The mechanical behaviour of SentryGlas® ionomer and TSSA silicon bulk materials at different temperatures and strain rates under uniaxial tensile stress state

An innovative type of connections for glass components, called laminated connections, has been developed in the last years. Two materials have been used for laminated connections: the transparent ionomer SentryGlas® (SG) from Kuraray (former Dupont) and the Transparent Structural Silicon Adhesive (TSSA) from Dow Corning. In this paper, the mechanical behaviour of SG and TSSA bulk materials is studied under uniaxial tensile stress condition. The effects of strain rate and temperature variations are investigated. Particular attention is paid (i) to the study of these polymers in cured condition and (ii) to the computation of true stress and strain field during the tests. Firstly, it is observed that the mechanical behaviour of both SG and TSSA are temperature and strain rate dependent. These effects are quantitatively determined in the paper. Secondly, two additional phenomena are observed. For TSSA, it is observed that the material goes from fully transparent to white colour, exhibiting the so-called whitening phenomenon. For SG, instead, it is observed that the strain field distribution is dependent on the temperature. More specifically, the material exhibits a non-uniform strain field distribution due to the occurring of the necking phenomenon. Measurements along the specimens, using Digital Image Correlation techniques, showed that the localized strain propagates over the full specimen length, resulting in a cold-drawing phenomenon. Finally, it is also shown that engineering and true stress–strain definition exhibits large deviation indicating that the finite deformation theory should be used for the computation of the stress–strain curves to be implemented in numerical modelling.