Progress in Polymer Science最新文献

The mechanically hard phase and ionically conductive phase endow suitably designed block copolymer electrolytes (BCPEs) with the “Janus” property, thus providing the opportunity to decouple the trade-off between mechanical strength and ionic conductivity by controlling the phase-separated structures. The conductivity of BCPEs is predominantly determined by the molecular structure of block copolymers and the type and concentration of additives, while the manipulation of phase-separated structures helps strengthen their mechanical support and ion transport. This review article presents an overview of BCPEs and focuses on the “molecular structure-phase structure-property” relationship. Ideally, BCPE membranes should have high-throughput and aligned ion transport channels perpendicular to electrodes. First, given the desired attributes of polymer electrolytes, i.e., high ionic conductivity, high strength, low thickness, and high limiting current density, we summarize the research status and optimization strategies for BCPEs. Second, we present a summary of methods that control the phase behavior of BCPEs based on the phase separation mechanism. Third, BCPEs are classified into dual-ion conductor and single-ion conductor, whose advantages and disadvantages are analyzed. Furthermore, we propose a design rationale for high-performance quasi-solid-state BCPEs. We elaborate polymerization methods for the regulation of molecular and phase structure. These aspects are believed to collectively contribute to BCPE membranes with both high ion-conductivity and high mechanical strength, further boosting the development of safe and high-energy solid-state lithium metal batteries.

This review presents the state of the art of complex macromolecular architectures based on polylactide stereocomplexes (PLA-sc) from the viewpoint of synthesis and crystallization. First, we discuss the nomenclature, synthesis, epimerization, and lactide (LA) properties as a bio-derived cyclic dimeric monomer comprising two chiral carbons. Among several polymerization methods, catalytic ring-opening polymerization (ROP) is the most common and versatile technique to access stereoregular (isotactic) PLA, which is the prerequisite to preparing PLA-sc. Combined with other living and controlled/living polymerization techniques, ROP of LA has yielded various PLA-sc-based macromolecular architectures, including copolymers, stars, graft, cyclic, brush, and hybrid materials. New approaches to synthesizing monodisperse discrete oligoLA are also discussed. We show that a small change in the architectures, microstructures, molecular weight, or other chemical and physical modifications affects the behavior of PLA-sc. Moreover, the crystallization of PLA-sc, after more than 30 years of study, still presents many challenges. The crystalline morphology is also a subject of debate. Recent findings suggest a new crystalline unit cell for PLA-sc. Adding a third component or changing chain architecture can significantly modify the properties of the formed PLA-sc. The complex relationship between flexibility, nucleation, diffusion, and the interactions needed for the joint crystallization of the enantiomers constitutes a very large source of variables. As a result, PLA-based stereocomplex materials can be tailored by manipulating one or several of these variables.

ο-Nitrobenzyl (ONB) derivatives are one of the most investigated photo-responsive functional group that features irreversible photolysis under a light stimulus. They are easy to synthesize and display excellent photoactivity, thus have been widely used to construct photo-responsive polymers for numerous applications, such as controlled drug delivery, photodegradable materials, photoinduced micropatterns, etc. This review article is focused on ONB derivatives and their developments in polymer science. The article provides an up-to-date information, including photolysis mechanism, structural design, and materials properties, with a special focus on the application development of ONB derivatives in different areas of polymer science. In addition, the challenges and outlook based on our understanding are also provided. We believe this article will be of interest to the readers from both scientific and industrial communities and will help the readers understand the latest developments in the field, thereby enlightening thoughts for the design of photo-responsive polymers.

Polydopamine (PDA) is a fascinating bioinspired material for the construction of diverse functional materials. In particular, the growing trend of PDA hydrogels clearly reveals the global significance and the intense interest of scientific research in this field. The abundant functional groups make PDA serve as the important structural units for covalent or/and non-covalent interactions with polymers, and anchoring of transition metal ions for hydrogels formation. With these benefits, PDA not only endows hydrogels with various functions such as adhesion, photothermal effect, ultraviolet protection, antioxidant ability, antibacterial properties, but also has been rapidly incorporated into a wide range of applications across the biomedical, environment, energy, and electronic fields. This review strives to provide a comprehensive overview of the relevant advances in the field of bioinspired PDA hydrogels. We start to introduce the PDA as the structural units in hydrogels and dedicate a lot of space to discuss their design and PDA functions in the hydrogels. Furthermore, these functions would bring about various interesting applications of the hydrogels. Some key issues in this emerging field have been also exhibited into discussion which will inspire our thinking in functional hydrogels design.

In polymer science, thermoresponsiveness refers to macromolecular systems that display a marked and discontinuous change in their physical properties with temperature. Such smart polymers are the focus of increasing attention as they provide new solutions to many applications (e.g., drug delivery, nanotechnology, tissue engineering and biotechnology). This review focuses on amino acid based polymers, mainly synthetic polypeptides that are obtained by ring-opening polymerization. These include polymers based on natural amino acids, synthetic or modified amino acids and N-alkylated glycine derivatives. Based on what is known about the behavior of natural proteins in response to temperature variations, this review provides a comprehensive overview of the state of the art of thermosensitive polypeptides through a detailed description i) of the structure/thermoresponsiveness relationship, ii) of the mechanisms involved at the molecular level, iii) of their possible applications both in materials science and in biomedical applications.

