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Wide bandgap steric carbazole-fluorene-nanogrid polymers via metal-free C-N polymerization for deep-blue polymer light-emitting diodes
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作者 Man Xu Qianyi Li +8 位作者 Jingyao Ma Hao Li Yunfei Zhu Fan Yu Kuande Wang Tao Zhou Quanyou Feng Linghai Xie Jinyi Lin 《Chinese Chemical Letters》 2026年第1期356-360,共5页
To precisely control intrachain π-electron delocalization and interchain interaction simultaneously is the prerequisite to obtain stable and efficient deep-blue light-emitting p-n polymer semiconductors for the polym... To precisely control intrachain π-electron delocalization and interchain interaction simultaneously is the prerequisite to obtain stable and efficient deep-blue light-emitting p-n polymer semiconductors for the polymer light-emitting diodes(PLEDs).Herein,we introduced the steric carbazole-fluorene nanogrid into light-emitting diphenyl sulfone-based p-n polymer semiconductors(PG and PDG) via metal-free C-N coupling polymerization for the fabrication of deep-blue PLEDs.The steric,rigid and twisted configuration between nanogrid and diphenyl sulfone in PG and PDG present the unique characteristic of large steric hindrance interaction to suppress interchain aggregation in solid state.Due to the different length of electron-deficient diphenyl sulfone monomers,PG showed a deep-blue emission with a maximum peak at 428 nm but red-shifted to 480 nm for the PDG films.Interestingly,similar deep-blue emission behavior of PG in diluted non-polar solution and films suggested the extremely weak interchain aggregation.Finally,PLEDs based on PG are fabricated with a stable deep-blue emission of CIE(0.15,0.10),and corresponding EL spectral profile is also completely identical to PL ones of diluted solution,revealed the intrachain emission without obvious interchain excited state,confirmed effectiveness of the steric hindrance functionalization of nanogrid in p-n polymer semiconductor for deep-blue light-emitting organic optoelectronics. 展开更多
关键词 p-n polymer semiconductors Metal-free C-N polymerization Steric carbazole-fluorene nanogrid Diphenyl sulfone Deep-blue polymer light-emitting diodes
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Star-shaped Block Copolymers of Poly-2-alkyl-5,6-dihydrooxazines:Synthesis,Conformational Characteristics,Thermoresponsiveness and Complexation with Curcumin
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作者 Tatyana U.Kirila Serafim V.Rodchenko +2 位作者 Nina D.Kozina Andrey V.Tenkovtsev Alexander P.Filippov 《Chinese Journal of Polymer Science》 2026年第2期423-436,I0012,共15页
Star-shaped six-arm polymers with hexaaza[2_(6)]orthoparacyclophane core and arms of block copolymers of poly-2-ethyl-5,6-dihydrooxazine with poly-2-isopropyl-5,6-dihydrooxazine were synthesized successfully using cat... Star-shaped six-arm polymers with hexaaza[2_(6)]orthoparacyclophane core and arms of block copolymers of poly-2-ethyl-5,6-dihydrooxazine with poly-2-isopropyl-5,6-dihydrooxazine were synthesized successfully using cationic ring-opening polymerization.The ratio of blocks,the order of their attachment to the core,and arm length were varied.Conformation of synthesized stars was determined by methods of molecular hydrodynamics and optics.It has been shown that star-shaped molecules were characterized by high intramolecular density,and the arm folding increased with their lengthening.The influence of the structure of block copolymers and their molar mass on the critical micelle concentration has been established.Complexes of synthesized star-shaped block copolymers with curcumin were obtained and the efficient binding of curcumin to polymer molecules was demonstrated.The behavior of the aqueous solutions of the prepared polymer stars and their complexes with curcumin was investigated by light scattering and turbidimetry methods.The influence of the structure and molar mass of star polymers on their thermoresponsiveness and the phase separation temperatures in aqueous solutions was analyzed.A slight increase in the phase separation temperature was found on passage from polymer solutions to solutions of polymer complexes with hydrophobic curcumin. 展开更多
关键词 Thermoresponsive star-shaped polymers Block copolymer of poly-2-alkyl-5 6-dihydrooxazine Aqueous solutions Complex of polymer with curcumin Phase separation
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The Magic of Organocatalytic Synergism in Switchable Polymerization:One-pot Synthesis of Block Copolymers with Programmable Sequences and Compositions
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作者 Shuai-Shuai Zhu Mao-Ji Zhao +1 位作者 Ying-Jie Yuan Yong Wang 《Chinese Journal of Polymer Science》 2026年第1期68-78,I0010,共12页
