Saved in:
Bibliographic Details
Main Authors: Street, Aidan, Mistry, Devesh, Mattsson, Johan, Gleeson, Helen F.
Format: Preprint
Published: 2025
Subjects:
Online Access:https://arxiv.org/abs/2507.07639
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866909682727124992
author Street, Aidan
Mistry, Devesh
Mattsson, Johan
Gleeson, Helen F.
author_facet Street, Aidan
Mistry, Devesh
Mattsson, Johan
Gleeson, Helen F.
contents Elastomeric pressure-sensitive adhesives (PSAs) form adhesive bonds under light pressure. Liquid crystal elastomers (LCEs) are exciting PSA candidates as they can impart both anisotropy and temperature-dependence to adhesion, but the full potential of their anisotropic adhesion is unexplored. Here, identical side-chain LCEs, produced as transparent isotropic or nematic films are investigated; the latter aligned in homeotropic or planar geometries. Their room-temperature adhesion, determined through a 90-degree peel test, is consistent with theoretical predictions and strongest in a planar geometry (peeled parallel to the director) with adhesive force per unit length of 0.67 Nmm-1. In contrast, adhesion of the planar perpendicular, isotropic and homeotropic films is 62.5%, 38.5% and 23.0% lower, respectively. The surface contribution to adhesion is identical for all films, confirming that the variation in adhesion is determined solely by the bulk LCE alignment controlled during film preparation. A temperature-dependent adhesion factor is determined from 0 Celsius to 80 Celsius using dynamic mechanical analysis, and found to be in excellent agreement with the peel data at room temperature. Molecular relaxations active above the glass transition temperature are dominant in determining LCE adhesion. The results show that side-chain LCEs can function as transparent, tunable, broad-temperature smart PSAs
format Preprint
id arxiv_https___arxiv_org_abs_2507_07639
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Geometry-Dependent Adhesion in Transparent, Monodomain Liquid Crystal Elastomers
Street, Aidan
Mistry, Devesh
Mattsson, Johan
Gleeson, Helen F.
Soft Condensed Matter
Materials Science
74C10
Elastomeric pressure-sensitive adhesives (PSAs) form adhesive bonds under light pressure. Liquid crystal elastomers (LCEs) are exciting PSA candidates as they can impart both anisotropy and temperature-dependence to adhesion, but the full potential of their anisotropic adhesion is unexplored. Here, identical side-chain LCEs, produced as transparent isotropic or nematic films are investigated; the latter aligned in homeotropic or planar geometries. Their room-temperature adhesion, determined through a 90-degree peel test, is consistent with theoretical predictions and strongest in a planar geometry (peeled parallel to the director) with adhesive force per unit length of 0.67 Nmm-1. In contrast, adhesion of the planar perpendicular, isotropic and homeotropic films is 62.5%, 38.5% and 23.0% lower, respectively. The surface contribution to adhesion is identical for all films, confirming that the variation in adhesion is determined solely by the bulk LCE alignment controlled during film preparation. A temperature-dependent adhesion factor is determined from 0 Celsius to 80 Celsius using dynamic mechanical analysis, and found to be in excellent agreement with the peel data at room temperature. Molecular relaxations active above the glass transition temperature are dominant in determining LCE adhesion. The results show that side-chain LCEs can function as transparent, tunable, broad-temperature smart PSAs
title Geometry-Dependent Adhesion in Transparent, Monodomain Liquid Crystal Elastomers
topic Soft Condensed Matter
Materials Science
74C10
url https://arxiv.org/abs/2507.07639