Title: Principle of Latex Modification and Some Typical Properties of Latex-Modified Mortars and Concretes Adhesion; Binders (materials); Bond (paste to aggregate); Carbonation; Chlorides; curing; diffusion;
Author(s): Yoshihiko Ohama
Publication: Materials Journal
Appears on pages(s): 511-518
Keywords: adhesion; binders (materials); bond (paste to aggregate); carbonation; chlorides; curing; diffusion; durability; mortars (material); freeze-thaw-durability; latex; permeability; plastics, polymers and resins; monomers; polymer-portland cement-concrete
Latex-modified mortars and concretes employing various polymer latexes have been developed actively for more than 60 years and widely used as construction materials because of their good performance-cost ratio. This paper reviews the principle of latex modification in the process technology of latex-modified mortars and concretes and discusses their typical properties. Such properties are mainly characterized by a polymer-cement comatrix they form. The formation process of the comatrix is explained by a three-step, simplified model. The possibility of some reactions between polymers, cement, and aggregates is also discussed. The author proposes a binder-void ratio law that expands Talbot's void theory. The reviewed typical properties of hardened latex-modified mortars and concretes include strength, adhesion, pore structure, impermeability, and durability (freeze-thaw resistance, chloride penetration resistance, carbonation resistance, and weatherability). In general, these properties are strongly affected by the polymer-cement ratio.