Since silicone sealant has excellent high and low temperature resistance and weather resistance, it has been widely used in construction. However, we often encounter discoloration when using silicone sealant. This article will specifically analyze the causes and solutions of silicone sealant discoloration.
1. Contact with rubber and other materials
Silicone sealant discolor when it comes into direct contact with most rubbers (natural rubber, chloroprene rubber, EPDM rubber), which are widely used in curtain wall and door and window sealing (such as rubber strips, rubber pads, etc.).
2. Incompatibility between different sealants
Different types of sealants cannot be mixed to use , which will affect each other and cause discoloration. For example, acid sealants will turn oxime sealants yellow, and the use of neutral oxime and neutral alcohol sealants at the same time will also cause yellowing.
3. The substrate is not clean
4. Environmental factors
This type of discoloration often occurs in neutral oxime sealants. The main reason for the discoloration is that the air contains acidic substances.
5. The quality of silicone sealants is poor
Some manufacturers fill a large amount of white oil in silicone sealants. After the white oil evaporates, the sealant shrinks greatly, which often causes silicone sealant discolor and cracking of the glue seams.
How to avoid silicone sealants discolor?
1. Before construction, compatibility tests are necessary to ensure the compatibility of sealants with other materials. More compatible accessory materials can be selected, such as using silicone rubber products instead of rubber products to reduce the risk of yellowing.
2. During construction, neutral sealants and acidic sealants must be used in isolation. Once neutral sealants encounter acidic substances, they will decompose to produce amine substances, which are easily affected by air oxidation and discoloration; during use, neutral sealants should be avoided from contact with corrosive environments such as acids and alkalis to ensure construction quality and effect.
3. Choose sealants with guaranteed quality
Tengyu chemical (longkou) Co. ,Itd is a professional supplier of sealants and adhesives in China with 12+ years of export experience, Integrate the Research & Development, Quality Control, and Sales of Acrylic sealant, Silicone Sealant, Polyurethane Sealant, MS Sealant, Waterproofing Coating, Chemical Anchor Adheisve, Wood Glue, PU Foam, Anaerobic Adhesive, etc.
Tengyu products engineers can provide sealant solutions for the project, including door and windows, curtain walls, IG glass, indoor decoration, bath and kitchen, etc.
Here, we recommend the following sealants for you:
TNS721 One Component Silicone Sealant for Curtain Wall Glass
TNS721 Siliocne sealant is a kind of Silicone Weatherproof Sealant with one component and neutral cured at room temperature, which has a excellent performance like strong adhesion, high strength, high elasticity, high modulus, strong ability to resist movement.
TNS731 Neutral Weatherproof Silicone Sealant
TNS731 Neutral Weatherproof Silicone Sealant is a one-part, durable, neutral- cure, architectural grade sealant. with excellent adhesion for use on a wide variety of materials in new or renovated weatherproofing applications. It cures into an elastic rubber body by reacting with moisture in the air to form an effective seal. Excellent weather resistance and load-bearing interface ±35% telescopic displacement.
TNS771 Neutral Silicone Sealant For Windows and Doors Installation
TNS731 Neutral silicone sealant with high and low temperature resistant performance, remain performance constant within -40 ºC to 150 ºC. Suitable for all kinds of doors and windows glass installation, sealing and many other building and industrial applications.