Ślosarczyk Agnieszka, Vashchuk Andrii, Klapiszewski Łukasz
Institute of Building Engineering, Faculty of Civil and Transport Engineering, Poznan University of Technology, Piotrowo 3, PL-60965 Poznan, Poland.
Institute of Chemical Technology and Engineering, Faculty of Chemical Technology, Poznan University of Technology, Berdychowo 4, PL-60965 Poznan, Poland.
Polymers (Basel). 2022 Apr 2;14(7):1456. doi: 10.3390/polym14071456.
This paper presents an analysis of research results for silica aerogel cement composites over the past twenty years. Recently, two trends in the development of these composites have been noted, towards structural applications and towards ultralight composites for coatings and renders. Ongoing research shows that important aspects of cementitious composites with good mechanical performance are the proper selection of aggregates and improved adhesion at the silica aerogel-cement binder interface, which will guarantee high compressive strength with the lowest possible thermal conductivity. The best physicomechanical performance of aerogel cement composites with low thermal conductivity below 0.03 W/(m·K) was obtained when cenospheres and aerogel were used in a weight percentage of 5%. In turn, the prerequisites for using aerogel cement composites as coatings for energy-efficient building façades are the use of large amounts of silica aerogel as a substitute for lightweight aggregates or the selection of an optimal composition of lightweight aggregates and aerogel, ensuring the lowest possible thermal conductivity coefficient. Other important standpoints are water transport and moisture protection of the silica aerogel-based coatings. Therefore, in recent years, more and more elements of the hygrothermal performance, porosity and durability of silica aerogel cement composites have been developed. The article also points out the weaknesses of the application of silica aerogel in the cement matrix, the most important of which are the lack of adhesion at the boundary of the aerogel-cement binder, the increased porosity of the composite, the high water absorption capacity and the significant decrease in compressive strength with large volumes of silica aerogel. Solving these issues will certainly contribute to the wider applicability of these materials in the construction industry.
本文对过去二十年中二氧化硅气凝胶水泥复合材料的研究成果进行了分析。最近，人们注意到这些复合材料发展的两个趋势，即朝着结构应用方向以及朝着用于涂料和抹灰的超轻复合材料方向发展。正在进行的研究表明，具有良好力学性能的水泥基复合材料的重要方面是骨料的正确选择以及二氧化硅气凝胶 - 水泥粘结剂界面处附着力的提高，这将确保在尽可能低的热导率下具有高抗压强度。当空心微珠和气凝胶的重量百分比为5%时，可获得热导率低于0.03W/(m·K)的气凝胶水泥复合材料的最佳物理力学性能。反过来，将气凝胶水泥复合材料用作节能建筑外墙涂料的前提条件是使用大量二氧化硅气凝胶替代轻质骨料，或者选择轻质骨料和气凝胶的最佳组成，以确保尽可能低的导热系数。其他重要观点是基于二氧化硅气凝胶的涂料的水分传输和防潮性能。因此，近年来，对二氧化硅气凝胶水泥复合材料的湿热性能、孔隙率和耐久性的研究越来越多。文章还指出了二氧化硅气凝胶在水泥基体中应用的弱点，其中最重要的是气凝胶 - 水泥粘结剂边界处缺乏附着力、复合材料孔隙率增加、高吸水能力以及大量二氧化硅气凝胶导致抗压强度显著降低。解决这些问题肯定会有助于这些材料在建筑行业中更广泛的应用。
