The aim of the paper is to modify the surface of dolomite with titania (TiO2) and silica (SiO2) precursors, in order to use it as a potential reinforcement material in a polymeric matrix or for environmental applications (photocatalyst for the degradation of organic pollutants based on TiO2). The dolomite surface modification was performed by 2 methods. The first method consisted in modifying the direct dolomite surface with SiO2 and TiO2. The second method consisted in the initial treatment of dolomite with TEOS, in order to form silanol bonds, followed by the addition of SiO2 and TiO2 precursors. The obtained powders were characterized by FTIR, SEM-EDS and DSC-TG. The FTIR spectra prove the formation of the silica network while the samples modified with PDMS exhibit the characteristic peaks of methyl groups from PDMS. In EDS, the presence of the characteristic elements of dolomite (calcium, magnesium, oxygen and carbon) can be observed. When analyzing the modified dolomite powders the presence of titanium and silicon can be observed. The characteristic morphology of the dolomite is preserved in all the samples but, the surface of the larger particles is decorated with smaller particles proving the functionalization of the dolomite, according to the two routes. The thermal analysis is characteristic for dolomite-based materials, the main difference between the samples appearing as a consequence of the burning of the organic part of PDMS, which occur between 400 and 600°C.
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.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.