高弹性改性聚醚密封胶的制备与密封性能研究

Study on the Preparation and Sealing Performance of Modified Polyether Sealant with High Elasticity

使用聚醚二元醇等材料实现封端,制备硅烷封端聚醚预聚体,将该预聚体作为基础制备高弹性改性聚醚密封胶。通过试验确定吸附剂用量,分析温度对密封胶弹性影响以及密封胶的固化性能。研究不同湿度下密封胶的吸水率变化,并测试密封胶的粘结性能。试验结果显示,多孔二氧化硅吸附剂能够提升硅烷封端聚醚预聚体性能;密封胶所处环境温度越高,弹性模量呈现下降趋势,弹性恢复率没有出现明显变化;周围环境湿度的增加能够提升密封胶吸水性,使得密封胶不易开裂,养护28 d的密封胶在粘结金属材料和陶瓷材料时密封效果更好,密封性能更高。

The polyether polyols are used to achieve termination to prepare a silane terminated polyether prepolymer,then the prepolymer is used as the basis to prepare a modified polyether sealant with high elasticity.The amount of adsorbent is determined through experiments,and the effect of temperature on the elasticity and the curing performance of sealant is analyzed.The changes in water absorption of sealant in different humidity conditions are studied and the bonding performance of sealant is tested.The experimental results show that porous silica adsorbent can improve the performance of silane terminated polyether prepolymers;The higher the ambient temperature is,the lower the elastic modulus is,and there is no significant change in the elastic recovery rate;The increase in ambient humidity can improve the water absorption of sealant,which makes it be less prone to cracking.The sealants which have been cured for 28 d have better sealing effects and higher sealing performance when bonding metal and ceramic materials.