Liver is a vital organ in the human body and plays a central role in the metabolism and detoxification of endotoxins and exotoxins.Bilirubin is an endotoxin derived from hemoglobin(Hb).Removing excess bilirubin in the...Liver is a vital organ in the human body and plays a central role in the metabolism and detoxification of endotoxins and exotoxins.Bilirubin is an endotoxin derived from hemoglobin(Hb).Removing excess bilirubin in the blood is crucial for the treatment of liver diseases.Hemoperfusion,which relies on adsorbents to efficiently adsorb toxins,is a widely applied procedure for the removal of blood toxins.To broaden and improve the range and performance of hemoperfusion adsorbents,we synthesized cationic hyper crosslinked polymers(HCPs)with strong affinity for bilirubin.This material exhibited outstanding adsorption performance,with a maximum adsorption capacity of 934 mg/g and a removal efficiency of 96%.Further investigation confirmed their excellent selectivity,reusability,and biocompatibility.These findings expand the potential applications of HCPs and provide insight into strategies for constructing promising hemoperfusion adsorbent materials.展开更多
D-π hybridization is a key structural feature that may significantly affect the intrinsic electronic properties of metallopolymers.Herein,we present the electrosynthesis and memristive properties of metallopolymers u...D-π hybridization is a key structural feature that may significantly affect the intrinsic electronic properties of metallopolymers.Herein,we present the electrosynthesis and memristive properties of metallopolymers using the distinct d-π hybridization monomers R_(1) and R_(2).R_(1)(Ru^(Ⅱ)-(tpz)Cl_(2))features tetradentate ligands(tpz,6,6'-di(1H-pyrazol-1-yl)-2,2'-bipyridine)enforcing quasi-octahedral geometry;R_(2)(Ru^(Ⅱ)-(bpp)_(2))incorporates tridentate ligands(bpp,2,6-di(1H-pyrazol-1-yl)pyridine)inducing pronounced geometric distortion.The planar ligand(tpz)in R_(1) facilitates ordered molecular assembly through high conformational rigidity and extensive π-π stacking,resulting in increased molecular densities and enhanced morphological uniformity compared to R_(2) metallopolymers.Due to pyrazole’s weaker π-acceptance and strongerσ-donation compared to pyridine,R_(1) exhibits a 119 nm red-shift in metal-to-ligand charge transfer(MLCT)band and a 30 mV anodic shift in Ru^(+2/+3)redox potential relative to R_(2).Coupled with a reduced HOMO-LUMO gap,the uniform and ordered structure leads to a lower conductance decay constant in R_(1).Additionally,R_(2) metallopolymers exhibit superior memristive performance(characterized by lower switching voltage and higher switching ratio)via redox-induced aromatic transitions in axial ligands enhancing electronic delocalization.This work compares two metallopolymers with different ligand geometries,revealing how this difference leads to distinct charge transport and memristive behaviors.展开更多
Among various architectures of polymers,end-group-free rings have attracted growing interests due to their distinct physicochemical performances over the linear counterparts which are exemplified by reduced hydrodynam...Among various architectures of polymers,end-group-free rings have attracted growing interests due to their distinct physicochemical performances over the linear counterparts which are exemplified by reduced hydrodynamic size and slower degradation.It is key to develop facile methods to large-scale synthesis of polymer rings with tunable compositions and microstructures.Recent progresses in large-scale synthesis of polymer rings against single-chain dynamic nanoparticles,and the example applications in synchronous enhancing toughness and strength of polymer nanocomposites are summarized.Once there is the breakthrough in rational design and effective large-scale synthesis of polymer rings and their functional derivatives,a family of cyclic functional hybrids would be available,thus providing a new paradigm in developing polymer science and engineering.展开更多
Tactile perception plays a vital role for the human body and is also highly desired for smart prosthesis and advanced robots.Compared to active sensing devices,passive piezoelectric and triboelectric tactile sensors c...Tactile perception plays a vital role for the human body and is also highly desired for smart prosthesis and advanced robots.Compared to active sensing devices,passive piezoelectric and triboelectric tactile sensors consume less power,but lack the capability to resolve static stimuli.Here,we address this issue by utilizing the unique polarization chemistry of conjugated polymers for the first time and propose a new type of bioinspired,passive,and bio-friendly tactile sensors for resolving both static and dynamic stimuli.Specifically,to emulate the polarization process of natural sensory cells,conjugated polymers(including poly(3,4-ethylenedioxythiophen e):poly(styrenesulfonate),polyaniline,or polypyrrole)are controllably polarized into two opposite states to create artificial potential differences.The controllable and reversible polarization process of the conjugated polymers is fully in situ characterized.Then,a micro-structured ionic electrolyte is employed to imitate the natural ion channels and to encode external touch stimulations into the variation in potential difference outputs.Compared with the currently existing tactile sensing devices,the developed tactile sensors feature distinct characteristics including fully organic composition,high sensitivity(up to 773 mV N^(−1)),ultralow power consumption(nW),as well as superior bio-friendliness.As demonstrations,both single point tactile perception(surface texture perception and material property perception)and two-dimensional tactile recognitions(shape or profile perception)with high accuracy are successfully realized using self-defined machine learning algorithms.This tactile sensing concept innovation based on the polarization chemistry of conjugated polymers opens up a new path to create robotic tactile sensors and prosthetic electronic skins.展开更多
Organisms are capable of self-growth through the integration of the nutrients provided by the external environment.This process slows down when they grow.In this study,we mimicked this self-regulated growth via a simp...Organisms are capable of self-growth through the integration of the nutrients provided by the external environment.This process slows down when they grow.In this study,we mimicked this self-regulated growth via a simple swelling-polymerization strategy in which the stretching polymer chains in the original networks provide entropic elasticity to restrict growth in high growth cycles.Using typical covalently crosslinked polymers,such as acrylamide-based hydrogels and HBA-based elastomers,as examples,we demonstrate that the crosslinked polymers can absorb polymerizable compounds through a swelling-polymerization process to expand their sizes,but the growth extent becomes smaller with increasing growth cycle until reaching a plateau.In addition to their size,these materials become stiffer and exhibit less swelling ability in solvents.Our work not only provides a new growing mode to tune the properties of crosslinked polymers but also discloses the underlying mechanism of crosslinked polymers in multi-cyclic swelling conditions.展开更多
