Research on Adhesive Selection of Hollow Glass Edges

The construction of insulating glass is a unit member of a sealed and adhesive device at the distance from the glass. It is composed of two sealant layers for sealing moisture from the sealant. The moisture entering is absorbed by the desiccant in the frame, and the gas in the cavity is absorbed. Continued boring is the basis of insulation. Bonding structure and soaking way (Figure 1), dry noise agent absorbs water vapor through the seal layer, the quality continues to add until the moisture absorption is full, characterized by hollow glass condensation, condensation, that is, the end of product function life. According to the scale of moisture permeable channels, the penetration rate of sealant glue, and the ability of dry-noise agent to absorb moisture, the theoretical calculation of hollow glass boring life should be more than 30 years, but the actual application is far from one another. Condensation, the main factor is product design, material selection and improper or incorrect operation of the device, in the environmental water, water vapor, ultraviolet radiation and chemical media corrosion, air pressure, atmospheric pressure and temperature changes occurred under the pressure difference effect, The marginal sealing adhesive body repeatedly carries and cyclically deforms, accelerates the degradation of the sealing adhesive body, and deteriorates the adhesive sealability to cause dry-up failure.

Experiments indicate that accelerated aging tests under ultraviolet radiation, high-low temperature or high-humidity conditions can be used to evaluate the deterioration trend of the structure and sealant, but useful methods for identifying the longevity should be characterized by changes in the water absorption quality of the molecular sieve under the conditions of use. This experimental method has been chosen for the world's standardized arrangements. Research indicates that temperature-humidity cyclic changes will promote moisture penetration, especially in the continued high-temperature and high-humidity conditions in the cavity gas expansion, hardened high-modulus marginal adhesive super-high stress (such as the temperature of 58 °C hollow glass The helium chamber pressure can reach 13kpa), so that the moisture soaked faster. Combining many years of on-site experience and research results, the European standard EN1279 "Bolith-Insulated Glass for Construction" selects "Method for testing the durability of hollow glass water-gas soaking durability", with the full water absorption rate of desiccant, the initial moisture content, and the final moisture content after the experiment. Calculate the moisture soak index of the insulating glass and characterize the sealing durability of the product. This method has been approved by the European glass bonding device structure certification strategy. Hollow glass cartridges that clearly meet the EN1279 specifications for product quality certification can be used for 25 years.

GB11944-2012 "Hollow Glass" absorbs European experience and research results, characterized by the water soaking index of hollow glass to accelerate its durability, that is, measuring the water absorption increment of the molecular sieve in the hollow glass crucible under high-temperature and high-humidity conditions, accounting for its full water absorption The ratio of the amount, and put forward the moisture saturation index is not more than 0.20 technical indicators. According to this method, verification experiments were conducted on the hollow glass of 40 companies, indicating the usefulness and applicability of the method. Based on the experimental results, this article analyzes the main factors and explores the effect of the type of outer sealant on the service life of the insulating glass.