Principles of Polymer Modification for Cement Composites

Polymer-modified mortar and concrete are prepared by mixing either a polymer or monomer in a dispersed, powdery, or liquid form with fresh cement mortar and concrete mbctures, and subs uently curing, and if necessary, the monomer contained in the mortar or conoete is polymerized in situ. The polymers and monomers used as cement modifiers are shown in Fig. 2.1. 

Several types of polymer-modified mortars and concretes, i.e., latex-redispersible polymer powder-, water-soluble polymer-, liquid resin-, and monomer-modified mortars and concretes, are produced by using the polymers and monomers shown in Fig. 2.1. Of th, the latex-modified mortar and concrete are by far the most widely used cement modifiers. 

Although polymers and monomers in any form such as latexes, water-soluble polymers, liquid resins, and monomers are used in cement composites such as mortar and concrete, it is very important that both cement hydration and polymer phase formation (coalescence of polymer particles and the polymerization of monomers) proceed well to yidd a monolithic matrix phase widi a network structure in which the hydrated cement phase and polymer phase interpenetrate. In the polymer-modified mortar and concrete structures, aggregates are bound by such a co-matrbc phase, resulting in the superior properties of polymer-modified mortar and conoete compared to conventional. 

Redispersible Polymer Powders Water-Soluble Polymers Liquid Resins Monomers 

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