Intrinsically Luminescent, Reprogrammable, and Chemically Recyclable Liquid Crystal Elastomers Enabled by Dynamic...

Area of Science:

• Materials Science
• Polymer Chemistry
• Soft Robotics

Background:

• Liquid crystal elastomers (LCEs) are crucial for soft actuators but lack integrated reprogrammability, recyclability, and luminescence.
• Existing exchangeable LCE systems face challenges in achieving these multiple functionalities simultaneously.

Purpose of the Study:

• To develop a novel LCE material that integrates reprogrammability, chemical recyclability, and intrinsic luminescence.
• To utilize dynamic vinylogous urethane (VU) bonds as both crosslinking points and luminescent centers.

Main Methods:

• Synthesis of a polydomain vinylogous urethane-based LCE (VULCE) utilizing dynamic VU bonds.
• Characterization of mechanical properties (Young's modulus, toughness).
• Demonstration of catalyst-free transamination for reprogramming into 3D actuators.
• Depolymerization and repolymerization for chemical recycling.
• Investigation of intrinsic luminescence via clustering-triggered emission (CTE).

Main Results:

• The VULCE material exhibits excellent mechanical properties (Young's modulus: 1.45 ± 0.08 MPa, toughness: 148.26 ± 0.11 KJ m⁻³).
• Reprogrammable 3D actuators were achieved with reversible actuation at 110°C.
• Successful chemical recycling via depolymerization and repolymerization into new VULCE materials.
• Intrinsic blue fluorescence was observed due to the CTE effect.

Conclusions:

• A novel VULCE material with integrated reprogrammability, recyclability, and luminescence has been successfully developed.
• The dynamic VU bonds enable versatile applications in advanced soft actuators and functional materials.
• This work provides new avenues for designing multifunctional LCEs.