Switchable polymerization is emerging as a powerful tool to construct block copolymers directly from mixtures of monomers.However,current achievements typically iterate between two polymerization cycles to afford prod... Switchable polymerization is emerging as a powerful tool to construct block copolymers directly from mixtures of monomers.However,current achievements typically iterate between two polymerization cycles to afford products with fixed sequences and compositions.Herein,we report the triethylborane/1,8-diazabicyclo[5.4.0]undec-7-ene(Et_3B/DBU)pair-mediated four-component switchable polymerization of propylene oxide(PO),CO_(2),phthalic anhydride(PA),and racemic lactide(rac-LA),which enables the on-demand synthesis of four different block copolymers,i.e.,poly(propylene phthalate)-b-polylactide(PPE-b-PLA),PPE-b-PLA-b-poly(propylene carbonate)(PPC),PPE-b-PPC-b-PLA,and PPE-b-PPCb-poly(propylene oxide)(PPO),through rationally modulating the Lewis pair(LP)ratio.Core to this protocol is that increasing the loading of Et_(3)B accelerates the ring-opening of PO while impeding the reactivity of rac-LA,thus allowing for fine-tuning of the thermodynamic and kinetic of the switchable polymerization.Therefore,the four polymerization cycles involving PO/PA ring-opening copolymerization(ROCOP),PO/CO_(2) ROCOP,rac-LA ring-opening polymerization(ROP),and PO ROP can be connected and discriminated in precisely programmed manners. 展开更多
关键词 Switchable polymerization Organic Lewis pair Block copolymers Ring-opening copolymerization Multicomponent reaction
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A Comprehensive Review of the Functionalized Integrated Application of Gel Polymer Electrolytes in Electrochromic Devices
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作者 Lei Xu Leipeng Zhang +9 位作者 Dongqi Liu Zichen Ren Wenchao Liu Yike Zhang Yuqiang Wang Jiawu Sun Rui Yang Zekuo Lv Jiupeng Zhao Yao Li 《Nano-Micro Letters》 2026年第4期1-39,共39页
With the global push for energy conservation and the rapid development of low-power,flexible and wearable optical displays,the demand for electrochromic technology has surged.Gel polymer electrolytes(GPEs),a crucial c... With the global push for energy conservation and the rapid development of low-power,flexible and wearable optical displays,the demand for electrochromic technology has surged.Gel polymer electrolytes(GPEs),a crucial component of electrochromic devices(ECDs),show great promise in applications.This is attributed to their efficient ion-transport capabilities,excellent mechanical properties and strong adhesion.All of these characteristics are conducive to enhancing the safety of the devices,streamlining the packaging process,significantly improving the electrochromic performance of ECDs and boosting their commercial application potential.This review provides a comprehensive overview of GPEs for ECDs,focusing on their basic designs,functional modifications and practical applications.Firstly,this review outlines the fundamental design of GPEs for ECDs,encompassing key performance index,classification,gelation mechanism and preparation methods.Building on this foundation,it provides an in-depth discussion of functionalized GPEs developed to enhance device performance or expand functionality,including electrochromic,temperature-responsive,photo-responsive and stretchable self-healing GPE.Furthermore,the integration of GPEs into various ECD applications,including smart windows,displays,energy storage devices and wearable electronic,are summarized to highlight the advantages that the design of GPEs brings to the practical application of ECDs.Finally,based on the summary of GPEs employed for ECDs,the challenges and development expectations in this direction were indicated. 展开更多
关键词 Gel polymer electrolytes Electrochromic devices Multifunctional gels polymer designs
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Multi-dimensional optimization of polymer-involved Li^(+)solvation enabling stable polymer plastic crystal electrolyte for long-cycle lithium metal batteries
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作者 Lianzhan Huang Yuanlong Wu +6 位作者 Piao Luo Kexin Su Xin Song Mingdong Liu Minjian Li Huiyu Song Zhiming Cui 《Journal of Energy Chemistry》 2026年第1期656-665,I0015,共11页