Cholesteric liquid crystals(CLCs)exhibit unique helical superstructures that selectively reflect circularly polarized light,enabling them to dynamically respond to environmental changes with tunable structural colors....Cholesteric liquid crystals(CLCs)exhibit unique helical superstructures that selectively reflect circularly polarized light,enabling them to dynamically respond to environmental changes with tunable structural colors.This dynamic color-changing capability is crucial for applications that require adaptable optical properties,positioning CLCs as key materials in advanced photonic technologies.This review focuses on the mechanisms of dynamic color tuning in CLCs across various forms,including small molecules,cholesteric liquid crystal elastomers(CLCEs),and cholesteric liquid crystal networks(CLCNs),and emphasizes the distinct responsive coloration each structure provides.Key developments in photochromic mechanisms based on azobenzene,dithienylethene,and molecular motor switches,are discussed for their roles in enhancing the stability and tuning range of CLCs.We examine the color-changing behaviors of CLCEs under mechanical stimuli and CLCNs under swelling,highlighting the advantages of each form.Following this,applications of dynamic color-tuning CLCs in information encryption,adaptive camouflage,and smart sensing technologies are explored.The review concludes with an outlook on current challenges and future directions in CLC research,particularly in biomimetic systems and dynamic photonic devices,aiming to broaden their functional applications and impact.展开更多
Internal rotation of conjugated organic backbone seriously impaired room temperature phosphorescence(RTP),leading to rare realization of ultra-long afterglows with RTP lifetimes over 2 s in non-bibulous polymers.Herei...Internal rotation of conjugated organic backbone seriously impaired room temperature phosphorescence(RTP),leading to rare realization of ultra-long afterglows with RTP lifetimes over 2 s in non-bibulous polymers.Herein,N-(bromophenyl)carbazoles are cyclized to lock up phenyl-carbazol internal rotation in advance and the fused nitrogen hetero-cyclic compounds are doped into poly(methyl methacrylate)(PMMA).The results show that locking up the molecular internal rotation can achieve ultra-long RTP polymers with lifetimes over 2 s,in contrast,the unlocked molecules hardly emit RTP in PMMA.The high-lying triplet excitons can transfer the energy to low-lying organic fluorescent dyes,and the persistent multicolor afterglows including white emission can be readily modulated.This work discloses an effective and extendable dopant molecular strategy for developing high-performance ultra-long organic RTP polymers.展开更多
The facile synthesis of high-valued polymers from waste molecules or low-cost common chemicals presents a significant challenge.Here,we develop a series of degradable poly(thiocarbonate)s from the new step-growth poly...The facile synthesis of high-valued polymers from waste molecules or low-cost common chemicals presents a significant challenge.Here,we develop a series of degradable poly(thiocarbonate)s from the new step-growth polymerization of diols,carbonyl sulfide(CoS,or carbon disulfide,CS_(2)),and dichlorides.Diols and dichlorides are common chemicals,and CoS(CS_(2))is released as industrial waste.In addition to abun-dant feedstocks,the method is efficient and performed under mild conditions,using common organic bases as catalysts,and affording unprece-dented polymers.When cos,diols,and dihalides were used as monomers,optimized conditions could completely suppress the oxygen-sulfur exchange reaction,enabling the efficient synthesis of well-defined poly(monothiocarbonate)s with melting points ranging from 48°C to 101°C.These polymers,which have a structure similar to polyethylene with low-density in-chain polar groups,exhibit remarkable toughness and ductili-ty that rival those of high-density polyethylene(melting point:90°C,tensile strength:21.6±0.7 MPa,and elongation at break:576%).Moreover,the obtained poly(monothiocarbonate)s can be chemically degraded by alcoholysis to yield small-molecule diols and dithiols.When CS_(2)was used in place of cos,a pronounced oxygen-sulfur exchange reaction occurred.By optimizing reaction condition,it was found that polymers with-S(C=O)S-and-S(C=S)S-as the main repeating units exhibited high thermal stability and crystallinity.Thus,a new approach for regulat-ing the structure of polythiocarbonates via the oxygen-sulfur exchange reaction is developed.Overall,the polymers hold great potential for green materials due to their facile synthesis,readily available feedstocks,excellent performance,and chemical degradability.展开更多
Low dielectric constant(low-k)materials are critical for advanced packaging in high-density microelectronic devices and high-frequency communication technologies.Ladder polysiloxanes,which are characterized by their u...Low dielectric constant(low-k)materials are critical for advanced packaging in high-density microelectronic devices and high-frequency communication technologies.Ladder polysiloxanes,which are characterized by their unique double-chain structure and intrinsic microporosity,offer remarkable advantages in terms of thermal stability,oxidation resistance,and dielectric performance.However,structural defects in ladder polysiloxanes,such as cage-like and irregular oligomers,and their effects on dielectric properties remain underexplored.In this study,a series of ladder-like polysiloxanes(X-TMS)with diverse side groups weresynthesized via a one-step base-catalyzed method.The influence of the benzocyclobutene(BCB)side groups on the formation of regular ladder structures was systematically investigated.Notably,BCB incorporation disrupted the structural regularity,favoring the formation of cage-like and irregular topologies,which were extensively characterized using 29silicon nuclear magnetic resonance spectroscopy(^(29)Si-NMR),Fourier transform infrared spectroscopy(FTIR),gel permeation chromatography(GPC),and X-ray diffraction(XRD).These structural defects were beneficial for improving the hydrophobicity and thermal stability.Copolymerization of X-TMS with commercial DVS-BCB resins further enhanced the mechanical properties,with the elastic modulus increasing from 3.6 GPa to 4.4 GPa and water absorption reduced from 0.33 wt%to 0.06 wt%.This study establishes a clear correlation between topological structures and material properties.These findings not only advance the understanding of the structure-property relationships in ladder polysiloxanes but also provide a novel approach for designing high-performance interlayer dielectric materials for next-generation microelectronics.展开更多
Given the increasing demand for distributed electricity,there is a burning desire to harvest electricity from renewable sources using environmentally friendly methods.Thermoelectric (TE) materials can meet this requir...Given the increasing demand for distributed electricity,there is a burning desire to harvest electricity from renewable sources using environmentally friendly methods.Thermoelectric (TE) materials can meet this requirement not only because of their ability to convert heat directly into electricity,enabling energy harvesting from waste heat and natural heat resources,but also because more than 60%of the energy is lost as waste heat [1].The discovery of the TE effect dates back to the 1820s when T.M.Seebeck observed electricity generation at the junction of two conductors with different temperatures.Additionally,when a voltage is applied to TE materials,they can create a temperature difference to enable solid-state cooling (known as the Peltier effect).Therefore,the TE effect promises both sustainable energy solutions and temperature control technologies.Over the past two decades,the urgent demand for powering ubiquitous Internet of Things devices has sparked significant interest in flexible thermoelectrics(F-TEs),which raises an intriguing question:Is the intrinsically flexible polymer an important candidate for state-of-the-art F-TEs applications?展开更多
