On the signature of tensile blobs in the scattering function of a stretched polymer

TL;DR

This paper uses Monte Carlo simulations to analyze how tensile blobs influence the scattering function of a stretched polymer, confirming Pincus's scaling prediction within blobs and describing scattering behavior outside blobs.

Contribution

First simulation-based verification of Pincus scaling prediction for tensile blobs in a stretched polymer's scattering function.

Findings

Identification of crossover in scattering function due to tensile blobs

Validation of Pincus scaling prediction inside blobs

Debye function describes scattering outside blobs

Abstract

We present Monte Carlo data for a linear chain with excluded volume subjected to a uniform stretching. Simulation of long chains (up to 6000 beads) at high stretching allows us to observe the signature of tensile blobs as a crossover in the scaling behavior of the chain scattering function for wave vectors perpendicular to stretching. These results and corresponding ones in the stretching direction allow us to verify for the first time Pincus prediction on scaling inside blobs. Outside blobs, the scattering function is well described by the Debye function for a stretched ideal chain.