Abstract:
Polystyrene/waste tires composites were prepared in this study by incorporating shredded waste tires into polydisperse polystyrene in a melt-mixing method. The dynamic mechanical properties of PS and PS/composite have been evaluated and compared. These properties were studied using ARES-Rheometer under nitrogen atmosphere in parallel plate geometry with diameter 8 mm. The measurements are carried out over a wide range of temperatures ranged from 120°C to 220°C and frequencies from 100 to 0.1 radians per second. The shear creep stress J(t) and loss factor were studied and compared with those of unfilled PS. The dynamic mechanical properties and stability at elevated temperatures were found to increase with the addition of waste tires to PS as confirmed by the results.
From the results, the value of J(t) modulus for PS/waste tire is higher than this for the original material of PS. The incorporation of the rubber to the PS changes the value of J(t) at 0.001 second from 5.6´10-6 to 3.7´10-6 Pa-1 for PS and PS/waste tire, respectively and this difference increases with time. This confirmed that PS/waste tire composite exhibits higher stability at 180°C for a long time than the original unfilled PS. At frequency w = 6.7´102 radians/s , the value of tand increases about 20% by the incorporation of the rubber filler, due to the increase in the G'' modulus particularly at low frequencies in the flow regime.
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