Insulating glass is a kind of energy saving glass which has been widely used in commercial office buildings, large shopping malls, high-rise residential buildings and other buildings. It has excellent heat insulation and sound insulation performance and is beautiful and practical. Insulating glass is made of two pieces (or more) of glass and the interval bar bonded, sealing type mainly adopts the adhesive strip method and the bonding method, and the current use of two. Most of them are the double-channel sealing structure in the adhesive sealing structure. Its structural form is shown in Figure 1: two pieces of glass are separated by spacer bars, and butyl adhesive is used between the spacer bars and the glass.. Channel sealing, the spacer strip is filled with molecular sieve, and the gap formed by the edge of the glass and the outer side of the spacer strip is sealed with two channels of sealant. Insulating glass glue manufacturer for you to introduce!

The role of a sealant is to prevent water gas or inert gas from entering and leaving the cavity. Generally, butyl rubber is used, because the water gas transmittance and inert gas transmittance of butyl rubber are very low. But butyl glue itself has low bond strength and small elasticity. It must be fixed by two sealant on the overall structure, and the glass plate and the spacer are bonded together, so that the insulating glass can maintain a good sealing effect when it bears the load, and the overall structure is not affected.

Type of insulating glass secondary sealant

Two insulating glass sealant mainly includes polysulfide, polyurethane and silicone. At present, polysulfide and silicone are the main types in the domestic market, while polyurethane appears late in China and is less used. Table 1 lists some of the properties of the three gels after full curing.

The advantage of polysulfide sealant is that the permeability of water gas and argon gas is low at room temperature; The disadvantage is that the water absorption rate is higher, the modulus and elastic recovery rate decrease greatly with the increase of temperature, and the water gas permeability is larger when the temperature is higher. In addition, due to its poor ultraviolet aging resistance, long-term ultraviolet irradiation will have non-stick degumming phenomenon. The advantages of polyurethane sealant are that the permeability of water and argon is low, and the permeability of water is relatively low when the temperature is high; The disadvantage is that the resistance to UV aging is poor.

Silicone sealant refers to a kind of sealant with polysiloxane as the main raw material, also called silicone sealant. The polymer chain of silicone sealant is mainly composed of Si -- O -- Si, which is crosslinked into a network Si -- O -- Si skeleton structure during the curing process. The Si -- O bond energy (444KJ/mol) is very high, which is not only much higher than other polymer bond energy, but also higher than UV energy (399KJ/mol). The molecular structure of silicone sealant makes silicone sealant has excellent high and low temperature resistance, weather resistance and UV aging resistance, and low water absorption; The disadvantage of insulating glass is high gas permeability.

The correct selection of two insulating glass sealant

If the adhesive surface of polysulfide glue, polyurethane glue and glass is exposed to sunlight for a long time, there will be degumming phenomenon, which will lead to the outer piece of hollow glass curtain wall of hidden frame glass or the hollow glass seal failure of point support glass curtain wall. Therefore, silicone structural sealant must be used for the hollow glass of hidden frame curtain wall and semi-hidden frame curtain wall. And the interface size should be calculated according to JGJ102 "Technical Specifications for Glass Curtain Wall Engineering"; Silicone structural sealant must be selected as the second insulating glass sealant of point-supported glass curtain wall; Insulating glass silicone structural adhesive is recommended for the second insulating glass sealant of the curtain wall of large frame. Two insulating glass sealant for doors, Windows and ordinary light frame curtain wall can be hollow glass silicone sealant, polysulfide sealant or polyurethane sealant.

Based on the above, the user should choose the appropriate insulating glass two-channel sealant products according to the specific application of insulating glass. Under the premise of qualified sealant quality, as long as the selection and use of proper, can be made to meet the life of the use of insulating glass requirements. But if the choice and use is improper, even if the best sealant may produce unqualified hollow glass. In the selection of two sealant, especially silicone structural sealant, but also comprehensive consideration of silicone sealant to meet the functional requirements of insulating glass, and a sealing butyl rubber compatibility problem, silicone sealant performance should meet the relevant standards. At the same time, the quality stability of silicone sealant products, the quality of silicone sealant manufacturers and manufacturers in the pre-sale, sale and after-sales process of the technical service ability and level are also important factors for users to consider.

The proportion of insulating glass sealant in the manufacturing cost of the whole insulating glass is low, but it has a great impact on the quality and service life of insulating glass. Insulating glass structural sealant is even directly related to the security of curtain wall. At present, with the increasingly fierce competition in the domestic sealant market, some sealant manufacturers in order to win customers at a low price, at the cost of reducing the sacrifice of product performance and quality, there are a considerable number of low quality and low price insulating glass sealant products on the market. If the user chooses carelessly, in order to save a little sealant cost, and bring safety risks and even lead to quality accidents, may cause heavy losses.

Small series of insulating glass glue in this call must choose the right products, to choose good products; At the same time, the use of low quality insulating glass sealant and improper use of various hazards will be presented to you in the future.