Concrete polymer impregnated

After impregnation the monomer in the system is polymerised by either thermal-catalytic or promoted-catalytic or ionising radiation methods. The catalytic methods are more commonly used than the latter [11]. 

The thermal-catalytic method involves the nse of chemical initiators and heat. Commonly used initiators include benzoyl peroxide (CFRP), azobis-isobutyronitrile, a-tert- mXy -azoisobutyronitrile, tert-butylperbenzoate, and methylethylketone peroxide (MEKP) [11]. 

In order to allow polymerisation at low ambient temperatures, the promoted-catalytic method may be used. This is achieved by promoters which are reducing agent compounds 

Another way of achieving polymerisation at low temperatures is by using ionising radiation from gamma rays emitted by cobalt-60. The radiation energy absorbed by the monomer results in the production of free radicals. The radiation method does not require initiators or promoters. On the other hand, the cost of radiation source is high and polymerisation rate may be low [11]. 

The selection of a monomer for PIC depends on its impregnation and polymerisation characteristics. Vinyl monomers such as acrylonitrile, methyl methacrylate, styrene and vinyl acetate containing an initiator are the most commonly used materials for PIC production. 

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Sadegzadeh, M. and Kettle, R. J., Abrasion resistance of polymer impregnated concrete. Concrete, 32-34, May (1987). 

Strength and Elastic Modulus of Polymer Impregnated Concrete, Cem. Concr. Res. (1971) 1, 631-644. 

Polymer-impregnated concrete. 2. Polymer-impregnated mortar. 

The mechanical properties, the corrosion stability, and some useful properties are the reasons for the continuous interest shown in polymer-concrete composites by various design, research, and production organizations. The most important types of polymer-concrete composites are polymer-impregnated concrete (PIC), polymer-cement concrete (PCC), and polymer concrete (PC). 

Keywords Concrete-polymer composites. Polymer-modified concrete. Polymer concrete. Polymer-impregnated concrete. Principles of process technology. Research and development. Standardization work. Sustainable concrete-polymer composites. History, The recent and future trends. 

S. Mindess The fracture of fiber reinforced and polymer impregnated concrete A review, in Fracture Mechanics of Concrete, Elsevier Science Publishers, Amsterdam (1983), pp.481-501. 

Polymers. The purpose of adding polymers to the concrete matrix is to improve the characteristics of the fresh concrete (such as workability) and also to enhance the hardened properties such as flexural strength, modulus of elasticity and adhesive performance [8]. The incorporation of polymers into concrete may be in the form of polymer modified concrete (PMC), polymer impregnated concrete (PIC) or as polymer concrete (PC) [9], For this project, the objective was to develop an ultra-lightweight concrete material using Portland cement as the main binder modified with a suitable polymer - thus a PMC application. The polymer modifiers selected for the development of the ultra-lightweight thin filmed material were a commercially available SBR latex as well as a readily available acrylic polymer. 

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. 

Fig. 9.34 Comparison of mechanical properties of normal concrete and polymer impregnated concrete (according to [171]) 1 normal concrete, 2 soaked with methyl metacrylate, 3 soaked with ethyloacrylonitryl. The coefficients illustrating the strength increase and the elasticity increase due to impregnation are scaled on the axis of ordinates...

This model is analogous to the porosity model for polymer-impregnated concrete discussed in Section 11.3.3.5. 

In this type of system, a matrix with a more or less continuous pore system is filled with a second component. The pore system is, however, fixed during the formation of the matrix itself. Thus one might expect some differences between polymer-impregnated concretes and the latex-modified concretes discussed above for example, the latter are inherently more porous because porosity will always develop during curing, regardless of the presence of polymer. In both cases, however, the cement and polymer phases appear to form continuous and intertwined networks. 

Property Concrete control specimen Polymer- impregnated concrete "... 

Figure 11.13. Polymer-impregnated concrete compressive stress-strain curves as a function of polymer composition (hydraulic tester) KSI = psi X 10". MMA and BA refer to methyl methacrylate and n-butyl acrylate, respectively. (Manson et al, 1973.)...

This chapter will be devoted to the consideration of nascent research undertakings, possible new materials, and as yet unanswered research questions. First, an effort will be made to codify and classify composite materials and polyblends with respect to topological considerations. We will examine what other ways may possibly exist to make new combinations of two types of polymeric molecules. How many ways exist to mix two kinds of polymer molecules What relationships can be developed among such diverse materials as particulate and fiber-reinforced plastics, polymer-impregnated concrete, and foams, paint films, etc. ... 

Polymer-impregnated concrete and mortar elements are being employed in applications where an exceptionally high performance of the material is required, such as in highly corrosive environments. 

In sealed or polymer impregnated concrete, corrosion may not occur even at a very high Cl- concentration if no oxygen or moisture is present to fuel the corrosion reaction. 

As an additive to cement and reinforcer to concrete Polymer modified concrete (PMC), polymer concrete (PC), polymer impregnated concrete (PIC), fibre-reinforced plastic (ERP) rebars... 

The earliest indication of the use of polymers in concrete was apparently in 1909, in USA when a patent for such use was granted to Baekeland and in 1922 in France and in 1923 in UK [38]. Polymers can be added by three different methods into normal concrete, leading to polymer impregnated concrete (PIC), polymer modified cement concrete (PCC) and polymer concrete. 

Concretes with polymers are generally classified into three categories as polymer concrete (PC), polymer Portland cement concrete (PPCC), which is also known as latex-modified concrete (LMC) and polymer-impregnated concrete (PIC) according to their process technologies. 

Dahl-Jorgensen, E., Chen, W. R, Manson, J. A., Vanderhoff, J. W., Liu, Y. N. (1974) Polymer-impregnated concrete Laboratory studies, ASCE/EIC/RTAC Joint Transportation Engineering Meeting, Montreal, July 14-19. 

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