硅酮密封胶在建筑幕墙应用中的粘接性能对比试验

Comparative test on the adhesive performance of silicone sealant in the application of building curtain walls

建筑幕墙密封胶在使用一定时间后,会出现干裂,粘接性能降低等问题。以α,ω-二羟基聚二甲基硅氧烷为主要原料,研究采用107胶、甲基硅油等多种材料制备胶体混合液,分别添加3种不同的纳米活性轻质碳酸钙,并在3种混合液中继续加入催化剂与交联剂,制成JT1、JT2与JT3这3种硅酮密封胶试件,测试不同密封胶试件性能。结果表明,JT1硅酮密封的拉伸模量、挤出性以及断裂伸长率均高于其他两种试件。当添加不同含量的交联剂时,JT1硅酮密封始终保持最快的固化时间与表干时间;当试件养护时间不断增加,JT1硅酮密封胶依然可以保持最高的粘接能力与硬度,且JT1硅酮密封胶受紫外光老化与热水老化的影响较小;当热温达到90℃时,JT1硅酮密封胶的粘接强度为0.674 MPa。

After a certain period of use,the building curtain wall sealant will have problems such as dry cracking and reduced bonding performance.Usingα,ω-dihydroxy polydimethylsiloxane as the main raw material,a colloidal mixture was prepared with 107 glue,methyl silicone oil and other materials,and three different nano-active light calcium carbonates were added respectively.The catalyst and cross-linking agent were added to the three mixed solutions to make three kinds of silicone sealant specimens JT1,JT2 and JT3,and the properties of different sealant specimens were tested.It has been verified by experiments that the tensile modulus,extrudability and elongation at break of the JT1 silicone sealant are higher than those of the other two specimens.When the crosslinking agent is used,the JT1 silicone sealant always maintains the fastest curing time and surface drying time;when the curing time of the specimen continues to increase,the JT1 silicone sealant can still maintain the highest bonding ability and hardness,and the JT1 silicone sealant is less affected by ultraviolet light aging and hot water aging.When the heat temperature reaches 90℃,the bonding strength of JT1 silicone sealant is 0.674 MPa.