The introduction of chemical and/or optical nonlinearity to 3D-printing has paved the way towards volumetric 3D-printing, enabling remarkable advancements in speed, resolution, and the fabrication of previously inaccessible materials. Given the growing interest of the scientific community, we present a critical review that aims to provide a comprehensive discussion of the potential of volumetric 3D-printing. First, the theoretical framework of photopolymerization is summarized. Subsequent sections highlight the progression of light-based 3D-printing from traditional to emerging volumetric 3D-printing techniques, encompassing both single- and multi-photon polymerization. Special attention is given to the rapidly advancing subfield of volumetric bioprinting which holds great promise for the fabrication of complex multi-material tissue constructs. Finally, critical considerations and limitations of volumetric 3D-printing as well as prospective solutions and opportunities for future research are discussed to allow readers to appreciate and participate in the exciting and rapidly advancing field of volumetric 3D-printing.

A fundamental endeavour in macromolecular science is the control of molecular-level complexity, including molecular weight distribution, end groups and architecture. Since the discovery that native biomacromolecules can have a specific sequence translating in a specific biological function, controlling individual monomer sequence has become the ultimate expression of molecular-level complexity. Replicating this remarkable structural precision in abiological macromolecules has emerged as a defining goal and challenge within polymer science. In this Review, we survey developments in synthetic methods, characterisation techniques, simulation workflows and applications relevant to this goal. We also address the broader question of to what extent is such control of molecular-level complexity significant in macromolecules. Specifically, we will focus on characterisation in this Review because of its importance in connecting synthesis with applications.

Hydrophilic polymers are a major class of polymers in polymer science. They are found in a broad range of applications from superabsorbers to drug-delivery. In recent years, a plethora of impactful developments in hydrophilic polymers have been reported. The present review gives an overview over these developments with a focus on frequently studied polymer types, aqueous multi-phase systems, hydrophilic block copolymer self-assembly and hydrophilic polymer particles. We cover fundamental work and concepts but also present work with high relevance for application. Finally, we give an outlook towards current challenges and future developments of the field. The further development of hydrophilic polymer is of great importance for a broad range of applications and will have a significant impact on biomedicine and every-day life.

Natural macromolecules, such as proteins and nucleic acids, display various complex functionalities in biological systems. These functionalities depend on the macromolecular structure, which is determined by the sequence of monomers as well as stereochemical factors. Over the past decade, synthetic methods have evolved to enable complete control over sequential monomer assembly. The precise control over the primary structure of abiotic macromolecules holds the promise to realize complex functionality, similar to natural biopolymers. One of the key features in biological processes involves chirality. Therefore, stereochemical considerations are a prerequisite for mimicking biological systems using synthetic polymers. Here, the progress made in the field of stereo-controlled, sequence-defined polymers is summarised. The impact of monomer sequence and stereocontrol on the physicochemical properties of polymers and their emerging functions is discussed, which underlines the importance of controlling macromolecular structure with high precision. In addition to describing synthetic methods leading to stereocontrolled and sequence-defined macromolecules, limitations and problems in their fabrication are highlighted. The review also includes examples showing how sequence and stereocontrol affect the thermal properties and degradation of polymers, which are critical in the engineering and application of polymer materials. The secondary and tertiary structures are responsible for the functions of natural polymers; therefore, the ability of abiotic macromolecules to fold and self-assemble is discussed in detail, with an emphasis on systems beyond polyamides related to protein skeletons. Furthermore, examples of functions that have been displayed by abiotic macromolecules of defined sequence and chirality are presented. The review article focuses on discrete macromolecules built based on abiotic backbones, including oligomers. In the concluding section, the collected examples are used to elucidate how monomer arrangement and stereocontrol can bring abiotic polymers to a high level of functionality, as manifested by natural macromolecules.

Block polymers comprising covalently joined polymeric segments represent a class of nanostructured, multicomponent polymeric materials. Polymerization-induced microphase separation (PIMS) is an intriguing subset that allows for simultaneous nanostructuring during block polymer synthesis. In contrast to polymerization-induced self-assembly (PISA), useful for the spontaneous formation of block polymer micelles, PIMS is well suited to fabricating monolithic block polymer materials by turning a whole polymerization mixture into a nanostructured solid. With the in situ cross-linking feature, PIMS offers a facile route to nanostructured block polymer thermosets in combination with various polymerization techniques, from emulsion polymerization to 3D printing. This review aims to provide a comprehensive overview and practical guide on PIMS by covering its historical background and mechanistic aspects and also highlighting representative material classes and applicable polymerization techniques.