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SYNTHESIS OF NOVEL LIQUID CRYSTALLINE POLY(METH)ACRYLATES CONTAINING SILOXANE SPACER AND TERPHENYLENE MESOGENIC UNIT

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Chinese Journal of polymer science 2000年第2期18卷 101-107页

作者： zhi-qian Zang Yu-fei Luo Dong zhang Xin-hua Wan Qi-feng Zhou department of {3. science & engineering, College of chemistry, peking university, beijing 100871, china peking Univ Coll Chem Dept Polymer Sci & Engn Beijing 100871 Peoples R China

Novel side-chain liquid-crystalline poly(meth)acrylates were synthesized using 1-(3.hydroxyl-propyl)-3.[(4 '-cyano-p-terphenyloxycarbonyl)alkyl]-1,1,3.3.tetramethyldisiloxane as the key intermediate. The polymers used a disiloxane moiety as decoupling spacer with cyano-p-terphenyl as mesogenic unit. The products were characterized by NMR, GPC, DSC and polarizing optical microscopy. All the polymers with cyano-p-terphenyl mesogens formed a stable mesophase. However, if the mesogenic unit is replaced by cyano-p-biphenyl, the liquid crystalline character will be lost. The results also showed that the decoupling is incomplete even if a complex and very flexible decoupling spacer is deliberately incorporated to obtain the highest possible decoupling effect.

关键词： liquid crystalline polymers polyacrylates 4 ''-cyano-p-terphenyl

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 {3. and engineering College of chemistry and molecular engineering peking university, beijing 100871, china peking Univ Coll Chem & Mol Engn Dept Polymer Sci & Engn Beijing 100871 Peoples R China

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

RING-OPENING polymerIZATION OF TRIMETHYLENE CARBONATE BY CALIX[8]ARENE-NEODYMIUM

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Chinese Journal of polymer science 2000年第1期18卷 77-80页

作者： Ling Ge zhi-quan Shen Yi-feng zhang Qiao-hong Huang {3. of polymer science and engineering, Zhejiang university, Hangzhou 3.0027, china Zhejiang Univ Dept Polymer Sci & Engn Hangzhou 310027 Peoples R China

Ring-opening polymerization of trimethylene carbonate (TMC) with a rare earth calixarene compound as catalyst has been studied for the first time. The effect of TMC/Nd (molar ratio) and polymerization conditions were investigated in detail. It was found that calix[8]arene-neodymium is a highly effective catalyst for the bulk polymerization of TMC and gives high {3. weight (M-v = 60,000) polymer. The optimum conditions of TMC polymerization were found to be as follows:TMC/Nd (molar ratio) = 2,000, 80 degrees C, 16 h. The polymers were characterized by NMR, GPC and DSC. Studying the mechanism by NMR showed that the polymerization of TMC catalyzed by calix[8]arene-neodymium proceeds via a cationic mechanism.

关键词： ring-opening polymerization trimethylene carbonate calixarene-neodymium

Distinguishing malignant from normal stomach tissues and its in vivo, in situ measurement in operating process using FTIR Fiber-Optic techniques

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science china chemistry 2005年第2期48卷 167-175页

作者： XU Yizhuang1, YANG Limin1, XU zhi3. ZHAO Ying2, LING Xiaofeng3. LI Qingbo1, WANG Jiansheng4, zhang Nengwei3. zhang Yuanfu1 & WU Jinguang1 1. The State Key Laboratory of Rare Earth Materials and Applications, College of {3. and molecular engineering, peking university, beijing 100871, china 2. Institute of {3., Chinese Academy of sciences, beijing 100080, china 3. department of Surgery, Third Hospital, peking university, beijing 100083. china 4. department of Oncology Surgery, the First Hospital of Xi’an Jiaotong university, Xi’an 710061, china Correspondence should be addressed to Wu Jinguang (email: wujg@***) 1. The State Key Laboratory of Rare Earth Materials and Applications College of Chemistry and Molecular Engineering Peking University 100871 Beijing China 2. department of Surgery Third Hospital Peking University 100083 Beijing China 3. Institute of chemistry Chinese Academy of Sciences 100080 Beijing China 4. department of Oncology Surgery the First Hospital of Xi’an Jiaotong University 710061 Xi’an China

