Doors and windows generally use EPDM rubber sealant strip, thermoplastic EPDM/PP rubber strip, plastic polyvinyl fluoride sealant strip. The details are as follows:
1. EPDM rubber sealant strip
Excellent comprehensive performance, ozone proof, weather resistance, high temperature resistance, low temperature resistance, chemical resistance, resistance to a variety of polar solutes, the density is relatively small. The disadvantage is that it is generally mineral oil and has a large amount of lubricating oil expansion. It is generally used for dark products, and the operating temperature range is-60 ~ 150℃. It is suitable for high temperature, cold, coastal areas, ultraviolet radiation and high-rise buildings. Its wide application range and excellent comprehensive performance have been recognized by the door and window industry at home and abroad.
2. Thermoplastic EPDM/PP rubber strip
Due to the flexibility and elasticity of rubber, it can be produced by plastic processing without curing, and the waste can be recycled. It is a material with a wide range of properties, good heat resistance, cold resistance, relatively small density, oil resistance, solvent resistance, similar to fluorobutyl rubber, pressure resistance, long-term deformation. Can meet the requirements of various colors, working temperature range-40 ~ 150℃, suitable for cold high-rise buildings.
3. Plastic polyvinyl fluoride sealant strip
The material is cheap and easy to get, corrosion resistant, wear resistant, acid and alkali resistant, various chemical Media, fire resistance and high mechanical strength. The disadvantage is that the plasticizer in the system is easy to migrate, becomes hard and brittle with the extension of time, loses elasticity, does not resist aging, has poor weather resistance and low temperature performance. Generally, dark color products are suitable for occasions where light is not strong, temperature changes are not big, and weather conditions are not bad.
There are three types of commonly used door and window sealing strip
1. Modified PVC strip
Modified PVC strip: the price is relatively low. Due to different quality, low-end products use waste, substitute plasticizer and high filling amount, resulting in poor elasticity of rubber strips, easy to harden, and pungent smell, easy migration makes the frame yellow and has a short service life. PVC products contain halogen and heavy metals in stabilizer, which is not conducive to environmental protection. Therefore, developed countries abroad, Beijing and coastal cities in China have eliminated or restricted the use of PVC strip.
2. Vulcanized EPDM sealing strip
Vulcanized EPDM rubber sealing strip: it is stronger than PVC strip in terms of sealing elasticity durability. However, due to the need for microwave curing line setting, the processing energy consumption is high, which is usually more than 20 times that of PVC processing, the product cannot be reused, is not environmentally friendly, and is not a product advocated by the state. Therefore, basic enterprises do not use it.
3. Thermoplastic EPDM sealing strip
Thermoplastic epdm rubber sealing strip this sealing strip is a new material developed on the basis of imported technology from abroad and domestic independent research and development in recent years. It is mainly used in sealing strip for automobile window and door and has been used in building door and window sealing strips in recent years.
The outstanding advantages of thermoplastic EPDM sealing strip are:
① performance and service life are equivalent to vulcanized EPDM rubber sealing strip.
② the processing energy consumption is lower than that of vulcanized EPDM strip (equivalent to PVC).
③ It does not contain heavy metals such as halogen and lead, and can be recycled after several years, which meets the requirements of green building materials.
④ the proportion is small (only 0.9-0.95) and the window output rate is high. It seems that the purchase price is high and the actual use cost is low. This kind of product has developed rapidly in the use of building doors and windows in recent years.
Features of high quality door and window sealing strip
1. Light bulk density, high expansion strength and no water absorption (replacing traditional three oil four felt, asphalt wood fir board and other materials). The product is environmentally friendly, easy to construct, and has good anti-seepage, leak-proof and water-proof effects.
2. Corrosion resistance, aging resistance, high and low temperature resistance 80 ℃ ~-45 ℃ no flowing, no deformation, no brittle crack, long service life.
3. It has an independent open-hole bubble structure. The appearance of the special type joint board is that the honeycomb holes are evenly distributed. It can be tightly bonded with cement/sealant without wool to adapt to the changes of natural expansion and contraction, enhance the sealing expansion and sealing effect of joints.
How to distinguish the quality of sealant strip?
1. Combustion method (can distinguish thermoplastic body and rubber strip)
A. Rubber rubber strips become ash after burning and cannot be brushed. Among them, the ash part is white, and the one which is still white after rubbing on white paper will be extinguished is silicone rubber; The ash part is black, and the one which is black after rubbing on white paper is extinguished is EPDM or neoprene rubber; the ash is black, and it is natural rubber if you touch it with a sticky feel when it goes out.
B. After burning, the thermoplastic elastic rubber strip can be pulled into filiform at the place where it goes out, in which EVA (ethylene-vinyl acetate copolymer) has obvious acetic acid smell. PE (polyethylene) and PP (polypropylene) have obvious smell of candle burning, which can be burned continuously and accompanied by low melting. PVC (polyvinyl chloride) adhesive strip has the characteristics of extinguishing when it is off fire, and it is accompanied by black smoke and pungent odor.
C.TPV thermoplastic vulcanized rubber: The surface is Matt, there is a phenomenon of melting and drawing, floating on the water surface or suspended state in the water.
D.SEBS thermoplastic elastomer sealing strip: the surface is Matt, there is the phenomenon of melting and drawing, and it sinks slowly in the water.
2. Tension measurement
Relatively speaking, as a sealant strip material, it should have a certain tensile strength, and the standard requirement is that the strength is greater than or equal to 5Mpa. The higher the latex content of the same material, the better the tensile force. Generally speaking, the service life will be relatively long and the sealing effect will be better.
3. Smell
Use your nose to smell whether there is peculiar smell. The normal PVC material has a little mellow smell and hardly smells bad smell.
4. Wrap the sealing strip around the profile as tightly as possible and place it under high temperature for a period of time (on the roof or in a sunny place).
Check whether the contact surface between the profile surface and the sealing strip is stained and discolored, whether the dust on the surface of the sealing strip is yellow (it is easy to absorb soil with oil), and whether it is dirty with hands.
5. There will be a lot of filler for some cheaper sealing strips, so the surface will not be very bright, and those who are cheap and have no bright appearance are not desirable.
The sealing performance of doors and windows mainly depends on the sealing strip. The performance and service life of sealing strip products mainly lie in the selection of materials. Therefore, we recommend that you purchase high quality door and window sealing strip!
