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Chinese Journal of Polymer Science 2022年第1期40卷 21-28页

作者： Dong Liu fan Wu Zhi-Hao Shen xing-he fan 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 100871China

Liquid electrolytes used in lithium-ion batteries suffer from leakage,flammability,and lithium dendrites,making polymer electrolyte a potential ***,a series of ABA triblock copolymers(ABA-x)containing a mesogen-jacketed liquid crystalline polymer(MJLCP)with a polynorbornene backbone as segment A and a second polynorbornene-based polymer having poly(ethylene oxide)(PEO)side chains as segment B were synthesized through tandem ring-opening metathesis *** block copolymers can self-assemble into ordered morphologies at 200℃.After doping of lithium salts and ionic liquid(IL),ABA-x self-assembles into cylindrical *** MJLCP segments with a high glass transition temperature and a stable liquid crystalline phase serve as physical crosslinking points,which significantly improve the mechanical performance of the polymer *** ionic conductivity of ABA-x/lithium salt/IL is as high as 10-3 S·cm-1 at ambient temperature owing to the high IL uptake and the continuous phase of conducting PEO *** relationship between ionic conductivity and temperature fits the Vogel-Tamman-Fulcher(VTF)*** addition,the electrolyte films are flame retardant owing to the addition of *** polymer electrolytes with good safety and high ambient-temperature ionic conductivity developed in this work are potentially useful in solid lithium-ion batteries.

关键词： ABA triblock copolymer Polymer electrolyte Ionic conductivity Inflammability Cylindrical structure

Self-assembly and Properties of Block Copolymers Containing MesogenJacketed Liquid Crystalline Polymers as Rod Blocks

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Chinese Journal of Polymer Science 2018年第7期36卷 811-821页

作者： Xiao-Lin Lyu Hong-Bing Pan Zhi-Hao Shen xing-he fan Beijing National Laboratory for Molecular Sciences Key Laboratory of Polymer Chemistry and Physics of Ministry of Education Center for Soft Matter Science and Engineering College of Chemistry and Molecular Engineering Peking University

Mesogen-jacketed liquid crystalline polymer （MJLCP） has attracted great attention because of its rigid conformation, facile synthesis, and structural controllability. In this feature article, the self-assembly of MJLCP-based block copolymers （BCPs） is briefly reviewed, especially the nanostructures of rod-coil diblock copolymers （diBCPs）, rod-rod diBCPs, and triblock copolymers. In addition, the properties of the self-assembled BCPs are also summarized, including their applications as liquid crystalline thermoplastic elastomers and solid polymer electrolytes. The article also discusses the major challenges and future directions in the study of MJLCP-based BCPs.

关键词： Mesogen-jacketed liquid crystalline polymer Block copolymer Rod block Self-assembly Properties

CRYSTAL ORIENTATION AND MELTING BEHAVIOR OF POLY(ε-CAPROLACTONE) UNDER ONE-DIMENSIONALLY “HARD” CONFINED MICROENVIRONMENT

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Chinese Journal of Polymer Science 2013年第6期31卷 946-958页

作者： Xuan-bo Liu Yong-feng Zhao xing-he fan 陈尔强 Beijing National Laboratory for Molecular Sciences Department of Polymer Science and Engineering and Key Laboratory of Polymer Chemistry and Physics of Ministry of Education College of Chemistry and Molecular Engineering Peking University Research Institute of Material Science Beijing Research Institute of Chemical Industry SINOPEC

