Molecular Engineering of Photodeformable Liquid Crystal Polymers: Chemical Structure and Network Topology

In
recent years, photodeformable liquid crystal polymers (LCPs)
have attracted considerable interest as a promising class of materials
for soft actuators. The continuous enhancement of performance and
functionality in photodeformable LCPs highly depend on their chemical/physical
cross-linking, the alignment of mesogens and chemical architectures
in the polymer network. As a result, a range of techniques for LC
alignment, cross-linking, and actuator fabrication have been developed,
each tailored to specific chemical processes and offering different
programming capabilities. This review examines the evolution of polymeric
networks, progressing from permanently cross-linked networks through
covalent adaptable networks to physically cross-linked linear LCP
systems, offering insights into the interplay among chemical composition,
alignment approaches, and processing methods. Finally, we outline
unresolved challenges and promising avenues that are poised to drive
the field forward.