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Highly efficient room temperature phosphorescent liquid crystalline polymer optical waveguides for advanced optoelectronics

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Science China Chemistry 2024年

作者： Jie Li Yan Guan Wei Xia Jin-Kang chen Jiang Huang Yi chen Qi Lin er-qiang chen He-Lou Xie Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of Education and Key Laboratory of Advanced Functional Polymer Materials of CollegesUniversities of Hunan Province and College of ChemistryXiangtan University Beijing National Laboratory for Molecular Sciences Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking University School of Physics and Optoelectronics Xiangtan University

Active organic optical waveguide materials (OOWMs) incorporating room temperature phosphorescence (RTP) hold significant promise for diverse applications in photonic and optoelectronic devices.Despite this potential,realizing active RTP optical waveguides with large-sized ordered structures and minimal light loss remains a formidable challenge.To address this issue,we present a groundbreaking thermoplastic active OOWM with low light loss,leveraging room temperature phosphorescent liquid crystalline polymer (LCP).This innovative material can be easily synthesized through the copolymerization of phosphorescent and liquid crystalline monomers.The resulting RTP copolymer exhibits a nematic liquid crystal phase with a phosphorescence lifetime of approximately 0.15 ms and an afterglow duration of around 1 second.Leveraging the excellent processability of LCP,we successfully produce meter-scale fibers via melt spinning.These RTP LCP fibers,characterized by a high orientation of mesogens along the fiber axis,demonstrate superior light confinement and efficient light conduction compared to unoriented samples,resulting in a low optical loss coefficient of 0.13 dB/mm.Furthermore,the thermal responsiveness of the RTP LCP optical waveguide enables its use as a photo switch.This pioneering work paves the way for the design of new OOWMs tailored for advanced photonics and optoelectronics devices.

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Structure-Property Relationship Analysis of D-Penicillamine-Derivedβ-Polythioesters with Varied Alkyl Side Groups

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高分子科学:英文版 2023年第10期41卷 1555-1562页

作者： Chun-Yan Lyu Wei Xiong er-qiang chen Hua Lu Beijing National Laboratory for Molecular Sciences Center for Soft Matter Science and EngineeringKey Laboratory of Polymer Chemistry and Physics of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing100871China

The ring-opening polymerization of heterocyclic monomers and the reversed ring-closing depolymerization of corresponding polymers with neutral thermodynamics are broadly explored to establish a circular economy of next-generation plastics.Polythioesters(PTEs),analogues of polyesters,are emerging materials for this purpose due to their high refractive index,high crystallinity,dynamic property and responsiveness.In this work,we synthesize and polymerize a series of D-penicillamine-derivedβ-thiolactones(NRPenTL)with varied side chain alkyl groups,and study the structure-property relationship of the resulting polymers.The obtained PTEs exhibit tunable glass transition temperature in a wide range of 130–50℃,and melting temperature of 90–105℃.In addition,copolymerizations of monomers with different side chains are effective in modulating material properties.The obtained homo and copolymers can be fully depolymerized to recycle monomers.This work provides a robust molecular platform and detailed structure-property relationship of PTEs with potential of achieving sustainable plastics.

关键词： β-Polythioesters Geminal dimethyl Structure-property relationship Chemical recycling to monomers

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The Shackling Effect in Cyclic Azobenzene Liquid Crystal

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Chinese Journal of Polymer Science 2022年第6期40卷 584-592页

作者： Yang Xiao Chong He Zi-Fan Yang er-qiang chen Huan-Jun Lu Xiao-Hong Li Ying-Feng Tu State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials College of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China Beijing National Laboratory for Molecular Sciences Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCenter for Soft Matter Science and EngineeringCollege of ChemistryPeking UniversityBeijing 100871China Jiangsu Key Laboratory of Micro and Nano Heat Fluid Flow Technology and Energy Application School of Physical Science and TechnologySuzhou University of Science and TechnologySuzhou 215009China

We demonstrate here a novel method for the design of liquid crystals(LCs)via the cyclization of mesogens by flexible chains.For two azobenzene-4,4′-dicarboxylate derivatives,the cyclic dimer,cyclic bis(tetraethylene glycol azobenzene-4,4′-dicarboxylate)(CBTAD),shows LC properties with smectic A phase,while its linear counterpart,bis(2-(2′-hydroxyethyloxy))ethyl azobenzene-4,4′-dicarboxylate(BHAD),has no LC phase.The difference is ascribed to the shackling effect from the cyclic topology,which leads to the much smaller entropy change during phase transitions and increases the isotropic temperature greatly for cyclics.In addition,the trans-to-cis isomerization of azobenzene groups under UVlight is also limited in CBTAD.With the reversible isomerization of azobenzene groups,CBTAD showed interesting isothermal phase transition behaviors,where the LC phase disappeared upon photoirradiation of 365 nm UV-light,and recovered when the UV-light was off.Combined with the smectic LC nature,a novel UV-light tuned visible light regulator was designed,by simply placing CBTAD in two glass plates.The scattered phase of smectic LC was utilized as the“OFF”state for light passage,while the UV-light induced isotropic phase was utilized as the“ON”state.The shackling effect outlined here should be applicable for the design of cyclic LC oligomers/polymers with special properties.

