Original paper(Vol.53 No.10 pp.1103)

Effects of Polymer Dispersion and Redispersible Polymer Powder on Properties of Polymer-Modified Mortars

Hiroyuki SAKAKIBARA, Shigehiro ANDO, Keiiti OSAKI , Akihiro KAWAKAMI, Takahiko SASAKI, Hiroshi UEDA and Shinji FUJIWARA

Abstract:Various types of polymer-modified mortar have recently been used to repair deteriorated concrete structures. The type of the polymer dispersion or redispersible polymer powder is considered to determine the physical properties of hardened polymer cement mortar. In this study, a prototype of polymer-modified mortar was made using such cement admixtures as polymer dispersion and redispersible polymer powder . Then, the physical properties of the polymer-modified mortar were measured to examine the effects of polymer dispersion and redispersible polymer powder on the physical properties of hardened polymer-modified mortar. It was found that the physical properties of polymer-modified mortar with a water-cement ratio of 0.4, a sand-cement ratio of 2.0, a polymer-cement ratio of 0.05, a flow value of mortar of 180 } 10 and a mass of unit volume of 2.1 } 0.1 varied according the types of polymer dispersion and redispersible polymer powder. A substantial variances were found in drying shrinkage and resistance to neutralization. It was suggested that the depth of neutralization were affected by the pore volume for pore diameters of 100ƒÊm and over in polymer-modified mortar.

Key Words:Polymer dispersion, Redispersible polymer powder, Polymer-modified mortar, Dring shrinkage, Neutralization, Pore size distribution