聚羧酸减水剂增强陶瓷模具石膏性能机理研究  

Improvement of Performance of Model-Gypsum by Polycarboxylate-Type Water Reducer and Its Mechanism

作　　者：赵敏[1] 彭家惠[1,2] 张明涛[1] 李志新[1] 朱登玲[1] 

机构地区：[1]重庆大学材料科学与工程学院,重庆400030 [2]重庆建大建材有限公司,重庆400030

出　　处：《建筑材料学报》2015年第2期255-262,共8页Journal of Building Materials

基　　金：国家自然科学基金资助项目(50872160)

摘　　要：系统研究了聚羧酸减水剂(PC)对陶瓷模具石膏工作性能、强度、吸水及耐溶蚀性能的影响,并采用电导率、水化温升、SEM形貌分析及BET孔结构测试方法进行机理研究.结果表明:陶瓷模具石膏减水率(质量分数)随PC掺量(质量分数)增加而逐渐增加,掺0.30%PC时,陶瓷模具石膏减水率高达18.7%;陶瓷模具石膏浆体流动度经时损失明显降低,有效工作时间延长4min,凝结时间稍有延缓;PC对提高陶瓷模具石膏强度及耐溶蚀效果显著,掺0.30%PC时,其抗折、抗压强度分别为4.38,15.9MPa,增幅高达22%,57%,溶蚀率(质量分数)由-0.93%降至-0.15%,降幅达16.1%;掺入PC可降低陶瓷模具石膏的吸水性能;PC在石膏颗粒表面的吸附可延缓石膏的水化进程,使二水石膏晶体细化,长径比增加,晶体搭接密实度提高,可降低硬化体孔隙率、细化孔径,有效提高石膏抵抗浆体电解侵蚀破坏的能力.The effects of polycarboxylate-type water reducer（PC） on working performance, strength, wa- ter absorption and corrosion rate of model-gypsum were presented. The mechanism was analyzed by meas- urement of electric conductivity, the temperature rise of hydration, SEM and BET. The result shows that PC content of 0.30% （by mass） had a high reduction rate of 18.7% （by mass） to improve the workability of gypsum which made the working time extended for 4 rain and the setting time lengthened slightly. The strength and corrosion properties of gypsum were significantly increased. Flexural strength and compres- sive strength were improved by 22% and 57% at 0. 30% of PC content, and the corrosion rate decreased from-0. 93% to-0. 15%. Water absorption anisms show that the adsorption on the surface rate decreased with the increase of PC content. The mech- of gypsum is the base for PC to the function. The hydra- tion process of gypsum delayed to some extent. The dimension of dehydrate crystal is fined. The amount of pore in gypsum is lessened and the sizes become smaller. The corrosion was remarkably diminished.

关 键 词：聚羧酸减水剂 陶瓷模具石膏 性能影响 水化进程 晶体形貌 孔结构 

分 类 号：TQ177.3[化学工程—硅酸盐工业]