writer：Liu Jiesheng, Wu Shaopeng
keywords：silicone rubber, substrate, interaction
source：期刊
specific source：Journal of testing and evaluation
Issue time：2012年

This investigation was aimed at studying the interaction between the concrete substrate and silicone rubber (SR) sealant. Several surface treatments were applied to obtain different levels of surface roughness of concrete substrates. The bond tensile test showed that abrasion and solvent cleaning methods improved the bond strength when compared with untreated ones. The effects of silane coupling agents on the bond strength is studied by using two methods of application of the coupling agent, namely by (a) pre-treatment of concrete substrate in an aqueous solution of the silane, (b) by adding the silane to the silicone rubber sealant as an integral blend additive. No significant differences in bonding values were noted between the two methods. The increase in the amount of silane coupling agent increased the bond strength of silicone rubber sealant. Further increase in the amount of silane lowered the bond strength. As the amount of silanes increases, 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 the substrate and sealant.