Physico-chemical characteristics of some polymer cement composites

The electrical conductivity of cement pastes can give an indication of the initial hydration of the cement pastes and early formation of products. In this study, sulphate-resisting cement (SRC) pastes were prepared with diffe rent doses of two synthesised admixtures, namely phenol formaldehyde sulpho nate (PhFS) and melamine formaldehyde sulphonate (MFS). This work is aimed to evaluate the effect of PhFS and MFS on the hydration reaction of cement pastes during the first 24h by determining the initial, final setting times and the electrical conductivity changes, as well as the effect of these po lymers on the hydration progressing up to 90 days by determining the chemic ally combined water content and gel/space ratio of each paste at different intervals of time (1, 3, 7, 28 and 90 days). (C) 2001 Elsevier Science B.V. All rights reserved.