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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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Functionally Oriented Tumor Microenvironment Responsive Polymeric Nanoassembly:Engineering and Applications 被引量:5
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作者 Wen-Ming Zhang Jian Zhang +1 位作者 Zhu Qiao Jun Yin 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2018年第3期273-287,共15页
The excellent drug encapsulation,prolonged in vivo circulation time,enhanced pharmacokinetics,and reduced adverse effects make the polymeric assemblies ideal carriers in nanomedicine,and become an emerging research fi... The excellent drug encapsulation,prolonged in vivo circulation time,enhanced pharmacokinetics,and reduced adverse effects make the polymeric assemblies ideal carriers in nanomedicine,and become an emerging research field with rapid development.In vivo,the polymer nanoassemblies will experience five steps,including circulation in the blood,accumulation in the tumoral site,penetration into the deep tumor tissue to reach cancer cells,internalization into cancer cells,and intracellular drug release.However,although tremendous efforts have been made to the material design,currently available carriers still have difficulties in fulfilling all of the requirements.Moreover,the long-standing dilemma of the synchronized stability and permeability of vesicles is still a big challenge,which confused researchers for a long time.This feature article tbcuses on the recent progress of single-or multi-stimuli triggered theranostic platforms,and the extracellularly reengineered shell-sheddable polymeric nanocarriers are systematically discussed.The perspectives for future developments in the nanocarriers functioned with artificial helical polymers(the potential cell-penetrating peptides mimics)are also proposed.We speculate that this feature article can fit the interesting of diverse readers and a guideline for the design of next generation of drug nanocarriers. 展开更多
关键词 Block copolymers Tumor microenvironment responsive SELF-ASSEMBLY THERANOSTIC NANOMEDICINE
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Histidine N-Thiocarboxyanhydride:Direct Synthesis and Polymerization without Protection towards Well-defined Polyhistidine 被引量:1
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作者 Song-Yi Xu Tian-Wen Bai +2 位作者 Bo-Tuo Zheng Ze-Hua Li Jun Ling 《Chinese Journal of Polymer Science》 2025年第8期1311-1319,共9页
Consisting of natural histidine residues,polyhistidine(PHis)simulates functional proteins.Traditional approaches towards PHis require the protection of imidazole groups before monomer synthesis and polymerization to p... Consisting of natural histidine residues,polyhistidine(PHis)simulates functional proteins.Traditional approaches towards PHis require the protection of imidazole groups before monomer synthesis and polymerization to prevent degradation and side reactions.In the contribution,histidine N-thiocarboxyanhydride(His-NTA)is directly synthesized in aqueous solution without protection.With the self-catalysis of the imidazole side group,the ring-closing reaction to form His-NTA does not require any activating reagent(e.g.,phosphorus tribromide),which is elucidated by density functional theory(DFT)calculations.His-NTA directly polymerizes into PHis bearing unprotected imidazole groups with designable molecular weights(4.2-7.7 kg/mol)and low dispersities(1.10-1.19).Kinetic experiments and Monte Carlo simulations reveal the elementary reactions and the relationship between the conversion of His-NTA and time during polymerization.Block copolymerization of His-NTA with sarcosine N-thiocarboxyanhydride(Sar-NTA)demonstrate versatile construction of functional polypept(o)ides.The triblock copoly(amino acid)PHis-b-PSar-b-PHis is capable to reversibly coordinate with transition metal ions(Fe^(2+),Co^(2+),Ni^(2+),Cu^(2+)and Zn^(2+))to form pH-sensitive hydrogels. 展开更多
关键词 N-thiocarboxyanhydride Polyhistidine Controlled ring-opening polymerization POLYPEPTIDE Poly(amino acid)s
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Refractive Index Engineering as a Novel Strategy toward Highly Transparent and Tough Sustainable Polymer Blends 被引量:4
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作者 Si-Ting Sun Hang Wang +6 位作者 Dong Huang Ying-Li Ding Yang Zhang Dong-Po Song Kun-Yu Zhang Li Pan Yue-Sheng Li 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2020年第12期1335-1344,共10页
