Spider silks mechanics: predicting humidity and temperature effects

TL;DR

This paper presents a microstructure-inspired model to predict how humidity and temperature variations affect the mechanical behavior of spider silks, emphasizing the role of water molecules in altering crosslinking and macromolecular configurations.

Contribution

The study introduces a novel microstructure-based model that accurately predicts humidity and temperature effects on spider silk mechanics, linking molecular interactions to macroscopic responses.

Findings

Model quantitatively reproduces experimental data

Water molecules reduce crosslinking in soft regions

Temperature and humidity significantly influence mechanical response

Abstract

We deduce a microstructure inspired model for humidity and temperature effects on the mechanical response of spider silks, modelled as a composite material with a hard crystalline and a soft amorphous region. Water molecules decrease the percentage of crosslinks in the softer region inducing a variation of natural configuration of the macromolecules. The resulting kinematic incompatibility between the regions crucially influences the final mechanical response. We demonstrate the predictivity of the model by quantitatively reproducing the experimentally observed behavior