| 초록 |
The development of thermoplastic vulcanizate (TPV) from waste ground rubber tire powder with PP and PE was investigated by processing in a co-rotating twin-screw extruder equipped with well-designed screw configuration. The blends containing dispersed phase of rubber vulcanizate powder (obtained from waste tires) in a plastic matrix were studied. The mechanical properties, rheological properties and morphology were analysed to evaluate the effect of compatibilizers such as styrene-ethylene-butylene-styrene (SEBS) and maleic anhydride grafted SEBS (SEBS-MA) and the effect of dynamic reaction on the waste rubber blends. Under optimal conditions of miscible blending, the mechanical properties of the blends were improved in comparison with the immiscible blends. In model material/polypropylene blends, AFM studies revealed the development of interfacial layers, interfacial roughening and improved interfacial adhesion between model material and polypropylene phases due to the formation of in-situ copolymer at the interfaces , leading to the improved properties of model material/polypropylene blends. In the present work, waste tire rubber powder has been modified using ultraviolet energy (UV) in the presence of active monomer like allylamine. The modified rubber powders were then characterized with Fourier Transform InfraRed spectroscopy (FTIR), Scanning electron microscopy (SEM)/Energy dispersive X-ray analysis, thermogravimetric analysis (TGA) and surface energy measurements by dynamic wicking method. The modified rubber powders were then incorporated in the polypropylene matrix and its influence on the mechanical properties of the PP/waste ground rubber tire powder blend have been studied extensively in terms of UV radiation time, rubber powder loading and allylamine concentration. In these studies, a constant weight percentage (50wt %) of maleic anhydride grafted polypropylene (PP-g-MA) relative to weight percentage of waste rubber powder has been added as a compatibilizer. Chemical interaction between the UV modified waste ground rubber tire powder and polypropylene matrix have been characterized with X-ray diffraction. The surface grafting of allylamine on the rubber powder by means of chemical methods involving benzoyl peroxide and its role on the mechanical properties of the blend have been investigated. Development of a thermoplastic vulcanizate by a continuos blending process by dynamic reaction of TPE and modification of rubber powder are expected. |