Ring polymers are ubiquitous in various fields including biomaterials,drug release and gene therapy.All of these applications involve the dynamics and diffusion process of ring polymers in a confined environment.By us...Ring polymers are ubiquitous in various fields including biomaterials,drug release and gene therapy.All of these applications involve the dynamics and diffusion process of ring polymers in a confined environment.By using dynamic light scattering(DLS),we discovered a dynamical transition for charged ring polymers with increasing ring concentration in the gel matrix from a diffusive state to a non-diffusive topological frustrated state with a more compact conformation.When the ring polymer size is smaller than the mesh size of the gel matrix,the rings are diffusive at low concentration of 5 g/L.The ring diffusion coefficient in the gel matrix is an order of magnitude smaller than that of rings in solution,obeying the Ogston's model.At high ring concentration of 40 g/L,the collective dynamical behavior of the charged rings exhibits a topologically frustrated non-diffusive state,which may originate from the inter-ring threading with the external confinement from the gel matrix.Based on our previous theoretical work,we also conjectured that in such a non-diffusive state,the ring polymers might adopt a more compact conformation with the overall size exponentν=1/3.展开更多
Polymers that exhibit both biodegradability and chemical recyclability offer a promising solution to environmental pollution and resource scarcity. Poly(glycolic acid)(PGA) is a promising chemically recyclable polymer...Polymers that exhibit both biodegradability and chemical recyclability offer a promising solution to environmental pollution and resource scarcity. Poly(glycolic acid)(PGA) is a promising chemically recyclable polymer, characterized by its seawater degradability and high mechanical strength. In this study, aliphatic polycarbonates were synthesized through melt polycondensation and subsequently copolymerized with glycolide(GL) to produce chemically recyclable PGA based triblock copolymers with well-defined structures. The properties of these copolymers, including their thermal properties, crystallization behavior, and mechanical performance, can be effectively adjusted by modifying the structure and content of the middle block. Furthermore, an in-depth investigation reveals that the pyrolysis process involves ester exchange, radical, and back-biting reactions. In addition, the high-efficiency "Monomer↔Copolymer" chemical recycling loop has been established, achieving a remarkable yield exceeding 88% along with a purity greater than 99%.展开更多
Chain-growth radical polymerization of vinyl monomers is essential for producing a wide range of materials with properties tailored to specific applications.However,the inherent resistance of the polymer's C―C ba...Chain-growth radical polymerization of vinyl monomers is essential for producing a wide range of materials with properties tailored to specific applications.However,the inherent resistance of the polymer's C―C backbone to degradation raises significant concerns regarding long-term environmental persistence,which also limits their potential in biomedical applications.To address these challenges,researchers have developed strategies to either degrade preexisting vinyl polymers or incorporate cleavable units into the backbone to modify them with enhanced degradability.This review explores the various approaches aimed at achieving backbone degradability in chain-growth radical polymerization of vinyl monomers,while also highlighting future research directions for the development of application-driven degradable vinyl polymers.展开更多
Understanding the conformational characteristics of polymers is key to elucidating their physical properties.Cyclic polymers,defined by their closed-loop structures,inherently differ from linear polymers possessing di...Understanding the conformational characteristics of polymers is key to elucidating their physical properties.Cyclic polymers,defined by their closed-loop structures,inherently differ from linear polymers possessing distinct chain ends.Despite these structural differences,both types of polymers exhibit locally random-walk-like conformations,making it challenging to detect subtle spatial variations using conventional methods.In this study,we address this challenge by integrating molecular dynamics simulations with point cloud neural networks to analyze the spatial conformations of cyclic and linear polymers.By utilizing the Dynamic Graph CNN(DGCNN)model,we classify polymer conformations based on the 3D coordinates of monomers,capturing local and global topological differences without considering chain connectivity sequentiality.Our findings reveal that the optimal local structural feature unit size scales linearly with molecular weight,aligning with theoretical predictions.Additionally,interpretability techniques such as Grad-CAM and SHAP identify significant conformational differences:cyclic polymers tend to form prolate ellipsoid shapes with pronounced elongation along the major axis,while linear polymers show elongated ends with more spherical centers.These findings reveal subtle yet critical differences in local conformations between cyclic and linear polymers that were previously difficult to discern,providing deeper insights into polymer structure-property relationships and offering guidance for future polymer science advancements.展开更多
As a powerful synthetic tool,ruthenium-catalyzed ring-opening metathesis polymerization(ROMP)has been widely utilized to prepare diverse heteroatom-containing polymers.In this contribution,we report the synthesis of t...As a powerful synthetic tool,ruthenium-catalyzed ring-opening metathesis polymerization(ROMP)has been widely utilized to prepare diverse heteroatom-containing polymers.In this contribution,we report the synthesis of the novel imine-based polymer through the copolymerization of cyclooctene with cyclic imine comonomer via ROMP.Because of the efficient hydrolysis reactions of the imine group,the generated copolymer can be easily degraded under mild condition.Moreover,the generated degradable product was the telechelic polymer bearing amine group,which was highly challenged for its direct synthesis.And this telechelic polymer could also be used for the further synthesis of new polymer through post-transformation.The introduction of imine unit in this work provides a new example of the degradable polymer synthesis.展开更多
This study reviews light-responsive polymers in various applications,including drug delivery,information storage,sensor,self-healing material,antibacterial or anti-fouling,and environmental applications.Light-responsi...This study reviews light-responsive polymers in various applications,including drug delivery,information storage,sensor,self-healing material,antibacterial or anti-fouling,and environmental applications.Light-responsive polymers are a new material type being developed for various medical,electronics,engineering,and environmental applications.The working principle of light-responsive materials is based on metalligand interactions or non-covalent interactions between polymer functional groups,metal ions,and other filler functional groups.Light irradiation causes physical and mechanical changes in drug delivery and antibacterial systems,which results in the materials releasing more drugs or antibacterial substances.When materials in information storage devices and sensors are exposed to light,they can change color or glow.This has been applied for data storage to reveal QR codes under UV light.Additionally,this review discusses the thermodynamic aspects and computer modeling of light-responsive materials to emphasize the importance and development of these materials.Finally,light-responsive polymer development for various applications is presented.展开更多
