Pontinha Ana Dora Rodrigues, Mäntyneva Johanna, Santos Paulo, Durães Luísa
University of Coimbra, CIEPQPF, Department of Chemical Engineering, 3004-531 Coimbra, Portugal.
Häme University of Applied Sciences, HAMK Tech Research Unit, 13100 Hämeenlinna, Finland.
Gels. 2023 Mar 18;9(3):241. doi: 10.3390/gels9030241.
The reliable characterization of insulation materials in relevant environmental conditions is crucial, since it strongly influences the performance (e.g., thermal) of building elements. In fact, their properties may vary with the moisture content, temperature, ageing degradation, etc. Therefore, in this work, the thermomechanical behaviour of different materials was compared when subjected to accelerated ageing. Insulation materials that use recycled rubber in their composition were studied, along with others for comparison: heat-pressed rubber, rubber_cork composites, aerogel_rubber composite (developed by the authors), silica aerogel, and extruded polystyrene. The ageing cycles comprised dry-heat, humid-heat, and cold conditions as the stages, during cycles of 3 and 6 weeks. The materials' properties after ageing were compared with the initial values. Aerogel-based materials showed superinsulation behaviour and good flexibility due to their very high porosity and reinforcement with fibres. Extruded polystyrene also had a low thermal conductivity but exhibited permanent deformation under compression. In general, the ageing conditions led to a very slight increase in the thermal conductivity, which vanished after drying of the samples in an oven, and to a decrease in Young's moduli.
在相关环境条件下对绝缘材料进行可靠表征至关重要，因为这会强烈影响建筑构件的性能（如热性能）。事实上，它们的性能可能会随含水量、温度、老化降解等因素而变化。因此，在本研究中，比较了不同材料在加速老化时的热机械行为。研究了在其组成中使用再生橡胶的绝缘材料，以及其他用于比较的材料：热压橡胶、橡胶软木复合材料、气凝胶 - 橡胶复合材料（由作者开发）、二氧化硅气凝胶和挤塑聚苯乙烯。老化循环包括干热、湿热和寒冷条件作为阶段，循环周期为3周和6周。将老化后材料的性能与初始值进行了比较。气凝胶基材料由于其非常高的孔隙率和纤维增强而表现出超级绝缘行为和良好的柔韧性。挤塑聚苯乙烯也具有低导热率，但在压缩下会出现永久变形。一般来说，老化条件导致热导率略有增加，在烘箱中干燥样品后这种增加消失，并且杨氏模量降低。