High transparency and toughness are prerequisites for sustainable polymers if they are to find wide application as alternatives to petroleum-based polymers.However,the utility of sustainable polymers such as commercia... High transparency and toughness are prerequisites for sustainable polymers if they are to find wide application as alternatives to petroleum-based polymers.However,the utility of sustainable polymers such as commercially available polylactide(PLA)is limited by their inherent brittleness and high cost.Unfortunately,toughening PLA-based materials via cost-effective blending strategies without sacrificing transparency remains a challenge.Herein,we report a novel strategy involving active refractive index matching for creation of highly transparent and tough PLA blends.Specifically,we engineered the refractive index of a promising renewable poly(epichlorohydrin-co-ethylene oxide)elastomer by introducing polar ionic moieties via a simple chemical method,and we blended the resulting ionomers with PLA.The best blend showed an impact strength of>80 kJ/m2,an elongation at break of 400%,and high transparency(90%).These characteristics are of great importance for potential applications such as packaging.Our strategy offers a versatile new way to prepare high-performance sustainable polymer materials with excellent transparency. 展开更多
关键词 POLYLACTIDE Blending strategies Refraaive index matching Poly(epichlorohydrin-co-ethylene oxide) IONOMERS
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Poly(thiocarbonate)Synthesis from Carbonyl Sulfide(or Carbon Disulfide),Diol,and Dichlorides:A Step Growth Route to PE-like Sulfur-containing Polymers
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作者 Yue Sun Yu-Xiang Cao +5 位作者 Hao-Xuan Huang Shu-Zhe Shen Yan-Ni Xia Tong Shao Cheng-Jian Zhang Xing-Hong Zhang 《Chinese Journal of Polymer Science》 2025年第10期1774-1784,共11页
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
关键词 Poly(thiocarbonate)s Step-growth polymerization CoS(CS_(2)) Oxygen-sulfur exchange reaction
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Gel polymer electrolyte for flexible and stretchable lithium metal battery:Advances and prospects
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作者 Hongfei Li Hao Chen +3 位作者 Qi Kang Lihe Guo Xingyi Huang Haiping Xu 《Chinese Chemical Letters》 2025年第9期256-268,共13页
Flexible and stretchable energy storage devices are highly desirable for wearable electronics,particularly in the emerging fields of smart clothes,medical instruments,and stretchable skin.Lithium metal batteries(LMBs)... Flexible and stretchable energy storage devices are highly desirable for wearable electronics,particularly in the emerging fields of smart clothes,medical instruments,and stretchable skin.Lithium metal batteries(LMBs) with high power density and long cycle life are one of the ideal power sources for flexible and stretchable energy storage devices.However,the current LMBs are usually too rigid and bulky to meet the requirements of these devices.The electrolyte is the critical component that determines the energy density and security of flexible and stretchable LMBs.Among various electrolytes,gel polymer electrolytes(GPEs) perform excellent flexibility,safety,and high ionic conductivity compared with traditional liquid electrolytes and solid electrolytes,fulfilling the next generation deformable LMBs.This essay mainly reviews and highlights the recent progress in GPEs for flexible/stretchable LMBs and provides some useful insights for people interested in this field.Additionally,the multifunctional GPEs with self-healing,flame retardant,and temperature tolerance abilities are summarized.Finally,the perspectives and opportunities for flexible and stretchable GPEs are discussed. 展开更多
关键词 Wearable electronic Lithium metal batteries Gel polymer electrolyte FLEXIBLE STRETCHABLE
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Ring Opening Polymerization ofω-Pentadecalactone by Weakly Oxophilic Fe(II)-based Catalytic Systems Bearing Bulkyα-Diimine Ligands
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作者 Li-Jia Liu Wen-Peng Zhao +4 位作者 Li-Shuang Ma Chun-Yu Zhang Feng Wang Xue-Quan Zhang Heng Liu 《Chinese Journal of Polymer Science》 2025年第4期640-654,共15页
High catalytic efficiencies in ring opening polymerization(ROP)of a large ring-sized macrolactone,ω-pentadecalactone(PDL),by using transition metal Fe(II)-based catalysts were achieved for the first time in this stud... High catalytic efficiencies in ring opening polymerization(ROP)of a large ring-sized macrolactone,ω-pentadecalactone(PDL),by using transition metal Fe(II)-based catalysts were achieved for the first time in this study.Benefited from the bulky nature of the ligatedα-diimine ligands,as evidenced from single-crystal structures,as well as the weakly oxophilic nature of the metal centers,chain transesterification reactions could be partially suppressed,allowing the polymerization proceed in a living-like and semi-controllable manner,i.e.good linear dependence of propagation rates on catalyst concentration and PDL concentration as observed in the detailed kinetics studies.The whole polymerization proceeds via a“coordination-insertion”mechanism,and with the aid of density functional theory(DFT)calculation studies,a“slow insertion→fast elimination”manner was demonstrated for the monomer propagation step,suggesting the insertion of Fe-OR into the carbonyl group C=O as the rate-determining step.The present catalytic system also showed fast chain transfer reactions to alcohol compounds,affording quasi-immortal characteristics.DFT calculations showed that such a transfer reaction only required an energy barrier of 6.4 kcal/mol,performing a good consistency with the fast chain transfer rates. 展开更多