The crystallization behavior of polymers is significantly influenced by molecular chain length and the dispersion of varying chain lengths.The complexity of studying crystallization arises from the dispersity of polym...The crystallization behavior of polymers is significantly influenced by molecular chain length and the dispersion of varying chain lengths.The complexity of studying crystallization arises from the dispersity of polymer materials and the typically slow cooling rates.Recent advancements in fast cooling techniques have rendered the investigation of polymer crystallization at varying cooling rates an attractive area of research;however,a systematic quantitative framework for this process is still lacking.We employ a coarse-grained model for polyvinyl alcohol(CGPVA)in molecular dynamics simulations to study the crystallization of linear polymers with varying chain lengths under variable cooling rates.Monodisperse,bidisperse and polydisperse samples are simulated.We propose two formulae based on a two-phase assumption to fit the exothermal curves obtained during cooling.Based on these formulae,better estimations of crystallization temperatures are obtained and the effects of chain lengths and cooling rates are studied.It is found that the crystallization temperature increases with chain length,similar to the Gibbs-Thomson relation formelting temperature,indicating a strong relation between fast crystallization and glass formation in linear polymers.Extrapolation to the infinitely slow cooling rate provides an easy way in simulations to estimate the equilibrium crystallization temperature.The effective chain lengths of polydisperse and bidisperse samples are found to be the number-averaged chain lengths compared to the weight-averaged ones.The chain length-dependent crystallization exhibits crossover behavior near the entanglement length,indicating the effects of entanglements under fast cooling conditions.The effect of chain length dispersity on crystallization becomes more obvious under fast cooling conditions.展开更多
Open-shell oligomers and polymers have exhibited intriguing electronic and magnetic properties, making them highly desirable for a wide range of applications, including ambipolar organic field-effect transistors (OFET...Open-shell oligomers and polymers have exhibited intriguing electronic and magnetic properties, making them highly desirable for a wide range of applications, including ambipolar organic field-effect transistors (OFETs), photodetectors, organic thermoelectrics, and spintronics. Although open-shell ground states have been observed in certain small molecules and doped organic semiconductors, the exploration of open-shell ground-state conjugated polymers is still limited, and the strategies for designing these polymers remain obscure. This review aims to briefly introduce the theory and characterization methods of open-shell conjugated polymers, along with an overview of recent progress and applications. The objective is to stimulate further advancements and investigations in this promising area by shedding light on the potential of open-shell conjugated polymers and the challenges that lie ahead.展开更多
The development of n-type polymer thermoelectrics lags far behind that of p-type ones in view of material diversity and performance.New structural insights into the thermoelectric performance are needed for efficient ...The development of n-type polymer thermoelectrics lags far behind that of p-type ones in view of material diversity and performance.New structural insights into the thermoelectric performance are needed for efficient n-type polymer thermoelectric materials.Herein,we developed three acceptor-acceptor type organoboron polymers and investigated the effect of backbone configuration on thermoelectric performance.The three polymers are designed based on double B←N bridged bipyridine(BNBP)unit with monomeric thieno[3,4-c]pyrrole-4,6-dione(TPD),TPD dimer and TPD trimer as the copolymerizing units,respectively.The three polymers show similar low LUMO energy levels but different backbone configuration.Compared with the wavy backbone configuration,the pseudo-straight backbone configuration imparts the polymer with much enhanced crystallinity and electron mobility.As a result,after n-doping,the polymer with pseudo-straight configuration shows much higher electronic conductivity and power factor.We think these findings could serve as important guidelines for molecular design toward efficient n-type polymer thermoelectric materials.展开更多
The coronavirus disease 2019 (COVID-19) pandemic has been at its worst and the world is fighting to help global public health. In this aspect the role played by polymers and polymeric materials including plastics as t...The coronavirus disease 2019 (COVID-19) pandemic has been at its worst and the world is fighting to help global public health. In this aspect the role played by polymers and polymeric materials including plastics as the main material in medical devices, personal protective equipment for health care workers is huge. Advantages like mass production, lower cost and possibilities for sterilization and disinfection of the plastic materials make them an inevitable material in healthcare sector. Apart from plastics, anti-viral and anti-microbial coatings, polymeric nanocomposites and functional polymers have been introduced as a helping tool against COVID-19. This review focuses on the application of polymers, and polymeric materials in COVID-19 pandemic. Usage of plastics and its applications in healthcare and related sectors have been reviewed. The major challenges faced and future prospects on the usage of polymers have also been discussed.展开更多
基金financially supported by the International Cooperation Program of the Ministry of Science and Technology of Hubei Province(No.2023EHA069)Shenzhen Science and Technology Program(No.JCYJ20230807143702005)the National Foreign Experts Program(No.G2022027015L)。
文摘Liver is a vital organ in the human body and plays a central role in the metabolism and detoxification of endotoxins and exotoxins.Bilirubin is an endotoxin derived from hemoglobin(Hb).Removing excess bilirubin in the blood is crucial for the treatment of liver diseases.Hemoperfusion,which relies on adsorbents to efficiently adsorb toxins,is a widely applied procedure for the removal of blood toxins.To broaden and improve the range and performance of hemoperfusion adsorbents,we synthesized cationic hyper crosslinked polymers(HCPs)with strong affinity for bilirubin.This material exhibited outstanding adsorption performance,with a maximum adsorption capacity of 934 mg/g and a removal efficiency of 96%.Further investigation confirmed their excellent selectivity,reusability,and biocompatibility.These findings expand the potential applications of HCPs and provide insight into strategies for constructing promising hemoperfusion adsorbent materials.
