Ⅰ.What is Rubber?
Rubber’s excellent stretchability stems not only from its softness but also from its unique polymer chain structure and dynamic response. Rubber contains unsaturated carbon chain polymers—isoprene chains in natural rubber and copolymers of butadiene and styrene in styrene-butadiene rubber. These two rubber structures allow them to lengthen when stretched and rebound to their original length when unstretched, maintaining their softness.
However, because rubber contains rigid groups like benzene rings, they can deform over time. Therefore, rubber sealing strips can gradually lose their elasticity after prolonged use, becoming hard and even breaking apart, thus losing their sealing properties.
Different rubbers have different structures. Natural rubber easily oxidizes and hardens over time, while EPDM is more resistant to oxidation. This improves its long-term adaptability, making it an ideal material for door and window sealing strips.
Ⅱ.Why is EPDM widely used?
Below you will learn about the characteristics of EPDM. EPDM: A high-quality raw material designed specifically for sealing applications.
The EPDM molecular structure consists of primarily saturated carbon-carbon chains, unlike the unsaturated backbone found in natural rubber and nitrile rubber. This unsaturated backbone is more susceptible to oxidation by UV rays or ozone, leading to molecular damage and weakened elasticity (this is often the reason why rubber seals break or harden after 3-5 years of use). Furthermore, data indicates that EPDM rubber raw materials are of higher quality and more stable than general-purpose rubbers such as nitrile rubber or styrene-butadiene rubber. This gives EPDM stable elasticity, excellent weather resistance, and longer-lasting safety.
III. Advantages of EPDM Rubber
EPDM’s excellent high and low temperature resistance (maintaining its elasticity and softness in all weather conditions) further enhances its position as an ideal raw material for door and window seals. EPDM’s saturated backbone provides excellent oxidation and ozone resistance, laying the foundation for its long-term durability. It can be used in outdoor environments subject to extreme high and low temperatures. The flexibility of EPDM rubber sealers:
- After deformation, it can recover over 90% of its original shape;
- It maintains constant flexibility even when doors and windows are opened and closed over 20 times a day;
- Remarkably, even after ten years of continuous use, the protective rubber sealing strips can retain over 90% of their initial flexibility, effectively preventing air and water leaks caused by hardening.
The elasticity of EPDM rubber sealing strips: - After stretching, rubber sealing strips recovers to its original shape within one second without any creases;
- It maintains constant elasticity even after being stretched for three or four minutes, making it resistant to breakage.
In short,epdm rubber sealing strips is a high-quality raw material for door and window sealing strips. It can last up to 15 years. If you need sealing strips, consider purchasing EPDM. The higher the EPDM content, the better the quality of the EPDM sealing strip.
