基于高分子量聚醚大单体常温合成聚羧酸减水剂试验研究

Room temperature synthesis based on high molecular weight polyether macromonomer experimental study on polycarboxylate superplasticizer

采用分子量为3000的甲基烯丙基聚氧乙烯醚(HPEG)为合成聚醚大单体,分别研究了酸谜比、合成起始温度及链转移剂用量对聚羧酸减水剂性能的影响。通过净浆流动度、混凝土坍落度以及扩展度为指标进行测试,结果表明,当设计体系酸谜比为4.35,合成温度区间为15~25℃,链转移剂用量为单体总量的1.75%,H_(2)O_(2)用量为单体总质量的0.8%时合成样品性能较好,HPEG3000合成聚羧酸减水剂初始分散性及保持能力较强,对比HPEG2400合成的聚羧酸减水剂有明显性能优势。

Methyl allyl polyoxyethylene ether(HPEG) with molecular weight of 3 000 was used to synthesize polyether macromonomer.The effects of acid ratio,synthesis starting temperature and the amount of chain transfer agent on the properties of polycarboxylate water reducer were studied.Tested by the fluidity of slurry,slump and expansion of concrete as indicators,the results show that when the acid-enrichment ratio of the design system is 4.35,the synthesis temperature range is 15~25 ℃,and the amount of chain transfer agent is 1.75% of the total monomers,when the amount of H_(2)O_(2)is 0.8% of the total monomer mass,the performance of the synthesized sample is better.The initial dispersibility and retention capacity of the HPEG3000 synthetic polycarboxylate water reducer are stronger,and the polycarboxylate water reducer synthesized by HPEG2400 has obvious performance advantages.