关键词 ω-Pentadecalactone Ring opening polymerization Polyester Ferrous catalysts
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Engineering tiramisu-like phase change nanocomposite for superior thermal energy management and electromagnetic interference shielding
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作者 Boyang Hu Hong Guo +5 位作者 Ting Li Xiwei Cao Min Cao Weiyan Qi Ying Cui Baoan Li 《Journal of Materials Science & Technology》 2025年第3期113-124,共12页
Exploiting advanced nanocomposites isochronally integrating outstanding thermal conductivity(TC)and electromagnetic interference shielding effectiveness(EMI SE)can boost the cutting-edge application of phase change ma... Exploiting advanced nanocomposites isochronally integrating outstanding thermal conductivity(TC)and electromagnetic interference shielding effectiveness(EMI SE)can boost the cutting-edge application of phase change materials.Here,we report a tiramisu-like composite(GMP),where the typical“crust-and-cheese”hierarchical structure is replicated by an innovative two-step bidirectional freezing assembly(BFA)and compressive densification.Hierarchical-aligned graphene array(G-GA)with ultralow thermal resistance is fabricated through 1st BFA and graphitization.During the 2nd BFA,the MXene-CNF crosslinking network with hydrogen-bond actions is used for encapsulating polyethylene glycol(PEG)onto the microlayers of the G-GA skeleton.Remarkably,the microlaminated GMP4 achieves a recorded TC of 34.05 W m^(-1) K^(-1),unprecedented EMI SE of 87.4 dB,and preferable enthalpy density of 179.4 J cm^(-3),along with leakage-free function,and eminent thermal durability.Furthermore,the GMP-loaded equipment is demonstrated for efficient microelectronics cooling and sustainable solar energy utilization.This work opens new avenues for multiscale designing multifunctional macro-composites,broadening the application prospects in advanced electronics and solar energy utilization systems. 展开更多
关键词 Phase change composite Multiscale structure construction Bidirectional freezing assembly Thermal management EMI shielding
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Tissue Engineering in Neuroscience: Applications and Perspectives
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作者 Xiaoge Zhang Fuyao Liu Zhen Gu 《Biomedical Engineering Frontiers》 CAS 2023年第1期247-259,共13页
Neurological disorders have always been a threat to human physical and mental health nowadays,which are closely related to the nonregeneration of neurons in the nervous system(NS).The damage to the NS is currently dif... Neurological disorders have always been a threat to human physical and mental health nowadays,which are closely related to the nonregeneration of neurons in the nervous system(NS).The damage to the NS is currently difficult to repair using conventional therapies,such as surgery and medication.Therefore,repairing the damaged NS has always been a vast challenge in the area of neurology.Tissue engineering(TE),which integrates the cell biology and materials science to reconstruct or repair organs and tissues,has widespread applications in bone,periodontal tissue defects,skin repairs,and corneal transplantation.Recently,tremendous advances have been made in TE regarding neuroscience.In this review,we summarize TE’s recent progress in neuroscience,including pathological mechanisms of various neurological disorders,the concepts and classification of TE,and the most recent development of TE in neuroscience.Lastly,we prospect the future directions and unresolved problems of TE in neuroscience. 展开更多
关键词 ORGANS DIRECTIONS REPAIR
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Correction: Optimizing Exciton and Charge-Carrier Behavior in Thick-Film Organic Photovoltaics: A Comprehensive Review
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作者 Lu Wei Yaxin Yang +2 位作者 Lingling Zhan Shouchun Yin Hongzheng Chen 《Nano-Micro Letters》 2026年第1期608-608,共1页
Correction to:Nano-Micro Letters(2026)18:10.https://doi.org/10.1007/s40820-025-01852-8 Following publication of the original article[1],the authors reported that the last author’s name was inadvertently misspelled.Th... Correction to:Nano-Micro Letters(2026)18:10.https://doi.org/10.1007/s40820-025-01852-8 Following publication of the original article[1],the authors reported that the last author’s name was inadvertently misspelled.The published version showed“Hongzhen Chen”,whereas the correct spelling should be“Hongzheng Chen”.The correct author name has been provided in this Correction,and the original article[1]has been corrected. 展开更多
