改性草浆碱木素减水剂

In order to use straw pulp lignin to produce water reducer of concrete, the solicitation oxidation, sulphonation processing and technical parameters for preparation chemical modified straw pulp lignin plasticizer (MLP) were investigated, and the characteristics of MLP were evaluated by measuring its IR spectrum, adsorbed amount on cement grains, zeta potential of cement and surface tension of MLP water solution. In addition, the properties of concrete plasticized with MLP were tested. Experimental results indicate that a kind of lignosulphonate, which has a water reducing rate of 15.2%, with —OH and —SO3 groups, can be obtained by oxidation and sulphonating straw pulp lignin, and that MLP has better adsorption-dispersion ability to cement grains by electrostatic repulsion. MLP may reduce surface tension of water. The properties of concrete plasticized with MLP accord with Chinese standard. As a kind of high range water reducer, MLP may replace lignosulphonates and partially replace naphthalene sulphonated formaldehyde condensates to be used in concrete.