Reviews & Analysis

The recent studies on the development of polymeric core crosslinked particles for drug delivery system are reviewed. The first part of this article describes synthesis of polymeric core crosslinked particles via the formation of nanoemulsion, characterization of the particle structure using small angle scattering techniques, and effect of polymer chain conformation on the particle pharmacokinetics and pharmacodynamics. The second part introduces zwitterionic amino acid polymer (ZAP)-based core crosslinked particles and discusses some advantages of using ZAPs as a pilot macromolecule for cancer-targeting chemotherapy.

While the physical properties of polymer solution have been extensively investigated, less is explored at the vicinity of vitrification due to the experimental difficulty. In this study, we analyzed polymerization-induced vitrification during bulk polymerization of methyl methacrylate. Dielectric spectroscopy captured vitrification caused by the change of polymer concentration at a constant temperature. Our study shows that the polymerization solution becomes heterogeneous at the vicinity of vitrification. In addition, this heterogenization coincides with the reaction acceleration classically known as the Trommsdorff effect.

Two specific concepts have emerged in the field of materials science over the last several decades: nanosheets and supramolecular polymers. Based on this background, supramolecular nanosheets, in which these two concepts are integrated, have recently attracted particular attention. This review focuses on design of two supramolecular nanosheets. One is tubulin protein-based supramolecular nanosheet for applications to GTP-responsive drug delivery system. The other is phospholipid-based supramolecular nanosheets and their applications in blood-administrated drug delivery systems.

In this review, the advantages associated with the molecular design of peptides as multifunctional templates for mineralization are initially described. Subsequently, the mechanisms of CaCO₃ nucleation and selective crystal growth achieved under biomimetic mineralization conditions using the designed peptide templates are discussed. Finally, the functional design of peptide–inorganic hybrid materials based on structural control and the use of a mineralization method that can be applied in the engineering and medical fields is considered from the viewpoint of the molecular properties of the peptides.

Nucleobase modification of acyclic XNA oligomers achieved functionalization for use as a novel fluorescent probe and photoswitching system. A linear probe, composed of serinol nucleic acid (SNA) and 5-perylenylethynyl uracil residues, enabled quantitative detection of target RNA through a visually observable change in fluorescent color and intensity. A photoresponsive SNA with two 8-pyrenylvinyl adenine (^PVA) residues established photocontrol of SNA/RNA duplex formation and dissociation. Using a combination of 8-naphthylvinyl adenine (^NVA) and ^PVA demonstrated orthogonal photocontrol system. Thus, nucleobase modifications further expand the utility of acyclic XNA in bionanotechnology.

We review our recent studies in which the optical functions of monomers and π-conjugated polymers are precisely controlled based on flexible heteroatom-containing complexes. The combination of heteroatoms, such as boron, nitrogen, oxygen, and fluorine, creates slightly bent and asymmetric structures against π-surfaces, which induce bending motion in the excited state, providing solid-state luminescence and stimuli-responsive properties. Furthermore, the structures enable π-conjugation to be extended, and the optical functions are finely tuned by polymerization, which restricts the flexibility along the polymer main chain. Our strategy provides novel insights for the development of π-conjugated polymers showing unprecedented functionalities.

Sustainable and 100% biobased plastics, polyamide 11 (PA11), derived from nonedible plants are mixed with polypropylene (PP) and a reactive compatibilizer in a twin-screw extruder. It is found that PP/PA11 bioalloys exhibited surprisingly good impact strength without losing flexural modulus only when the morphology of the PP/PA11 bioalloys was well controlled at nano-meter level, such as “nano-salami” structure. This leads to overcome a past and traditional issues in biobased plastics, resulting in applying for automobile plastic parts. This technology would contribute to realizing “carbon neutrality”.

We fabricated polymer brushes using a novel concept, which involves block copolymer segregation from the polymer region at the water interface. The resulting polymer brush is called a dynamic polymer brush because block copolymer segregation is a dynamic process that occurs at room temperature and is activated through contact with water. Dynamic polymer brushes undergo self-organization in the processes of self-assembly and self-healing (if destroyed). The concept and physical characteristics of dynamic polymer brushes are discussed in this review.