Succinonitrile(SN)-based polymer plastic crystal electrolytes(PPCEs)are regarded as promising candidates for lithium metal batteries but suffer from serious side reactions with Li metal.Herein,we propose a multi-dimen... Succinonitrile(SN)-based polymer plastic crystal electrolytes(PPCEs)are regarded as promising candidates for lithium metal batteries but suffer from serious side reactions with Li metal.Herein,we propose a multi-dimensional optimization strategy to alleviate the side reactions between SN and Li metal,and develop a highly stable poly-vinylethylene carbonate-based PPCE(PPCE-VEC).Moreover,we identify the intrinsic factors of multi-dimensional polymer structures on the electrolyte stability by three typical classes of polyesters.The PPCE-VEC constructed by in situ polymerization exhibits much better stability than poly-vinylene carbonate-based PPCE(PPCE-VCA)and poly-trifluoroethyl acrylate-based PPCE(PPCE-TFA),which is verified by its fewer SN-decomposition species in X-ray photoelectron spectroscopy(XPS)and outstanding full cell performance.The PPCE-VEC-enabled LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)full cell achieve 73.7%capacity retention after 1400 cycles,which outperforms PPCE-VCA-and PPCE-TFA-enabled full cells(61.9%and 46.9%).Spectral analysis and theoretical calculation reveal that the high solvation ability of the carbonyl site,flexible polymer chain,and homogeneous electrolyte phase of PPCE-VEC are favorable to maximizing competition coordination with Li^(+)to weaken the Li^(+)–SN binding and shape an anion-rich solvation structure.This optimized polymer-involved Li^(+)solvation enhances SN stability and facilitates the formation of B/F enriched solid-electrolyte interphase(SEI),thus significantly improving PPCE stability. 展开更多
关键词 SUCCINONITRILE Li metal polymer plastic crystal electrolytes Multi-dimensional polymer structures
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Alkyl Alcohol Chain-length Mediated Steric Hindrance at Support Surface in Heterogeneous α-Diimine Ni Catalysts for Modulating Ethylene Polymerization
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作者 Fan Yu Bin Dai +2 位作者 Ning Liu Bin-Yuan Liu Chen Zou 《Chinese Journal of Polymer Science》 2026年第2期331-340,I0007,共11页
Heterogeneous polymerization represents a widely employed method in the polyolefin industry.In recent years,various heterogenization strategies for late transition metal catalysts have been developed,enabling effectiv... Heterogeneous polymerization represents a widely employed method in the polyolefin industry.In recent years,various heterogenization strategies for late transition metal catalysts have been developed,enabling effective control of polymer morphology and optimization of catalytic performance.However,while most studies have focused on designing anchoring groups and advancing support approaches,systematic investigations into how the support influences the catalytic behavior of the late transition metal catalysts.In this work,we fabricated supported α-diimine nickel catalysts by functionalizing the ligand with alkyl alcohol chains of varying lengths and supporting them onto MgCl_(2)supports.The ethylene polymerization behavior of these catalysts was then investigated.By precisely adjusting the alkyl alcohol chain length,the distance between the catalytically active metal center and the support surface was modulated.This approach demonstrates that support-induced steric hindrance effect can be effectively regulated by controlling the separation distance between the metal center and the support surface. 展开更多
关键词 Ethylene polymerization Ni catalysts Α-DIIMINE Heterogeneous polymerization POLYETHYLENE
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Ionic Hyper Crosslinked Polymers as High Performance Hemoperfusion Adsorbent for Efficient Removal of Excessive Bilirubin
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作者 Hong-Xiang Yin Yue-Yuan Xiao +7 位作者 Yu-Cheng Cai Shuai-Lin He Yang Wang Gang-Shen Zhang Cheng Zhang Bi-En Tan Irshad Hussain Wei Yan 《Chinese Journal of Polymer Science》 2026年第1期154-161,I0013,共9页
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
关键词 Porous organic polymers Hyper crosslinked polymers HEMOPERFUSION Bilirubin adsorption
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Recent Progresses in Synthesis of Cyclic Polymers in Large-scale and Some Functionalized Composites
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作者 QU Kairu GUO Lyuzhou +3 位作者 WANG Wenbin YAN Xuzhou CAO Xuezheng YANG Zhenzhong 《高等学校化学学报》 北大核心 2026年第1期42-57,共16页
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
关键词 Cyclic polymer Large-scale synthesis Single-chain nanoparticle Performance Composite
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An Emerging Liquid‑Crystalline Conducting Polymer Thermoelectrics:Opportunities and Challenges
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作者 Zhenqiang Ye Mingdong Zhang +3 位作者 Junyang Deng Lirong Liang Chunyu Du Guangming Chen 《Nano-Micro Letters》 2026年第3期240-273,共34页
