The Impact of Technology on Poisson’s Ratio of Auxetic Polyurethane Foams

Abstract

The article presents a method for measuring Poisson’s ratio of the polyurethane foam, including shapes of the auxetic foam. The impact of technology applied in Air Force Institute of Technology, that is a method for processing the selected polyurethane foams, on the value of Poisson’s ratio of the auxetic foam shape was presented. In order to manufacture the auxetic foam shapes, two methods; mechanical-thermal and mechanical-chemical-thermal, were applied.

Auxetic materials and structures for potential defense applications: An overview and recent developments

“…However, in considering the safety hazard and environmental footprint issues, such a chemical softening process is not recommended in further research. 121 3D and four-dimensional (4D) printing methodology. Apart from traditional methodologies to convert foam materials into auxetic foam materials, one novel way of introducing repeatability into the auxetic foam fabrication process is through the employment of 3D printing technologies in an additive manufacturing technique.…”

“…However, in considering the safety hazard and environmental footprint issues, such a chemical softening process is not recommended in further research. 121…”

Manufacturing, characteristics and applications of auxetic foams: A state-of-the-art review

“…Inspired by this novel softening process, an improved chemomechanical methodology (the Mechanic-Chemic-Thermal technique) (Figure . 6) was then developed by the Air Force Institute of Technology (AFIT) in Poland [51]. Compared with foams fabricated using the original thermo-mechanical methodology [52], auxetic foams softened by chemical process could obtain a lower Poisson's ratio without the risk of uneven heating, and this approach is potential to produce large samples, however in considering of the safety hazard and environmental footprint issues, such chemical softening process is not recommended in further researches. For developing a more environment-friendly fabrication process, Li [53] [54] and [36]).…”