酸醚比对聚羧酸减水剂共聚物组成及性能影响

关键字：聚羧酸减水剂,酸醚比,共聚物组成,性能

（四川长安育才建材有限公司，四川 成都  610200）

    摘要：采用丙烯酸与醚类大单体TPEG-3000，通过自由基共聚制备系列不同酸醚比的聚羧酸减水剂，并通过GPC方法与水泥净浆及混凝土试验测试减水剂的组成和性能。结果表明：当酸醚比由3∶1增至8∶1时，减水剂的分子质量先增大后减小，分子质量分布变宽，而产物转化率受酸醚比的影响较小；当酸醚比为6∶1时，减水剂中锚固基团较多，吸附速率快，分散能力强，体系释放出较多的自由水，掺减水剂水泥水化速率较快，混凝土既具有较大的坍落度，也具有较高的早期强度。

    关键词：聚羧酸减水剂；酸醚比；共聚物组成；性能

    中图分类号：TU528.042.2   文献标识码：A  文章编号：1001-702X（2017）01-0094-03

 

Effect of acid/ether ratio on copolymer composition and performances of polycarboxylate superplasticizer

XIA Liangliang，NI Tao，LIU Zhaoyang，WANG Jinchun

（Sichuan ChangAn YuCai Building Materials Co. Ltd.，Chengdu 610200，China）

    Abstract：A series of polycarboxylate superplasticizers with different acid/ether ratio were prepared by free radical copolymerization between AA and TPEG-3000，and used GPC，cement paste and concrete experiments to explore composition and properties of superplasticizer. It was shown that superplasticizer molecular weight increased firstly and then decreased，molecular weight distribution turn into wide，while product yields had no obvious change when acid/ether ratio increased from 3∶1 to 8∶1. When the acid/ether ratio was 6∶1，the rate of adsorption of superplasticizer was fast result from major anchoring groups. And the product had stronger dispersing power which led to system release more free water and faster cement hydration speed，so the concrete not only had more slumps，but also had higher early strength.
  Key words：polycarboxylate superplasticizer，acid/ether ratio，copolymer composition，performance