Thermoelectric(TE)materials,being capable of converting waste heat into electricity,are pivotal for sustainable energy solutions.Among emerging TE materials,organic TE materials,particularly conjugated polymers,are ga... Thermoelectric(TE)materials,being capable of converting waste heat into electricity,are pivotal for sustainable energy solutions.Among emerging TE materials,organic TE materials,particularly conjugated polymers,are gaining prominence due to their unique combination of mechanical flexibility,environmental compatibility,and solution-processable fabrication.A notable candidate in this field is poly(2,5-bis(3-alkylthiophen-2-yl)thieno[3,2-b]thiophene)(PBTTT),a liquid-crystalline conjugated polymer,with high charge carrier mobility and adaptability to melt-processing techniques.Recent advancements have propelled PBTTT’s figure of merit from below 0.1 to a remarkable 1.28 at 368 K,showcasing its potential for practical applications.This review systematically examines strategies to enhance PBTTT’s TE performance through doping(solution,vapor,and anion exchange doping),composite engineering,and aggregation state controlling.Recent key breakthroughs include ion exchange doping for stable charge modulation,multi-heterojunction architectures reducing thermal conductivity,and proton-coupled electron transfer doping for precise Fermi-level tuning.Despite great progress,challenges still persist in enhancing TE conversion efficiency,balancing or decoupling electrical conductivity,Seebeck coefficient and thermal conductivity,and leveraging melt-processing scalability of PBTTT.By bridging fundamental insights with applied research,this work provides a roadmap for advancing PBTTT-based TE materials toward efficient energy harvesting and wearable electronics. 展开更多
关键词 Thermoelectric materials polymer PBTTT LIQUID-CRYSTALLINE
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Functional polymer materials containing heavy group-14 elements focusing on germanium and tin
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作者 Masayuki Gon Kazuo Tanaka 《Smart Molecules》 2026年第1期68-93,共26页
In this review,the synthesis,functions,and applications of the polymers containing germanium and tin,which are heavy group 14 elements,in their polymer frameworks are summarized.Germanium and tin can form similar skel... In this review,the synthesis,functions,and applications of the polymers containing germanium and tin,which are heavy group 14 elements,in their polymer frameworks are summarized.Germanium and tin can form similar skeletal structures with their homologues carbon and silicon,whereas the polymers containing germanium and tin show unique properties derived from their large atomic radii and weak binding energies.For example,polygermane and polystannane exhibited light absorption in the UV–visible region and conductivity because of theσ-conjugation through the polymer main-chain constructed byσ-bonds between heavy elements.Theσ-conjugation was affected by the conformational change of the polymer main-chain,and thermochromic properties can be induced.Furthermore,the weak bonds were able to be cleaved homolytically upon photoirradiation,and radicals were subsequently generated.By incorporating hypervalent heavy elements into theπ-conjugated system,it was possible to modulate the electronic structures of theπ-conjugated system throughσ*–π*conjugation with highly coordinated elements.Finally,applications for organic solar cells,organic lightemitting materials,and chemical sensors have been achieved.Herein,representative synthetic methods and unique properties for creating smart materials with germanium and tin will be explained. 展开更多
关键词 GERMANIUM heavy element polymer TIN
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Erratum to"Amine-reactive Polymer Platform for Engineering Surface Modification of Next-generation Sequencing Chips"
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作者 Wei Tian Xin-Yuan Wang +4 位作者 Die-Wen Feng Xiang-Qian Li Yue-Kang Jin Hui Li Hao Liu 《Chinese Journal of Polymer Science》 2026年第1期314-314,I0019,共2页
We are sorry for the mistakes of Affiliation,"a State Key Laboratory of Advanced Fiber Materials,Center for Advanced Low-Dimension Materials,Donghua University,Shanghai 201620,China"should be replaced by&quo... We are sorry for the mistakes of Affiliation,"a State Key Laboratory of Advanced Fiber Materials,Center for Advanced Low-Dimension Materials,Donghua University,Shanghai 201620,China"should be replaced by"a State Key Laboratory of Advanced Fiber Materials,Center for Advanced Low-Dimension Materials,College of Materials Science and Engineering,Donghua University,Shanghai 201620,China".We apologized for the inconvenience caused by this error. 展开更多
关键词 erratum surface modification affiliation next generation sequencing chips reactive polymer platform advanced fiber materialscenter
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Order Remains Interior to a Ceramic Ionic Nanocluster Sterically Hindered by Covalently Attached Polymer Segments
