Jinying Yuan

Liquid crystal elastomer (LCE) fibers have shown great potential as shape‐memory soft materials due to their large and reversible deformation capacity. However, fabrication methods for LCE fibers with ultrafast thermal response and the exploration of the factors influencing their thermal actuation performance remain limited. A tandem alignment strategy based on electrospinning is presented to fabricate highly aligned LCE fibers. These LCE fibers achieve an order parameter of up to 0.78 and exhibit exceptional actuation performance under thermal stimulation, including an actuation strain of 80%, an actuation speed of 1485% s ⁻¹ , and a peak power density of 6105 W kg ⁻¹ . Furthermore, the actuation performance can be significantly enhanced by resonance. Under constant heating conditions, modulation of the heating frequency enables the actuation speed of the LCE fibers to be amplified up to 10‐fold, achieving bioinspired energy efficiency optimization similar to the wing‐flapping of insects. The LCE fibers demonstrate promising applicability in scenarios requiring ultrafast and efficient thermal actuation.

RAFT-mediated polymerization-induced self-assembly (PISA) combined with crystallization-driven self-assembly (CDSA) yields monodisperse anisotropic nanoparticles, which undergo morphological evolution into heterostructured nanowires.

Nano materials based on poly(ionic liquid)s (PILs) have been extensively studied in recent decades due to their unique abilities in morphological control and applications in catalysts. The self-assembly of PILs enables the formation of diverse nanostructures (such as spheres or vesicles), typically exhibiting high specific surface areas, which are highly desirable in catalysis. This review first summarizes common synthetic methods for PILs and then focuses on explaining the principles of PIL self-assembly and strategies for morphology control, while also comparing different self-assembly approaches. Furthermore, from a macroscopic perspective, applications of PILs in catalysis are discussed, coupled with particular emphasis on comparing their roles in composite materials, highlighting their irreplaceable function in heterogeneous catalytic systems. Finally, current research challenges and perspectives on future developments of PILs are also presented.

The precise preparation of monodisperse and size-regulable nanoparticles by polymerization-induced self-assembly (PISA) facilitates the fabrication of printable colloidal photonic crystals.

Self‐healing materials can recover the materials from physical damage, and extend the life of equipment. Metal coordination bonds are supramolecular interactions with tunable stability and sensitivity to external stimuli, which are crucial for developing self‐healing materials. Incorporating metal coordination bonds into elastomers and coatings can enable materials to repair damage and enhance material performance. This review details the advance in self‐healing elastomers and coatings. The structural characteristics, mechanical properties, and self‐healing efficacy of these materials are discussed, and a perspective on the challenges and development directions is given.

Polymerization-induced self-assembly (PISA) has emerged as a versatile and powerful methodology for the in situ generation of polymeric nanostructures with diverse morphologies and functionalities. Currently, dynamic covalent bonds (DCBs), known for their reversible and stimulus-responsive nature, offer a sophisticated tool for the precise modulation of polymer assemblies. The incorporation of DCBs into PISA facilitates the disaggregation, morphological transition, surface modification, controlled release, and intra- and inter-micellar crosslinking of assemblies, thereby expanding the applications of PISA assemblies in drug delivery, targeted controlled release, molecular recognition, sensing, and modifiable micelle-crosslinked gels. The combination of PISA with DCBs offers a promising approach for designing adaptive and tunable block copolymer nano-object systems, providing new insights and opportunities in the field of polymer chemistry. This review discusses the integration of dynamic covalent chemistry, including disulfide bonds, boronate ester bonds, imine bonds, and [2 + 2] cycloaddition, within the PISA framework and provides guidelines for future research on the development of dynamically responsive and multifunctional PISA nanomaterials.

Liquid crystalline nanoparticles (LC NPs) are a kind of polymer NPs with LC mesogens, which can form special anisotropic morphologies due to the influence of LC ordering. Owing to the stimuli‐responsiveness of the LC blocks, LC NPs show abundant morphology evolution behaviors in response to external regulation. LC NPs have great application potential in nano‐devices, drug delivery, special fibers and other fields. Polymerization‐induced self‐assembly (PISA) method can synthesize LC NPs at high solid content, reducing the harsh demand for reaction solvent of the LC polymers, being a better choice for large‐scale production. In this review, we introduced recent research progress of PISA‐LC NPs by dividing them into several parts according to the LC mesogen, and discussed the improvement of experimental conditions and the potential application of these polymers.

Many material properties are manifested in the morphological appearance and characterized using microscopic images, such as scanning electron microscopy (SEM). Polymer miscibility is a key physical quantity of polymer materials and is commonly and intuitively judged using SEM images. However, human observation and judgment of the images is time-consuming, labor-intensive, and hard to be quantified. Computer image recognition with machine learning methods can make up for the defects of artificial judging, giving accurate and quantitative judgment. We achieve automatic miscibility recognition utilizing a convolutional neural network and transfer learning methods, and the model obtains up to 94% accuracy. We also put forward a quantitative criterion for polymer miscibility with this model. The proposed method can be widely applied to the quantitative characterization of the microstructure and properties of various materials.

This work presents the effective preparation of monodisperse fluoro-nanoparticles by polymerization-induced self-assembly and the convenient formation of well-defined 2D/3D colloidal lattices via solvent evaporation-induced colloidal self-assembly.