水溶性纤维素醚减水剂合成与性能研究

Synthesis and Properties of Water-Soluble Cellulose Ether Based Concrete Water-Reducing Agent

采用棉纤维素制备平衡聚合度(levelling-off degree of polymerization,LODP)纤维素,以其为原料与氢氧化钠,1,4-丁基磺酸内酯(1,4-butanesultone,BS)反应,得到具有良好水溶性的丁基磺酸纤维素醚(sulfobutylated cellulose ether,SBC).研究了反应温度、反应时间以及原料配比等参数对丁基磺酸纤维素醚的影响,得出了最佳反应条件,并采用FTIR对产物进行了结构表征.通过研究SBC对水泥净浆和砂浆性能的影响,发现该产物具有与萘系减水剂相近的减水效果,且流动度保持性优于萘系减水剂;不同特性粘度以及硫含量的SBC对于水泥净浆具有不同程度的缓凝性.因此,SBC有望成为缓凝减水剂,缓凝高效减水剂,甚至高效减水剂.其性能主要由其分子结构决定.

Levelling-off degree of polymerization（LODP） cellulose was prepared, and then water- soluble sulfobutylated cellulose ether（SBC） was synthesized with the LODP cellulose, NaOH, and 1,4—butanesultone（BS）. The factors affecting the properties of SBC, such as the reaction time, the reaction temperature and mass fraction of reagents were studied, and the optimum condition for the product was obtained. The structure of SBC was characterized via FTIR spectra. The results of its application in cement paste and mortar suggest that SBC has some properties similar to sulfonated naphthalene-formaldehyde condensate（SNF） water-reducing agent, but the fluidity loss is less than the latter. And the setting time of cement paste adding SBCs was also tested. The results indicate that water-soluble SBCs have the potential to be developed as set-retarding and water-reducing agent, even high-range water-reducing agent. Their performances depend on the molecular structure of SBCs.