title: Structure-induced nonlinear viscoelasticity of non-woven fibrous matrices.
abstract: Fibrous materials are widely utilized as tissue engineering scaffolds for tissue regeneration and other bioengineering applications. The structural as well as mechanical characteristics of the fibrous matrices under static and dynamic mechanical loading conditions influence the response of the cells. In this paper, we study the mechanical response of the non-woven fibrous matrices under oscillatory loading conditions and its dependence on the structural properties of fibrous matrix. We demonstrate that under oscillatory shear and elongation, the fibrous matrices demonstrate nonlinear viscoelasticity at all strain amplitudes. This is contrary to the behavior of other soft polymeric materials for which nonlinearity in the viscoelastic response vanishes for small strains. These observations suggest that despite their prevalence, the measures of linear viscoelasticity (e.g., storage and loss moduli) are inadequate for the general description of the viscoelastic nature of the fibrous materials. It was, however, found that linear viscoelastic nature of fibrous matrices for small amplitudes is restored when a pre-stretch is applied to the fibrous matrix along with oscillatory strains. Further, we also explored the influence of the structural properties of the fibrous matrices (fiber orientation, alignment and curvature) on their viscoelastic nature.
authors.affiliation: Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Kanpur, 208016, India.
authors.forename: Mohd Suhail
authors.initials: MS
authors.lastname: Rizvi
authors.affiliation: Department of Biological Sciences and Bioengineering, Indian Institute of Technology Kanpur, Kanpur, 208016, India.
authors.forename: Anupam
authors.initials: A
authors.lastname: Pal
authors.affiliation: Mechanics and Applied Mathematics Group, Department of Mechanical Engineering, Indian Institute of Technology Kanpur, Kanpur, 208016, India. sovandas@iitk.ac.in.
authors.forename: Sovan Lal
authors.initials: SL
authors.lastname: Das
mesh_terms: D005583:Fourier Analysis; D008954:Models, Biological; D017711:Nonlinear Dynamics; D012212:Rheology; D013314:Stress, Mechanical; D054457:Tissue Scaffolds / Q000737:chemistry*; D014783:Viscosity
keywords: Dynamic mechanical analysis; Fibrous biomaterials; Nonlinear viscoelasticity; Storage and loss moduli