Tuning Mechanical and Self-Healing Properties Using Multivalent Crosslinking

TL;DR

This paper shows how using crosslinkers with multiple bonding points can improve the strength and self-healing abilities of polymer materials.

Contribution

The study introduces the use of multivalent crosslinkers to systematically tune mechanical and self-healing properties in polymers.

Findings

Multivalent crosslinkers enhance mechanical properties of polymer networks.

Self-healing performance can be improved by increasing crosslinker valency.

Thiol-Michael chemistry enables tunable, thermoresponsive polymer networks.

Abstract

Dynamic crosslinking in polymer networks has played a
major role
in contributing to various material properties, including toughness,
tensile resistance, and self-healing. Dynamic covalent crosslinking,
which connects two points on the polymer backbone using divalent crosslinkers,
has been studied to date. Here, we systematically investigate the
impact of using multivalent crosslinkers on the mechanical and self-healing
properties of polymer materials. We used the thiol-Michael “click”
chemistry to crosslink thiol–maleimide functional groups, which
are well known for their thermoresponsive dynamic properties. Di-,
tri-, tetra-, and hexathiols were used as crosslinkers to increase
the complexity of the crosslinked polymer network. The results indicated
that the mechanical and self-healing properties can be tuned by using
multivalent networks, potentially paving the way for the development
of better self-healing elastomers and opening opportunities for new
chemistries to be explored.

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