Crystal orientation and melting behavior of poly（e-caprolactone） in a diblock copolymer of poly（e-caprolactone）- block-poly（2,5-bis[4-methoxyphenyl]oxycarbonyl）styrene）（PCL-b-PMPCS） was investigated. The degrees of polymerization of the PCL and PMPCS block are 200 and 98, respectively. With the PMPCS in a columnar liquid crystalline phase, the diblock is rod-coil one, which exhibits a lamellar phase morphology with the PCL layer thickness of 15.2 nm. Since the glass transition temperature of PMPCS block is much higher than the melting temperature of PCL, the crystallization of PCL is in a one-dimensionally ＂hard＂ confinement environment. Mainly on the basis of two-dimensional wide-angle X-ray diffraction experiments, we identified the orientation of PCL isothermally crystallized at various crystallization temperatures （Tos）. At high Tcs （To 〉 10 ℃）, the c-axis of the PCL crystal is along the layer normal of the microphase-separated sturcture. Decreasing Tc can result in the tilting of PCL c-axis with respect to the layer normal. The lower the Tc is, the more the c-axis inclines. Meanwhile, the b-axis of PCL remains perpendicular to the layer normal. At a very low Tc of-78 ℃, the orientation of the PCL crystals is completely random. For the samples isothermally crystallized at Tc 〈 10 ℃, double melting behavior can be observed. While the low temperature endotherm reflects the melting of the crystals originally formed at the Tc applied, the high temperature one is associated with the crystals subjected to the process of recrystallization/reorganization upon heating due to the annealing effect.

关键词： Crystallization Melting Confinement Diblock copolymer Rod-coil.

Effect of spacer length on the liquid crystalline property of azobenzene-containing ABA-type triblock copolymers via ATRP

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Chinese Chemical Letters 2007年第9期18卷 1129-1132页

作者： Xin De Tang Long Cheng Gao xing he fan Qi Feng Zhou Institute of New Materials Shandong Jiaotong UniversityJi’nan 250023China Department of Polymer Science and Engineering College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

The effect of flexible spacer length on the liquid crystalline property of ABA-type triblock copolymers containing azobenzene groups was investigated. For the study, the monomers, n-[4-(4-ethoxyphenylazo)phenoxy]alkyl methacrylates with varying methylene groups (n = 0, 2, 6) were used to synthesize a series of azobenzene-containing amphiphilic triblock copolymers PAnC–PEG–PAnC by atom transfer radical polymerization (ATRP). Differential scanning calorimetry (DSC), polarizing optical microscopy (POM), and one-dimensional X-ray diffraction (1D WAXD) have shown that the glass transition temperatures of these copolymers decreased with increasing n, PA0C–PEG–PA0C has no mesophase, while both PA2C–PEG–PA2C and PA6C–PEG–PA6C have a nematic mesophase. These differences derive from the length of spacer groups between the polymer backbone and side-chain LC monomers.

关键词： Spacer group Liquid crystalline property Azobenzene Triblock copolymer Atom transfer radical polymerization (ATRP)

Synthesis and characterization of H-type amphiphilic liquid crystalline block copolymers by ATRP

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Chinese Chemical Letters 2008年第2期19卷 237-240页

作者： Xin De Tang Long Cheng Gao xing he fan Qi Feng Zhou Institute of New Materials Shandong Jiaotong University Ji＇nan 250023 China Department of Polymer Science and Engineering College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

H-type amphiphilic liquid crystalline block copolymers containing azobenzene were synthesized by atom transfer radical polymerization （ATRP）. Macroinitiators prepared by the esterification between poly（ethylene oxide）（PEG） and 2,2-dichloroacetyl chloride were utilized to initiate the polymerization of 6-[4-（4-ethoxyphenylazo）phenoxy]hexyl rnethacrylate （M6C）. The resulting macroinitiators and block copolymers were characterized by ^1H NMR, gel permeation chromatography （GPC）. Polarizing optical microscopy （POM） and differential scanning calorimetry （DSC） preliminarily revealed the liquid crystalline property of these block copolymers. This series of liquid crystalline block copolymers are promising in some areas, such as optical data storage, optical switch, and molecular devices.

关键词： H-type Amphiphilic Block copolymer Liquid crystalline property Atom transfer radical polymerization (ATRP)

Synthesis and Self-assembly of a Linear Coil-Coil-Rod ABC Triblock Copolymer

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Chinese Journal of Polymer Science 2014年第11期32卷 1524-1534页

作者： Ling-ying Shi Yu Pan Qi-kai Zhang Yu Zhou xing-he fan 沈志豪 Beijing National Laboratory for Molecular Sciences Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking University College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan University

