Abstract This work focuses on the comparison between the mechanical and microstructural properties of poly(sialate-siloxo) networks based on metakaolins from halloysite and kaolin. Poly(sialate-siloxo) networks were prepared using three metakaolins as aluminosilicate sources. Sodium waterglass from rice husk ash and commercial sodium waterglass were used as chemical reagents. The obtained results showed that metakaolins from kaolins have plate shapes with coarse particle sizes whereas the one from halloysite has a spherical morphology and smaller particle sizes. The IR spectra of poly(sialate-siloxo) networks from calcined halloysite indicate the higher value of the wavenumber of the main band. The XRD patterns of all poly(sialate-siloxo) networks show the broad hump structure with higher intensity between 18 and 40°(2θ). The XRD patterns of poly(sialate-siloxo) networks show the band of the unreacted metakaolin at about 20.45°(2θ). This band is more pronounced on the XRD patterns of geopolymer cements from calcined halloysite. The obtained poly(sialate-siloxo) networks based on metakaolins from halloysite and kaolin have a compact, homogenous and denser microstructures. The compressive strength values of the poly(sialate-siloxo) networks using calcined kaolin are ranging from 58.43 to 66.52 MPa whereas those using calcined halloysite are between 72.29 and 88.50 MPa. The compressive strength values of poly(sialate-siloxo) networks using calcined halloysite are higher compared to those from calcined kaolin. The higher compressive strength values of the geopolymer cements from calcined halloysite could be attributed to the fine and spherical particle sizes of calcined halloysite. This implies that the shape and the fine particle sizes of the raw materials influence the properties of the poly(sialate-siloxo) networks. Metakaolin from halloysite can be used as an aluminosilicate source for producing poly(sialate-siloxo) network with higher mechanical properties.

中文翻译：

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使用来自高岭土和埃洛石的偏高岭土作为铝硅酸盐来源获得的聚（唾液酸 - 硅氧烷）网络的微观结构和机械性能：比较研究

摘要 这项工作的重点是比较基于埃洛石和高岭土偏高岭土的聚（唾液酸-硅氧烷）网络的机械和微观结构特性。使用三种偏高岭土作为铝硅酸盐来源制备聚（唾液酸-硅氧烷）网络。来自稻壳灰的钠水玻璃和商业钠水玻璃用作化学试剂。所得结果表明，来自高岭土的偏高岭土具有颗粒粗大的板状，而来自埃洛石的偏高岭土具有球形形态和较小的颗粒尺寸。来自煅烧埃洛石的聚（唾液酸-硅氧烷）网络的红外光谱表明主带的波数值较高。所有聚（唾液酸 - siloxo）网络的 XRD 图案显示出宽的驼峰结构，在 18 到 40°（2θ）之间具有更高的强度。聚（唾液酸-硅氧烷）网络的 XRD 图案显示未反应的偏高岭土在约 20.45°（2θ）处的带。该带在来自煅烧埃洛石的地质聚合物水泥的 XRD 图案上更为明显。获得的基于来自埃洛石和高岭土的偏高岭土的聚（唾液酸-硅氧烷）网络具有紧凑、均匀和致密的微观结构。使用煅烧高岭土的聚（唾液酸-硅氧烷）网络的抗压强度值为 58.43 至 66.52 MPa，而使用煅烧埃洛石的则为 72.29 至 88.50 MPa。与来自煅烧高岭土的那些相比，使用煅烧埃洛石的聚（唾液酸-硅氧烷）网络的抗压强度值更高。来自煅烧埃洛石的地质聚合物水泥具有较高的抗压强度值可归因于煅烧埃洛石的细小球形颗粒尺寸。这意味着原材料的形状和细粒度会影响聚（唾液酸-硅氧烷）网络的性能。来自埃洛石的偏高岭土可用作生产具有更高机械性能的聚（唾液酸-硅氧烷）网络的铝硅酸盐来源。