文摘D-π hybridization is a key structural feature that may significantly affect the intrinsic electronic properties of metallopolymers.Herein,we present the electrosynthesis and memristive properties of metallopolymers using the distinct d-π hybridization monomers R_(1) and R_(2).R_(1)(Ru^(Ⅱ)-(tpz)Cl_(2))features tetradentate ligands(tpz,6,6'-di(1H-pyrazol-1-yl)-2,2'-bipyridine)enforcing quasi-octahedral geometry;R_(2)(Ru^(Ⅱ)-(bpp)_(2))incorporates tridentate ligands(bpp,2,6-di(1H-pyrazol-1-yl)pyridine)inducing pronounced geometric distortion.The planar ligand(tpz)in R_(1) facilitates ordered molecular assembly through high conformational rigidity and extensive π-π stacking,resulting in increased molecular densities and enhanced morphological uniformity compared to R_(2) metallopolymers.Due to pyrazole’s weaker π-acceptance and strongerσ-donation compared to pyridine,R_(1) exhibits a 119 nm red-shift in metal-to-ligand charge transfer(MLCT)band and a 30 mV anodic shift in Ru^(+2/+3)redox potential relative to R_(2).Coupled with a reduced HOMO-LUMO gap,the uniform and ordered structure leads to a lower conductance decay constant in R_(1).Additionally,R_(2) metallopolymers exhibit superior memristive performance(characterized by lower switching voltage and higher switching ratio)via redox-induced aromatic transitions in axial ligands enhancing electronic delocalization.This work compares two metallopolymers with different ligand geometries,revealing how this difference leads to distinct charge transport and memristive behaviors.
基金Supported by the National Natural Science Foundation of China(Nos.52293472,22473096 and 22471164)。
文摘Among various architectures of polymers,end-group-free rings have attracted growing interests due to their distinct physicochemical performances over the linear counterparts which are exemplified by reduced hydrodynamic size and slower degradation.It is key to develop facile methods to large-scale synthesis of polymer rings with tunable compositions and microstructures.Recent progresses in large-scale synthesis of polymer rings against single-chain dynamic nanoparticles,and the example applications in synchronous enhancing toughness and strength of polymer nanocomposites are summarized.Once there is the breakthrough in rational design and effective large-scale synthesis of polymer rings and their functional derivatives,a family of cyclic functional hybrids would be available,thus providing a new paradigm in developing polymer science and engineering.
基金financially supported by the Sichuan Science and Technology Program(2022YFS0025 and 2024YFFK0133)supported by the“Fundamental Research Funds for the Central Universities of China.”。
文摘Tactile perception plays a vital role for the human body and is also highly desired for smart prosthesis and advanced robots.Compared to active sensing devices,passive piezoelectric and triboelectric tactile sensors consume less power,but lack the capability to resolve static stimuli.Here,we address this issue by utilizing the unique polarization chemistry of conjugated polymers for the first time and propose a new type of bioinspired,passive,and bio-friendly tactile sensors for resolving both static and dynamic stimuli.Specifically,to emulate the polarization process of natural sensory cells,conjugated polymers(including poly(3,4-ethylenedioxythiophen e):poly(styrenesulfonate),polyaniline,or polypyrrole)are controllably polarized into two opposite states to create artificial potential differences.The controllable and reversible polarization process of the conjugated polymers is fully in situ characterized.Then,a micro-structured ionic electrolyte is employed to imitate the natural ion channels and to encode external touch stimulations into the variation in potential difference outputs.Compared with the currently existing tactile sensing devices,the developed tactile sensors feature distinct characteristics including fully organic composition,high sensitivity(up to 773 mV N^(−1)),ultralow power consumption(nW),as well as superior bio-friendliness.As demonstrations,both single point tactile perception(surface texture perception and material property perception)and two-dimensional tactile recognitions(shape or profile perception)with high accuracy are successfully realized using self-defined machine learning algorithms.This tactile sensing concept innovation based on the polarization chemistry of conjugated polymers opens up a new path to create robotic tactile sensors and prosthetic electronic skins.
基金financially supported by the National Natural Science Foundation of China(Nos.52203135 and 52273206)Postdoctoral Fellowship Program of CPSF(No.GZC20230372)+4 种基金Huzhou Science and Technology Program Projects(No.2023GZ18)Zhejiang Postdoctoral Research Project(No.ZJ2023133)Science and Technology Cooperation Fund Program of Chengdu-Chinese Academy of ScienceHunan Provincial Natural Science Foundation(No.2021JJ10029)Huxiang High-level Talent Gathering Project(No.2022RC4039)。
文摘Organisms are capable of self-growth through the integration of the nutrients provided by the external environment.This process slows down when they grow.In this study,we mimicked this self-regulated growth via a simple swelling-polymerization strategy in which the stretching polymer chains in the original networks provide entropic elasticity to restrict growth in high growth cycles.Using typical covalently crosslinked polymers,such as acrylamide-based hydrogels and HBA-based elastomers,as examples,we demonstrate that the crosslinked polymers can absorb polymerizable compounds through a swelling-polymerization process to expand their sizes,but the growth extent becomes smaller with increasing growth cycle until reaching a plateau.In addition to their size,these materials become stiffer and exhibit less swelling ability in solvents.Our work not only provides a new growing mode to tune the properties of crosslinked polymers but also discloses the underlying mechanism of crosslinked polymers in multi-cyclic swelling conditions.
