Determining the physical properties of polymer in different admixtures used for self-compacting cement paste by ESEM

Abstract

The aim of this study is to determine the physical properties of the polymer in plasticizers used for self-compacting cement pastes by environmental scanning electron microscopy (ESEM) method. Images of fresh cement paste containing cement, water, and plasticizer prepared by using 3 different types of plasticizer were examined by ESEM. Lignosulfonate-based, naphthalene sulfonate-based, and polycarboxylate-based plasticizers were added to the cement paste at a rate of 1% by weight of the cement. Images of the fresh cement pastes were obtained using ESEM within the first 3−5 min after mixing. As a result, the presence of electrostatic and steric effect forces of cement pastes prepared with the polycarboxylate-based additive was determined by ESEM analysis. In the ESEM analysis of the self-compacting cement paste, the diameter of the polymer that forms the steric force effect of the polycarboxylate-based additive was measured as 100−160 nm and the polymer length was 1−2 μm. The presence of an electrostatic force was determined from the brightness around the cement particles by ESEM image analysis.