Recovery of Polystyrene from Waste Food Containers

In this study, we aim to verify through experiments whether commercial waste polystyrene food containers can be recycled. To extract polystyrene from waste food containers, they are first dissolved in THF and then precipitated in methanol. Subsequently, the polystyrene is recovered in powder form through filtration and drying processes. The polystyrene is then placed in a molding plate and pressed into dog-bone shaped samples. Additionally, the thermal properties of the recovered polystyrene are measured using DSC, and the molecular weight and molecular weight distribution are determined using GPC. The DSC results show that the glass transition temperature of most recovered polystyrene samples is measured around 100℃. However, the container used for cup ramen is measured at 87.3℃, likely due to its lower molecular weight of 59,000 g/mol. The GPC measurements of other samples reveal that the molecular weight of commercially available polystyrene ranges from 64,000 g/mol to 93,000 g/mol. In conclusion, waste polystyrene can be quantitatively recycled through the dissolution process.