An interesting order-order transition between two different complex nanostructures was observed in a new liquid crystalline linear coil-coil-rod ABC triblock copolymer（tri BCP）. First, the ABC tri BCP, poly（dimethylsiloxane）-bpolystyrene-b-poly{2,5-bis[（4-methoxyphenyl）oxycarbonyl]styrene}（PDMS-b-PS-b-PMPCS）, was synthesized through sequential atom transfer radical polymerization. The degrees of polymerization of PDMS, PS, and PMPCS blocks are 58, 159, and 106, and the corresponding volume fractions of PDMS, PS, and PMPCS are 0.09, 0.29, and 0.62, respectively. The phase behaviors of the PDMS-b-PS diblock copolymer precursor and the final triblock copolymer were studied by smallangle X-ray scattering, one-dimensional wide-angle X-ray scattering, and transmission electron microscopy experiments. The PDMS-b-PS precursor self-assembles into hexagonally packed cylinders with a relatively small periodic size after thermal annealing. When the triblock copolymer is annealed at a relatively low temperature（120 ○C） at which the PMPCS block is in the amorphous state, the tri BCP forms core-shell hexagonally packed cylinders（CSH） with a relativly large periodic size. After the tri BCP is annealed above 140 ○C at which the PMPCS block transforms to the liquid crystalline（LC） phase, the nanophase-separated structure transforms to a three-phase four-layer lamellar structure（LAM-3P4L）. Thus, accompanied with the transition of the PMPCS blocks from the amorphous state to the LC phase, the order-order transition from CSH to LAM-3P4 L occurs in the PDMS-b-PS-b-PMPCS ABC tri BCP.

关键词： Coil-coil-rod triblock copolymer Self-assembly Order-order transition Liquid crystalline polymer Complex nanostructures.

Homeotropic Alignment and Selective Adsorption of Nanoporous Polymer Film Polymerized from Hydrogen-bonded Liquid Crystal

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Chinese Journal of Polymer Science 2020年第11期38卷 1185-1191,I0006页

作者： An-Qi Xiao Xiao-Lin Lyu Hong-Bing Pan Zhe-Hao Tang Wei Zhang Zhi-Hao Shen xing-he fan 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 100871China

Nano porous polymer film with a hexagonal colum nar(Coln)structure was fabricated by templated hydroge n-bonding discotic liquid crystals containing methacrylate functional *** supramolecular hydrogen-bonded complex T3Ph-L is composed of a 1,3/5-tris(1Hbenzo[d]imidazol-2-yl)benzene(T3Ph)core molecule as the hydrogen-bonding acceptor and 3,4,5-tris((11-(methacryloyloxy)undecyl)oxy)benzoic acid(L)peripheral molecules as *** the Colh structure is always retained after self-assembly,photo-crosslinking,and removal of the template *** nanoporous polymer film can retain the Colh phase even under the dry condition,which indicates more possibilities for practical applicati *** chemical modificati on of the inner wall of the nano pores,the nan oporous polymer film with pores of about 1 nm selectively adsorbs ionic dyes,and the adsorption process is spontaneous and exothermic in *** alignment can be obtained when the blend complex was sandwiched between two modified glasses after annealing by slow cooling,which shows that the nanoporous polymer film has potential in applications such as nanofiltration.

关键词： Liquid crystal Hydrogen bonding Homeotropic alignment Nanoporous polymer film Selective adsorption

Synthesis and Self-assembly of a Triarm Star-shaped Rod-Rod Block Copolymer

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Chinese Journal of Polymer Science 2015年第5期33卷 709-720页

作者： Feng Zhou 周庆翰 Hai-jian Tian Chang-sheng Li Yu-dong Zhang xing-he fan 沈志豪 Beijing National Laboratory for Molecular Sciences Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking University College of Chemical & Environment Protection Southwest University for Nationalities

