Silicone sealing strip is one of the important components of building doors and windows. It closes between the profile and the glass, between the frame and the leaf through the elasticity of the lip cavity flange in the body structure and the contact pressure generated by the contact surface, effectively Prevent the leakage or intrusion of internal and external media (rainwater, air, sand and dust, etc.), prevent mechanical vibration, impact and damage, so as to play the role of sealing, sound insulation, heat insulation and insulation, and obtain excellent waterproof and thermal insulation for energy-saving building doors and windows , sound insulation, sealing and other performance play an important guarantee, so the sealant is the key to energy-saving doors and windows.
As a key material for energy-saving doors and windows, silicone sealing strips play an important role in watertight, airtight and energy-saving in doors and windows. As a revolutionary sealing product, providing perfect sealing for energy-saving doors and windows, it has the following unparalleled performance advantages.
1. Excellent cold resistance and heat resistance
Silicone rubber can be used for a long time in the environment of -70OC ~ 200OC. The good high and low temperature performance of silicone rubber is especially important in China with a large latitude range. In southern China, the temperature of doors, windows and walls facing the sun in summer is normal at 70OC. , and it is not surprising that the climate in the northern region is -40OC in winter. The huge temperature difference severely restricts the use of PVC, thermoplastic elastomers, and EPDM rubber. General plastics, rubber or elastomers are already brittle at -20OC, and cannot be constructed even at 0OC. However, when the silicone rubber is at -70OC~200OC, the physical properties do not change much at all.
2. Excellent weathering resistance
Whether it is plastic or EPDM organic rubber, its materials are basically composed of carbon-oxygen chains and carbon-carbon chains. The C-O and C-C bond energies of these materials (336KJ/mol and 356KJ/mol, respectively) are lower than the UV radiation energy (370 KJ/mol). Chain scission is also prone to occur in thermal aging environments, leading to degradation of the material. It shows that the sealant strip is not resistant to ultraviolet aging and heat aging. The main chain of silicone rubber is basically a silicon-oxygen bond structure, and the Si-O-Si bond energy (452KJ/mol) is higher than the ultraviolet radiation energy, so silicone rubber has excellent weathering resistance. Under the influence of sun, rain, water and ozone, after 30 years of aging outdoors, the performance does not decline significantly, and it can be synchronized with the service life of doors and windows, which cannot be achieved by other materials.
3. Good elasticity and resilience
Building doors and windows are always subject to mechanical changes from the outside world and themselves, such as thermal expansion and contraction, instantaneous loads, wind loads, earthquake effects, long-term loads: self-weight, temperature difference deformation, snow loads, etc. Silicone rubber has excellent elasticity and good compression deformation, which is unmatched by other rubbers and plastics. Silicone rubber can be adjusted arbitrarily between Shore 30A-85A to achieve the best sealing performance.
4. Safety and environmental protection
In 1954, silicone rubber was confirmed in human experiments: "non-toxic, odorless, non-adhesive to human tissue and blood, good biological adaptability, and when the warm-blooded animal tissue that is extremely sensitive to the outside world comes into contact with silicone rubber products, its cell tissue is not found. Abnormal.” The announcement of the results also shows that only silicone rubber is the safest elastomer material in the environmental protection and medical circles. In the US FDA (US Food and Drug Administration) certification, so far as a new environmental protection material, there is no one that is more harmless to the human body than silicone rubber. It is undoubtedly of special significance to highlight its excellent environmental protection performance in buildings.
5. Good air permeability and selective air permeability
The latest research shows that the oxygen transmission rate of silicone rubber is 25 times that of natural rubber and 428.6 times that of butyl rubber (IIR). This performance can keep the room fresh air and is most suitable for people's life.
6. The surface is smooth and clean, with various colors
It has good surface performance, and the color can be made into colorful ones, which can be matched with door and window profiles of any color, and has a very good decorative effect. Excellent surface properties, anti-sticking, hydrophobic.
With the change of human living environment, modern building doors and windows have experienced from steel doors and windows to plastic steel doors and windows, ordinary aluminum alloy doors and windows to broken bridge insulation doors and windows, and system doors and windows. The era of natural rubber seals has developed into modern silicone rubber seals, so the role of silicone seals in door and window accessories has become more and more apparent.

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