KINETICS AND COOLING TEMPERATURE EFFECT OF THE ...

In this study attempt was made to produce useful items from disposed polystyrene by modification with heat. Heat-modified polystyrene obtained by cooling the polymer melt at 285K, 303 K, 313K, 353K, 373K and 423K, were subjected to analysis to determine their ability to transfer some of their organic composition into saliva and sweat. The extents of material transfer and kinetics of the transfer process were determined. The research revealed that polystyrene waste can be recycled by heat application into useful products. And the products can transfer some of its material (organic) composition into saliva and sweat at 37 oC. It was observed that more materials are transferred into saliva than in sweat, and at equilibrium, the difference in the amount of materials transferred is 13.16%. Bio-dissolved compounds from the heat-modified polystyrene in the body fluids increased with increase in cooling temperature. In addition, the transfer of materials from the heat-modified polymer into saliva or sweat follows pseudo second order kinetic model at 37 oC, and the initial transfer rate was noted to be higher for saliva (1.916x10-6 mgC/g.min) than in sweat (1.654x10-6 mgC/g.min). But the rate constants and equilibrium concentrations were, 4.105min-1 and 6.832x10-4 mgC/g, as well as 4.761min-1 and 5.894x10-4 mgC/g for saliva and sweat respectively. More than 25% of all transferrable materials from the recycled polystyrene is transferred in to the body fluids in 30 minutes.