Relation Between Thermal Analysis, Phase Composition and Structure of Polyurethane Adhesives for Application in Wooden Structural Joints

Due to the possibility of damage from earthquakes, vibrations, humidity, and the degradation of wooden joints, there is growing interest in new polyurethane adhesives for wooden structures. These adhesives often have two or more purposes in such structures. Such purposes include connection strength, resistance to environmental conditions at the point of application, and behaviour during fire or under vibration. Some fundamental data on the application of materials exhibiting these properties concern their adhesive thermal stability. This paper focuses on the thermal stability of a new blend of flexible and rigid polyurethanes and its correlation with the structural properties of the material. The new polyurethanes were investigated using hot-stage microscopy for thermal stability of shape, and the results were correlated with DSC, thermogravimetry, and evolved-gas analyses. The experiments showed that it is essential to use primary research methods, including FTIR, XRD, DSC-TG-QMS, and HSM, to identify and characterise new polyurethane adhesives. These research methods are crucial for understanding the properties and potential applications of these materials and providing deeper insight into the subject. The tested polyurethane adhesives, new materials for construction, meet strict ecological requirements and are suitable for patching both small and large wooden structures, as well as for other construction applications, such as insulation and soundproofing.