We designed and synthesized a triarm star-shaped rod-rod block copolymer（BCP）,（poly{2,5-bis[（4-methoxyphenyl）-oxycarbonyl]styrene}-block-poly（γ-benzyl-L-glutamate））3,（PMPCS-b-PBLG）3. The triarm core with three PMPCS-N3 segments was prepared by copper-mediated atom transfer radical polymerization of 2,5-bis[（4-methoxyphenyl）-oxycarbonyl]styrene initiated by a trifunctional initiator and a subsequent azide reaction. And the PBLG block with alkyne functionality was synthesized through ring-opening polymerization of γ-benzyl-L-glutamate N-carboxyanhydride initiated by propargylamine. Finally, Huisgen＇s 1,3-dipolar cycloaddition was employed to combine the triarm（PMPCS-N3）3 and PBLG segments. The chemical structure of the BCP was confirmed by 1H-NMR spectroscopy, Fourier-transform infrared spectroscopy, and gel permeation chromatographic analysis. Results from differential scanning calorimetry, polarized light microscopy, one-dimensional and two-dimensional wide-angle X-ray diffraction, and transmission electron microscopy techniques demonstrate that the triarm star-shaped rod-rod BCP self-assembles into a hexagon-in-lamella morphology, with the PMPCS block in the columnar nematic phase and the PBLG block in the hexagonal columnar arrangement packed in bilayers due to the rigid nature of the two blocks and the covalent connections in the star-shaped BCP.

关键词： Star polymer Liquid crystalline polymer Block copolymer Self-assembly

Ordered Bicontinuous Network Structures Regulated by Orientational Interactions in a Rod-Coil Block Copolymer

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Chinese Journal of Polymer Science 2024年第5期42卷 636-642,I0008页

作者： Xiao-Lin Lyu Shi-Chu Yang An-Qi Xiao Ping-Ping Hou Wei Zhang Hong-Bing Pan Zhi-Hao Shen xing-he fan Qi-Feng Zhou Beijing National Laboratory for Molecular Sciences Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing100871China Key Laboratory of Advanced Materials Technologies International(HongKong Macao and Taiwan)Joint Laboratory on Advanced Materials TechnologiesCollege of Materials Science and EngineeringFuzhou UniversityFuzhou350108China

The rich phase behavior of block copolymers(BCPs)has drawn great attention in recent ***,the double diamond(DD)phase is rarely obtained because of the competition between the minimization of interfacial energy and packing ***,a rod-coil BCP containing mesogen-jacketed liquid crystalline polymer is designed to acquire ordered bicontinuous network *** reduction of internal energy originating from the orientational interaction among the rod blocks can compensate for the free energy penalty of packing frustration to stabilize the DD *** resulting BCP can also experience lamellae-to-DD and double gyroid-to-lamellae transitions by changing the annealing *** results make the rod-coil BCP an excellent candidate for the self-assembly of ordered network structures,demonstrating great potential in nanopatterning and metamaterials.

关键词： Block copolymer Rod-coil Ordered bicontinuous phase Double diamond Double gyroid

SYNTheSIS AND PROPERTIES OF A NEW AZOBENZENE SIDE-CHAIN POLYMER CONTAINING A TEMPO RADICAL

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Chinese Journal of Polymer Science 2002年第4期20卷 285-290页

作者： Yong Zhang Ze-da Xu xing-he fan Xiao-fang Chen Xin-hua Wan Qi-feng Zhou Department of Polymer Science and Engineering College of Chemistry and Molecular Engineering Peking University, Beijing 100871, China Department of Polymer Science and Engineering College of Chemistry and Molecular Engineering Peking University 北京 100871

To allow anisotropies of optical properties in a magnetic field, nitroxide radical is introduced into the ortho-position of the phenylene ring in the side chain. A new azobenzene side-chain polymer (TEMPO-PAZ) containing TEMPO radical was synthesized. The polymer has a good solubility in organic solvents. The ESR spectrum of the polymer indicated three absorption lines characteristic of TEMPO radical. The optical phase conjugated responses (I-4) of the polymer films were investigated by degenerate four-wave mixing (DFWM). The experimental results showed that optical phase conjugated response of the TEMPO-PAZ could be easily controlled by choosing the appropriate direction of magnetic field presumably due to the nitroxide radical in the TEMPO-PAZ molecular structure. For the polymer investigated here, the nitroxide radical was introduced to increase optical phase conjugated response intensity in a magnetic field, aiming originally at searching for a new photo-active organic magnetic multifunctional materials.

关键词： azobenzene nitroxide radical polymer photo-active organic magnetic materials optical phase conjugated responses