ISSN: 1945-7553
CODEN: JTEVAB
Published Online: 1 August 2012
Page Count: 6

Investigation of Interaction between the Silicone Rubber Sealant and Concrete Substrate

Liu, Jiesheng
School of Civil Engineering and Architecture, Wuhan Polytechnic Univ., Wuhan,

Wu, Shaopeng
Key Laboratory of Silicate Materials Science and Engineering of Ministry of Education, Wuhan Univ. of Technology, Wuhan,

Lu, Haijun
School of Civil Engineering and Architecture, Wuhan Polytechnic Univ., Wuhan,

(Received 8 March 2012; accepted 15 May 2012)

Abstract

This investigation aimed to study the interaction between concrete substrate and silicone rubber sealant. Several surface treatments were applied in order to obtain different levels of surface roughness in concrete substrates. The bond tensile test showed that abrasion and solvent cleaning methods improved the bond strength relative to that of untreated substrates. The effects of silane coupling agents on the bond strength was studied via two methods of application of the coupling agent, namely, (a) pre-treatment of concrete substrate in an aqueous solution of silane, and (b) adding silane to the silicone rubber sealant as an integral blend additive. No significant differences in bonding values were noted between the two methods. An increase in the amount of silane coupling agent increased the bond strength of the silicone rubber sealant, but beyond a certain point, further increases in the amount of silane lowered the bond strength. As the amount of silanes increased, the failure mode of the samples changed from adhesive failure to cohesive failure. Scanning electron microscopy and contact angle methods were employed to investigate the interface. The results strongly suggest that interface adhesion and treatments are crucial factors in creating a durable bond interface between substrate and sealant.

Keywords:
silicone rubber sealant, interface, substrate

Paper ID: JTE20120048
DOI: 10.1520/JTE20120048
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