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作者 JIA Leiyu WU Junji +13 位作者 YU Zixin CHEN Yuan XU Yao WANG Jie HU Zhen HU Chuanqun DING Dachuan YANG Bin HU Tao GONG Xinghou WANG Juan ALBINA Jan-Michael WU Chonggang HARA Masanori 《Journal of Wuhan University of Technology(Materials Science)》 2026年第2期537-546,共10页
When a ceramic ionic-crystal nanocluster is group-substituted with polymer chain segments to form an ionomeric aggregate,is the ordered structure maintained within the sterically hindered nanocluster?We observed,for N... When a ceramic ionic-crystal nanocluster is group-substituted with polymer chain segments to form an ionomeric aggregate,is the ordered structure maintained within the sterically hindered nanocluster?We observed,for Na-salt sulfonated polystyrene ionomer,the electron-diffraction lattice fringes of the nanoclusters,which proved their internal crystalline ordering driven by electrostatic attractions overcoming steric hindrance.Kinetically,the nanoclusters'enhanced melting endotherm upon aging indicate their quasi-,slow-ordering character.Extended tight binding molecular dynamics simulations provide an insight into the mechanism underlying the ionic-group aggregation during nanoclustering.We hence proposed an uncommon state of order,polymer-bound ceramic quasicrystal,supplementary to the order phenomena in crystalline ceramics. 展开更多
关键词 ceramic ionic nanocluster polymer chain segment morphology order molecular dynamics simulation
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Constitutive modeling of solvent plasticization and physical aging in glassy polymers
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作者 Xu CAO Kerong WU +1 位作者 Ji LIN Rui XIAO 《Applied Mathematics and Mechanics(English Edition)》 2026年第3期535-554,共20页
Glassy polymers are widely used in biomedical applications in a solvent environment,yet their long-term performance is governed by the competing effects of physical aging and solvent-induced plasticization.Here,we dev... Glassy polymers are widely used in biomedical applications in a solvent environment,yet their long-term performance is governed by the competing effects of physical aging and solvent-induced plasticization.Here,we develop a constitutive model that explicitly couples the solvent concentration,structural relaxation,and mechanical response.This framework is built on a multiplicative decomposition of deformation and an Eyring-type flow rule,with structural evolution described by an effective temperature.A generalized shift factor is introduced to quantify how the solvent concentration and effective temperature jointly affect the relaxation time,thereby integrating physical aging and plasticization.The model is subsequently applied to methacrylate(MA)-based copolymer networks immersed in phosphate-buffered saline for up to nine months.Simulations accurately capture key experimental features,including the strong softening of highly swellable networks,the partial recovery due to aging,and the mitigating role of hydrophobic crosslinking in reducing solvent uptake.While the current single-mode description cannot reproduce the full relaxation spectrum,it establishes an efficient framework for predicting the long-term mechanical performance under coupled environmental and mechanical loading.This study provides a constitutive description of solvent-swollen glassy polymers,offering mechanistic insight into the interplay between plasticization and aging.Beyond biomedical MA networks,this framework establishes a foundation for predicting the long-term performance of polymer glasses under coupled aqueous environmental and mechanical loading. 展开更多
关键词 glassy polymer SWELLING physical aging constitutive model
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Chinese Journal of Polymer Science
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《Chinese Journal of Polymer Science》 2026年第2期I0001-I0003,共3页
Aims and Scope Chinese Journal of Polymer Science(CJPS)is a monthly journal published in English and sponsored by the Chinese Chemical Society and the Institute of Chemistry,Chinese Academy of Sciences.CJPS is edited ... Aims and Scope Chinese Journal of Polymer Science(CJPS)is a monthly journal published in English and sponsored by the Chinese Chemical Society and the Institute of Chemistry,Chinese Academy of Sciences.CJPS is edited by a distinguished Editorial Board headed by Professor Qi-Feng Zhou and supported by an International Advisory Board in which many famous active polymer scientists all over the world are included. 展开更多
关键词 Monthly Journal Chinese Academy Sciences polymer Science advisory board Institute Chemistry editorial board International Advisory Board Chinese Chemical Society
