微波作用下β-环糊精改性酰胺型聚羧酸减水剂的制备及性能研究

发布时间：2018-07-16 23:28

【摘要】：β-环糊精为大体积立体空腔构型,兼具外缘亲水、内腔疏水特性,经马来酸酐酯化改性后,结合酰胺型聚羧酸减水剂高性能优势,采用微波辐射技术制备出含β-环糊精侧基的酰胺型聚羧酸减水剂。通过水泥净浆流动度测试表明,在pH值7~11之间β-环糊精改性酰胺型聚羧酸减水剂(MPC)具有较好的耐碱性质;与无β-环糊精侧基的酰胺型聚羧酸减水剂相比,MPC在水泥颗粒表面吸附性强,当掺量为4 g/L时,体系Zeta电位绝对值达41.2 mV,具有较好的静电斥力效应,产品分散性能良好,且减水剂掺量0.5%时,砂浆减水率为34.3%;经MPC性能测试表明,β-环糊精改性酰胺型聚羧酸减水剂兼有缓凝和高效减水效能,与空白样相比,掺量0.3%、0.5%对应的7、28 d抗压强度分别增强了24.6%、37.2%、30.5%、31.4%,说明减水剂对水泥试块后期强度增强显著;并借助红外光谱和扫描电镜技术,依据减水剂分子构效原理,探究了减水剂相关作用机理,以为后期高性能聚羧酸减水剂的开发提供理论基础。
[Abstract]:尾 -cyclodextrin is a large volume three-dimensional cavity configuration with hydrophilic and hydrophobic properties of inner cavity. After esterification with maleic anhydride, 尾 -cyclodextrin is combined with the high performance superiority of amide type polycarboxylic acid water reducer. An amide-type polycarboxylic acid superplasticizer containing 尾-cyclodextrin side group was prepared by microwave radiation. The fluidity test of cement paste shows that 尾 -cyclodextrin modified amide polycarboxylic acid water reducer (MPC) has good alkali resistance between pH 7 and 11. Compared with amide-type polycarboxylic acid superplasticizer without 尾 -cyclodextrin side group, MPC adsorbs strongly on the surface of cement particles. When the dosage is 4 g / L, the absolute value of Zeta potential of the system reaches 41.2 MV, which has good electrostatic repulsion effect and good dispersion performance. The water reducing rate of mortar was 34.3when the water reducing agent was 0.5%, and the MPC performance test showed that 尾 -cyclodextrin modified amide polycarboxylic acid water-reducing agent had both retarding and high water-reducing efficiency, compared with blank sample. The compressive strength of 728 days corresponding to 0.33% and 0.5% of the amount of water reducer was increased by 24.6% and 30.5% and 31.4 respectively, indicating that the later strength of water reducer to cement test block was significantly enhanced, and the mechanism of water-reducing agent related to water reducer was explored by means of infrared spectroscopy and scanning electron microscope. It provides a theoretical basis for the development of high performance polycarboxylic acid superplasticizer.
【作者单位】：广西科技大学生物与化学工程学院;广西科技大学广西糖资源绿色加工重点实验室;广西科技大学广西高校糖资源加工重点实验室;广西科技大学鹿山学院;
【基金】：国家自然科学基金项目(31560466) 广西教育厅科研项目(KY2015YB170)
【分类号】：TU528.042.2

【相似文献】