In this study, effects of polymer-cement (P/C) ratio, glass transition temperature (Tg); amounts of functional monomers (acrylic acid, hydroxypropyl methacrylate, ammonium polyacrylate, diacetone acrylamide) on properties of polymer cement mortar were investigated. According of the tensile test, breaking elongation (ε) and the tensile strength (δ) of polymer latex-cement composites with low P/C ratio were mainly depended on Tg, differential Tg value between layer and shell in acrylic latex (ΔTg) and the amounts of functional monomer. Additionally, at a low P/C ratio, it was found that the cross-linking rate had small effect of tensile property. It was determined that the waterproofing coatings III with a low P/C (0.12) showed the excellent tensile property when the Tg and the ΔTg of the acrylic latex were controlled at -24°Cand -20°C, respectively.

A fast algorithm for the computation of radial- harmonic-fourier moments (RHFM) is presented in this paper. This algorithm is based on some properties of the radial- harmonic-fourier (RHF) basis functions. As RHF basis functions have specific symmetry or anti-symmetry about the x-axis, the y-axis, the origin, and the straight line of y=x, we can compute one eighth range of the RHF basis functions instead of the whole. Both theoretical analysis and experimental testing show that the fast algorithm makes the time of the computation shorter than the direct method.

Two waterborne polyurethane latexes with different tensile strength were employed to modify mortar and the properties of mortar including air entrainment, setting behavior, compressive and flexural strength were investigated. The results show that curing methods, polymer-cement ratio and water-cement ratio have a significant impact on the compressive and flexural strength. The strength of mortar increased under dry curing condition in the range of the polymer-cement ratio from 0.005 to 0.05 (by weight) at water-cement ratio of 0.5. The hydration of the cement containing waterborne polyurethane latexes was not affected and no visible film was found in SEM images.