EFFECT OF PHOTO ACCELERATORS ON THE DEGRADATION OF POLYSTYRENE FOAM WASTE
Keywords:
Polystyrene foam waste, photodegradation, accelerators, mathematical modellingAbstract
The Polystyrene (PS) foam has been widely used as food packaging and insulators. The former application has been commonly seen as take-away meal boxes. When it reaches the end-users, it would be discarded as municipal solid waste (MSWs). It would readily undergo photodegradation if it was disposed in the open-air dumping. It would take months to be degraded in the natural condition. In the present study, the degradation rate of the PS-foam in open-air dumping and in the artificial exposure, using Standard weatherometer, was investigated. Benzoyl peroxide and AIBN were used as photo accelerators. The concentration of these chemicals varied from 1% to 3% by weight. The decrease in the number average molecular weight of the samples, characterised by GPC technique, was monitored and used to calculate the reaction rate. By using the degradation rate mathematical modelling the order of reaction (b), rate constant ( ) and the half-life (t1/2) of the photo reactions were obtained. The results showed that the b was increased with the increase of concentration of the accelerators. Likewise, the decreased. However, by considering the t1/2 it was found that the half life of photo reaction using peroxide as the accelerator slightly decreased when the concentration increased from 1% to 3%. Nevertheless, the value decreased significantly when the AIBN was employed.
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