This focus review summarized current adhesives that are capable of macroscopic adhesion in seawater. The design strategies and performance of these adhesives were reviewed based on their bonding methods. Some future research directions and perspectives for under-seawater adhesives were discussed.

Various in situ measurement techniques have been applied to investigate changes in the three-dimensional structures and the physical properties of polyimides (PIs) generated at high pressures using a custom-built optical cell (up to 4,000 atm) or a diamond anvil cell (up to 80,000 atm). Moreover, the structural changes in the PI chain repeating units and interchain distances induced by the ultrahigh pressures were observed with WAXD, and they were compared with optical absorption, fluorescent and phosphorescent emission spectra, infrared absorption spectra, and refractive indexes observed under the same conditions.

Surface modification of carbon materials with polymers is useful for engineering surface properties and adding functionality to carbon materials. This review article describes processes for coating carbon materials with polybenzimidazoles and their applications.

In comparison to the ubiquity of their chalcogenic thiophene analogs, selenophene-incorporated conjugated polymers are relatively scarce in the organic electronics literature. However, this scarcity belies the tremendous utility of selenophene in high-performance optoelectronic materials. In this focus review, we discuss the key developments in selenophene-based conjugated polymer research from the early polyselenophene investigations, through the detailed study of regioregular poly(3-hexylselenophene), to the state-of-the-art donor-acceptor polymers that have enabled advancements in the performance and functionality of various optoelectronic devices. Finally, we end with our perspective on the future of this field.

This review outlines the research across the areas of polymer chemistry and cryobiology We discuss the solutions to problems in cryobiology from the viewpoint of polymeric materials science and the applications of polymer-based cryobiology for biomedical applications. We explain how the recent advances in polymer research have enabled the development of innovative polymeric cryoprotectants with novel mechanisms and the development of state-of-the-art methods for the intracellular delivery of substances, such as drugs, using a cryobiological technique called the freeze-concentration effect.

Recent advances in polymer informatics are reviewed, focusing on experimental research. Data-driven analyses, predictions, and suggestions are becoming more practical, despite the appropriate treatments of higher-order structures and process information acting as bottlenecks. After summarizing recent developments, future challenges in polymer informatics are discussed.

With recent advancements in the Internet of Things (IoT), indoor organic photovoltaic devices (iOPVs) have attracted increasing attention because of their potential utility as self-sustainable, eco-friendly power sources. This review highlights emerging iOPV technologies based on π-conjugated polymers and oligomeric materials and outlines their fundamental principles and characterization techniques.

Intrinsically stretchable semiconducting polymer materials have been sought for meeting requirements in the development of wearable intelligent electronic devices. In this focus review, our recent progress in main-chain engineering for development of intrinsically stretchable n-type semiconducting materials is described. The topics include four strategies, namely, (i) a conjugation-break spacer approach, (ii) a block copolymer approach, (iii) an all-conjugated statistical terpolymer approach, and (iv) a sequence random copolymer approach, in which specially designed stress-relaxation units or sequences are incorporated along the main chains of naphthalene-diimide-based n-type semiconducting polymers.

Chemical design strategies developed in the last decade for conjugated polymer binders in lithium-ion batteries (LIBs) are reviewed here. The first part of this review discusses the mechanism of operation and role of binders in LIBs, and the importance of conductivity in advanced binder systems. The second part of this review gives an account of various conducting polymer binders developed for cathodes and anodes of LIBs. The review concludes with an emphasis on sustainable synthetic design strategies for next-generation conducting polymer binders for greener electrochemical energy storage systems.

As the performance of organic semiconductors has increased so has their molecular structure. In this focused review, we introduce the concept of synergistic catalysis, which involves the use of two or more catalysts with orthogonal reactivity to enable reactions that are not possible with the use of a single catalyst, to synthesize π-conjugated polymers. Synergistic catalysis allows for controlled polymerizations, room-temperature reactions, and/or polymerizations with greater regioselectivity, opening the door to more time-, labor-, cost-, and energy-saving synthetic methods.

We describe here the new concept of developing stimuli-responsive luminochromic materials based on frustrated element-blocks. We termed “frustrated” element-blocks as those that show a relatively larger degree of structural relaxation in the excited state but are structurally restricted. Enhanced sensitivity toward environmental changes and external stimuli can be observed.