最新刊期
卷 27 ， 期 8 ， 2014
- 摘要：Bottlebrushes are densely grafted polymers, with properties distinctly different from those of sparsely grafted or linear polymers. Bulky side chains are packed around the backbone, and the steric effect between neighboring side chains forces the backbone to adopt a stretched conformation. Besides, compared with normal linear polymers,molecular weights of bottlebrushes can reach 106g/mol easily. And bottlebrushes can form nanometer structures of tens to hundreds of nanometers with a wide range of applications. Currently, researches working on bottlebrushes are mainly focused on synthesizing bottlebrushes of well-defined chemical structures, their physical structures, properties, and applications based on bottlebrushes with coil main chains and coil side chains. Here,this review covers the synthetic approaches towards bottlebrushes with well-defined structures, recent advances in bottlebrushes with rod side chains or rod backbones, and properties and applications of bottlebrushes.关键词：Bottlebrushes;Graft copolymers;Rigid backbone;Rigid side chians
- 5
- |
- 15
- |
- 3
发布时间：2022-09-18 - 摘要：Sequence-regulated polymerization is the Holy Grail of polymer science,which paves the way towards hierarchical structures and sophisticated functions. The ultimate goals of sequence-regulated polymerization are to develop new polymerization methods to precisely control the polymer chain microstructures, to get insight on the polymer structure ind property relationship; to deeply understand the intramolecular interaction of a single polymer chain as well as polymer chain interactions, and finally to realize the controlled single polymer chain folding and precise self-assembly of several )olymer chains as well as develop new functional polymeric materials. Recent progress of in biomacromolecule synthesis, templated polymerization, solid-phase synthesis, chain-growth polymerization as well as step-growth polymerization is highlighted. Moreover, we outlook the future direction of ultra-precise and highly efficient sequence regulation nethodology,and the effect of sequenced microstructures on material properties.关键词：Sequence-regulated polymerization;Precise microstructure of polymer chain;Structure-property relationship
- 4
- |
- 12
- |
- 0
发布时间：2022-09-18 - 摘要：With the development of mechanochemistry and polymer materials, design of novel polymer materials to achieve mechanical response becomes important. One of the key issues of designing mechano-responsive materials is to discover novel mechanophores, which can be mechanochemically mediated to induce chemical transformation. This review will focus on the mechanochemical transformation of mechanophores, such as the break and formation of covalent bonds and the non-covalent interactions. In the case of covalent bonds, we focus on the inducing stimuli,such as sonication,tension and pressure; in the case of non-covalent interactions,different kinds of non-covalent interactions,such as hydrogen bonding and π-π interaction are discussed. With a better understanding of mechanochemical mechanisms and mechanophore design, more novel functional materials can be developed. We believe that research on mechanochemistry will offer a unique opportunity for the development of polymer materials.关键词：Mechanochemistry;Polymer material;Mechanophore
- 3
- |
- 8
- |
- 1
发布时间：2022-09-18 - 摘要：The complexes formed by DNA or RNA interacting with polycations have been widely used as non-viral gene vectors. Owing to the strong and long-ranged electrostatic interaction,the complex is usually controlled by kinetics and its structure evolves with time. This review summarized the recent studies on kinetics of the complexation between DNA/RNA with polycations. We proposed that the major factors determining the kinetics of complexation were the balance between the long-ranged electrostatic repulsion force and the short-ranged electrostatic attraction forces, as well as the intra- and inter- complex disproportionation rate. The disclosure of the complexation mechanism is helpful in developing high performance gene delivery vectors.关键词：DNA/RNA;Complex;Gene delivery;Kinetics
- 2
- |
- 9
- |
- 0
发布时间：2022-09-18 - 摘要：Peptide- and protein-based hydrogels are an important class of biomaterials and have received intense research interest in recent decades. The gelation occurs either through the supramolecular assembly or the controlled reaction between reactive residues. The synergy between physical and chemical crosslinking often leads to dramatic improvement of the performance of these hydrogel materials. The unique biological role of peptides and proteins,their structural diversity and functional plasticity have promised numerous opportunities for biomaterials. This review is a brief introduction to the design principles,a summary of the recent progresses,and a perspective on its future direction.关键词：Biomaterials;Hydrogels;Peptides;Proteins;Polymers