关键词： Azobenzene Cyclic Liquid crystals Isothermal phase transition

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Competition of Lamellar Crystal and Smectic Liquid Crystal in Precise Polyethylene Derivative Bearing Mesogenic Side-Chains

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CCS Chemistry 2022年第2期4卷 683-692页

作者： Wen-Ying Chang Yan-Fang Zhang Jing Wang Dong Shi Xu-qiang Jiang Xiang-Kui Ren Shuang Yang er-qiang chen Beijing National Laboratory for Molecular Sciences Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCenter for Soft Matter Science and EngineeringCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871 South China Advanced Institute for Soft Matter Science South China University of TechnologyGuangzhou 510640 School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350

For side-chain liquid-crystalline polymers(SCLCPs)bearing calamitic mesogens,nematic and typical smectic(Sm)phases are expected.Here,using a precise polyethylene derivative with the biphenyl moiety tethered on every ninth carbon(P9,b),we demonstrated that an SCLCP could form a crystal(Cr)phase in addition to an Sm phase.Two opposing interrelations of main-and side-chains determined the molecular packings.While the side-chain inclined to be perpendicular to the main-chain in the Sm phase,they paralleled and coassembled in the Cr phase with an orthorhombic structure.The Sm phase of P9,b was new in SCLCPs.Within the mesogen sublayers,the biphenyls were tilted and had a type of two-dimensional positional order,making this Sm phase ordering higher than that of smectic C.The Sm phase was metastable and kinetically grew faster below its isotropic temperature.However,it could not convert to the stable Cr phase unless it transitioned into the melting state.Fantastically,P9,b rendered the lamellar crystal in the Cr phase.The lenticular lamellae resembled that found in linear polyethylene crystallized at low undercooling.Importantly,albeit having the large anisotropic pendants situated regularly in the backbone,P9,b could follow the principle of chain-folding crystallization.

关键词： precision polymer side-chain liquid-crystalline polymer polyethylene derivative self-assembly liquid crystal crystallization chain-folding lamella

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4-Hydroxy-L-Proline as a General Platform for Stereoregular Aliphatic Polyesters:Controlled Ring-Opening Polymerization,Facile Functionalization,and Site-Specific Bioconjugation

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CCS Chemistry 2020年第5期2卷 236-244页

作者： Jingsong Yuan Dong Shi Yi Zhang Jianhua Lu Letian Wang er-qiang chen Hua Lu Beijing National Laboratory for Molecular Sciences Center for Soft Matter Science and EngineeringKey Laboratory of Polymer Chemistry and Physics of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871(China)

Degradable polyesters have long been regarded as eco-friendly materials,useful for various applicationswhile meeting the growing needs of sustainability.However,it is still challenging to synthesize functional aliphatic polyesters from abundant and cheap renewable sources.Our present study reports a readily available and versatile platform for producing functional and stereoregular aliphatic polyesters from 4-hydroxy-L-proline(4-HYP).We synthesized a bicyclic bridged lactone monomer,namely,NR-PL,by a simple and scalable two-step process allowing facile side-chain functionalization and derivatization.The ring-opening homopolymerization and copolymerization for the generation of N^(R)-PL were controlled fully by using organobases such as 1,8-diazabicyclo[5.4.0]-undec-7-ene(DBU)without any detectable epimerization.This process afforded stereoregular polyesters PNRPE with molar mass(M_(n))up to 90 kg/mol and a narrow dispersity(Ð)generally below 1.10.The uniqueness of the backbone,which contains two chiral centers on a rigid propyl ring,together with the versatility of the side chain,offer tunable properties complementary to existing aliphatic polyesters.The utility of the polymers was showcased by the facile site-specific bioconjugation of PN^(EG3)PE,a water-soluble polyester,to a protein.This work might open numerous opportunities in creating functional and sustainable polyesters for a wide range of applications,including degradable plastics,drug delivery,and protein therapeutics.

