| 摘要 |
Water-retaining agents (I), pref. water-soluble cellulose ethers, e.g. Me-, Et-, hydroxyethyl-, benzyl-, or carboxymethyl cellulose or their alkali(ne earth) salts, and wetting agents, pref. anionactive, cationactive, amphoteric or non-ionogenic tensides, e.g. alkyl sulphates or sulphonates, alkylaryl or aryl sulphonates, or their alkali salts; fatty acid condensates, ethylene oxide adducts with fatty acids and alcohols, fatty alcohol sulphates, oil sulphates, alkylpolyglycol or alkylphenol ethers and/or polyphosphates, are present in building unit bonding compsns. contg mortar mixt. of binders, concrete aggregates and mixing water, esp. for assembly of light porous silicate concrete units. Pref. content of (I) and (II) depend on binder amt used, and pref. (II) content is less than (I) content. A pref. compsn. contains 5-25% cement, 70-90% SiO2, and 0.5-5% (I) and 0.1-1% (II) and necessary mixing water. Pref extrusion mortar contains a raised amt. binder, less aggregate and K2CO3. |
