Self‐assembly of side‐chain liquid crystalline block copolymers to anisotropic polymeric nanoparticles

Abstract

Anisotropic polymeric nanoparticles (NPs) have attracted considerable attention due to their morphology-dependent applications in the fields of nanocatalysts, drug delivery and sensors. By introducing liquid crystalline (LC) driving force into NPs, the region of non-spherical shapes in phase diagrams can be broadened effectively, which attracts great interest of many researchers. LC mesogens can be easily introduced to monomers, such as acrylates and methacrylates, as side groups connected by spacers with tunable length, and then side-chain LC polymers can be acquired after polymerization accordingly. Among these polymers, amphiphilic block copolymers (BCPs) have been widely studied, attributed to their property of spontaneous assembly into NPs under appropriate conditions. In this review, based on traditional solution self-assembly and polymerization-induced self-assembly, the recent research into side-chain LC BCP NPs is elaborated in terms of the aspects of the types of LC mesogens, LC phases, morphologies and functionalities. Finally, we summarize recent progress, and prospect the development trend in the future.

Recent progress in polymerization‐induced self‐assembly: From the perspective of driving forces

“…[ 192 ] The competition between the hydrophobic interactions and the liquid crystalline ordering leads to polymer assemblies with a rich variety of morphologies, such as ellipsoidal micelles, ellipsoidal vesicles, cuboids, and lamellae (Figure 10). [ 111,112,123–126,193–197 ]…”

“…Besides the hydrophobic interactions, other supramolecular interactions, including hydrogen bonding, [ 93–96 ] electrostatic interactions, [ 97–104 ] and π‐π interactions, [ 105–107 ] have also been exploited as the driving force for PISA (Figure 1B). Besides, some systems that involve multiple supramolecular driving forces, such as crystallization, [ 60,62,108–110 ] and liquid crystallization, [ 111 ] have also been used to direct the PISA. Owing to the different self‐assembly mechanisms of these driving forces, polymer assemblies stabilized by these supramolecular interactions have shown distinct structures, dynamicity, responsiveness, and functionality.…”

Special issue: polymer science and engineering of elastomers stretching elastomers to their limits

“…A review highlights the opportunity to introduce liquid crystalline structure into block copolymers with an in-depth assessment of structureproperty-morphology relationships. 1 Elastomers are often combined with fillers to improve performance, and nanoscale silica remains as a popular means to tune elastomeric properties. Recent advances in the design of automobile tires that invoke the principles of green chemistry and engineering illustrates the emerging importance of circularity in the design of next generation polymers.…”