摘要
为研究开发强度高、耐腐蚀性好的保温建筑材料,以节省建筑能源消耗,拓宽秸秆工业化利用途径,该文将秸秆掺入到土壤聚合物中制备秸秆土聚物,以抗压强度为指标,优选秸秆土聚物的较优工艺,并测定了秸秆土聚物的导热系数,确定其保温性能。用X射线衍射、傅立叶红外光谱以及扫描电镜对秸秆土聚物复合材料的晶相成分、化学键合和微观结构进行了分析。结果表明秸秆土聚物较优工艺配方如下:反应体系中Si O2与Al2O3摩尔比为3.9,Na2O与Si O2摩尔比为0.30,秸秆掺量4%,长度1 mm,水灰比0.10,制备得到的试块置于(20±2)℃、相对湿度为70%±2%的环境中养护,其7 d抗压强度可达54.58 MPa,导热系数为0.0681 W/(m·K)。X射线衍射、傅立叶红外光谱以及扫描电镜分析表明秸秆土壤聚合物为Si,O,Al组成的半晶态,无定形层状结构,与纯土聚物红外特征峰相同,无新化学键生成。秸秆土聚物界面处出现间隙和裂纹,裂纹遇秸秆后转向,产生二次裂纹,形成弱结合界面。初步判断秸秆与土聚物之间没有发生化学结合。研究结果为秸秆的工业资源化利用开辟了一条新途径,也为绿色保温建筑材料的研究提供依据。
In order to develop a new insulation building material with high strength and better corrosion resistance, straws were added into geopolymer to synthesis straw-reinforced geopolymer composites, which can save building energy consumption and broaden industrial utilization way of straw because of its good thermal insulation and light weight properties. The composites also overcome the defects of low strength in traditional straw building materials. In this paper, modulus of the sodium silicate mixed with Na OH as alkaline activator was 3, and straws were cut to specific lengths after drying. After a certain amount of distilled water and alkaline activator added, the reaction was carried out in a cement paste mixer with constant stirring. When the geopolymer turned to be slurry, it was moulded into 20 mm×20 mm×20 mm cubes for 24 hours. Then the demolded straw-geopolymer would be placed into a humidity chamber and tested for compressive strength using TYE-300 B Pressure Testing Machine when the schedule maintenance completed. The experiments which aimed to study the effect of A（molar ratio of Si O2 and Al2O3 in the reaction system）, B（molar ratio of Na2 O and Si O2 in the reaction system）value on the compressive strength of straw-geopolymer were carried out by adopting the matrix design. Besides, the effects of straw length（1-10mm）, straw content（1%-10%）, water-metakaolin ratio（0.09 、 0.10 、 0.11 、 0.12） and relative humidity（50%-90%）were studied under the best values of A and B. Process of straw-reinforced geopolymer was optimized based on compressive strength. The thermal conductivity was also measured to ensure the thermal insulation property. The eutectic phase, chemical bonding and microstructure were analyzed by XRD, SEM and FT-IR. Results showed that the better formula of straw-geopolymer was that molar ratios of SiO2 and Al2O3, and of Na2 O and SiO2 were 3.9 and 0.30, respectively. The mixed straw accounted for 4% with the length of 1 mm, and the ratio of water and metakaolin w
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2015年第4期332-338,共7页
Transactions of the Chinese Society of Agricultural Engineering
基金
浙江省自然科学基金(Y4090575)
关键词
秸秆
绝缘
界面
土壤聚合物
工艺
straw
insulation
interfaces
geopolymer
process
