聚羧酸减水剂在石膏基体系中的试验研究

关键字：聚羧酸减水剂,石膏,分散性,强度,结构分析

（苏州市兴邦化学建材有限公司，江苏 苏州  215155）

    摘要：研究了聚羧酸减水剂对纯石膏和石膏自流平砂浆分散性和强度的影响。采用醚类大单体合成了适用于石膏基体系的聚羧酸减水剂PC-3，并与2种市售石膏基专用减水剂PC-1、PC-2进行比较。结构分析表明，3种减水剂具有相似的分子结构，三者分子质量大小排序为PC-2>PC-1>PC-3，其中以PC-1的分子质量分布最宽，而PC-3的最窄。在纯石膏中，PC-1减水率最低，而PC-3在掺量为0.2%和0.3%时减水率分别达到19.9%和24.8%，分散性接近PC-2。在石膏自流平砂浆中，掺PC-3的自流平砂浆初始和30 min流动度均大于掺PC-1，略差于掺PC-2，而三者对砂浆强度影响差别不大。
    关键词：聚羧酸减水剂；石膏；分散性；强度；结构分析
    中图分类号：TU528.042.2           文献标识码：A         文章编号：1001-702X（2017）06-0113-04

Experimental study on gypsum-based system with polycarboxylic water reducer
YU Zhenxin，XU Ruyuan，TAO Juan
（Suzhou Sunbo Chemical Building Materials Co. Ltd.，Suzhou 215155，China）

    Abstract：Effects of the Polycarboxylate on dispersion and strength of pure gypsum and self-leveling mortar were investigated. Polycarboxylate（PC-3） was first synthesized and the comparison researches were done using two same kind of polycarboxylate（PC-1、PC-2） on sale. Structural analysis showed that three kinds of water reducer having a similar molecular structure，the order of the three molecular weight is PC-2>PC-1>PC-3，among which the PC-1 molecular weight distribution is the widest，and the PC-3 is the narrowest. In pure gypsum，the water reducing rate of PC-1 was lowest，which of PC-3 in content of 0.2% and 0.3% water rate reached 19.9% and 24.8%，respectively， dispersion close to PC-2. In the gypsum self-leveling mortar，the initial and 30 min fluidity of the PC-3 is better than PC-1，which is slightly worse than PC-2，but the difference is not significant among of which.
    Key words：polycarboxylic water reducer，gypsum，dispersion，strength，structure analysis