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Short-chain Length Dependence of Equilibrium Dynamics and Nonlinear Rheology in Unentangled Long-chain/Short-chain Polymer Blends
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作者 Xiao-Yang Wang Bo Liu +2 位作者 Li-Jia An Zhen-Hua Wang Yu-Yuan Lu 《Chinese Journal of Polymer Science》 2026年第2期525-535,I0016,共12页
The equilibrium dynamics and nonlinear rheology of unentangled polymer blends remain inadequately understood,especially regarding the influence of short-chain matrix length N_(S) on the structure and rheological behav... The equilibrium dynamics and nonlinear rheology of unentangled polymer blends remain inadequately understood,especially regarding the influence of short-chain matrix length N_(S) on the structure and rheological behavior of dispersed long chains.Using molecular dynamics simulations based on the Kremer-Grest model,we systematically explore the N_(S)-dependence of static conformations,equilibrium dynamics,and nonlinear shear responses in unentangled long-chain/short-chain polymer blends.Our results demonstrate a decoupling between the static and dynamic sensitivity to N_(S):while the static chain size,R_g,follows Flory theory with slight swelling at small N_(S) due to incomplete excluded volume screening,the diffusion coefficient,D,and the relaxation time,τ_(0),exhibit a strong,non-monotonic N_(S)-dependence,transitioning from monomeric friction dominance at small N_(S) to collective segmental rearrangement at large N_(S).Additionally,we observe partial decoupling between the viscous and normal stress responses:while the zero-shear viscosity,η,is strongly N_(S)-dependent,the first and second normal stress coefficients,Ψ_(1) and Ψ_(2),collapse onto universal curves when scaled by the dimensionless shear rate,γτ_(0),suggesting a common mechanism of orientation and stretching.Under shear,long chains compress in the vorticity direction λ_(z)~Wi^(-0.2),which reduces collision frequency and contributes to shear thinning,while the scaling of weaker orientation resistance m_(G)~Wi^(0.35)reflects hydrodynamic screening by the short-chain matrix.These findings highlight the limitations of single-chain models and emphasize the necessity of considering N_(S)-dependent matrix dynamics and flow-induced structural changes in understanding the rheology of unentangled polymer blends. 展开更多
关键词 Unentangled polymer blend Nonlinear rheology Equilibrium dynamics Hydrodynamic interaction screening Molecular dynamics simulation
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Development of silicon carbide fiber-reinforced silicon oxycarbide composites for low-observable unmanned aerial vehicle exhaust nozzles via filament winding,and polymer infiltration and pyrolysis
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作者 Byeong-Joo Kim Ji Eun Lee +4 位作者 Chang-Bin Oh Doo Hyun Choi Man Young Lee Dae Young Jo Shin Kim 《Defence Technology(防务技术)》 2026年第2期49-65,共17页
Unmanned combat aerial vehicles require lightweight,stealth-capable exhaust systems.However,traditional metallic nozzles increase radar detectability and reduce range,while advanced composites offer high performance b... Unmanned combat aerial vehicles require lightweight,stealth-capable exhaust systems.However,traditional metallic nozzles increase radar detectability and reduce range,while advanced composites offer high performance but are expensive.Therefore,to improve the operational range and survivability of unmanned combat aerial vehicles,a lightweight,high-temperature-resistant,oxidation-resistant,and low-observable composite exhaust nozzle is developed to replace conventional metallic straight-type nozzles.The nozzle features a double serpentine shape to reduce radar and infrared signatures and is manufactured as a monolithic structure using the filament winding process,accommodating the complex geometry and large size(length:1.8 m,width:0.8 m).The exhaust nozzle consists of a ceramic matrix composite made of silicon carbide fibers and a silicon oxycarbide matrix,which absorbs and scatters radio frequency signals while withstanding prolonged exposure to high-temperature(700℃)oxidizing environments typical of engine exhaust gases.The polysiloxane resin used to produce the silicon oxycarbide matrix poses significant challenges owing to its low tackiness and high viscosity variations depending on the presence of nanoparticles,making filament winding difficult.These challenges are addressed by optimizing resin viscosity and winding pattern design.As a result,the tensile strength of the composite specimens fabricated with the optimized viscosity increases by 228.03% before pyrolysis and 97.68%after pyrolysis,compared with that of the non-optimized specimens.In addition,the density and tensile strength of the composite processed via three cycles of polymer infiltration and pyrolysis increased by 13.08% and 80.37%,respectively,compared to those of the non-densified composite.High-temperature oxidation and flame tests demonstrate exceptional thermal and oxidative stability.Furthermore,when compared with carbon fiber-reinforced ceramic matrix composites,the developed composite exhibits a permittivity at least two levels lower and a reflection loss below7 dB within the frequency range of 9.3-10.9 GHz,underscoring its superior electromagnetic stealth performance. 展开更多
