Self-healing Functional Polymers: Optical Property Recovery of Conjugated Polymer Films by Uncatalyzed Imine Metathesis

Abstract

The implementation of a self-healing functionality into materials has become a prevalent approach for materials which require long-term reliability. As of today, the restoration of mechanical properties has dominated the research on selfhealing materials, whereas research on healing of other functionalities (e.g., conductivity or optical properties) is still in its infancy. Here, the first conjugated polymer, which can restore its optical properties after photodamage is reported. The proposed self-healing mechanism relies on a thermally triggered imine metathesis between the conjugated polymer and additional macromolecular healing agents with no catalyst needed.

How to Design a Self‐Healing Polymer: General Concepts of Dynamic Covalent Bonds and Their Application for Intrinsic Healable Materials

“…Furthermore, polymers are often used for coatings, encapsulations or materials with specific optical properties . Transparent materials can get opaque upon damage and lose their applicability for, e.g., solar cells.…”

“…Lei et al demonstrated one way to realize these properties, using a combined imide–imine system which, in addition, is recyclable and self‐healing . Recycling and malleability as well as an improved mechanical strength can also be achieved by carbon fiber composites, as it has been shown by Taynton et al The implementation of imine bonds into conjugated copolymers can be beneficial in order to design highly functional polymers, which can recover their optical properties by healing via the imine metathesis mechanism …”

Recoverable and self-healing electromagnetic wave absorbing nanocomposites

“…[23] Self-healing can be obtained by generating reversible chemical covalent bonds in the materials network, [24][25][26][27] those chemical interactions include acylhydrazone bonds, [28][29][30] disulfide bonds, [31,32] boronic ester linkages, [33] diarylbibenzofuranone links, [34] thiuram disulfide units, [35] Diels-Alder reactions, [36] and imine bonds (-CH=N-). [37][38][39][40] Notably, Bao and co-workers synthesised a polydimethylsiloxane (PDMS) elastomer with spontaneous self-healing function by forming supramolecular dynamic interactions with coordination complexes. [41] In this work, we propose a synthesis strategy to achieve EM wave absorbing nanocomposites by using dynamic imine bonds-based polyazomethine (PAM) as macromolecular interconnects and Fe3O4-loaded multiwalled carbon nanotubes (Fe3O4@MWCNTs) as EM wave absorbing units.…”

Autonomous Supramolecular Interface Self‐Healing Monitored by Restoration of UV/Vis Absorption Spectra of Self‐Assembled Thiazole Layers

“…Impressive progress has been achieved in self-healing mechanical properties of polymers, as for example, reviewed by Yang et al [1] and Ahnere tal. [2] Recently,a lso self-healing concepts to restoree lectronic [3] or optical [4] properties of polymeric bulk materials have been introduced that enablee xtending the lifetime of organic optoelectronic devices. However, the lattere ssentially dependso nt he integrity of the carefully designedi nterfaces between the functional materials, [5] which need to self-heal as well to achieve prolongedl ifetimes of any optoelectronica nd electronic device.…”