- 2
- |
- 8
- |
- 0
发布时间：2022-09-18 - 摘要：Polyoxometalates have well-defined structures and remarkable properties with great potentials to meet contemporary material demands in the field of catalysis, electrooptical devices, and pharmaceuticals. The polyoxometalate/ polymer supramolecular hybrid materials not only combine unique properties and functionalities of polyoxometalates with favorable stability and processability of polymers,but also have flexible functional regulation. Suprmolecular strategies including electrostatic interaction, hydrogen bonding, and covalent bonding are widely applied to incorporate polyoxometalates into organic polymer matrices. In this article we provide an overview of lastest progress of the fabrication strategies,self-assembling behavior,and functional regulation of these supramolecular hybrid materials.关键词：Polyoxometalate;Organic polymer;Supramolecular assembly;Hybrid materials
- 2
- |
- 9
- |
- 1
发布时间：2022-09-18 - 摘要：In virtue of the excellent mechanical performance, high specific strength and specific modulus, light weight, electrical conductivity and good thermal/chemical stability, carbon fibers (CFs) and carbon fiber reinforced composites have been utilized as high performance structural materials in aircraft, aerospace, construction, transportation, biomedical devices, sporting goods and electrical-related application fields over half a century. During the past two decades, benefiting from the rapid development of nanomaterials, nanotechnology and efficient renewable energy devices, CFs (e. g. commercial carbon fibers,carbon fiber fabrics, carbon nanofibers and carbon nanotube fibers,etc. ) with exceptional mechanical properties have been extensively adopted and investigated as alternative electrode materials in a variety of electrochemical and photoelectrical conversion devices due to their advantages of good conductivity, electrochemical properties, porosity and surface modifications. For the first time, this study reviewed the research development of current CF-based energy devices. With an understanding of the development history and applications of CFs, several fundamental knowledge about the CF surface functionalization and electrode preparation were introduced. Then, this work overviewed the recent progress on CF-based energy devices, with a focus on the research development and applications of carbon fibers as functional electrode materials for fuel cells, microbial fuel cell, lithium ion batteries, electrochemical capacitors and solar cells. Finally, through the summary of the state-of-the-art CF-based energy devices, predictions and insights into the challenges and the future development trends on the material preparations, electrode design, optimization of device performances and device integration technologies were proposed.关键词：Polyacrylonitrile (PAN);Carbon fiber;Energy devices;Photoelectrochemical;Solar cells
- 3
- |
- 9
- |
- 0
发布时间：2022-09-18 - 摘要：Four armed polyethylene glycol (T-PEG) was modified with DOPA and disulfide bonds at the chain end to afford the gelator of PEG-DOPA. PEG-DOPA could form hydrogel rapidly with sodium periodate (NalO4) in the system. It was found that the hydrogel degraded in the presence of glutathione solution (GSH),and the degradation time could be adjusted by using different concentrations of GSH. The mechanical strength was obviously enhanced with DOPA in the structure of gelator,and the mechanical modulus of hydrogels increased with increasing the concentration of PEG-DOPA. BMSCs cells were cultured in the hydrogels that showed no cytotoxicity.关键词：Polyethylene glycol;Dopa;Hydrogel;Biomedical materials;Tissue engineering
- 3
- |
- 9
- |
- 0
发布时间：2022-09-18 - 摘要：In gel permeation chromatographic (GPC) experiments of polymers, the quantitative relationship between elution volume and molecular weight, which is generally given by an empirical calibration equation, is very important. However, a clear theoretical derivation to this equation is absent in present polymer textbooks. This paper derives the two calibration equations widely used in experiments in terms of diffusion separation model and conformational entropy model, and gives the theoretical expressions for the phenomenological coefficients involved in the calibration equations. We further deduce the application range of the equations,which can be confirmed by literatures.关键词：Gel permeation chromatography (GPC);Calibration equation;Diffusion separation theory;Conformational entropy
- 2
- |
- 11
- |
- 0
发布时间：2022-09-18
- Technical support is provided by Beijing Founder electronics co., LTD 京ICP备09064830号-19
京公网安备11010802024621 - It is recommended to read the content of this site in Chrome&IE9+. Please switch to extreme mode in browser 360.
- Cookies We use cookies to help provide and enhance our service and tailor content. By continuing, you agree to the use of cookies.
0