Phantom chain simulations for fracture of star polymer networks on the effect of arm molecular weight

Fuente: arXiv
Saved in:
Bibliographic Details
Main Author: Masubuchi, Yuichi
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866912860334981120
author Masubuchi, Yuichi
author_facet Masubuchi, Yuichi
contents This study investigated the fracture of star polymer networks made from prepolymers with various arm molecular weights in the range $2 \leq N_a \leq 0$, for node functionalities $3 \leq f \leq 8$ and conversion ratios $0.6\leqϕ_c\leq0.95$ by phantom chain simulations. The networks were created via end-linking reactions of star polymers dispersed in a simulation box with a fixed monomer density $ρ=8$. The resultant networks were alternatively subjected to energy minimization and uniaxial stretch until the break. The stretch at the break, $λ_b$, depended on the strand molecular weight $N_s=2N_a+1$ with a power-law manner described as $λ_b \sim N_s^0.67$, consistent with the experiment. However, the strand length before stretch is proportional to $N_s^0.5$, which does not explain the observed N_s-dependence of $λ_b$. The analysis based on the non-affine deformation theory does not interpret the phenomenon either. Instead, the increase of normalized prepolymer concentration concerning the overlapping concentration with increasing $N_s$ explains the result through a rise in the fraction of broken strands.
format Preprint
id arxiv_https___arxiv_org_abs_2408_14058
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Phantom chain simulations for fracture of star polymer networks on the effect of arm molecular weight
Masubuchi, Yuichi
Soft Condensed Matter
This study investigated the fracture of star polymer networks made from prepolymers with various arm molecular weights in the range $2 \leq N_a \leq 0$, for node functionalities $3 \leq f \leq 8$ and conversion ratios $0.6\leqϕ_c\leq0.95$ by phantom chain simulations. The networks were created via end-linking reactions of star polymers dispersed in a simulation box with a fixed monomer density $ρ=8$. The resultant networks were alternatively subjected to energy minimization and uniaxial stretch until the break. The stretch at the break, $λ_b$, depended on the strand molecular weight $N_s=2N_a+1$ with a power-law manner described as $λ_b \sim N_s^0.67$, consistent with the experiment. However, the strand length before stretch is proportional to $N_s^0.5$, which does not explain the observed N_s-dependence of $λ_b$. The analysis based on the non-affine deformation theory does not interpret the phenomenon either. Instead, the increase of normalized prepolymer concentration concerning the overlapping concentration with increasing $N_s$ explains the result through a rise in the fraction of broken strands.
title Phantom chain simulations for fracture of star polymer networks on the effect of arm molecular weight
topic Soft Condensed Matter
url https://arxiv.org/abs/2408.14058