基金financially supported by the National Natural Science Foundation of China(Nos.52233001,51927805,and 52173110)the Innovation Program of Shanghai Municipal Education Commission(No.2023ZKZD07)the Shanghai Rising-Star Program(No.22QA1401200)。
文摘Cholesteric liquid crystals(CLCs)exhibit unique helical superstructures that selectively reflect circularly polarized light,enabling them to dynamically respond to environmental changes with tunable structural colors.This dynamic color-changing capability is crucial for applications that require adaptable optical properties,positioning CLCs as key materials in advanced photonic technologies.This review focuses on the mechanisms of dynamic color tuning in CLCs across various forms,including small molecules,cholesteric liquid crystal elastomers(CLCEs),and cholesteric liquid crystal networks(CLCNs),and emphasizes the distinct responsive coloration each structure provides.Key developments in photochromic mechanisms based on azobenzene,dithienylethene,and molecular motor switches,are discussed for their roles in enhancing the stability and tuning range of CLCs.We examine the color-changing behaviors of CLCEs under mechanical stimuli and CLCNs under swelling,highlighting the advantages of each form.Following this,applications of dynamic color-tuning CLCs in information encryption,adaptive camouflage,and smart sensing technologies are explored.The review concludes with an outlook on current challenges and future directions in CLC research,particularly in biomimetic systems and dynamic photonic devices,aiming to broaden their functional applications and impact.
文摘Internal rotation of conjugated organic backbone seriously impaired room temperature phosphorescence(RTP),leading to rare realization of ultra-long afterglows with RTP lifetimes over 2 s in non-bibulous polymers.Herein,N-(bromophenyl)carbazoles are cyclized to lock up phenyl-carbazol internal rotation in advance and the fused nitrogen hetero-cyclic compounds are doped into poly(methyl methacrylate)(PMMA).The results show that locking up the molecular internal rotation can achieve ultra-long RTP polymers with lifetimes over 2 s,in contrast,the unlocked molecules hardly emit RTP in PMMA.The high-lying triplet excitons can transfer the energy to low-lying organic fluorescent dyes,and the persistent multicolor afterglows including white emission can be readily modulated.This work discloses an effective and extendable dopant molecular strategy for developing high-performance ultra-long organic RTP polymers.
基金supported by the National Natural Science Foundation of China(Nos.223B2119,U23A2083,52373014,52203129).
文摘The facile synthesis of high-valued polymers from waste molecules or low-cost common chemicals presents a significant challenge.Here,we develop a series of degradable poly(thiocarbonate)s from the new step-growth polymerization of diols,carbonyl sulfide(CoS,or carbon disulfide,CS_(2)),and dichlorides.Diols and dichlorides are common chemicals,and CoS(CS_(2))is released as industrial waste.In addition to abun-dant feedstocks,the method is efficient and performed under mild conditions,using common organic bases as catalysts,and affording unprece-dented polymers.When cos,diols,and dihalides were used as monomers,optimized conditions could completely suppress the oxygen-sulfur exchange reaction,enabling the efficient synthesis of well-defined poly(monothiocarbonate)s with melting points ranging from 48°C to 101°C.These polymers,which have a structure similar to polyethylene with low-density in-chain polar groups,exhibit remarkable toughness and ductili-ty that rival those of high-density polyethylene(melting point:90°C,tensile strength:21.6±0.7 MPa,and elongation at break:576%).Moreover,the obtained poly(monothiocarbonate)s can be chemically degraded by alcoholysis to yield small-molecule diols and dithiols.When CS_(2)was used in place of cos,a pronounced oxygen-sulfur exchange reaction occurred.By optimizing reaction condition,it was found that polymers with-S(C=O)S-and-S(C=S)S-as the main repeating units exhibited high thermal stability and crystallinity.Thus,a new approach for regulat-ing the structure of polythiocarbonates via the oxygen-sulfur exchange reaction is developed.Overall,the polymers hold great potential for green materials due to their facile synthesis,readily available feedstocks,excellent performance,and chemical degradability.
基金financially supported by the National Natural Science Foundation of China(Nos.52373316,22075298,and52373020)the Beijing Municipal Natural Science Foundation(No.2212053)。
文摘Low dielectric constant(low-k)materials are critical for advanced packaging in high-density microelectronic devices and high-frequency communication technologies.Ladder polysiloxanes,which are characterized by their unique double-chain structure and intrinsic microporosity,offer remarkable advantages in terms of thermal stability,oxidation resistance,and dielectric performance.However,structural defects in ladder polysiloxanes,such as cage-like and irregular oligomers,and their effects on dielectric properties remain underexplored.In this study,a series of ladder-like polysiloxanes(X-TMS)with diverse side groups weresynthesized via a one-step base-catalyzed method.The influence of the benzocyclobutene(BCB)side groups on the formation of regular ladder structures was systematically investigated.Notably,BCB incorporation disrupted the structural regularity,favoring the formation of cage-like and irregular topologies,which were extensively characterized using 29silicon nuclear magnetic resonance spectroscopy(^(29)Si-NMR),Fourier transform infrared spectroscopy(FTIR),gel permeation chromatography(GPC),and X-ray diffraction(XRD).These structural defects were beneficial for improving the hydrophobicity and thermal stability.Copolymerization of X-TMS with commercial DVS-BCB resins further enhanced the mechanical properties,with the elastic modulus increasing from 3.6 GPa to 4.4 GPa and water absorption reduced from 0.33 wt%to 0.06 wt%.This study establishes a clear correlation between topological structures and material properties.These findings not only advance the understanding of the structure-property relationships in ladder polysiloxanes but also provide a novel approach for designing high-performance interlayer dielectric materials for next-generation microelectronics.