关键词： 4-hydroxyproline ROP sustainable polyester stereoregular bioconjugation

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Hemiphasmid Side-Chain Liquid Crystalline Polynorbornene: Phase Structure and Strain-Hardening Based on “Multi-Chain Column” Physical Crosslinks

Hemiphasmid Side-Chain Liquid Crystalline Polynorbornene: Ph...

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2016年两岸三地高分子液晶态与超分子有序结构学术研讨...

作者： Ruiying Zhao Shuang Yang er-qiang chen Beijing National Laboratory for Molecular Sciences Department of Polymer Science and Engineering and Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCollege of Chemistry and Molecular Engineering Peking University

＜正＞Hemiphasmid mesogen is composed of two parts with different shapes,a rod-like and a fan-like moieties that are linked together.1 Due to the special shape matching mechanism,side-chain liquid crystalline polymers（SCLCPs）with side groups containing hemiphasmid mesogens have fantastic ability of self-assembly.The diversity of side groups provides abundant manners for designing ordered

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Development and validation of a nomogram to predict allograft survival after pediatric liver transplantation

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World Journal of Pediatrics 2024年第3期20卷 239-249页

作者： Guang-Xiang Gu Shu-Ting Pan Yi-chen Fan chen chen qiang Xia Department of Liver Surgery Renji HospitalShanghai Jiaotong University School of MedicineNo.160 Pujian RoadPudong New DistrictShanghai 200128China Department of Liver Transplantation Sun Yet-Sen Memorial HospitalSun Yat-Sen UniversityNo.107 Yanjiang West RoadGuangzhou 510080China Clinical Center for Investigation Renji HospitalShanghai Jiaotong University School of MedicineShanghaiChina Department of Anesthesiology Renji HospitalShanghai Jiaotong University School of MedicineShanghaiChina

Background Liver transplantation is the main treatment for cholestatic liver disease and some metabolic liver diseases in children.However,no accurate prediction model to determine the survival probability of grafts prior to surgery exists.This study aimed to develop an effective prognostic model for allograft survival after pediatric liver transplantation.Methods This retrospective cohort study included 2032 patients who underwent pediatric liver transplantation between January 1,2006,and January 1,2020.A nomogram was developed using Cox regression and validated based on bootstrap sampling.Predictive and discriminatory accuracies were determined using the concordance index and visualized using calibration curves;net benefits were calculated for model comparison.An online Shiny application was developed for easy access to the model.Results Multivariable analysis demonstrated that preoperative diagnosis,recipient age,body weight,graft type,preoperative total bilirubin,interleukin-1β,portal venous blood flow direction,spleen thickness,and the presence of heart disease and cholangitis were independent factors for survival,all of which were selected in the nomogram.Calibration of the nomogram indicated that the 1-,3-,and 5-year predicted survival rates agreed with the actual survival rate.The concordance indices for graft survival at 1,3,and 5 years were 0.776,0.757,and 0.753,respectively,which were significantly higher than those of the Pediatric End-Stage Liver Disease and Child-Pugh scoring systems.The allograft dysfunction risk of a recipient could be easily predicted using the following URL:https://aspelt.***.io/ASPELT/l Conclusion The allograft survival after pediatric liver transplantation(ASPELT)score model can effectively predict the graft survival rate after liver transplantation in children,providing a simple and convenient evaluation method for clinicians and patients.

关键词： Allograft survival Nomogram Pediatric liver transplantation

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Fe-N_(x) sites coupled with core-shell FeS@C nanoparticles to boost the oxygen catalysis for rechargeable Zn-air batteries

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Journal of Energy Chemistry 2024年第3期90卷 565-577,I0013页

作者： Katam Srinivas Zhuo chen Anran chen Fei Ma Ming-qiang Zhu Yuanfu chen School of Integrated Circuit Science and Engineering and State Key Laboratory of Electronic Thin Films and Integrated DevicesUniversity of Electronic Science and Technology of ChinaChengdu 610054SichuanChina College of Mechanical and Electronic Engineering Northwest A&F UniversityYangling 712100ShaanxiChina School of Materials and Energy Yunnan UniversityKunming 650091YunnanChina

