# Structure-property relationships via recovery rheology in viscoelastic materials

## TL;DR

This study links recoverable strain to microstructure evolution in viscoelastic materials using SANS and rheology, revealing detailed structure-property relationships and stress behaviors under large amplitude oscillatory shear.

## Contribution

It introduces a new understanding of how recoverable strain correlates with microstructural changes and stress evolution in viscoelastic materials during LAOS.

## Key findings

- Recoverable strain correlates with microstructure evolution.
- Stress responses are dictated by recoverable strain.
- LAOS responses contain information from both steady-state and linear regimes.

## Abstract

The recoverable strain is shown to correlate to the temporal evolution of microstructure via time-resolved small-angle neutron scattering (SANS) and dynamic shear rheology. Investigating two distinct polymeric materials of wormlike micelles and fibrin network, we demonstrate that, in addition to the nonlinear structure-property relationships, the shear and normal stress evolution is dictated by the recoverable strain. A distinct sequence of physical processes under large amplitude oscillatory shear (LAOS) is identified that clearly contains information regarding both the steady-state flow curve and the linear-regime frequency sweep, contrary to most interpretations that LAOS responses are either distinct from, or somehow intermediate between the two cases. This work provides a physically-motivated and straightforward path to further explore the structure-property relationships of viscoelastic materials under dynamic flow conditions.