关键词 Filament winding polymer infiltration and pyrolysis Ceramic matrix composites Exhaust nozzle Low observability
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Nonmonotonic Stress Overshoot in Entangled Polymer Melts under Two-step Shear
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作者 Yong-Jin Ruan Ya-Qing Chang +1 位作者 Jiang-Yang Mo Bai-Cheng Mei 《Chinese Journal of Polymer Science》 2026年第1期268-277,I0018,共11页
Shear stress overshoot in entangled polymer rheology is a hallmark of transient dynamics,but its microscopic origin remains under debate.Using molecular dynamics simulations,we investigate a two-step shear protocol co... Shear stress overshoot in entangled polymer rheology is a hallmark of transient dynamics,but its microscopic origin remains under debate.Using molecular dynamics simulations,we investigate a two-step shear protocol consisting of successive startup shears separated by a waiting period,with the first shear interrupted before the overshoot.In the homogeneous flow,the GLaMM theory captures the stress response during the first shear,but fails to reproduce the nonmonotonic dependence of the second stress overshoot(σ_(2max))on the waiting time.Contrary to the prediction of a nonmonotonic normal stress component σ_(yy)during the waiting period,our simulations show that σ_(yy),like the tube segment orientation(S_(xy)),the contour length of the primitive chain(L),and the entanglement number per chain(Z),relaxes monotonically toward equilibrium.At the strain corresponding to σ_(2max),both the tube segment orientation and the entanglement number per chain exhibit a nonmonotonic dependence on the waiting time that closely mirrors the behavior of σ_(2max),indicating that both factors play significant roles in governing(σ_(2max).Our findings are consistent with the interpretation of lanniruberto and Ma rrucci[ACS Macro.Lett.2014,3,552]for orientation effects and with the viewpoint of Wang et al.[Macromolecules 2013,46,3147]for entanglement effects,although the two explanations are rooted in distinct physical pictu res.These results provide new insights into the stress responses of entanglement polymer fluids and underscore the need for a more unified theoretical framework. 展开更多
关键词 Entangled polymer rheology Molecular dynamics simulation Tube model DISENTANGLEMENT
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Deterioration and Pore Structure Evolution of GO Modified Polymer Cement Mortar under Salt-freeze-thaw Coupling Effects
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作者 ZHAO Xinyuan WEI Zhiqiang +3 位作者 QIAO Hongxia LI Shaofei CAO Hui XI Lingling 《Journal of Wuhan University of Technology(Materials Science)》 2026年第1期234-246,共13页
To investigate the pore structure of graphene oxide modified polymer cement mortar(GOPM)under salt-freeze-thaw(SFT)coupling effects and its impact on deterioration,this study modifies polymer cement mortar(EMCM)with g... To investigate the pore structure of graphene oxide modified polymer cement mortar(GOPM)under salt-freeze-thaw(SFT)coupling effects and its impact on deterioration,this study modifies polymer cement mortar(EMCM)with graphene oxide(GO).The micro-pore structure of GOPM is characterized using LF-NMR and SEM.Fractal theory is applied to calculate the fractal dimension of pore volume,and the deterioration patterns are analyzed based on the evolution characteristics of capillary pores.The experimental results indicate that,after 25 salt-freeze-thaw cycles(SFTc),SO2-4 ions penetrate the matrix,generating corrosion products that fill existing pores and enhance the compactness of the specimen.As the number of cycles increases,the ongoing formation and expansion of corrosion products within the matrix,combined with persistent freezing forces,and result in the degradation of the pore structure.Therefore,the mass loss rate(MLR)of the specimens shows a trend of first decreasing and then increasing,while the relative dynamic elastic modulus(RDEM)initially increases and then decreases.Compared to the PC group specimens,the G3PM group specimens show a 28.71% reduction in MLR and a 31.42% increase in RDEM after 150 SFTc.The fractal dimensions of the transition pores,capillary pores,and macropores in the G3PM specimens first increase and then decrease as the number of SFTc increases.Among them,the capillary pores show the highest correlation with MLR and RDEM,with correlation coefficients of 0.97438 and 0.98555,respectively. 展开更多