文摘Given the increasing demand for distributed electricity,there is a burning desire to harvest electricity from renewable sources using environmentally friendly methods.Thermoelectric (TE) materials can meet this requirement not only because of their ability to convert heat directly into electricity,enabling energy harvesting from waste heat and natural heat resources,but also because more than 60%of the energy is lost as waste heat [1].The discovery of the TE effect dates back to the 1820s when T.M.Seebeck observed electricity generation at the junction of two conductors with different temperatures.Additionally,when a voltage is applied to TE materials,they can create a temperature difference to enable solid-state cooling (known as the Peltier effect).Therefore,the TE effect promises both sustainable energy solutions and temperature control technologies.Over the past two decades,the urgent demand for powering ubiquitous Internet of Things devices has sparked significant interest in flexible thermoelectrics(F-TEs),which raises an intriguing question:Is the intrinsically flexible polymer an important candidate for state-of-the-art F-TEs applications?
基金supported by the National Natural Science Foundation of China(No.22273114)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB0770101)+1 种基金the National Key R&D Program of China(No.2023YFE0124500),the National Key R&D Program of China(No.2023YFC2411203)International Partnership Program of the Chinese Academy of Sciences(No.027GJHZ2022061FN)。
文摘Ring polymers are ubiquitous in various fields including biomaterials,drug release and gene therapy.All of these applications involve the dynamics and diffusion process of ring polymers in a confined environment.By using dynamic light scattering(DLS),we discovered a dynamical transition for charged ring polymers with increasing ring concentration in the gel matrix from a diffusive state to a non-diffusive topological frustrated state with a more compact conformation.When the ring polymer size is smaller than the mesh size of the gel matrix,the rings are diffusive at low concentration of 5 g/L.The ring diffusion coefficient in the gel matrix is an order of magnitude smaller than that of rings in solution,obeying the Ogston's model.At high ring concentration of 40 g/L,the collective dynamical behavior of the charged rings exhibits a topologically frustrated non-diffusive state,which may originate from the inter-ring threading with the external confinement from the gel matrix.Based on our previous theoretical work,we also conjectured that in such a non-diffusive state,the ring polymers might adopt a more compact conformation with the overall size exponentν=1/3.
基金financially supported by the National Key R&D Program of China(No.2021YFB3801901)the Institutional Research Fund from Sichuan University(No.2020SCUNL205)+1 种基金the Fundamental Research Funds for the Central Universitiesthe Higher Education Discipline Innovation Project(No.B20001)。
文摘Polymers that exhibit both biodegradability and chemical recyclability offer a promising solution to environmental pollution and resource scarcity. Poly(glycolic acid)(PGA) is a promising chemically recyclable polymer, characterized by its seawater degradability and high mechanical strength. In this study, aliphatic polycarbonates were synthesized through melt polycondensation and subsequently copolymerized with glycolide(GL) to produce chemically recyclable PGA based triblock copolymers with well-defined structures. The properties of these copolymers, including their thermal properties, crystallization behavior, and mechanical performance, can be effectively adjusted by modifying the structure and content of the middle block. Furthermore, an in-depth investigation reveals that the pyrolysis process involves ester exchange, radical, and back-biting reactions. In addition, the high-efficiency "Monomer↔Copolymer" chemical recycling loop has been established, achieving a remarkable yield exceeding 88% along with a purity greater than 99%.
基金funding from the National Natural Science Foundation of China(No.22401037)funding from JST CREST(No.JPMJCR23L1)。
文摘Chain-growth radical polymerization of vinyl monomers is essential for producing a wide range of materials with properties tailored to specific applications.However,the inherent resistance of the polymer's C―C backbone to degradation raises significant concerns regarding long-term environmental persistence,which also limits their potential in biomedical applications.To address these challenges,researchers have developed strategies to either degrade preexisting vinyl polymers or incorporate cleavable units into the backbone to modify them with enhanced degradability.This review explores the various approaches aimed at achieving backbone degradability in chain-growth radical polymerization of vinyl monomers,while also highlighting future research directions for the development of application-driven degradable vinyl polymers.
基金the National Key R&D Program of China(No.2022YFB3707303)National Natural Science Foundation of China(No.52293471)。
文摘Understanding the conformational characteristics of polymers is key to elucidating their physical properties.Cyclic polymers,defined by their closed-loop structures,inherently differ from linear polymers possessing distinct chain ends.Despite these structural differences,both types of polymers exhibit locally random-walk-like conformations,making it challenging to detect subtle spatial variations using conventional methods.In this study,we address this challenge by integrating molecular dynamics simulations with point cloud neural networks to analyze the spatial conformations of cyclic and linear polymers.By utilizing the Dynamic Graph CNN(DGCNN)model,we classify polymer conformations based on the 3D coordinates of monomers,capturing local and global topological differences without considering chain connectivity sequentiality.Our findings reveal that the optimal local structural feature unit size scales linearly with molecular weight,aligning with theoretical predictions.Additionally,interpretability techniques such as Grad-CAM and SHAP identify significant conformational differences:cyclic polymers tend to form prolate ellipsoid shapes with pronounced elongation along the major axis,while linear polymers show elongated ends with more spherical centers.These findings reveal subtle yet critical differences in local conformations between cyclic and linear polymers that were previously difficult to discern,providing deeper insights into polymer structure-property relationships and offering guidance for future polymer science advancements.
