The aesthetic beauty of glass curtain walls has garnered widespread ‘wow’ reactions and has become the prevailing trend in modern architecture. Along with this, there is a growing demand for enhanced waterproofing, sealing, and energy-saving performance. Silicone sealant offers key advantages, such as resistance to aging, waterproofing, UV protection, high-temperature tolerance, excellent flexibility, and strong adhesion. But how does high-quality silicone sealant optimize energy savings in glass curtain walls? WD Sealant will address this in detail.
Architectural curtain wall is widely used in some large-scale public buildings or modern commercial buildings, and the commonly used curtain wall structures include glass, slate, composite aluminum panels and so on. Glass curtain walls can create a sense of lightness and spaciousness, enhance natural lighting in buildings, and establish a seamless connection between the interior and exterior environments, creating a transparent and comfortable space. It is a typical structure of curtain walls.
The benefits of Using Glass Curtain Wall
Glass curtain walls are made by combining mirror glass with ordinary glass, and the gap is filled with dry air or inert gases to form insulating glass. Insulating glass can be either double-glazed or triple-glazed. Double-glazed insulating glass consists of two layers of glass with a sealed frame, creating an interlayer space, while triple-glazed glass consists of three layers of glass, forming two interlayer spaces. Insulating glass offers several advantages, including sound insulation, heat insulation, frost prevention, moisture resistance, increased daylighting, and high wind pressure resistance.
The Shortcomings of Using Glass Curtain Walls
The widespread use of curtain wall structures relies heavily on silicone structural sealants, which is made from organic silicon materials, are essential for bonding glass curtain walls. However, since the sealants are exposed to external environments for extended periods, they are vulnerable to the effects of atmospheric conditions, rain, snow, and high temperatures. If the quality of the sealant is compromised, it can negatively impact the bond strength of the curtain wall structure, reducing its waterproofing and sealing effectiveness. This can lead to leaks at the joints, especially when pressure differences exist between the interior and exterior of the wall, making it easier for moisture to seep through the gaps. The infiltration of rainwater not only affects the indoor comfort of living and working spaces but can also damage interior finishes. In severe cases, it may even cause safety hazards, such as the detachment of curtain wall panels. Additionally, the extensive use of glass panels in curtain wall construction can weaken energy efficiency, further contributing to building energy consumption.
How High-Quality Silicone Sealant Can Help?
Silicone sealant offers numerous performance advantages. In terms of weather resistance, it has excellent durability against weathering, UV radiation, water, and ozone. Its performance does not degrade under prolonged exposure to water and ultraviolet light. It has outstanding performance in both high and low temperatures. At temperatures as low as -40°C, it will not become hard or brittle, and at high temperatures of up to 150°C, it will not become sticky or degrade. Additionally, it offers excellent electrical insulation properties and strong adhesion to most building materials.
High-quality weather-resistant sealant ensures that the joints maintain long-term water and air tightness. It prevents leakage from affecting the adhesive strength of the structural sealant and causing corrosion to internal metal components, and also prevents air leakage from compromising the building’s insulation performance.
How to Choose High-Quality Structural Sealant?
High temperatures significantly impact the aging of silicone structural sealant. When the sealant temperature reaches 90°C, the silicon-oxygen bonds in the gel structure undergo hydrolysis, causing the gel to soften and reducing its adhesive performance. This can lead to issues such as cracking and peeling. When selecting a product, it is essential to consider whether the sealant contains white oil. While silicone-based polymers are more expensive, they offer superior quality compared to white oil, which is a cheaper filler. The cost of sealants with white oil can be reduced to about 60% of the cost of unfilled sealant. However, after using low-quality filled sealants for several months to half a year, the mineral oil used as a filler begins to migrate and seep out. This results in the sealant becoming hard, cracked, powdery, oily, and losing adhesion, leading to a range of issues that not only affect the quality but also pose serious safety risks to the user.
Key Factors in High-Quality Silicone Sealant: Adhesion, Compatibility, and Contamination
Different substrates require different sealants. For each batch of products, WD Sealant tests the compatibility, adhesion, and potential contamination of silicone sealant with the materials it comes into contact with, and records the performance data of the sealant with different materials.
- Adhesion: Silicone sealant needs to form a strong bond with glass, metal, and other construction materials. If the adhesion is insufficient, it may lead to structural loosening, water leakage, and other issues.
- Compatibility: The chemical compatibility between the sealant and the contact materials (such as glass, aluminum, etc.). If the silicone sealant reacts negatively with these materials (such as expansion or corrosion), it can compromise the safety and performance of the entire structure.
- Contamination: If silicone sealant becomes contaminated during use (for example, by migrating oils or pollutants), it can affect its performance, and may even lead to surface staining or a decline in effectiveness.
The Impact of Sealant Application on Quality
Silicone structural sealant has very strict technical requirements during the application process. It is essential to thoroughly clean and prepare the building’s exterior walls. In our actual cases, we have encountered customer feedback about adhesive failure, which was eventually traced back to the lack of professionalism of the hired workers. During sealant application, it is crucial to ensure that the bonding areas are clean and dry. When applying the sealant, it must be spread evenly and in the right amount to avoid interference from release agents on the curtain wall that could affect the waterproof performance of the sealant. Unfortunately, some construction teams fail to follow standards, or even cut corners, resulting in uneven application of the sealant. This not only severely affects the waterproof quality of the sealant, but also leads to issues like cracking and detachment of the sealant during the use of the glass curtain wall, posing significant safety risks.
