Solvent exchange in partially saturated and saturated microporous systems - Length change anomalies

The results of a study to determine the volume stability of partially satur ated and saturated microporous systems subjected to the solvent exchange pr ocess are reported. Length change measurements of several microporous syste ms (hydrated Portland cement, calcium silicate hydrate (C-S-H), calcium hyd roxide (CH), vycor glass and molecular sieves) were monitored during immers ion in excess amounts of methanol, isopropanol, and dimethyl sulfoxide (DMS O). Single and double exchanges were performed to assess the effects of the initial exchange on the reversibility of the length changes observed. Infe rences were drawn from the length change results regarding the operative me chanisms responsible for volume change during the solvent replacement proce ss. (C) 2000 Elsevier Science Inc. All rights reserved.