关键词 charge carrier behavior exciton behavior comprehensive review thick film organic photovoltaics nano micro letters
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Optimizing Exciton and Charge-Carrier Behavior in Thick-Film Organic Photovoltaics:A Comprehensive Review
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作者 Lu Wei Yaxin Yang +2 位作者 Lingling Zhan Shouchun Yin Hongzheng Chen 《Nano-Micro Letters》 2026年第1期229-267,共39页
Organic photovoltaics(OPVs)have achieved remarkable progress,with laboratory-scale single-junction devices now demonstrating power conversion efficiencies(PCEs)exceeding 20%.However,these efficiencies are highly depen... Organic photovoltaics(OPVs)have achieved remarkable progress,with laboratory-scale single-junction devices now demonstrating power conversion efficiencies(PCEs)exceeding 20%.However,these efficiencies are highly dependent on the thickness of the photoactive layer,which is typically around 100 nm.This sensitivity poses a challenge for industrial-scale fabrication.Achieving high PCEs in thick-film OPVs is therefore essential.This review systematically examines recent advancements in thick-film OPVs,focusing on the fundamental mechanisms that lead to efficiency loss and strategies to enhance performance.We provide a comprehensive analysis spanning the complete photovoltaic process chain:from initial exciton generation and diffusion dynamics,through dissociation mechanisms,to subsequent charge-carrier transport,balance optimization,and final collection efficiency.Particular emphasis is placed on cutting-edge solutions in molecular engineering and device architecture optimization.By synthesizing these interdisciplinary approaches and investigating the potential contributions in stability,cost,and machine learning aspects,this work establishes comprehensive guidelines for designing high-performance OPVs devices with minimal thickness dependence,ultimately aiming to bridge the gap between laboratory achievements and industrial manufacturing requirements. 展开更多
关键词 Organic photovoltaics THICK-FILM EXCITON Charge-carrier Photovoltaic performances
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A Phenol-containing α-Diimine Ligand for Nickel-and Palladium-Catalyzed Ethylene Polymerization 被引量:12
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作者 Chen Tan Wen-Min Pang Chang-Le Chen 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2019年第10期974-980,I0003,共8页
A phenol-containing dibenzhydryl-based α-diimine ligand bearing hydroxy group on para-position of aniline moiety was designed, synthesized, and investigated in Ni-and Pd-catalyzed ethylene polymerization. The Ni comp... A phenol-containing dibenzhydryl-based α-diimine ligand bearing hydroxy group on para-position of aniline moiety was designed, synthesized, and investigated in Ni-and Pd-catalyzed ethylene polymerization. The Ni complex bearing hydroxy groups resulted in not only high polyethylene molecular weight(Mn up to 1.5 × 10^~6), but also significantly increased melting temperature(Tm up to 123℃) and greatly decreased branching density(33/1000 C) versus the Ni catalyst bearing OMe group on para-position of aniline moiety. This is consistent with the hypothesis that the deprotonation of the phenol moiety generated a phenoxide bearing strong electrondonating O-substituent by methylaluminoxane(MAO) cocatalyst. The Pd complexes bearing hydroxy groups exhibited similar catalytic properties to those of the Pd catalyst bearing OMe groups did. 展开更多
关键词 Α-DIIMINE Ethylene polymerization Electronic effect PALLADIUM NICKEL
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Synthesis and Characterization of Trans-1,4-butadiene/Isoprene Copolymers: Determination of Sequence Distribution and Thermal Properties 被引量:11
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作者 Xiu-bo Jiang Qing-fei Zhang 贺爱华 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2015年第6期815-822,共8页
Abstract Two series of trans-1,4-poly(butadiene-co-isoprene) copolymers (TBIR) were prepared using the catalyst system TiCl4/MgCl2-Al(i-Bu)3 at different reaction temperatures. All dyad and triads sequence distr... Abstract Two series of trans-1,4-poly(butadiene-co-isoprene) copolymers (TBIR) were prepared using the catalyst system TiCl4/MgCl2-Al(i-Bu)3 at different reaction temperatures. All dyad and triads sequence distributions, the number-average sequence length and the sequence concentration of the copolymers were calculated according to 13C-NMR spectra. The influences of temperature and initial molar ratio of butadiene to isoprene (Bd to Ip) on the distribution of the chain segments in the TBIR copolymers were discussed. The correlation of copolymer compositions and thermal properties were also evaluated, which facilitated the understanding of controlling the degree of crystallinity and the transition tempera^re by changing Bd content and temperature. 展开更多
关键词 Trans-1 4- ISOPRENE BUTADIENE COPOLYMER Thermal properties.
