A novel sealant-testing device was used to con-tinuously monitor the mechanical properties of a one part silicone sealant for movement cycles initiated from 10 h to 168 h after sample creation. These cure times fall between the proposed RILEM TC-139 technical recommendation of 5 min and the ASTM C719 durability standard of 21 d. Apparently, enough cross-linking occurred prior to testing such that neither the overall movement history of the sam-ple nor the deformation step shapes affected subsequent curing or mechanical properties of the sealant. A critical parameter for sealant performance appears to be the extent of cure at the onset of movement and not the extent of movement or step shape contrary to several literature references.
Citation: Adhesion Society
Pub Type: Journals
adhesion, filled elastomer, mechanical properties, modulus, movement during cure, networks, rubber, sealant, silicone