Sulphonation of Expanded Polystyrene Waste Under Microwave Irradiation.

Chemical modification of polymeric materials is one way of polymer waste management. In our study, expanded polystyrene waste (EPS), used as the reference material, was converted into polymeric flocculants by the sulphonation reaction. Thus, poly(styrenesulphonate) acids (EPSS) were obtained from EPS during the sulphonation process with sulphuric acid as the sulphonation agent and Ag₂SO₄ as the catalyst under both conventional heating and microwave conditions. At the termination of the process the products were precipitated in the form of sodium salts (NaEPSS) in the reaction with Na₂CO₃ and their characteristics were given. The influence of temperature and time of reaction on the properties of EPSS and NaEPSS was studied and compared with conventional and microwave conditions. The results showed that the sulphonation process performed under microwave irradiation allowed us to receive products with properties similar to the ones obtained under conventional conditions but the reaction time was substantially reduced from 1 and ½ hour to 15 min. [ABSTRACT FROM AUTHOR]