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HYDROPHILIC NANOFILTRATION MEMBRANES WITH SELF-POLYMERIZED AND STRONGLY-ADHERED POLYDOPAMINE AS SEPARATING LAYER 被引量:12
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作者 朱利平 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2012年第2期152-163,共12页
Inspired by the self-polymerization and strong adhesion characteristics of dopamine in aqueous conditions, a novel hydrophilic nanofiltration (NF) membrane was fabricated by simply dipping polysulfone (PSf) ultraf... Inspired by the self-polymerization and strong adhesion characteristics of dopamine in aqueous conditions, a novel hydrophilic nanofiltration (NF) membrane was fabricated by simply dipping polysulfone (PSf) ultrafiltration (UF) substrate in dopamine solution. The changes in surface chemical composition and morphology of membranes were determined by Fourier transform infrared spectroscopy (FTIR-ATR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and atomic force microscopy (AFM). The experimental results indicated that the self-polymerized dopamine formed an ultrathin and defect-free barrier layer on the PSf UF membrane. The surface hydrophilicity of membranes was evaluated through water contact angle measurements. It was found that membrane hydrophilicity was significantly improved after coating a polydopamine (pDA) layer, especially after double coating. The dyes filtration experiments showed that the double-coated membranes were able to reject completely the dyes of brilliant blue, congo red and methyl orange with a pure water flux of 83.7 L/(mE.h) under 0.6 MPa. The zeta potential determination revealed the positively-charged characteristics of PSf/pDA composite membrane in NF process. The salt rejection of the membranes was characterized by 0.01 mmol/L of salts filtration experiment. It was demonstrated that the salts rejections followed the sequence: NaC1 〈 NaaSO4 〈 MgSO4 〈 MgC12 〈 CaCl2, and the rejection to CaC12 reached 68.7%. Moreover, the composite NF membranes showed a good stability in water-phase filtration process. 展开更多
关键词 DOPAMINE SELF-POLYMERIZATION Strong adhesion Nanofiltration membrane.
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Synthesis and Characterization of trans-1,4-Butadiene/Isoprene Copolymers: Determination of Monomer Reactivity Ratios and Temperature Dependence 被引量:9
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作者 Qing-fei Zhang Xiu-bo Jiang 贺爱华 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2014年第8期1068-1076,共9页
A series of trans-1,4-butadiene/isoprene copolymers were prepared using the catalyst system TiCl4/MgCl2-Al(i- Bu)3 with bulk precipitation technology at different temperatures. Monomers reactivity ratios were calcul... A series of trans-1,4-butadiene/isoprene copolymers were prepared using the catalyst system TiCl4/MgCl2-Al(i- Bu)3 with bulk precipitation technology at different temperatures. Monomers reactivity ratios were calculated based on the Kelen-Tiid6s (K-T) method and the Mao-Huglin (M-H) method. The influence of temperature on copolymer composition and polymerization rate was discussed in detail. The increase of reaction temperature brought the decrease of butadiene reactivity ratio rBd and supplied an effective adjustment on copolymers' composition distribution. 展开更多
关键词 trans-1 4- ISOPRENE BUTADIENE COPOLYMER Reactivity ratio.
