STP1286: Movement During Cure of Latex Building Joint Sealants

    Lacasse, MA
    Research Officer and Technical Officer, National Research Council Canada, Institute for Research in Construction, Materials Laboratory, Ottawa, Ontario

    Margeson, JC
    Research Officer and Technical Officer, National Research Council Canada, Institute for Research in Construction, Materials Laboratory, Ottawa, Ontario

    Pages: 17    Published: Jan 1996


    Abstract

    The level of performance of high performance building joint sealants clearly diminishes if during cure, the joint in which sealant is placed, undergoes cyclic movement. However, it is less well known the degree to which the movement capability is adversely affected. A preliminary study was undertaken to ascertain the change in performance of a series of water-based sealants and a chemical cured product subjected to movement during cure. Model sealant specimens were subjected to cyclic movement during cure at rates of 12.7mm and 3.2mm / hour such that complete cycles were achieved in 1 and 4 hours respectively. Specimens were evaluated over a single movement cycle having undergone various intervals of cure starting with those cured for 1 day and thereafter cured at 2, 3, 4, 7, 14, 21, 28, 50 and 100 days. Failure was recorded if the sealant bead ruptured or became detached from the substrate. Also, a series of specimens was continuously cycled for 4 days and the change in mechanical response was recorded with time such mat the increase in modulus during cure could readily be determined. Standard tests were also conducted as to the tack free time of these products.

    Keywords:

    in service sealant behavior, joint movement, laboratory test, latex sealants, movement during cure, sealant cure


    Paper ID: STP16299S

    Committee/Subcommittee: C24.32

    DOI: 10.1520/STP16299S


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