摘要
使用3种聚合物乳液(SD-800改性苯丙乳液、SD-528硅丙乳液、SD-5681氟硅乳液)对稻秆进行表面成膜处理,比较研究了原稻秆与成膜处理后稻秆吸水速率、稻秆水泥胶砂试样力学强度和稻秆水泥混合物水化热的变化,并通过差热分析、X射线衍射分析、扫描电镜分析等研究了稻杆水泥混合物及胶砂试样水化程度的变化.结果表明:与原稻秆相比,成膜处理可有效降低稻杆的吸水性,促进稻杆水泥混合物的水化,从而提高了硬化水泥浆体的力学强度;稻杆以固含量(质量分数)50%SD-800改性苯丙乳液成膜2次的效果最佳,其5 min吸水速率降低了9.8 g/(g.h),24 h吸水速率是原稻杆的0.686倍,相应胶砂强度则较原稻杆提高了12.6 MPa,水化最高温度比原稻杆水泥混合物提高了10.4℃,到达最高温度的时间提前了300 min,抑制系数降低了44.8%;稻杆水泥混合物水化1 d后C-S-H,Ca(OH)2的放热峰面积增加,Ca(OH)2的峰值增强.
Surface of rice straw was modified by three kinds of polymer emulsions,the water absorption of original straw and treated straw,the mechanical strength and the hydration heat of the rice straw and cement mixture were analyzed by thermogravimety-differential scanning calorimeter（TG-DSC）,X-ray diffraction（XRD）,SEM,etc.The results show that film-forming treatment can effectively restrained the absorbed water content of rice straw,promote the hydration of straw cement mixture,thereby increase the mechanical strength of hardened cement paste compared with the original rice straw.The results also show that surface of rice straw coated two times with modified styrene-acrylic emulsion has the best result,the water absorption rate is reduced by 9.8 g/（g·h） in 5 min,its 24 h water absorption rate is only 0.686 times that of the original rice straw,28 d compressive strength of hardened mortar increases by 12.6 MPa,the hydration maximum temperature of mixture paste of rice straw with cement increases by 10.4 ℃,the time to the highest temperature reduces by 300 min,inhibition coefficient reduces by 44.8%.The TG-DSC analysis shows that exothermic peak area of C-S-H,Ca（OH）2 increases,Ca（OH）2 peak intensity in XRD is increased.
出处
《建筑材料学报》
EI
CAS
CSCD
北大核心
2010年第3期402-408,共7页
Journal of Building Materials
基金
江苏省科技支撑计划项目(BE2008653)
江苏省科技厅自然科学基金资助项目(BK2008574)
关键词
聚合物乳液
稻杆
水泥
成膜处理
polymer emulsion
rice straw
cement
film processing
