TG/FTIR analysis on co-pyrolysis behavior of PE, PVC and PS

- The thermal stability increased flowed by PVC, PS and PE.
- The pyrolysis process of PE was accelerated when mixed with PS.
- Both PE and PVC were postponed when mixed together and PS was postponed when mixed with PVC.
- Dechloridation of PVC simultaneously with cyclization of conjugated polyene could produce dioxin.

The pyrolysis and co-pyrolysis behaviors of polyethylene (PE), polystyrene (PS) and polyvinyl chloride (PVC) under N2 atmosphere were analyzed by Thermal gravimetric/Fourier transform infrared (TG/FTIR). The volatile products were analyzed to investigate the interaction of the plastic blends during the thermal decomposition process. The TGA results showed that the thermal stability increased followed by PVC, PS and PE. The pyrolysis process of PE was enhanced when mixed with PS. However, PS was postponed when mixed with PVC. As for PE and PVC, mutual block was happened when mixed together. The FTIR results showed that the free radical of the decomposition could combine into a stable compound. When PE mixed with PVC or PS, large amount of unsaturated hydrocarbon groups existed in products while the content of alkynes was decreased. The methyl (CH3) and methylene (CH2) bonds were disappeared while PVC mixed with PE.