Poisson's ratio and volume change accompanying deformation of randomly oriented electrospun nanofibrous membranes

ABSTRACT

The present work focuses on the determination of volume change accompanying deformation and Poisson's ratio for electrospun nanofibrous membranes. For this purpose, polyurethane (PU) is considered for the fabrication of electrospun nanofibrous membranes. Three different sample thicknesses are fabricated. Following this, surface morphology analysis and fibre orientation analysis are conducted to investigate the variation of properties between electrospun PU membranes of different thicknesses. Subsequently, PU specimens are subjected to uniaxial extension test where the changes in sample width and thickness are recorded as a function of applied strain. Volume changes are computed while further analysis on the relationship between transverse strains and axial strain provided the values of Poisson's ratio. For all three electrospun PU samples investigated, significant volume changes are observed while the in-plane Poisson's ratio is found to be around 0.55. However, the out-of-plane Poisson's ratio of electrospun PU membranes are not classical and remains undetermined.

KEYWORDS:

• Poisson’s ratio
• nanofiber
• membrane
• volume change
• mechanical response
• electrospinning
• polyurethane
• randomly oriented

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The authors greatly appreciate the financial support from Frontier Research Grant (FRG) FG010-17AFR, University of Malaya Research Grant (UMRG) RP034C-15AET and RP034E-15AET, Fundamental Research Grant Scheme (FRGS) FP048-2013B, Postgraduate Research Fund (PPP) PG113-2015A, Embassy of France in Malaysia and from the Ministry of Research, Technology and Higher Education of Indonesia through World Class Professor (WCP) Program.