as in decorative wall and floor tile. 

Polymer concretes show excellent mechanical properties and chemical resistance compared with conventional cement concretes. Polymer concretes can be cured quickly by the use of curing agents. Thus, the applications of polymer concretes are being increased. One of the popular polymers for polymer concretes is unsaturated polyester (UPE) resin. The properties of UPE resin can be modified by changing its molecular features. For the synthesis of the resin, phthalic anhydride or isophthalic acid as well as maleic anhydride can be employed to modify the mechanical properties or hydrothermal resistance. Terephthalic acid which is also used for the synthesis of poly ethylene terephthalate (PET) enhances the thermal resistance of the cured UPE resin. However, the synthesis of unsaturated polyester resin from terephthalic acid is difficult. One method to synthesize unsaturated polyester from terephthalic acid is the use of recycled PET. 

Soh, Y.S. (1992), Development of Lightweight Polymer Cement Concrete, Korea-Japan Symposium on Development and Application of Concrete-Polymer composits, Chonbuk National Univ., pp. 172-159. 

Surface Barriers The application of an overlay of low-slump concrete, latex-modified concrete (EMC), high-density concrete, polymer concrete, or bituminous concrete with membrane on the existing concrete provides a barrier that impedes continued intrusion of chloride anions, moisture, and oxygen that are necessary for continued corrosion. These barrier systems may be used only after decontamination because corrosive agents get trapped in the concrete, leading to loss in its capacity to function properly. 

Although concrete-polymer composites are currently used as common construction materials in various applications globally, it appears to have reached a plateau in terms of their new research and development in the advanced countries except for sustainable concrete-polymer composites [86], However, their research and development activities will progress rapidly in the developing or emergent countries in the near future. 

Y. Ohama Application of concrete-polymer composites and recent trends in their research and development (in Japanese). Concrete Journal Vol.28, No.4 (1990), pp.5-17. 

Kukacka, L. E., Romano, A. J., Reid, M., Auskern, A., Colombo, P., Klamut, C. J., Pike, R. G., and Steinberg, M. (1972), Concrete-Polymer Materials for Highway Applications, Progress Report No. 2, Brookhaven National Laboratory, report BNL 50348. 

The reliable formulae and extensive test results for polymer and fibre-reinforced composites are scarce. Simple relations for the prediction for shrinkage and creep of ordinary concretes for application in structural design were given already in CEB-FIP Model Code (1990) with coefficients to allow for actual conditions. Later, so-called Model B3 was recommended by ACI (1999) and extensively discussed by Bazant and Baweja (1995). A sHghtly different approach was proposed in EN 1992 (2004) and detailed comments may be found in Vandewalle (2000). 

This section is limited to the application of methods of mathematical optimization to materials with cement-based matrices, like ordinary concretes, polymer concretes, fibre-reinforced concretes, etc. Other methods of improving the material design by separate analyses of particular aspects and criteria, or by computer assisted comparisons of a number of designs to select the best one, are mentioned only briefly. 

MAJOR PRODUCT APPLICATIONS concrete modification, composite, building materials, polyester mortar MAJOR POLYMER APPLICATIONS PP, PE, PU, PET... 

Today, cement and concrete replace stone in most large structures. But cement, too, is a ceramic a complicated but fascinating one. The understanding of its structure, and how it forms, is better now than it used to be, and has led to the development of special high-strength cement pastes which can compete with polymers and metals in certain applications. 

There are less exotic ways of increasing the strength of cement and concrete. One is to impregnate it with a polymer, which fills the pores and increases the fracture toughness a little. Another is by fibre reinforcement (Chapter 25). Steel-reinforced concrete is a sort of fibre-reinforced composite the reinforcement carries tensile loads and, if prestressed, keeps the concrete in compression. Cement can be reinforced with fine steel wire, or with glass fibres. But these refinements, though simple, greatly increase the cost and mean that they are only viable in special applications. Plain Portland cement is probably the world s cheapest and most successful material. 

These novel organic polymers were not developed solely for the CW or BW treatment market but are for much wider application. These same value-adding process additives are regularly incorporated into products for industrial and domestic cleaning, concrete, pulp and paper, metal finishing, paints and surface coatings, wastewater, seawater distillation, drilling muds, secondary oil-recovery, plastics extrusion, fibers, rubbers, and a host of other areas. 

As a final application of the profiling technique, the sensor for large depth measurements described in Section 2.4.2.5 was used to resolve multi-layer polymer coatings on concrete samples. Such coatings are used to protect concrete from degradation and corrosion. They are applied to the concrete surface to reduce the porosity in the upper first millimeters to prevent the penetration of water and... 

Of the several types of the polymer-modified mortars and concretes used for various construction applications, latex-modified mortar and concrete are by far the most widely used materials. Latex-modified mortar and concrete are prepared by mixing a latex, either in a dispersed liquid or as a redispersible powder form with fresh cement mortar and concrete mixtures. The polymers are usually added to the mixing water just as other chemical admixtures, at a dosage of 5-20% by weight of cement. Polymer latexes are stable dispersions of very small (0.05-5 pm in diameter) polymer particles in water and are produced by emulsion polymerization. Natural rubber latex and epoxy latex are exceptions in that the former is tapped from rubber trees and the latter is produced by emulsifying an epoxy resin in water by the use of surfactants [87]. 

E. L. Kukacka, ed., Applications of Polymer Concrete, ACI, Detroit, Mich. (1981). 

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