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Improving Damping Properties and Thermal Stability of Epoxy/Polyurethane Grafted Copolymer by Adding Glycidyl POSS 被引量:8
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作者 Ge-Liang Zhu Di Han +2 位作者 Ye Yuan Feng Chen Qiang Fu 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2018年第11期1297-1302,共6页
Modified castor oil-based epoxy resin (EP)/polyurethane (PU) grafted copolymer by glycidyl polyhedral oligomeric silsesquioxane (glycidyl POSS) was synthesized. The damping properties, thermal stability, mechani... Modified castor oil-based epoxy resin (EP)/polyurethane (PU) grafted copolymer by glycidyl polyhedral oligomeric silsesquioxane (glycidyl POSS) was synthesized. The damping properties, thermal stability, mechanical properties and morphology of the grafted copolymer modified by glycidyl POSS were studied systematically. The results revealed that the incorporation of glycidyl POSS improved the damping performance evidently and broadened damping temperature range, especially when the glycidyl POSS content was 0.2%-1%. At the same time, there was a slight increase in thermal stability with the increase of POSS content. The tensile properties changed with the change of the copolymer's Tg, decreased at low POSS contents and increased at high POSS contents. This modified copolymer has the potential to be used as film damping material or constrained damping layer. 展开更多
关键词 EPOXY POLYURETHANE POSS DAMPING Thermal stability
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INFLUENCE OF SILOXANE CO-SEGMENT LENGTH AND CONTENT OF WATERBORNE POLYSILOXANE-URETHANE COPOLYMERS ON THEIR WATER RESISTANCE,THERMAL STABILITY AND MECHANICAL PROPERTIES 被引量:7
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作者 郑强 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2010年第2期219-229,共11页
A series of stable waterborne polysiloxaneurethane (WPSUR) dispersions were prepared using amino-terminated polydimethylsiloxane (NS), dimethylolpropionic acid (DMPA), castor oil, polypropylene glycol and toluen... A series of stable waterborne polysiloxaneurethane (WPSUR) dispersions were prepared using amino-terminated polydimethylsiloxane (NS), dimethylolpropionic acid (DMPA), castor oil, polypropylene glycol and toluene diisocyanate. Meanwhile, NS with different molecular weights was synthesized and used as the soft co-segment. Effects of types and contents of soft co-segments as well as chain extenders on the thermal degradation and stability for WPSUR films were examined. Results reveal that WPSUR films exhibit excellent water resistance and mechanical properties as compared with pure polyurethane (PU) films, and the NS soft co-segment possesses a remarkable effect on the second stage (stage Ⅱ), while the content of the hard segment is propitious to the initial stage (stage Ⅰ). Moreover, the highest temperature of stage Ⅱ (T2m) for WPSUR films using NS as soft co-segment is 413℃, approximately being 30℃ higher than that of those typical PUs using HDA and APDMS as the chain extenders, respectively. 展开更多
关键词 WATERBORNE POLYSILOXANE POLYURETHANE Castor oil Thermal properties Water resistance.
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Ligand Steric Effects on Naphthyl-α-diimine Nickel Catalyzed α-Olefin Polymerization 被引量:11
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作者 Fu-Zhou Wang Su-Su Tian +2 位作者 Rui-Ping Li Wei-Min Li Chang-Le Chen 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2018年第2期157-162,共6页
Naphthyl-α-diimine nickel complexes with systematically varied ligand sterics, activated by modified methylaluminoxane(MMAO), were tested in the polymerization of higher α-olefin(1-hexene, 1-decene and 1-hexadec... Naphthyl-α-diimine nickel complexes with systematically varied ligand sterics, activated by modified methylaluminoxane(MMAO), were tested in the polymerization of higher α-olefin(1-hexene, 1-decene and 1-hexadecene) under suitable conditions. The polymerization results indicated the possibility of precise microstructure control, depending on catalyst structure, polymerization temperature, monomer concentration and types of monomers, which in turn strongly affects the resultant polymer properties. Naphthyl-α-diimine nickel complex bearing chiral bulky sec-phenethyl groups in the o-naphthyl position showed good catalytic activity, and resulted in branched polymers(42-88/1000 C) with high molecular weights(Mn:(4.3-15.2) × 10^4 g·mol^-1) and narrow molecular weight distribution(Mw/Mn = 1.13-1.29, RT), which suggested a living polymerization. The increasing steric hindrance of catalyst leads to enhance insertion for 2,1-insertion of α-olefin and the chain-walking reaction. 展开更多