The development of efficient single-atom catalysts(SACs) for the oxygen reduction reaction(ORR)remains a formidable challenge,primarily due to the symmetric charge distribution of metal singleatom sites(M-N_(4)).To address such issue,herein,Fe-N_(x) sites coupled synergistic catalysts fabrication strategy is presented to break the uniform electronic distribution,thus enhancing the intrinsic catalytic activity.Precisely,atomically dispersed Fe-N_(x) sites supported on N/S-doped mesoporous carbon(NSC)coupled with FeS@C core-shell nanoparticles(FAS-NSC@950) is synthesized by a facile hydrothermal reaction and subsequent pyrolysis.Due to the presence of an in situ-grown conductive graphitic layer(shell),the FeS nanoparticles(core) effectively adjust the electronic structure of single-atom Fe sites and facilitate the ORR kinetics via short/long-range coupling interactions.Consequently,FAS-NSC@950displays a more positive half-wave potential(E_(1/2)) of 0.871 V with a significantly boosted ORR kinetics(Tafel slope=52.2 mV dec^(-1)),outpacing the commercial Pt/C(E_(1/2)=0.84 V and Tafel slope=54.6 mV dec^(-1)).As a bifunctional electrocatalyst,it displays a smaller bifunctional activity parameter(ΔE) of 0.673 V,surpassing the Pt/C-RuO_(2) combination(ΔE=0.724 V).Besides,the FAS-NSC@950-based zincair battery(ZAB) displays superior power density,specific capacity,and long-term cycling performance to the Pt/C-Ir/C-based ZAB.This work significantly contributes to the field by offering a promising strategy to enhance the catalytic activity of SACs for ORR,with potential implications for energy conversion and storage technologies.

关键词： Fe-N_(x)sites Core-shell FeS@C Synergistic interactions Oxygen reduction reaction Zn-air battery

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Charge transfer complex enabled photoreduction of ether phosphonium salts for the selective oxyalkylation of enamides

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Chinese Chemical Letters 2024年第2期35卷 411-414页

作者： Sen Qiao Kunquan chen qiang Liu Zhixiang Wang Xiangyu chen School of Chemical Sciences University of the Chinese Academy of SciencesBeijing 100049China Binzhou Institute of Technology Weiqiao-UCAS Science and Technology ParkBinzhou 256606China

A charge transfer complex(CTC)-enabled photoreduction of ether phosphonium salts for the generation of oxyalkyl radicals was described.The photoreduction provides a convenient method to achieve selective oxyalkylation of enamides with broad substrate scope.The method features operational simplicity,mild and inherent green conditions.

关键词： Enamides Phosphonium salts Ethers Charge transfer complex Visible light

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Transient receptor potential vanilloid 1 involved in the analgesic effects of total flavonoids extracted from Longxuejie(Resina Dracaenae Cochinchinensis)

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Journal of Traditional Chinese Medicine 2024年第3期44卷 437-447页

作者： MO Xiaoqiang chen Yating YIN Qian chen Haibo BAN qiang LI Jun chen Su YAO Jinguang Department of Stomatology Affiliated Hospital of Youjiang Medical University for Nationalities College of General Practitioners Youjiang Medical University for Nationalities College of Biomedical Engineering South-Central Minzu UniversityKey Laboratory of Cognitive Science of State Ethnic Affairs CommissionHubei Key Laboratory of Medical Information Analysis and Tumor Diagnosis and Treatment College of Pharmacy South-Central Minzu University

OBJECTIVE: To evaluate the analgesic effects of total flavonoids of Longxuejie(Resina Dracaenae Cochinchinensis)(TFDB) and explore the possible analgesic mechanism associated with transient receptor potential vanilloid 1(TRPV1).METHODS: Whole-cell patch clamp technique was used to observe the effects of TFDB on capsaicin-induced TRPV1 currents. Rat experiments in vivo were used to observe the analgesic effects of TFDB. Western blot and immunofluorescence experiments were used to test the change of TRPV1 expression in DRG neurons induced by TFDB.RESULTS: Results showed that TFDB inhibited capsaicin-induced TRPV1 receptor currents in acutely isolated dorsal root ganglion(DRG) neurons of rats and the half inhibitory concentration was(16.7 ± 1.6) mg/L.TFDB(2-20 mg/kg) showed analgesic activity in the phase Ⅱ of formalin test and(0.02-2 mg per paw)reduced capsaicin-induced licking times of rats. TFDB(20 mg/kg) was fully efficacious on complete Freund's adjuvant(CFA)-induced inflammatory thermal hyperalgesia and capsaicin could weaken the analgesic effects. The level of TRPV1 expressions of DRG neurons was also decreased in TFDB-treated CFA-inflammatory pain rats.CONCLUSION: All these results indicated that the analgesic effect of TFDB may contribute to their modulations on both function and expression of TRPV1 channels in DRG neurons.

关键词： Freund's adjuvant Longxuejie () capsaicin flavonoids formaldehyde inflammatory pain transient receptor potential vanilloid 1

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