Hu Yuan, Jin Zuquan, Pang Bo, Du Zhantao, Li Xiangxiang, Huang Yuxin
Department of Civil Engineering, Qingdao University of Technology, Qingdao 266520, China.
Engineering Research Center of Concrete Technology under Marine Environment, Ministry of Education, Qingdao 266520, China.
Materials (Basel). 2024 May 23;17(11):2516. doi: 10.3390/ma17112516.
The reduction in the rheological parameters and dissolution rate of precursors in geopolymer coatings during early hydration significantly contributes to sagging. This study aims to improve the sag resistance of these coatings by incorporating diatomite filler. Rheological testing was conducted to assess the impact of diatomite and its concentration on the yield stress, plastic viscosity, and thixotropy of the geopolymer coatings. The results indicated that diatomite's large specific surface area and high reactivity have a significant influence on the rheological parameters and early dissolution rate of precursors. With a diatomite concentration of 1.1%, the coating exhibited a yield stress of 2.749 Pa and a plastic viscosity of 0.921 Pa·s, maintaining stability, homogeneity, and no sagging at a thickness of 600 μm. Furthermore, the highly active SiO in diatomite participates in the secondary hydration reaction of the geopolymer materials led to the formation of substantial C-(A)-S-H gel. This gel enhances internal interconnectivity within the coating, thereby improving its rheological and mechanical properties.
在早期水化过程中，地质聚合物涂层中前驱体的流变参数和溶解速率降低是导致流挂现象的重要原因。本研究旨在通过添加硅藻土填料来提高这些涂层的抗流挂性能。通过流变学测试评估了硅藻土及其浓度对地质聚合物涂层屈服应力、塑性粘度和触变性的影响。结果表明，硅藻土的大比表面积和高反应活性对前驱体的流变参数和早期溶解速率有显著影响。当硅藻土浓度为1.1%时，涂层的屈服应力为2.749 Pa，塑性粘度为0.921 Pa·s，在600μm厚度下保持稳定、均匀且无流挂现象。此外，硅藻土中高活性的SiO参与地质聚合物材料的二次水化反应，导致大量C-(A)-S-H凝胶的形成。这种凝胶增强了涂层内部的互连性，从而改善了其流变和力学性能。