Gastric tissue samples were studied using mid-IR fiber-optic attenuated total reflectance (ATR) spectroscopy. FTIR spectra of 90 tissue samples from 48 patients, including 3. normal and 58 malignant tissue samples, were chosen as examples. Malignancy was usually characterized by the absence of CH and C=O bands, a weak amide II band near 1545 cm-1, a shift of the amide I band to lower wave number, a decrease in the ～1450 cm-1 peak to less than the～1400 cm-1 peak. Subtraction spectra indicate that the amide I and amide II bands of normal and malignant tissues have larger differences in peak positions and relative intensities. The statistical analysis results confirm this conclusion. The results indicate that FTIR fiber optic techniques provide important information about cancerous tissue of the stomach, which can be used to differentiate the malignant tissue from the normal tissue. Based on the above results we successfully realize the detection of the tumor tissues of digestive tract in vivo and in situ. And the results of detection cancer near operating room and in vivo and in situ in the operating room are consistent with the conclusions for the samples stored in liquid N2, which is the basis for the clinical application.

关键词： FTIR, Fiber-Optics, stomach tissues, cancer, diagnosis.

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

NITROXIDE-MEDIATED FREE RADICAL SYNTHESIS OF MESOGEN-JACKETED LIQUID CRYSTAL polymerS

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Chinese Journal of polymer science 1999年第2期17卷 189-192页

作者： Xin-hua Wan Hui-lin Tu Ying-feng Tu Dong zhang Ling Sun Qi-feng Zhou Yu-ping Dong Mao Tang department of polymer {3. & engineering, College of chemistry, peking university, beijing 100871, china department of Materials & Chemical engineering, beijing Institute of Technology, beijing 100081, china peking Univ Coll Chem Dept Polymer Sci & Engn Beijing 100871 Peoples R China beijing Inst Technol Dept Chem & Mat Engn Beijing 100081 Peoples R China

The first TEMPO-mediated 'living' free radical polymerization of liquid crystalline monomer, 2, 5-bis[(4-methoxyphenyl)oxycarbonyl]styrene (MPCS), was carried out at 13. degrees C with BPO as an initiator. The molecular weight of the polymer can be varied from rather low values to high values while maintaining narrow polydispersity. It was observed that the polymerization of MPCS proceeded much faster than that of styrene. A tentative explanation for this fast polymerization was suggested.

关键词： TEMPO 'living' free radical polymerization mesogen-jacketed liquid crystal polymer mesophase polymerization

The superiority of nonconjugated structures in fluorescence:through-space ***-bond charge transfer

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science china chemistry 2024年第9期67卷 3121-3130页

作者： Weihao Tu Zuping Xiong Lei Wang Jianyu zhang Jing zhi Sun Haoke zhang Ben Z{3. Tang MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310058China Zhejiang-Israel Joint Laboratory of Self-Assembling Functional Materials ZJU-Hangzhou Global Scientific and Technological Innovation CenterZhejiang UniversityHangzhou 311215China Centre of Healthcare Materials Shaoxing InstituteZhejiang UniversityShaoxing 312000China department of chemistry Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and ReconstructionThe Hong Kong University of Science and TechnologyHong Kong 999077China School of science and engineering Shenzhen Institute of Aggregate Science and TechnologyThe Chinese University of Hong KongShenzhen(CUHK-Shenzhen)Guangzhou 518172China

