Polyester polymer concrete

Polyester resins like epoxy are a type of thermosetting resins, obtained by polycondensation. They have a low viscosity, and materials that are based on them have high mechanical and electrical insulating properties and high resistance to acids, gasoline, oils. 

Because of low cost, the most widely used unsaturated polyester polymer is in the form of 60% to 80% solutions of the prepolymer in copolymerizable monomers such as styrene and a mix of styrene with methyl methacrylate. During hardening, the polyester prepolymer and the monomer react through their unsaturated groups (double bonds). 

It should be added that polyester resins are toxic, and with poor stirring of the mixture components the probability of stratification and level-by-level curing of the composition is high. 

Polyester PC is used in various procast and cast-in-place applications in construction works, public and commercial buildings, for the manufacture of sanitary engineering, cladding of composite pipes in bathrooms and toilets, stairs, and chemical-resistant floors [2,6,7], 

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FIGURE 1.3 Most common aggregate systems used in PC. (From V. Y. Garas and C. Vipulanandan, Review of Polyester Polymer Concrete Properties, http //www2.egr. uh.edu/ civebl/CIGMAT/03 poster/ll.pdf.)... 

Polyester polymer concrete resists oxidizers, acids, oils, and petroleum products, but there is not enough resistance to alkaline solutions and water. The strength of polyester PC in water decreases faster than in solutions of inorganic salts and some acids therefore, resistance in acid solutions can simultaneously serve as an estimate of water resistance. For example, the flexural strength of the PC, immersed in a 10% solution of sulfuric acid or 10% sodium chloride solution is reduced by 30% after 80 days of immersion. 

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

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. 

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

N. Dharmarajan and C. Vipulanandan Influence of glass fiber reinforcement on polyester polymer concrete, in SPE Technical Papers, The 45th Annual Technical Conference, Society of Plastics Engineers, Stamford, Connecticut (1987), pp. 1258-1261. 

R. Griffiths and A. Ball An Assessment of the Properties and Degradation Behaviour of Glass-Fiber-Reinforced Polyester Polymer Concrete, Composites Science and Technology Vol. 

Polymers for Advanced Technologies 6, No. 11, Nov. 1995, p.688-92 MAKING POLYMER CONCRETE AND POLYMER MORTAR USING SYNTHESISED UNSATURATED POLYESTER RESINS FROM POLY(ETHYLENE TEREPHTHALATE) WASTE Abdel-Azim A AA Attia IA Egyptian Petroleum Research Institute Carro,Ain Shams University... 

High-temperature cement formulations are basically polymer concrete. Mainly unsaturated polyesters or vinyl ester resins with allylphthalate as vinyl monomer are in use [927]. Cming is achieved with peroxides, which decompose sufficiently fast at temperamres between 120° and 200° C. Polymer concrete requires additional materials, which compensate shrinkage. 

Finally some important properties of cement concrete, polymer concrete, and sulfur concrete are compared with each other. For the polymer concrete the data of a commercial polyester concrete were used. 

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. 

Keywords Polymer concrete, polyester, polyethylene, recycled materials... 

The high cost of resins used in the production of polymer concrete (PC) makes the material expensive relative to cement-based materials. Not surprisingly, a recent survey ranked lower cost resins as the most important future need for PC [1], Recently, some work has been done on the production of unsaturated polyester resins based on recycled poly (ethylene terephthalate), PET [2], The PET wastes are typically found in used beverage bottles, and many states have passed legislation to collect and recycle these bottles. If specially formulated, the unsaturated polyester could be used in the production of PC [3],... 

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],... 

Polymer concretes based on phenol-formaldehyde, acetone-formaldehyde resins and monomers, and methyl methacrylate are much less common. Phenolic resins are similar to furan in many physical and mechanical properties. However, they are unstable in alkalis like polyester resins [7],... 

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. 

As shown in Table 2.7, the coefficient of chemical resistance of RubCon is 1.0 for water, 0.81-0.95 for all mineral acids (exception is KCI = 0.69 for 36% solution of hydrochloric acid), 0.82-0.95 for organic acids, 0.82-0.91 for alkalis, 0.88 for solvents and petroleum products, and 0.84-0.86 for solution of salts. The analysis of experimental data has shown that RubCon offers universal chemical resistance many times higher than ordinary Portland cement concrete and surpasses the chemical resistance of polyester, polyepoxy, and vinyl ester polymer concrete. It is worth noting that penetration depths of 5% nitric and 36% solution of hydrochloric acids into RubCon sample bodies were 3, 4, and 5.1 mm, respectively the penetration ability of these acids is higher as compared with other corrosive environments. 

RubCon offers universal chemical resistance many times higher than ordinary Portland cement concrete and surpasses the chemical resistance of polyester, polyepoxy, and vinyl ester polymer concretes. 

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... 

There are also dimethylaniline with dibenzoyl peroxide at room temperature (for normal/long gel times) dimethylparatoluidine (for very short gel times) cobalt octoate (mainly used with ketone peroxides for polyesters at room and elevated temperatures) cobalt/amine very high reactivity with ketone peroxides for very fast cure (for example polymer concrete) and vanadium special for ketone peroxide. 

The Society of Materials Science, Japan (JSMS) Recommendation and Guide (Japan) PC Recommendation for structural design of polymer concrete Guide for mix design of polyester resin concrete... 

Y. Ohama Determination methods for working life of polyester resin concrete, in Polymers in Concrete, SP-58, American Concrete Institute, Detroit (1978), pp.31-40. 

Uses Crosslinking agent for peroxide-cured rubber compds., irradiated coatings, polyesters, adhesives, concrete polymers, dental polymers, electronics, inks, plastisols, sealants Trade Names Bisomer E(2)BADMA Bisomer E30W Trade Names Containing Bisomer E(10)BADMA... 

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