Portland Cement Paste Modified by Polyvinyl Alcohol Acetate

Some water-soluble polymers have proved potentials for improvement in properties of Portland cements. This work was designed to investigate the simultaneous effect of both W/C- and P/C-ratios on flexural strength of type V Portland cement pastes containing polyvinyl alcohol acetate. The obtained results confirmed the strong effect of W/C-ratio on the effectiveness of the added polymer so that there exist optimum values for both W/C and P/C-ratios. Pastes prepared at optimum W/C and P/C-ratios of respectively 0.30 and 0.016 exhibited the highest flexural strength which was more than two times the strength of unmodified pastes. Further measurements on hardened paste specimens prepared at W/C=0.30 show that increasing the P/C-ratio increases dry bulk specific gravity of the specimens and result in significant reductions in both total permeable pore volume and water absorption of the specimens confirming the effective packing caused by polyvinyl alcohol acetate.

کلیدواژه ها:

Polyvinyl Alcohol Acetate ، Portland Cement