| 摘要 |
To a cement composition there is added an alkylene oxide adduct having the general formula <CHEM> where R1 is the group CH2NR4R5 or the group C2N<+>R4R5R6X<->, where R4, R5 and R6 are alkyl or hydroxyalkyl groups having 1-4 carbon atoms and X is an anion, R2 is an alkyl group having 1-15 carbon atoms, R3 is hydrogen or one of the groups R2 and R1, n1 is a number between 10 and 200, preferably 25-100, n2 is a number between 0 and 100, preferably 0-25, the total number of carbon atoms in the alkyl substituents in the benzene ring being 6-30 and the ratio between n1 and n2 more than 2. In this way the cement based composition obtains a good fluidity and an appropriate air content. |
