DLP 4D‐Printing of Remotely, Modularly, and Selectively Controllable Shape Memory Polymer Nanocomposites Embedding Carbon Nanotubes

• Published in: Advanced functional materials Vol. 31; no. 50
• Main Authors: Cortés, Alejandro, Cosola, Andrea, Sangermano, Marco, Campo, Mónica, González Prolongo, Silvia, Pirri, Candido Fabrizio, Jiménez‐Suárez, Alberto, Chiappone, Annalisa
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc 01-12-2021
• Subjects: 4D printing; Activated carbon; carbon nanotubes; digital light processing; Electrical measurement; Electrical resistivity; Electronic devices; electro‐activated composites, shape memory polymer; Embedding; Materials science; Multi wall carbon nanotubes; Nanocomposites; Ohmic dissipation; Polyethylene glycol; Polyhydroxyethyl methacrylate; Polymer matrix composites; Polymers; Recovery; Resistance heating; Rheological properties; Shape memory; Thermomechanical properties; Three dimensional printing
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.202106774

An in‐depth investigation on novel electro‐activated shape memory polymer composites (SMPCs) for digital light processing 3D‐Printing, consisting of a poly(ethylene glycol) diacrylate/poly(hydroxyethyl methacrylate) matrix embedding multi‐walled carbon nanotubes (CNTs), is reported here. The composition of the photocurable (meth)acrylate system is finely tuned to tailor the thermomechanical properties of the matrix, whereas the effect of CNTs on the photoreactivity and rheological properties of the formulations is investigated to assess the printability. Electrical measurements confirmed that the incorporation of CNT into the polymeric matrix enables the electrical conductivity and thus the possibility to remotely heat the nanocomposite using the Joule effect. The feasibility to drive a shape memory cycle via Joule heating is proved, given that the high shape fixity (Rf) and shape recovery (Rr) ratios achieved (Rf ≈ 100%, Rr > 95%) confirmed the significant electrically‐triggered responsiveness of such CNT/SMPCs. Finally, it is shown how to activate a modular and selective electro‐activated shape recovery, which may ultimately envisage the 4D‐Printing of remotely and selectively controllable smart devices.
Novel electro‐activated shape memory polymer composites consisting of a poly(ethylene glycol) diacrylate/poly(hydroxyethyl methacrylate) thermosetting matrix embedding carbon nanotubes (CNTs) are successfully prepared by digital light processing 3D‐printing. The presence of CNTs enables remote activation of a shape memory cycle via Joule heating (Rf ≈ 100%, Rr > 95%), envisaging the 4D‐Printing of remotely and selectively controllable smart devices.