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Thermal behavior and pyrolytic degradation kinetics of polymeric mixtures from waste packaging plastics

“…The eventual discrepancy between the experimental and reconstructed parameters was used to establish if interaction among the polymer components is found or not when degradation takes place. Some authors agree that PS appears to be responsible for the shift of TG curves of polyolefins towards lower degradation temperature when mixed together, while PS itself seems to be stabilized or unaltered [24,43,44]. The mixing effect on the rate of degradation was interpreted in terms of an intermolecular radical transfer between different polymer radicals; Miranda et al [24] suggest that intermolecular hydrogen transfer could be the predominant reaction path.…”

“…Looking carefully at the literature findings, the thermal degradation kinetics of plastic waste or virgin mixtures has not sufficiently been developed. Only few studies [24,26,43,44,51] reported the E a values for degradation of polymer mixtures, by assuming that the reaction rate is affected by the interactions among the polymer components. In particular, Miranda et al [24] found that the difference between [43,44].…”

“…Only few studies [24,26,43,44,51] reported the E a values for degradation of polymer mixtures, by assuming that the reaction rate is affected by the interactions among the polymer components. In particular, Miranda et al [24] found that the difference between [43,44]. By observing the non-negligible variation of activation energy with the extent of conversion for the second degradation step of CPCPW2 and CPCPW3 as well as for degradation step of CPCPW1 (Figure 8b), it has been decided to apply even the most accurate method developed by Vyazovkin: the modified isoconversional method [38].…”

Comparative study of pyrolytic decomposition of polymers alone or in EVA/PS, EVA/PVC and EVA/cellulose mixtures

“…In Europe there is currently rising interest in biomethanization, pyrolysis and vitrification processes as alternatives to incineration. Murata and Makino [1] studied the pyrolysis of mixtures of PE, PS, PP and noted that these polymers interact only slightly. Knuemann and Bockhorn [2] found no significant influence of PVC on PE, PS and PP, except with PA. We chose to investigate the degradation under pyrolysis conditions of binary mixtures of polymers in which one of the components is EVA.…”

Hydrothermal Cracking of Polyethylene, Polypropylene, and/or Polystyrene Mixtures under Supercritical Water Condition

“…(2) The mechanism of attack of radicals on the plastics, which are more hardly decomposed, in the mixed treatment is effective no matter whether the cracking mechanism of these plastics is random scission or depolymerization at the end of main chain. (3) In mixed treatment, the main mechanism of degradation for each plastic is the same as that in separate treatment, so that the main composition of oily product in mixing treatment is similar to that of the mixture of oily products in each separate treatment. But some new materials were also found in the oily product.…”