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Chinese Journal of Structural Chemistry 2006年第8期25卷 957-964页

作者： JIANG Ning-Yi LI Song-Lin Department of Chemistry College of Science Tianjin University Tianjin 300072 China

A new double betaine 1,1′-（propane-1,3-diyl）dipyridinium-4-carboxylate L has been synthesized. Reaction of 1, 1′-（propane-1,3-diyl）dipyridinium-4-carboxylate tetrahydrate 1 with Co（ClO4）2-6H2O leads to the formation of a new Co（Ⅱ） coordination compound, namely [Co（H2O）6]-2H2O-2L-2ClO4 2. The crystal structures of 1 and 2 have been determined by single-crystal X-ray diffraction method. Crystal data for 1. monoclinic, space group C2/c, a = 18.945（4）, b = 7.700（2）, c = l 1.888（2）A,β = 101.67（3）°, V = 1698.3（6） A^3, Z = 4, F（000） = 760.0, Dc = 1.402 g/cm^3, the final R = 0.0607 and wR = 0.1607 for 950 observed reflections （1 〉 2σ（I））; and those for 2： monoclinic, space group P21/c, a = 17.982（1）, b = 15.879 （1）, c = 7.0716（5）/A,β= 100.675（1）°, V= 1984.3（3） ,A^3 Z= 4, F（000） = 1010.0, Dc = 1.631 g/cm^3, the final R = 0.0316 and wR = 0.0896 for 3784 observed reflections （1 〉20（I））. Crystal structure analysis indicates that in 1, molecules of L in a ＂V-shaped＂ conformation are linked to chains sustained by O-H…O hydrogen bonds between carboxylate groups and solvent water molecules. The chains are joined by O-H…O and C-H…O hydrogen bonds to further expand into a three-dimensional structure. For 2, molecules of L in a ＂Z-shaped＂ conformation are linked by hydrogen bonds between carboxylate groups and aqua ligands to form a chain of loops running down the b axis. The （2D→2D） polythreading in compound 2 represents the mode of parallel interpenetration of 2D sheets, having polyrotaxane character.

关键词： 1,1′-(propane-1,3-diyl)dipyridinium-4-carboxylate polyrotaxane hydrogen bonding betaine derivative

Glutathione as the End Capper for Cyclodextrin/PEG polyrotaxanes

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Chinese Journal of Polymer Science 2014年第8期32卷 1003-1009页

作者： Qiao Song Zhi Luo 童新明 Yi Du Yanbin Huang Department of Chemical Engineering Tsinghua University

A facile one-pot synthesis of α-cyclodextrin-based polyrotaxane （PR） in aqueous solution is reported, where the peptide glutathione was used as the end-capping agent and the thiol-ene Michael addition was used as the end-capping reaction. Both polyrotaxanes with low threading ratio and high threading ratio were successfully obtained. In contrast to the conventionally used multiple-step synthesis methods and hydrophobic end cappers, this one-pot aqueous synthesis as well as the biocompatibility of the end-capping agent could result in a much more biocompatible PR to be used as biomaterials.

关键词： polyrotaxane Cyclodextrin Polyethylene glycol Glutathione Biocompatibility.

SYNTHESIS AND CHARACTERIZATION OF polyrotaxaneS MADE FROM α-CDs THREADED ONTO TRIBLOCK COPOLYMERS WITH PEG AS A CENTRAL AXLE AND FLANKED BY TWO LOW MOLECULAR WEIGHT POLYSTYRENES AS OUTER STOPPERS

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Chinese Journal of Polymer Science 2008年第6期26卷 723-732页

作者：冯增国 School of Materials Science and Engineering Beijing Institute of Technology

A study has been conducted on the synthesis and characterization of a kind of novel polyrotaxanes comprisingα- cyclodextrins (α-CDs) threaded on triblock eopolymers with poly(ethylene glycol) (PEG) as a central axle and flanked by two low molecular weight polystyrenes as outer *** was allowed to telomerize with polypseudorotaxanes as chain transfer agents made from the self-assembly of a distal thiol-capped PEG with a varying amount ofα-CDs in the presence of a redox initiation system at 40~C i...

