Concrete monomer impregnation

Polymerization of monomer-impregnated concrete was initially carried out with 60Co gamma radiation. A principal advantage of using radiation is that free radical chain reactions can be induced at ambient temperature. This limits vaporization loss and may produce a better concrete-polymer bond. The disadvantages are the dose requirements and the relatively high initial investment required for the radiation source and facility. 

Polymerization of coatings on electrical conductors and paper and monomers impregnated into wood and concrete. (Machine radiation generally is preferred in applications involving thin materials.)... 

Morrison, G.L., Virmani, Y.P., Stratton, F.W. and Gilliland, W.J. (1976). Chloride Removal and Monomer Impregnation of Bridge Deck Concrete be Electro-osmosis. Kansas DoT Report. FHWA-Ks-RD. 74—1. 

Polymer concrete is a composite material formed by polymerising a monomer and aggregate mixture. There is no other cementitious material present in it. PPCC (or LMC) is a Portland cement concrete produced usually by replacing a specified portion of the mixing water with a latex (polymer emulsion). It can also be produced by adding a monomer to fresh concrete with subsequent in situ curing and polymerisation. PIC is a hardened Portland cement concrete with impregnated monomer which is polymerised in situ. 

Hardened portland cement concrete with impregnated monomer which is polymerised in situ. 

Porous objects such as plaster and concrete can be strengthened by UP impregnation. However vinyl monomer impregnation is often substituted for UP impregnation since vinyl monomers have much lower viscosities and they penetrate into much smaller pores [12], Strengthening of the lo< archeological objects, or adhesion of broken parts can be successftilly accomplished by UP resins. 

Evacuation, Soaking, and Pressurizing. The impregnation of concrete with monomer is essentially a displacement of the air in the void... 

For processing purposes the monomer should have a relatively high boiling point or low vapor pressure under polymerization conditions to limit vaporization losses between the time the concrete specimen is impregnated and the time it is polymerized fully. 

Promoters have been used to reduce the temperature at which the catalyst normally decomposes and to effect polymerization at ambient temperature. The use of a combination of monomer, catalyst, and promoter may have some advantage for field impregnation of cast-in-place concrete. 

To provide improved control over the polymerization and additional safety, it is possible to add the catalyst to the concrete mix before curing and to add the promoter to the monomer used for impregnating. Benzoyl peroxide when incorporated in premixed concrete will initiate polymerization of methyl methacrylate at room temperature when cobalt naphthenate is added to the monomer used for impregnation. 

Very hard coatings may be obtained by irradiation of polymerized varnishes on wood or metals. Irradiation of wood impregnated with a monomer leads to waterproof products of high stability and hardness. Similarly to these wood-polymer combinations, concrete-polymer combinations can also be produced that exhibit high resistivity in water, particularly in seawater. 

PIC is a precast and cured portland cement concrete that has been impregnated with a monomer that is subsequently polymerized in situ. This type of cement composite is the most developed of polymer-concrete products. PCC, on the other hand, is a modified concrete in which a part (10%-15% by weight) of the cement binder is replaced by a synthetic organic polymer. It is produced by incorporating a monomer, prepolymer-monomer mixture, or a dispersed polymer (latex) into a cement-concrete mix. To effect the polymerization of the monomer or prepolymer-monomer, a catalyst (initiator) is added to the mixture. The process technology used is very similar to that of conventional concrete. So, unlike PIC which has to be used as a precast structure, PCC can be cast-in-place in field applications. PC can be described as a composite that contains polymer as a binder instead of the conventional portland cement. 

The technology of concrete soaking with monomeric substance and subsequent m situ" polymerization is relatively new. According to Worn [171], it was initiated by Steinberg in 1968. Beside of the polymer impregnated concretes, there are also the polymer concretes (resin concretes) without cement and the polymer-eement concretes in the latter case cement is mixed with monomer and water to produce the concrete mixture . This question will be discussed in Chap. 10. 

Impregnation with monomers and oligomers that achieve a polymeric state within the structure is preferable, as it permits the treatment of practically all types of porous materials, such as concrete, soil, wood, brick and other ceramic materials, asphalt, and so on, and the impregnated material exceeds the original in strength. The treated materials capacity for deformation without breaking also increases, and density, tightness, chemical stability, and immunity to insects is improved. 

Polymers may be incorporated basically in three ways (a) by adding a polymerizable monomer to a concrete or mortar mix, and then curing both concrete and polymer (b) by adding a latex or an aqueous solution of a polymer to a mortar, or concrete mix, and then curing the composition in the presence of the polymer and (c) by impregnating a cured mortar or concrete with a monomer, and then polymerizing the monomer using thermal or radiation catalysis. 

Bis [[[4-(ethenyloxy) methyl] cyclohexyl] methyl] terephthalate 1,4-Cyclohexanedicarboxylic acid Dicyclopentenyl acrylate Dicyclopentenyl methacrylate Dimethyl maleate 2-Hydroxyethylethylene urea Hydroxypropyl methacrylate Jsooctyl acrylate 2-Phenoxyethyl methacrylate 3-[(Prop-1-en-2-yl) phenyl] prop-2-yl isocyanate N-Vinyl formamide monomer, concrete impregnation Methyl methacrylate monomer, concrete resurfacing Dicyclopentenyl methacrylate monomer, conductive polymers... 

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