脱酸型有机硅密封胶浸水粘接性的研究

Study on the Adhesive Properties of Acid-cured Silicone Sealant

以α,ω-二羟基聚二甲基硅氧烷为基础聚合物、气相白炭黑为补强填料、配合醋酸型交联剂、催化剂制备出单组分脱酸型有机硅密封胶。重点考察了基础聚合物的挥发份、增塑剂用量及添加工艺、氯离子浓度对密封胶性能的影响,尤其是对密封胶与基材浸水粘接性的影响。结果表明,随聚合物中的挥发份和增塑剂比例的增加,密封胶与基材的浸水粘接性变差;当体系中的氯离子浓度超过100 ppm(1×10-4)时,密封胶与基材浸水后完全脱粘。

Acid cured RTV-I silicone sealant was prepared by using α,ω- hydroxyl terminated polysiloxane, fumed silica, acetoxy crosslinker, catalyst and other additives. Influences of different factors on properties of silicone sealant, especially adhesive properties and adhesive properties after immersion in water with substrate, were investigated. The results indicated that with the increase of polymer distillates and plasticizer, the adhesive properties of silicone sealant decreased. Silicone sealant debonded from substrate after immersion in water when the concentration of chlorine ion in the system was beyond 100 ppm（1 ×10^-4）.