Improvement of mechanical, thermal and morphostructural properties of SBS thermoplastic elastomer using kaolin and dolomite microparticles with modified surface

Abstract

The aim of this paper was to assess the influence of the modification of the surface of dolomite and kaolin with SiO2 and TiO2 precursors, on the block copolymer styrene-butadiene-styrene (SBS) type thermoplastic rubber properties. These composite materials were obtained by compounding SBS with various ratio of powders. Based on the SEM images it can conclude that the powders were homogenously dispersed in to the SBS matrix. The dolomite particles can be clearly identified in the SEM images as particles of 10 micrometers. The samples obtained with modified dolomite have similar morphology. The EDS elemental distribution confirming a good corroboration between the elements of the dolomite, kaolin and titanium or silicon elements. Based on the thermal analysis according to the residual mass, the presence of 20% mineral phase can be confirmed. According to the DSC curves a strong stabilization of the composite appears, because of the presence of the mineral component. According to the physical-mechanical data all the composite materials exhibit improved mechanical properties. Additionally, the modification of the kaolin and/or dolomite bring important improvements in mechanical properties. The samples 13 and 14 exhibit high tensile and tear strength. These composites can be used for various applications, such as, for instance, soles for firefighters' footwear.