壳聚糖改性水硬石灰基复合胶凝材料的研究

Study on Modification of Hydraulic Lime Cementitious Composite Materials by Chitosan

以天然水硬性石灰(NHL),偏高岭土(MK)为主要原料,高分子壳聚糖为改性添加剂,进行了NHL-MK复合胶凝材料的制备与改性研究。采用XRD、SEM与力学性能万能试验机等测试方法,分析了壳聚糖对复合材料不同龄期力学性能及微观结构的影响。结果表明,壳聚糖的加入,促进了CaCO_(3)的生成,从而提高了胶凝材料早期的力学性能;壳聚糖自身的-OH和-NH_(2)与物料发生反应,改变了C-S-H的微观形貌,提高了材料的致密性,对胶凝复合材料的早期强度亦有贡献。

The preparation and modification of NHL-MK composite colloidal materials were studied by using natural hydraulic rigid lime(NHL),metakaolin(MK)as the main raw materials and polymer chitosan as the modification additive.The effects of chitosan on mechanical properties and microstructure of composites at different ages were analyzed by XRD,SEM and universal mechanical testing machine.The results showed that the addition of chitosan promoted the generation of CaCO_(3),thus improving the early mechanical properties of the cementing material.The reaction of-OH and-NH_(2)of chitosan with the material changed the microscopic morphology of C-S-H,improved the compactness of the material,and contributed to the early strength of the cementitious composite.