基金financially supported by National Key R&D Program of China(No.2021YFA1501700)CAS Project for Young Scientists in Basic Research(No.YSBR-094)+1 种基金Natural Science Foundation of Anhui Province(Nos.2308085Y35 and 2023AH030002)Hefei Natural Science Foundation(No.202304)。
文摘As a powerful synthetic tool,ruthenium-catalyzed ring-opening metathesis polymerization(ROMP)has been widely utilized to prepare diverse heteroatom-containing polymers.In this contribution,we report the synthesis of the novel imine-based polymer through the copolymerization of cyclooctene with cyclic imine comonomer via ROMP.Because of the efficient hydrolysis reactions of the imine group,the generated copolymer can be easily degraded under mild condition.Moreover,the generated degradable product was the telechelic polymer bearing amine group,which was highly challenged for its direct synthesis.And this telechelic polymer could also be used for the further synthesis of new polymer through post-transformation.The introduction of imine unit in this work provides a new example of the degradable polymer synthesis.
基金the Franco-Thai Cooperation Programme in Higher Education and Research(Franco-Thai Mobility Programme/PHC SIAM)Year 2024-2025。
文摘This study reviews light-responsive polymers in various applications,including drug delivery,information storage,sensor,self-healing material,antibacterial or anti-fouling,and environmental applications.Light-responsive polymers are a new material type being developed for various medical,electronics,engineering,and environmental applications.The working principle of light-responsive materials is based on metalligand interactions or non-covalent interactions between polymer functional groups,metal ions,and other filler functional groups.Light irradiation causes physical and mechanical changes in drug delivery and antibacterial systems,which results in the materials releasing more drugs or antibacterial substances.When materials in information storage devices and sensors are exposed to light,they can change color or glow.This has been applied for data storage to reveal QR codes under UV light.Additionally,this review discusses the thermodynamic aspects and computer modeling of light-responsive materials to emphasize the importance and development of these materials.Finally,light-responsive polymer development for various applications is presented.
基金National Natural Science Foundation of China No.22341302.
文摘The crystallization behavior of polymers is significantly influenced by molecular chain length and the dispersion of varying chain lengths.The complexity of studying crystallization arises from the dispersity of polymer materials and the typically slow cooling rates.Recent advancements in fast cooling techniques have rendered the investigation of polymer crystallization at varying cooling rates an attractive area of research;however,a systematic quantitative framework for this process is still lacking.We employ a coarse-grained model for polyvinyl alcohol(CGPVA)in molecular dynamics simulations to study the crystallization of linear polymers with varying chain lengths under variable cooling rates.Monodisperse,bidisperse and polydisperse samples are simulated.We propose two formulae based on a two-phase assumption to fit the exothermal curves obtained during cooling.Based on these formulae,better estimations of crystallization temperatures are obtained and the effects of chain lengths and cooling rates are studied.It is found that the crystallization temperature increases with chain length,similar to the Gibbs-Thomson relation formelting temperature,indicating a strong relation between fast crystallization and glass formation in linear polymers.Extrapolation to the infinitely slow cooling rate provides an easy way in simulations to estimate the equilibrium crystallization temperature.The effective chain lengths of polydisperse and bidisperse samples are found to be the number-averaged chain lengths compared to the weight-averaged ones.The chain length-dependent crystallization exhibits crossover behavior near the entanglement length,indicating the effects of entanglements under fast cooling conditions.The effect of chain length dispersity on crystallization becomes more obvious under fast cooling conditions.
基金supported by Beijing Natural Science Foundation(No.JQ22006)King Abdullah University of Science and Technology Research Funding(KRF)under Award(No.ORA-2021-CRG10-4668.4).
文摘Open-shell oligomers and polymers have exhibited intriguing electronic and magnetic properties, making them highly desirable for a wide range of applications, including ambipolar organic field-effect transistors (OFETs), photodetectors, organic thermoelectrics, and spintronics. Although open-shell ground states have been observed in certain small molecules and doped organic semiconductors, the exploration of open-shell ground-state conjugated polymers is still limited, and the strategies for designing these polymers remain obscure. This review aims to briefly introduce the theory and characterization methods of open-shell conjugated polymers, along with an overview of recent progress and applications. The objective is to stimulate further advancements and investigations in this promising area by shedding light on the potential of open-shell conjugated polymers and the challenges that lie ahead.
基金the National Natural Science Foundation of China(Nos.22075271,21625403,21875244 and 21875241)B.M.thanks the financial supports by State Key Laboratory of Polymer Physics and Chemistry,Changchun Institute of Applied Chemistry,Chinese Academy of Sciences and the Jilin Scientific and Technological Development Program(No.20220508142RC).
文摘The development of n-type polymer thermoelectrics lags far behind that of p-type ones in view of material diversity and performance.New structural insights into the thermoelectric performance are needed for efficient n-type polymer thermoelectric materials.Herein,we developed three acceptor-acceptor type organoboron polymers and investigated the effect of backbone configuration on thermoelectric performance.The three polymers are designed based on double B←N bridged bipyridine(BNBP)unit with monomeric thieno[3,4-c]pyrrole-4,6-dione(TPD),TPD dimer and TPD trimer as the copolymerizing units,respectively.The three polymers show similar low LUMO energy levels but different backbone configuration.Compared with the wavy backbone configuration,the pseudo-straight backbone configuration imparts the polymer with much enhanced crystallinity and electron mobility.As a result,after n-doping,the polymer with pseudo-straight configuration shows much higher electronic conductivity and power factor.We think these findings could serve as important guidelines for molecular design toward efficient n-type polymer thermoelectric materials.
文摘The coronavirus disease 2019 (COVID-19) pandemic has been at its worst and the world is fighting to help global public health. In this aspect the role played by polymers and polymeric materials including plastics as the main material in medical devices, personal protective equipment for health care workers is huge. Advantages like mass production, lower cost and possibilities for sterilization and disinfection of the plastic materials make them an inevitable material in healthcare sector. Apart from plastics, anti-viral and anti-microbial coatings, polymeric nanocomposites and functional polymers have been introduced as a helping tool against COVID-19. This review focuses on the application of polymers, and polymeric materials in COVID-19 pandemic. Usage of plastics and its applications in healthcare and related sectors have been reviewed. The major challenges faced and future prospects on the usage of polymers have also been discussed.
