Polymer nanocomposites incorporating electrically conductive nanostructured fillers are increasingly investigated as multifunctional materials capable of addressing functional requirements across a broad range of applications, from biomedical devices to industrial load-bearing materials and structures. Recent studies have suggested that this class of nanocomposites can be designed to exhibit electrically activated healing, restoring electrical percolation and mechanical integrity. This research focuses on this peculiar self-healing process, evaluating both its general applicability, even to polymers whose molecular structures were not designed to be "healed", and its effectiveness in restoring electrical, mechanical, and structural continuity in polymer nanocomposites. The restoration occurs through a sort of migration of nanoparticles with attached polymer chains toward the damaged region, thereby restoring the functional and molecular nanocomposite architecture. The electric-field-assisted nanofiller redistribution in the damaged region following restoration is experimentally verified by Tunneling Atomic Force Microscopy (AFM-TUNA). The recovery of the mechanical integrity of the polymer nanocomposites after the electro-healing process is further evaluated through dedicated airtightness tests performed before and after damage and subsequent healing. To enable electro-healing, multiwalled carbon nanotubes (MWCNTs) were used as conductive nanofillers. Three polymer matrices, poly(ethylene-co-methacrylic acid) (EMAAc), thermoplastic vulcanizate polypropylene (TVPP), and acrylonitrile butadiene styrene (ABS), were selected to investigate the generality of electro-healing behavior and to assess its potential applicability across diverse material systems and application fields. The results highlight that electro-healing can repair damage initiation up to spatial scales of micrometers or several millimeters and can be successfully applied to load-bearing composite structures.
Electro-healing of polymeric nanocomposites via damage-driven particle migration
Guadagno L.;Vertuccio L.;Longo R.;Raimondo M.;Pantani R.;Aliberti F.
In corso di stampa
Abstract
Polymer nanocomposites incorporating electrically conductive nanostructured fillers are increasingly investigated as multifunctional materials capable of addressing functional requirements across a broad range of applications, from biomedical devices to industrial load-bearing materials and structures. Recent studies have suggested that this class of nanocomposites can be designed to exhibit electrically activated healing, restoring electrical percolation and mechanical integrity. This research focuses on this peculiar self-healing process, evaluating both its general applicability, even to polymers whose molecular structures were not designed to be "healed", and its effectiveness in restoring electrical, mechanical, and structural continuity in polymer nanocomposites. The restoration occurs through a sort of migration of nanoparticles with attached polymer chains toward the damaged region, thereby restoring the functional and molecular nanocomposite architecture. The electric-field-assisted nanofiller redistribution in the damaged region following restoration is experimentally verified by Tunneling Atomic Force Microscopy (AFM-TUNA). The recovery of the mechanical integrity of the polymer nanocomposites after the electro-healing process is further evaluated through dedicated airtightness tests performed before and after damage and subsequent healing. To enable electro-healing, multiwalled carbon nanotubes (MWCNTs) were used as conductive nanofillers. Three polymer matrices, poly(ethylene-co-methacrylic acid) (EMAAc), thermoplastic vulcanizate polypropylene (TVPP), and acrylonitrile butadiene styrene (ABS), were selected to investigate the generality of electro-healing behavior and to assess its potential applicability across diverse material systems and application fields. The results highlight that electro-healing can repair damage initiation up to spatial scales of micrometers or several millimeters and can be successfully applied to load-bearing composite structures.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
