Next Article in Journal
A Novel Strategy to Achieve Enhanced Reinforcement and Decreased Damping in CNT-Nanocomposites
Previous Article in Journal
Characterization of Electrospun PVDF Fibres for Sensing and Actuation
Article Menu
Issue 8 (ICEM 2018) cover image

Article Versions

Export Article

Open AccessProceedings
Proceedings 2018, 2(8), 486;

Auxetic Films with a Miniaturized Cellular Structure

Engineering Department, University of Rome, Roma Tre, 00146 Rome, Italy
Presented at the 18th International Conference on Experimental Mechanics (ICEM18), Brussels, Belgium, 1–5 July 2018.
Author to whom correspondence should be addressed.
Published: 28 June 2018
PDF [337 KB, uploaded 21 August 2018]


Auxetic materials represent a relatively new class of materials that are characterized by a cellular structure and a negative Poisson coefficient. Auxetics are extremely useful for morphing applications thanks to their synclastic deformation capability. Most of these materials have been developed with macro-scaled cellular units. However there are some applications (e.g., micro-air vehicles or biomedical applications) for which polymeric morphing materials need to be applied in relatively small areas. In these cases, a material scale reduction that leads to lightweight auxetic films with a miniaturized cellular structure could be of great interest. With this in mind, an experimental study was conducted to analyze the response of films that are characterized by a miniaturized cellular structure. The unit cells in this study were made of an aggregation of microwires and micronodes that were strategically interconnected to form auxetic expansions and contractions. The reduction in scale of the cellular units has a significant impact on the material characterization and properties. The response of polymeric micro-scaled cells is in fact here demonstrated to be strongly influenced by surface forces and dramatic changes in gaseous or liquid environment. This represents the most critical aspect and key variation when comparing these films with standard macro-auxetics. The extremely challenging (at this length-scale) fabrication and testing processes were optimized. Single cells, were thus successfully tested in different environments with programmed and digital micro-stages while being monitored under a microscope with a video camera. Digital image correlation techniques were used to highlight the deformation. The expansion/contraction process was found to be fully reversible after several cycles and at different deformation speeds.
Keywords: cellular structure; auxetic; polymer cellular structure; auxetic; polymer
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).

Share & Cite This Article

MDPI and ACS Style

Chen, Y.; Lanzara, G. Auxetic Films with a Miniaturized Cellular Structure. Proceedings 2018, 2, 486.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Metrics

Article Access Statistics



[Return to top]
Proceedings EISSN 2504-3900 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top