Title: Influence of Cellulose Ether Particle Size on Water Retention of Freshly Mixed Mortars

Author(s): L. Patural, A. Govin, B. Ruot, O. Devès, and P. Grosseau

Publication: Symposium Paper

Volume: 262

Issue:

Appears on pages(s): 261-271

Keywords: cellulose ethers; cement; mortar; particle size; water retention.

DOI: 10.14359/51663237

Date: 10/1/2009

Abstract:
Cellulose ethers are polymers frequently introduced into mortar formulations in order to improve water retention capacity and workability of the freshly-mixed materials. Physico-chemical parameters of these admixtures (molecular weight, granulometry, substitution degrees, etc.) seem to have a strong influence on mortar water retention capacity. In this paper, the influence of cellulose ether particle size was studied. Two behaviors were highlighted regarding the particle size effect on mortar water retention. On the one hand, for cellulose ethers providing intermediate water retention, this parameter is fundamental: the thinner the particles, the better the water retention. The increase in water retention was explained by the rate of dissolution of every fraction which was faster for the thinnest particles. On the other hand, for admixtures providing strong water retention, the effect of this parameter was weaker or not relevant. Indeed, a cellulose ether concentration threshold was noticed, justifying this behavior.