关键词 Naphthyl-α-diimine nickel complex Chain-walking polymerization Higher α-olefin Steric effect
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THE DEGRADATION AND BIOCOMPATIBILITY OF WATERBORNE BIODEGRADABLE POLYURETHANES FOR TISSUE ENGINEERING 被引量:8
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作者 Ni-jia Song Xia Jiang +4 位作者 Jie-hua Li Yong Pang Jian-shu Li Hong Tan Qiang Fu 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2013年第10期1451-1462,共12页
To better investigate the degradation and biocompatibility of waterborne biodegradable polyurethanes for tissue engineering, a series of new waterborne biodegradable polyurethanes (PEGPUs) with low degree of crossli... To better investigate the degradation and biocompatibility of waterborne biodegradable polyurethanes for tissue engineering, a series of new waterborne biodegradable polyurethanes (PEGPUs) with low degree of crosslinking was synthesized using IPDI, BDO and L-lysine as hard segments, PCL and PEG as soft segment. The bulk structures and properties of the prepared polyurethanes were characterized by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), tensile mechanical tests and water contact angle (WCA) measurements. The degree of microphase separation was slightly improved because of the lowered crosslinking degree of these PEGPUs in comparison with the high cross-linking degree samples, leading to good mechanical properties, as indicated by DSC and stress-strain data. Moreover, biodegradability of the polyurethanes was evaluated in phosphate buffer solutions (PBS) under different pH values and enzymatic solution at pH 7.4 through weight loss monitoring. The results suggested that the degradation of these PEGPUs was closely related to their bulk and surface properties. And the degradation products didn't show apparent inhibition effect against fibroblasts in vitro. These studies demonstrated that the waterborne biodegradable polyurethanes could find potential use in soft tissue engineering and tissue regeneration. 展开更多
关键词 Waterborne biodegradable polyurethane STRUCTURE DEGRADATION Cytotoxicity.
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DRUG AND PLASMID DNA CO-DELIVERY NANOCARRIERS BASED ON ABC-TYPE POLYPEPTIDE HYBRID MIKTOARM STAR COPOLYMERS 被引量:6
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作者 Tao Liu Yan-feng Zhang 刘世勇 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2013年第6期924-937,共14页
We report on the fabrication of self-assembled micelles from ABC-type miktoarm star polypeptide hybrid copolymers consisting of poly(ethylene oxide), poly(L-lysine), and poly(e-caprolactone) arms, PEO(-b-PLL)-... We report on the fabrication of self-assembled micelles from ABC-type miktoarm star polypeptide hybrid copolymers consisting of poly(ethylene oxide), poly(L-lysine), and poly(e-caprolactone) arms, PEO(-b-PLL)-b-PCL, and their functional applications as co-delivery nanocarriers of chemotherapeutic drugs and plasmid DNA. Miktoarm star copolymer precursors, PEO(-b-PZLL)-b-PCL, were synthesized at first via the combination of consecutive "click" reactions and ring-opening polymerizations (ROP), where PZLL is poly(e-benzyloxycarbonyl-L-lysine). Subsequently, the deprotection of PZLL arm afforded amphiphilic miktoarm star copolymers, PEO(-b-PLL)-b-PCL. In aqueous media at pH 7.4, PEO(-b-PLL)-b-PCL self-assembles into micelles consisting of PCL cores and hydrophilic PEO/PLL hybrid coronas. The hydrophobic micellar cores can effectively encapsulate model hydrophobic anticancer drug, paclitaxel; whereas positively charged PLL arms within mixed micellar corona are capable of forming electrostatic polyplexes with negatively charged plasmid DNA (pDNA) at N/P ratios higher than ca. 2. Thus, PEO(-b-PLL)-b-PCL micelles can act as co-delivery nanovehicles for both chemotherapeutic drugs and genes. Furthermore, polyplexes of pDNA with paclitaxel-loaded PEO(-b- PLL)-b-PCL micelles exhibited improved transfection efficiency compared to that of pDNA/blank micelles. We expect that the reported strategy of varying chain topologies for the fabrication of co-delivery polymeric nanocarriers can be further applied to integrate with other advantageous functions such as targeting, imaging, and diagnostics. 展开更多
关键词 Miktoarm star copolymers Gene delivery CO-DELIVERY POLYPEPTIDE SELF-ASSEMBLY
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