Studies on the effect of movement during the cure on the mechanical properties of a silicone building joint sealant

• Published in: Polymer engineering and science Vol. 50; no. 1; pp. 113 - 119
• Main Authors: White, C.C, Hunston, D.L, Williams, R.S
• Format: Journal Article
• Language: English
• Published: Society of Plastics Engineers, Inc 01-01-2010
• Subjects: Analysis; Crosslinked polymers; Mechanical properties; Silicones
• ISSN: 0032-3888; 1548-2634
• DOI: 10.1002/pen.2l518

A novel sealant testing device was used to continuously monitor the mechanical properties of a one-part silicone sealant for movement cycles initiated from 10 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 standard of 21 days. At 10 h of cure, enough crosslinking occurred before testing such that neither the overall movement history of the sample nor the deformation step shapes affected subsequent curing of the sealant. A critical parameter for sealant performance appears to be the extent of cure at the onset of movement. POLYM. ENG. SCI., 50:113-119, 2010. [C]2009 Society of Plastics Engineers*