2134/33961
Stavros Drakopoulos
Stavros
Drakopoulos
Georgios C. Psarras
Georgios C.
Psarras
Giuseppe Forte
Giuseppe
Forte
Ignacio Martin-Fabiani
Ignacio
Martin-Fabiani
Sara Ronca
Sara
Ronca
Entanglement dynamics in ultra-high molecular weight polyethylene as revealed by dielectric spectroscopy
Loughborough University
2018
Ultra-high molecular weight polyethylene
Entanglement formation
Broadband dielectric spectroscopy
Materials Engineering not elsewhere classified
2018-07-17 14:35:00
Journal contribution
https://repository.lboro.ac.uk/articles/journal_contribution/Entanglement_dynamics_in_ultra-high_molecular_weight_polyethylene_as_revealed_by_dielectric_spectroscopy/9234788
With the help of Broadband Dielectric Spectroscopy, it has been possible to study the molecular dynamics of disentangled Ultra High Molecular Weight Polyethylene in a wide temperature and frequency range. Catalytic ashes of aluminum oxide act as dielectric probes, allowing the identification of five different processes: an αc-process due to movements in the crystalline phase, two γ-processes attributed to amorphous chain portions close to the crystalline lamellae, and two β-processes that we have attributed to the disentangled and entangled amorphous phases. The entanglement formation has been followed by isothermal runs and a model that predicts the energy spent to form entanglements as a function of time and temperature is thereby proposed. This model allowed us to calculate the associated activation energy of the entanglement process. Our work advances further the understanding of entanglement dynamics of ultra-high molecular weight polymers, and the proposed model could prove useful to describe other similar processes such as cross-linking.