低模量装配式建筑单组分硅烷改性聚醚密封胶的制备与性能分析

针对装配式建筑接缝收缩变形、密封胶耐候性差以及密封胶与基材粘接性差等问题,以硅烷改性聚醚树脂为基础聚合物,制备低模量装配式建筑单组分硅烷改性聚醚密封胶,并考察了树脂种类、增塑剂、触变剂及硅烷偶联剂对密封胶表干时间、挤出性和力学性能的影响。结果表明:当m(SAX510)∶m(SAX520)=80∶20,增塑剂DIDP用量控制在85份时,密封胶的弹性模量为0.26MPa,断裂伸长率为600%,弹性恢复率达76%;聚酰胺蜡类触变剂SL用量在3~6份时,挤出效果佳,施工便捷;采用氨基硅烷类偶联剂的粘接效果明显优于环氧硅烷类,同时加速MS密封胶的表干,加入2~5份WD-51,表干时间由原来的90min缩短至45min。

Preparation and performance analysis of one component MS sealant with low modulus for prefabricated construction

Aiming at the problems of shrinkage deformation of the prefabricated construction joints,the poor weather resistance of the sealant and the poor adhesion between the sealant and the matrix,the one component MS sealant with low modulus for prefabricated construction was designed which used silane-modified polyether resin(MS) as matrix polymer. The effects of resin type,plasticizer,thixotropic agent and silane coupling agent on the tack free time,extrudability and mechanical performance of the one component MS sealant were discussed. The elastic modulus, the elongation at break,and the elastic recovery rate was 0.26 MPa,600% and 76%,respectively,when m(SAX510)∶m(SAX520)=80∶20 and the amount of DIDP was 85 pbw. The MS sealant added 3~6 pbw SL exhibited better extrusion and more convenient construction. The bonding effect of aminosilane coupling agent was obviously better than that of epoxy silane. With the addition of 2~5 pbw WD-51,the tack free time was shortened from the original 90 minutes to 45 minutes.