关键词 graphene oxide polymer cement mortar pore structure fractal dimension
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Lithium-Ion Dynamic Interface Engineering of Nano-Charged Composite Polymer Electrolytes for Solid-State Lithium-Metal Batteries
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作者 Shanshan Lv Jingwen Wang +7 位作者 Yuanming Zhai Yu Chen Jiarui Yang Zhiwei Zhu Rui Peng Xuewei Fu Wei Yang Yu Wang 《Nano-Micro Letters》 2026年第2期288-305,共18页
Composite polymer electrolytes(CPEs)offer a promising solution for all-solid-state lithium-metal batteries(ASSLMBs).However,conventional nanofillers with Lewis-acid-base surfaces make limited contribution to improving... Composite polymer electrolytes(CPEs)offer a promising solution for all-solid-state lithium-metal batteries(ASSLMBs).However,conventional nanofillers with Lewis-acid-base surfaces make limited contribution to improving the overall performance of CPEs due to their difficulty in achieving robust electrochemical and mechanical interfaces simultaneously.Here,by regulating the surface charge characteristics of halloysite nanotube(HNT),we propose a concept of lithium-ion dynamic interface(Li^(+)-DI)engineering in nano-charged CPE(NCCPE).Results show that the surface charge characteristics of HNTs fundamentally change the Li^(+)-DI,and thereof the mechanical and ion-conduction behaviors of the NCCPEs.Particularly,the HNTs with positively charged surface(HNTs+)lead to a higher Li^(+)transference number(0.86)than that of HNTs-(0.73),but a lower toughness(102.13 MJ m^(-3)for HNTs+and 159.69 MJ m^(-3)for HNTs-).Meanwhile,a strong interface compatibilization effect by Li^(+)is observed for especially the HNTs+-involved Li^(+)-DI,which improves the toughness by 2000%compared with the control.Moreover,HNTs+are more effective to weaken the Li^(+)-solvation strength and facilitate the formation of Li F-rich solid-electrolyte interphase of Li metal compared to HNTs-.The resultant Li|NCCPE|LiFePO4cell delivers a capacity of 144.9 m Ah g^(-1)after 400 cycles at 0.5 C and a capacity retention of 78.6%.This study provides deep insights into understanding the roles of surface charges of nanofillers in regulating the mechanical and electrochemical interfaces in ASSLMBs. 展开更多
关键词 Charged nanofillers Nanocomposite polymer electrolyte Dynamic lithium ion interface Solid ion-conductors Solidstate lithium-metal battery
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Tailoring Dielectric Properties of Polymer Matrix Composites for High-performance Flexible Sensors
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作者 Jun Li Kit-Ming Ma +1 位作者 Li-Sha Zhang Xiao-Ming Tao 《Chinese Journal of Polymer Science》 2026年第1期116-126,I0012,共12页
Polymer matrix composites with high dielectric constants and low dielectric losses are in high demand for flexible electronics.However,simultaneously satisfying these requirements poses a significant scientific challe... Polymer matrix composites with high dielectric constants and low dielectric losses are in high demand for flexible electronics.However,simultaneously satisfying these requirements poses a significant scientific challenge owing to the intrinsic trade-off relationship.Herein,we utilized the in situ controllable reduction of graphene oxide(GO)within a poly(vinylidene fluoride-trifluoroethylene-chlorofluoroethylene)(P(VDF-Tr FE-CFE))matrix to regulate the dielectric properties.The as-obtained composite exhibited a high relative dielectric constant of 1415coupled with a low loss tangent of 0.380 at 100 Hz.Experimental and theoretical studies indicate that the increased degree of electron conjugation and conductivity of the reduced GO(RGO)are responsible for the high-k.The constrained reduction degree of GO,combined with its homogeneous dispersion in the polymer matrix,effectively suppresses long-range charge carrier migration,thereby minimizing dielectric loss.This novel strategy could be successfully applied to both organic and aqueous systems.Furthermore,a high-performance flexible capacitive proximity sensor was exemplified by the optimization of both the dielectric layer and electrode pattern,exhibiting excellent sensitivity and stability.The fundamental mechanisms elucidated in this study provide crucial design principles for developing dielectric PMCs with tailored properties,thereby opening new avenues for advanced flexible electronic applications. 展开更多
关键词 Dielectric property regulation HIGH-K polymer matrix composites(PMCs) Capacitive proximity sensor
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