Modification of Aircraft Sealant Based on polysulfide with epoxy Resin

Sealants based on polysulfide are one of the most used materials in aerospace industry that have properties such as suitable chemical resistance, ozone and oxygen resistance and self-repairing. On the other hand, this material has some limitation e.g. low cure rate, low shelf life, high compression set and low adhesion to some substrate.so forextending application modifying is necessary. In this work, we use small amount of epoxy resin for increasingadhesion properties and decreasing compression set, without any effect on vulcanization reaction. The incorporationof 2 phr epoxy resin results in reduced compression set of polysulfide sealant from 28.3% to 11.2% after compressed 25% at 23_C for 1 day. At the same time, the ultimate elongation of sealants increases remarkably from 300% to 415%, while the tensile strength decreases from 2.1 to 1.6 MPa

Keywords:

aircraft sealant , mechanical behavior , polysulfide , epoxy resin