Abstract
The 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/nm2.
Highlights
High-performance rubber materials are usually reinforced between the epoxy groups of an epoxidized natural rubber by colloidal filler such as silica or carbon black, in order to (ENR) and hydroxyls of silicic acid, but without attempting improve their mechanical properties
The low viscosity of this rubber compared with the hydrogen bonds that occur between the allows the intrusion of some chains in the macro- and silanols, resulting in weaker polymer-filler interaction and mesopores of the silica, favoring the impregnation of the greater tendency to agglomerate than carbon black
The reaction kinetics of tetrasulfide (TESPT) are commonly used to enhance mixtures of highly dispersible silica (HD) with a liquid compatibility of nonpolar rubbers with silica and improve hydroxylated polybutadiene epoxidized at 8.8 mol% mechanical properties of silica-filled elastomers, since such (EpLHPB) was studied through isothermal experiments in coupling agents are capable of establishing covalent bonds DSC, from which it is possible to evaluate autocatalytic and between polymer chains and silica surface[1,2]
Summary
High-performance rubber materials are usually reinforced between the epoxy groups of an epoxidized natural rubber by colloidal filler such as silica or carbon black, in order to (ENR) and hydroxyls of silicic acid, but without attempting improve their mechanical properties. The reaction kinetics of tetrasulfide (TESPT) are commonly used to enhance mixtures of highly dispersible silica (HD) with a liquid compatibility of nonpolar rubbers with silica and improve hydroxylated polybutadiene epoxidized at 8.8 mol% mechanical properties of silica-filled elastomers, since such (EpLHPB) was studied through isothermal experiments in coupling agents are capable of establishing covalent bonds DSC, from which it is possible to evaluate autocatalytic and between polymer chains and silica surface[1,2]. Materials and Methods ensure a sufficient silanization rate, while avoiding the risk of scorch Because of such difficulties, rubber compounds 2.1 Materials containing silica in a high content often require the use of specially-designed mixers and three or more mixing stages[3,4]. The epoxy content was determined by 1H NMR (300 MHz, CDCl3)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
