聚羧酸超塑化剂的制备及性能研究

Preparation and performance research of a polycarboxylate superplasticizer

为实现混凝土中水泥等材料的高效分散,以乙烯基丁基聚氧乙烯、丙烯酸等大单体为主要材料,添加金属氧化物助剂、烯丙基磺酸钠小分子单体以及H_(2)O_(2)引发剂等材料制备聚羧酸超塑化剂(VPCE)。从丙烯酸用量、引发剂成分、反应温度以及小分子单体种类等方面优化聚羧酸超塑化剂的制备方案。研究表明,VPCE的最优制备方案为:单体烯丙基磺酸钠、丙烯酸、乙烯基丁基聚氧乙烯的合理用量分别为2.50、9.88、90.00 g,最优引发体系为H_(2)O_(2)/ZnO,用量分别为1.50、0.01 g,最优反应温度为20℃,引发剂最佳滴加时间为45 min。最优方案制备的聚羧酸超塑化剂,水泥净浆的流动度可达到283 mm。

To achieve efficient dispersion of cement and other materials in concrete,polycarboxylate superplasticizer(VPCE)was prepared by using vinyl butyl polyoxyethylene,acrylic acid and other large monomers as the main materials,adding metal oxide additives,allyl sulfonic acid nano small molecule monomers,and H_(2)O_(2)initiator.The preparation scheme of polycarboxylate superplasticizer was optimized from the aspects of acrylic acid content,initiator composition,reaction temperature,and types of small molecule monomers.Through experimental research,it was found that the reasonable dosages of monomers sodium allylsulfonate,acrylic acid,and vinyl butyl polyoxyethylene alcohol ether are 2.50 g,9.88 g,and 90.00 g,respectively.The optimal initiator system is H_(2)O_(2)/ZnO(1.50 g/0.01 g).The optimal reaction temperature is 20℃,and the optimal drop time for initiator is 45 minutes.During the experiment,the flowability of the cement slurry can reach the highest level of 283 mm.