CEMENT ADDITIVE COMPOSITION AND CEMENT COMPOSITION HAVING THE ADDITIVE COMPOSITION

摘要

PURPOSE: A cement additive composition is provided to improve water retention property and workability and to reduce water pocket and efflorescence by comprising cellulose ether, polyvinyl alcohol-based resin and redispersible powder resin. CONSTITUTION: A cement additive composition comprises cellulose ether, polyvinyl alcohol-based resin and redispersible powder resin. Cellulose ether includes at least one kind selected from the group consisting of methyl cellulose with the methyl substitution degree(DS) of 0.1~2.9, hydroxypropylmethylcellulose with the methyl substitution degree(DS) of 0.1~2.9 and the hydroxypropyl substitution degree(MS) of 0.01~2 hydroxyethylcellulose with the hydroxypropyl substitution degree(MS) of 0.1~10.0, ethylhydroxyethylcellulose with the ethyl substitution degree(DS) of 0.1~2.9 and the hydroxypropyl substitution degree(MS) of 0.01~2, and methylethylhydroxyethylcellulose with the methyl and ethyl substitution degree(DS) of 0.1~2.9 and the hydroxypropyl substitution degree(MS) of 0.01~2.