甲基硅酸钠对脱硫石膏砌块耐水性能的影响  

Influence of Sodium Methyl Silicate on Waterproof Property of Desulfurized Gypsum Block

作　　者：何廷树[1] 亢泽千 陈畅[1] HE Tingshu;KANG Zeqian;CHEN Chang(College of Materials Science and Engineering,Xi'an University of Architecture and Technology,Xi'an 710055,China)

机构地区：[1]西安建筑科技大学材料科学与工程学院,陕西西安710055

出　　处：《建筑材料学报》2021年第2期247-253,259,共8页Journal of Building Materials

基　　金：省部共建西部绿色建筑国家重点实验室开放基金项目(LSKF201907);固体废物处理与资源化教育部重点实验室开放基金项目(18zxgk04);陕西省教育厅基金(18JK0469);陕西省教育厅重点实验室科研计划项目(19JS044)。

摘　　要：采用扫描电镜、红外光谱分析等手段,研究了甲基硅酸钠掺量对脱硫石膏砌块耐水性能的影响.结果表明:当甲基硅酸钠掺量为0.2%~1.4%时,随着掺量的增大,脱硫石膏砌块强度先增后减,表面接触角不断增大,吸水率不断降低,软化系数稳定增长;与纯脱硫石膏砌块相比,甲基硅酸钠掺量为1.0%的脱硫石膏砌块强度变化不大,但吸水率降至7%、软化系数达到0.85;甲基硅酸钠在砌块表面和孔壁形成的疏水性薄膜导致砌块吸水率降低、软化系数提高;掺入甲基硅酸钠会改变二水石膏晶体形貌和脱硫石膏砌块的微观结构,从而影响砌块强度.The effect of sodium methyl silicate content on the water resistance of desulfurization gypsum block was studied by means of scanning electron microscopy(SEM)and Fourier transform infrared spectroscopy(FTIR).The results show that the strength of desulfurized gypsum block increases first and then decreases when the content of sodium methyl silicate is 0.2%1.4%.The surface contact angle is increased,water absorption is greatly reduced,and softening coefficient increased steadily.When the content of sodium methyl silicate is 1.0%,the water absorption of desulfurized gypsum block is 7%;the softening coefficient is 0.85.Compared with the control sample,the flexural and compressive strength values have no significant change.FTIR spectral analysis show that sodium methyl silicate can form hydrophobic film on the surface and pore wall of block,which is the main reason for the decrease of water absorption and the improvement of softening coefficient of block.The addition of methyl silicate will change the crystal morphology and microstructure of dihydrate gypsum,thus affecting the strength of the block.

关 键 词：甲基硅酸钠 石膏砌块 耐水性能 力学性能 微观形貌 

分 类 号：TQ177.3[化学工程—硅酸盐工业]