Why Does Sealant Change Color?

The Yellowing of Sealant

The main ingredient in mainstream epoxy sealants is epoxy resin. In the sealant formula, the combined A and B component epoxy resin content exceeds 50%. Given that epoxy resin is the primary component, discoloration is inevitable, merely a matter of time. The materials contain chromophoric groups, such as the aromatic ether and benzene ring structures in epoxy resins, and the conjugated double bond structure in unsaturated resins. These structures produce colored substances under UV radiation or oxygen oxidation, manifesting as material yellowing and powdering.

Additional Causes of Sealant Discoloration

1. Uneven material mixing during application, leading to softening and subsequent discoloration.
2. Contamination of tile joints with chemicals or moisture.
3. Low temperatures, high humidity, open windows during application, contact with water before drying, or exposure to strong acids or alkalis.

Are There Non-Yellowing Sealants?

Indeed, some manufacturers have introduced polyaspartic polyurea sealants, a new material different from epoxy systems. Its anti-yellowing performance far exceeds that of epoxy-based sealants. Polyaspartic polyurea has a pure aliphatic structure, free from double bonds and benzene rings prone to yellowing. It fundamentally resolves the issue of sealant yellowing. Moreover, it maintains strong resilience even under humid conditions, unaffected by environments like return-to-south weather or rainy days, as long as the base surface is not overtly wet. Additionally, polyaspartic polyurea itself is a waterproof and anti-corrosion material, retaining these properties when formulated into a sealant, thus offering excellent resistance against everyday chemical corrosion.

Feiyang has been specializing in the production of raw materials for polyaspartic coatings for 30 years and can provide polyaspartic resins, hardeners and coating formulations. Some of our polyaspartic coating formulations: Polyaspartic Coating

Feel free to contact us: marketing@feiyang.com.cn

Our products list:

• Polyaspartic Resin
• Isocyanate Hardener
• Special Chemical

Learn more polyaspartic knowledge: Polyaspartic FAQ

Shenzhen Feiyang Protech Corp., Ltd. specializes in researching and producing polyaspartic polyurea resin and other new chemical products. We are recognized as a "National Special New Key Little Giant" and a "State-level High-tech Enterprise", with more than 50 polyaspartic polyurea invention patents. We also participated in the preparation of 13 industry standards for polyaspartic polyurea materials as a leading company in this field, ranking No.1 in the Chinese market.

In the coating industry, polyaspartic polyurea is used in construction machinery, automobile, containers, fan blades, marine heavy corrosion protection, and high-end industrial and commercial floor coatings. In the adhesive field, it is mainly used in sealants, stone adhesives, electronic adhesives, film circuit packaging adhesives, and other high-end applications. In the waterproofing materials sector, it is primarily used in hydroelectric dams, water parks, building waterproofing repair materials, and other areas. In the structural materials field, it is applied to curling tracks, artificial ice skating rinks, and other structural materials.

Polyaspartic polyurea is considered a high-end new material in the strategy of manufacturing power. We have broken the foreign technology monopoly and filled the domestic market gap. Due to its comprehensive characteristics of "Environmental protection, Energy saving, and Long durability", polyaspartic polyurea can contribute to the realization of genuine carbon neutrality in the coatings, adhesives, and materials industries.

Since 2012, Feiyang polyaspartic ester resin has been supplied overseas. It has been widely used to replace Bayer's current polyaspartic system in many coating companies and has been applied in anti-corrosion and waterproofing by international coating companies.