Abstract: A methyl ethyl hydroxyalkyl cellulose (MEHEC), process for making the MEHEC, and a powder containing the MEHEC are disclosed. The MEHEC is provided with a DSmethyl from 1.5 to 2.5, a DSethyl from 0.005 to 0.15, and a MSalkylene-oxide from 0.005 to 0.2. The methyl ethyl hydroxyalkyl cellulose optionally includes an anti-oxidant. The MEHEC optionally does not have a combination of a DSmethyl of 2.2 or 1.8, a DSethyl of 0.05 or 0.1, and a MSalkylene-oxide of 0.1 and does not have a combination of a DSmethyl of 2.5 or 2.0, a DSethyl of 0.1, and a MSalkylene-oxide of 0.05. The MEHEC has very good biostability and is suitable for use in the building industry.

Abstract: A methyl ethyl hydroxyalkyl cellulose (MEHEC), process for making the MEHEC, and a powder containing the MEHEC are disclosed. The MEHEC is provided with a DSmethyl from 1.5 to 2.5, a DSethyl from 0.005 to 0.15, and a MSalkylene-oxide from 0.005 to 0.2. The methyl ethyl hydroxyalkyl cellulose optionally includes an anti-oxidant. The MEHEC optionally does not have a combination of a DSmethyl of 2.2 or 1.8, a DSethyl of 0.05 or 0.1, and a MSalkylene-oxide of 0.1 and does not have a combination of a DSmethyl of 2.5 or 2.0, a DSethyl of 0.1, and a MSalkylene-oxide of 0.05. The MEHEC has very good biostability and is suitable for use in the building industry.

Abstract: A fresh aqueous cement composition suitable for building purposes is described. It contains, besides a hydraulic cement, a methyl ethyl cellulose ether having a DS methyl of 0.4-2.2, a DS ethyl of 0.05-0.8 and a MS hydroxy-(C2-C3)-alkyl of 0-2. The celulose ether imparts excellent rheology properties, including a high water-retention combined with a long open time, to the cement composition. A dry blend and a rheology additive containing the cellulose ether are also described.

Abstract: A fresh aqueous cement composition suitable for building purposes is described. It contains, besides a hydraulic cement, a methyl ethyl cellulose ether having a DS methyl of 0.4-2.2, a DS ethyl of 0.050.8 and a MS hydroxy-(C2-C3)-alkyl of 0-2. The celulose ether imparts excellent rheology properties, including a high water-retention combined with a long open time, to the cement composition. A dry blend and a rheology additive containing the cellulose ether are also described.

Abstract: An aqueous concrete mixture having an air pore volume between 10 and 85%, preferably between 20 and 85%. When the aqueous concrete mixture is cured, a concrete having uniform density and high strength is obtained. This is achieved by including in the concrete mixture an aqueous, anionic surface-active compound containing two sulphonic acid groups of the general formula(R).sub.m --R.sub.1 --(SO.sub.3 M).sub.2 (1)wherein R is an aliphatic group having 4-20 carbon atoms, m is a number 1 or 2, the sum of the number of carbon atoms in the 1 or 2 R groups being 6-30, R.sub.1 is an aromatic group containing at least 2 aromatic rings and 10-20 carbon atoms, and M is a cation or hydrogen. The anionic compound has an air-entraining effect and improves the homogeneity of the concrete mixture.