1. The Effect of the Performance of Silicone Structural Adhesive on the Durability of Buildings
The performance and lifespan of silicone structural adhesives have been a long-standing topic of concern in the industry, with manufacturers, construction units, direct users, and designers paying close attention. A small adhesive strip is like a sewing thread, which elastically connects building fasteners and also bears corresponding forces. Like sewing thread, the amount and cost of this material are not significant, but its role is crucial. Due to the fact that most of the main materials in buildings are inorganic, the durability of these main materials is generally guaranteed. However, silicone structural adhesive belongs to organic materials and its durability is not as good as inorganic materials. Therefore, silicone structural adhesive should be a controlling and restrictive material that affects the service life and structural safety of curtain wall buildings.
2. Comparative Analysis of the Advantages and Disadvantages of Silicone Adhesive
Silicone adhesive contains both organic groups and inorganic Si-O structure, which combines the properties of inorganic and organic materials, especially in terms of excellent UV resistance, heat resistance, and aging resistance. Therefore, it is a material that can undergo historical testing for building curtain walls. It has been applied for more than 40 years abroad and 30 years in China. However, silicone structural adhesives are not as good as C-C polymer compounds in terms of acid and alkali resistance, hydrolysis resistance, and chemical inertness. So in the presence of substances such as acids, alkalis, metal catalysts, and water vapor (especially silicon products with high water vapor transmittance), silicone structural sealants may undergo chemical reactions, leading to aging and performance degradation.
3. Analysis of Structural Adhesive Bonding Performance
The evaluation of the adhesive performance of structural adhesives involves two important indicators - adhesive failure area and adhesive strength. The adhesive strength and durability of structural adhesives must be adequately guaranteed. There are some typical manifestations of non bonding. If the adhesive strip is peeled off without too much force, and the peeling surface appears very smooth, there are not many residual adhesive blocks. In most cases, the tensile strength is also sufficient, but the bonding failure area will exceed the standard. There is no universal adhesive to solve the bonding problem. The current situation in the industry is as follows: standard materials such as glass have excellent bonding performance, Standard anodized aluminum profiles Bonding is also guaranteed. However, for new types of surface treated materials, the bonding conditions cannot guarantee complete stability. Therefore, the current common method is to apply targeted primer on the bonding surface, which has been proven to be a useful solution for a long time. Another advantage of primer is to improve the bonding condition at the interface and avoid adding too many harmful substances to the entire colloid. In the selection of new materials Both appearance and safety should be taken into account, especially in terms of safety. The construction unit should fully understand and cooperate, clean the surface, and maintain the construction.
4. Overview of Aging Performance of Structural Adhesive
Here involves a keyword: chemical aging, physical aging is one aspect, and chemical aging is more central. The main manifestation of aging is a significant deterioration in properties such as adhesion and tensile strength, elongation at break, and elastic recovery rate. In severe cases, the colloid will become very hard and lose its elasticity. The manifestations of aging also have initial and long-term effects. During the initial aging and degradation process of polymers, the core cross-linking points undergo degradation first, which leads to the degradation of the adhesive