Constructing charge transfer(CT)state by introducing donor(D)and acceptor(A)is an efficient strategy to regulate the photophysical properties of luminescent *** CT-type luminophores are built onπ-conjugated fused-ring structures,which always show hybrid CT/locally excited(LE)states and luminescence quenching effect in the aggregate *** this work,eight conjugated biphenyl(BP)and nonconjugated diphenylmethane(DPM)derivatives with different donors and acceptors are synthesized to investigate the CT *** photophysical characterization and theoretical calculation demonstrate that the through-space CT(TSCT)in nonconjugated DA-DPM exhibit superior photophysical performance than the conjugated DA-BP with through-bond CT(TBCT),the main manifestations are as follows:(1)TSCT luminophores produce longer maximum emission wavelength(λ_(em))than the corresponding TBCT *** example,the longest λ_(em)of DMA-CN-DPM(DMA,dimethylamino)is 621 nm but the corresponding λ_(em)of DMA-CN-BP is only 480 nm.(2)TSCT-based DA-DPM demonstrates more sensitive responsiveness to environmental stimuli such as temperature and polarity.(3.Complete separation of the the highest occupied molecular orbital(HOMO)and the lowest unoccupied molecular orbital(LUMO)distribution exists in all kinds of conformation of DA-DPM,which was hard to realize in conjugated DA-BP.

关键词： through-space charge transfer through-space conjugation clusteroluminescence diphenylmethane

DEGRADABLE THERMORESPONSIVE POLYESTERS BY ATOM TRANSFER RADICAL POLYADDITION AND CLICK chemistry

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DEGRADABLE THERMORESPONSIVE POLYESTERS BY ATOM TRANSFER RADI...

Tunable Phase Structure of Side-chain Liquid Crystalline polymers Enabled by molecular engineering of Dual Mesogenic Cores

第五届国际高分子化学学术讨论会

作者： Li-Jing zhang Bo-Tao Dong Fu-Sheng Du and Zi-Chen Li beijing National Laboratory for molecular {3.s(BNLMS) Key Laboratory of polymer chemistry& Physics of Ministry of Education department of polymer {3.&engineering College of chemistry and molecular engineering {13. university beijing 100871 china.

＜正＞LCST-type thermoresponsive polymers have found a variety of applications in biomedical science ranging from smart surfaces,bio-sensing and tissue engineering to intelligent drug/gene delivery.1 However,as most of the above polymers are based on carbon-carbon backbone,the non-degradability may limit their in vivo

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Chinese Journal of polymer science 2024年第10期42卷 1459-1469,I0009页

作者： Wen-Huan Yao Lan-Sheng Liu Jie Zhao Yan-Xia Wang An-zhi Ma Zheng-Rui Ma Lan-Ying zhang Ruo-Chen Lan College of chemistry and Chemical engineering Hunan UniversityChangsha410082China Key Laboratory of Eco-Functional polymer Materials of the Ministry of Education Key Laboratory of Eco-Environmental Polymer Materials of Gansu ProvinceCollege of Chemistry and Chemical EngineeringNorthwest Normal UniversityLanzhou730070China department of Materials science and engineering College of EngineeringPeking UniversityBeijing100871China Institute of Advanced Materials&Key Lab of Fluorine and Silicon for Energy Materials and chemistry of Ministry of Education College of Chemistry and Chemical EngineeringJiangxi Normal UniversityNanchang330022China

A series of novel side-chain liquid crystalline(SCLC)copolymers were synthesized by attaching two distinct mesogenic units,namely a chiral cholesteryl-based monomer(M1)and an achiral biphenyl-based monomer(M2),to a poly(3.mercaptopropylmethylsiloxane)(PMMS)backbone via thiol-ene click *** influence of side chain composition on the self-assembly behavior and phase structures of these SCLC copolymers was systematically investigated using different *** indicate that three distinct liquid crystalline phases and four unique molecular configurations were identified within the polymer series,with the emergence of the liquid crystalline phase being a synergistic outcome of the two distinct side *** study underscores the critical influence of side chain dimensions,rigidity,and spatial volume on the self-assembly structures and phase characteristics of liquid crystalline polymers,providing valuable insights for the rational design and development of advanced functional materials with tailored properties.

关键词： Liquid crystalline copolymers Self-assembly Phase structure Chiral molar ratio