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Waste tire rubber is commonly recycled by blending with other polymers. However, the mechanical properties of these blends were poor due to lack of adhesion between the matrix and the waste tire rubber. In this research, the use of electron beam irradiation and (3-Aminopropyl)triethoxy silane (APTES) on enhancing the performance of 50 wt% reclaimed tire rubber (RTR) blend with 50 wt% poly(ethylene-co-vinyl acetate) (EVA) was investigated. Preparation of RTR/EVA blends were carried out in the internal mixer. The blends were then exposed to electron beam (EB) irradiation at doses ranging from 50 to 200 kGy. APTES loading was varied between 1 to 10 wt%. The processing, morphological, mechanical, and calorimetric properties of the blends were investigated. The stabilization torque and total mixing energy was higher in compatibilized blends. Mechanical properties of RTR/EVA blends were improved due to efficiency of APTES in further reclaiming the RTR and compatibilizing the blends. APTES improved the dispersion of embedded smaller RTR particles in EVA matrix and crosslinking efficiency of the blends. Calorimetric studies showed increased crystallinity in compatibilized blends which corresponds to improved mechanical properties. However, the ductility of the blend was decreased due to increased interaction between EVA and APTES. Presence of APTES increased the efficiency of electron beam irradiation induced crosslinking which was shown through gel content analysis and Charlesby-Pinner equation. [ABSTRACT FROM AUTHOR]

In an attempt to maximize the beneficial effect of irradiation, the influence of multifunctional acrylates (MFAs) such as trimethylol propane triacrylate, ethylene glycol dimethacrylate, trimethylol propane trimethacrylate, and tripropylene glycol diacrylate on the 90/10 ethylene vinyl acetate/waste tire dust (EVA/WTD) were studied. The 90/10 EVA/WTD and EVA-containing 4 phr MFA prepared using a Haake mixer at 140°C and 50 r min−1 rotor speed. The blends were then irradiated using a 3.0-MeV electron beam machine. Results on gel fraction revealed that EVA/WTD blends were cross-linked by electron beam irradiation. Among the MFA employed in this studies, TPGDA was found to render highest tensile strength with the best retention in elongation at break and increased heat of fusion and crystallinity of blends upon irradiation. The changes in the properties of EVA/WTD blends upon irradiation are attributed to the cross-linking of the EVA matrix. The changes in crystallinity and crystalline melting temperatures of EVA/WTD blends upon irradiation are discussed in detail. [ABSTRACT FROM AUTHOR]

Blends of low-density polyethylene, LDPE /waste tire dust, WTD were prepared by using a Haake mixer at 100/0, 90/10, 80/20, 70/30, and 60/40 blend ratios. The blends were irradiated by using a 3.0 MeV electron beam (EB) machine at 0, 50, 100, 150 and 200 kGy irradiation doses. All the samples were tested for mechanical properties such as tensile strength, elongation at break, modulus at 100% strain, hardness and impact strength before and after irradiation exposure. Prior to irradiation, the mechanical properties of the blends (except for impact strength) found to show a gradual decrease with the addition of WTD. Enhancements in the mechanical properties were achieved upon EB irradiation of the LDPE/WTD blends. This is attributed to the irradiation induced crosslinking of LDPE matrix along with the increase in the compatibility of LDPE/WTD blend through irradiation-induced co crosslinking between the WTD and LDPE at the interface. The gel fraction results and scanning electron micrographs of the fracture surfaces of the LDPE/WTD blends show evidences consistent with the above contention. [ABSTRACT FROM AUTHOR]

ABSTRACT Scrap rubber reclamation is one of the most desirable approaches to solve the disposal problem of used tires. However, reclaimed tire rubber (RTR) has not gained enough attention due to its poor properties. In this work, the effects of poly(ethylene- co-vinyl acetate) (EVA) addition and electron beam (EB) irradiation on the properties of RTR were studied. The RTR/EVA blends containing 100-0 wt % of RTR were prepared in the internal mixer followed by EB irradiation with doses ranging from 50 to 200 kGy. The RTR/EVA blends were subjected to mechanical, gel content, thermal, and morphological analysis. It was found that the addition of EVA to RTR improved the mechanical properties of RTR. However, results revealed that RTR undergoes irradiation-induced crosslinking in a relatively lesser extent as compared to EVA. This observation is associated with the stabilization and radical scavenging effects of additives, which are present in the RTR matrix. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41649. [ABSTRACT FROM AUTHOR]