Polyelectrolyte Polypeptide Scaling Laws Via Mechanical and Dielectric Relaxation Measurements

TL;DR

This study compares mechanical and dielectric relaxation measurements of polyelectrolyte polypeptides to theoretical scaling laws, revealing how different methods inform on polymer chain conformation in hydrogels and solutions.

Contribution

It demonstrates that mechanical and dielectric relaxation measurements can both reveal polymer chain conformations, aligning with theoretical scaling laws for different polymer states.

Findings

Viscoelastic relaxation scaled with concentration according to reptation dynamics.

Dielectric relaxation scaled with concentration as an ideal or extended chain.

Different measurement methods provide complementary insights into polymer conformation.

Abstract

Experimental results from mechanical viscoelastic as well as dielectric relaxation times were compared to theoretical expectations utilizing polymer scaling theory. Viscoelastic relaxation of a hydrogel at 33% relative humidity fabricated from co-poly-L-(glutamic acid$_{4}$, tyrosine$_{1}$) [PLEY(4:1)] crosslinked with poly-L-lysine scaled with concentration according to reptation dynamics. High frequency dielectric relaxation of aqueous copolymer PLEY(4:1) scaled with concentration as an ideal chain and aqueous Poly-L-glutamic acid scaled as an extended chain. The study shows that two seemingly different measurement methods can yield information about the state of polymer chain conformation in situ.