Kinetic behavior of the reaction between silica and epoxidized liquid rubber

Abstract

SbstractThe use of epoxidized rubber as compatibilizer in silica-filled rubber compounds has been proposed in literature. However, the investigation of the reaction kinetics between the epoxy groups and the hydroxyl groups at the silica surface is not yet described. It is a difficult task, mainly because of the high dilution of the system due the difficulty of incorporating high levels of silica in a matrix containing epoxidized rubbers of high molecular weight. In this work, a mixture of precipitated silica and an epoxidized liquid rubber (EpLHPB) was prepared and the reaction between silanols and epoxy groups was followed by DSC under isothermal conditions, at 150, 160 and 170 °C. An autocatalytic data treatment was applied to determine the kinetic parameters of the reaction. Furthermore, it was possible to estimate the amount of epoxy groups required for the saturation of the external surface of the silica, resulting in 5.4 epoxy groups/nm 2 .

Biologically sustainable rubber resin and rubber‐filler promoter: a precursor study

“…On the other hand, ENR is the most favored rubber for the construction of green tire tread due to the low rolling resistance combined with high traction properties . Epoxidized natural rubber alone cannot deliver the properties to competition with those of silica‐bis(triethoxysilyl propyl) tetrasulfide (TESPT) filled NR . Bio‐resin, which is natural, economical and eco‐friendly, has been tentatively used as a processing aid and to enhance tack adhesion .…”

“…In order to enhance the silica dispersion, many efforts have been carried out with silica surface modification in recent years . The other end silane grafted NR and maleic anhydride grafted NR were used as compatibilizers in silica filled green composites . Small angle X‐ray scattering (SAXS) techniques are very suitable for the study of filler morphologies in silica‐filled rubber compounds .…”