GB1484057A - Adjuvant for a self-smoothing mortar - Google Patents

Abstract

1484057 Mortars RHONE-POULENC SA 28 Oct 1974 [29 Oct 1973] 46437/74 Heading C1H A self-smoothing mortar comprises cement (e.g. Portland cement), sand, water, a specified adjuvant and, optionally, an accelerator (e.g. based on calcium formate) for shortening the setting time of the mortar. The adjuvant comprises 30-80% by weight of a filler with a specific surface area of at least 10 m.<SP>2</SP>/g., 10-40% by weight of an emulsifier or emulsifying system, deposited on the filler, and at least 5% by weight of a hydrophilic material having, by its chemical nature, the capacity to retain water. The filler may be kaolin, alumina, calcium carbonate, calcium magnesium carbonate, barium sulphate or calcium sulphate and the emulsifier may consist of 0-40% of a non-ionic surface-active agent (e.g. a derivative of an alkyl-phenol, fatty acid of fatty alochol, especially an ethylene oxide derivative of octyl- or nonyl-phenol) and 60-100% of an anionic surface-active agent (e.g. chosen from sulphated derivatives of amino-alcohol amides, amide derivatives of amino-sulphonic acids of amino-acids, sulphonated derivatives of mono- or di-esters, and alkylbenzene-sulphonates). The water-retaining agents mentioned are alginates, cellulose derivatives (e.g. hydroxyalkyl- or carboxymethyl-cellulose), polyacrylic acid derivatives (e.g. sodium polyacrylate) and polyvinyl alcohols (which may be partially hydrolysed). The adjuvant may be made up in dry powder form, but, according to a modification of the invention, the self-smoothing mortar may be prepared directly from its ingredients, in which case it is possible to incorporate the emulsifier or emulsifier system into the mortar in the form of a liquid which is introduced into the mixing water for the mortar and not as a deposit on the filler.