The main function of silicone weather-resistant sealant is to ensure the air tightness and water tightness of the curtain wall; It is divided into single component, two component, acid curing adhesive, neutral curing adhesive. Now entering the winter, the climate change is large, the humidity is reduced, it may reduce the effect of weather resistant glue, resulting in curtain wall air leakage and water leakage affect the normal use, construction, most choose single component silicone glue. Surface dry test and anti-viscosity test
The problems that may exist in the construction of Silicone Sealant in winter are analyzed. One: Slow curing Silicone glue in the process of curing with water molecules is gradually from the surface to the inside, but into the autumn and winter, the temperature and humidity of the environment have a significant impact on the curing speed, and the antistick, surface dry and deep curing of the sealant will be slowed down. Moreover, sealant products on the market are divided into summer formula and winter formula, different formulas, curing time has a significant difference, in the purchase process according to their own construction environment requirements to distinguish. Under standard conditions (temperature (23±2)℃, relative humidity (50±5)%), the surface drying time of single component silicone sealant is within 3 hours, and the viscosity removal time is within 24 hours. Under low temperature conditions in winter, the surface drying time and desticking time will be extended significantly. The silicone sealant cracked due to stampede at the initial stage of curing
Two: Cracking In the case of low humidity and temperature, the curing speed of silicone rubber is slowed down, and when it is not fully cured, the plate contraction or deformation will produce a large stretch of the sealant, which is easy to cause the surface cracking of the sealant, when the plate is a deformation, it may be that the displacement capacity of the main sealant can not meet the deformation requirements of the plate sealant. The displacement capacity of sealant can not meet the deformation requirements of plate joint resulting in cracking phenomenon
There is also a case that the size error or installation error of the aluminum plate of the glue seam itself is too large, resulting in a large size deviation, the actual size of the glue seam is much smaller than the design size, the actual displacement capacity of the sealant is higher, and even leads to high displacement level sealant can not meet the requirements of the glue seam deformation. The construction deviation of joint size is large
If the weather resistant sealant is still used during construction to meet the displacement capacity of the original design joint, it will not be able to meet the deformation requirements of the plate. This is similar to the first case above, sooner or later the seams will crack. During the construction in winter, the plate deformation is large, and the cracking may occur in the initial curing of the sealant. Silicone sealant used as a joint according to the standard 20HM, 20LM, 25HM, 25LM and other models, different models of silicone sealant have different displacement in practice. Three: the substrate cleanliness is not enough Silicone sealant after vulcanization due to the surface cleanliness is not low bonding strength, displacement deformation due to poor bonding strength and fall off from the surface cracking. Therefore, the weather resistant sealant must be selected to meet the joint deformation requirements of the sealant, the actual installation of the glue seam size must also meet the design requirements, to ensure that the initial curing of the sealant plate can not produce excessive deformation, to avoid the risk of cracking.
We are from China rubber industry Tongchuang.
We specialize in the production of Neutral Silicone Sealant, Acid Silicone Sealant, Structural Sealant, silicone sealant, silicone sealant. We can produce sealants with warranties ranging from 1 to 25 years and pack them according to your requirements.
I hope we can cooperate happily in the near future. If you have any questions, please don't hesitate to contact me.
Shandong Tongchuang Rubber Industry Co.,Ltd.