关键词： polyrotaxane α-Cyclodextrin Polystyrene Radical telomerization.

Slightly Cross-Linked polyrotaxanes Made by Linking α-Cyclodextrins Entrapped in polyrotaxanes Using Hexamethylene Diisocyanate

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Chinese Journal of Chemistry 2012年第10期30卷 2453-2460页

作者：李硕王锦姜岚叶霖张爱英冯增国 School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China

In this study polyrotaxane （PR）-based triblock copolymers were first synthesized via the atom transfer radical polymerization （ATRP） of N-isopropylacrylamide initiated with the self-assembly of a distal 2-bromoisobutyryl end-capped Pluronie 17R4 with a varying amount of a-cyclodextrins （a-CDs） in the presence of CuCI/PMDETA at 25 ℃ in aqueous solution. The a-CDs entrapped on the copolymer chain were then linked with hexamethylene diisocyanate to give rise to novel slightly cross-linked polyrotaxanes （SCPRs） in DMF at 45 ℃. The structures of the PR-based triblock copolymers and SCPRs were characterized by 1H NMR, 13C CP/MAS, GPC and TGA analy- ses. The number-average molecular weight of the resulting SCPRs was nearly three and five times of their precursor after linking with a low polydispersity index range of 1.08--1.28. The thermo-responsive transition of both PR-based supramolecular polymers in aqueous solution was demonstrated by turbidity measurements and the self-aggregated morphologies were also evidenced by TEM observations.

关键词： α-cyclodextrin polyrotaxane ATRP poly(N-isopropylacrylamide) hexamethylene diisocyanate

Supramolecular Micelles and Reverse Micelles Based on Cyclodextrin polyrotaxanes

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Chinese Journal of Chemistry 2014年第1期32卷 73-77页

作者： Qiao Jin Gongyan Liu Jian Ji[*] MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University Hangzhou Zhejiang 310027 China Email: Jian Ji (jijian@***)[*]MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University Hangzhou Zhejiang 310027 China Tel.: 0086-0571-87953729 Fax: 0086-0571-87953729

A new supramolecular self-assembly approach to construct micelles and reverse micelles was ***-hydrophilic block copolymers poly(ethylene oxide)-b-poly(N-isopropylacrylamide) (PEO-b-PNIPAAm) was synthesized via atom transfer radical polymerization (ATRP) using PEO *** of the lower critical solution temperature (LCST) phase behavior of PNIPAAm,PEO-b-PNIPAAm block copolymers self-assembled to form PNIPAAm-core micelles at 40 ℃.The PNIPAAm-core micelles were disassembled to unimers when the temperature was decreased to 25 ℃.But the addition of α-cyclodextrins (α-CDs) could induce the formation of PNIPAAm-shell micelles because of the 'channel-type' crystallities induced by PEO/α-CDs *** assembly and disassembly procedure of micelles and reverse micelles were investigated by dynamic light scattering (DLS),X-ray diffraction (XRD),1H NMR and transmission electron microscopy (TEM).

关键词： cyclodextrin polyrotaxane reverse micelle supramolecular

Distinguishing channel-type crystal structure from dispersed structure in 13-cyclodextrin based polyrotaxanes via FTIR spectroscopy

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Frontiers of Computer Science 2011年第3期5卷 329-334页

作者： Jin WANG Pei-Jing WANG Peng GAO Lan JIANG Shuo LI Zeng-Guo FENG School of Materials Science and Engineering Beijing Institute of Technology Beijing 100081 China

Combining with XRD analysis, Fourier transform infrared （FTIR） spectroscopy is employed to discern the self-assembled structures of β-cyclodextrins （β-CDs） threaded onto the polymer backbone in the polyrotaxanes （PRs） by means of the relative changes of absorption intensity of the characteristic peaks of β-CDs at 1153 and 1025 cm^-1. For quantitative analysis, six parameters are proposed to describe the relative absorption intensity variations of these peaks associated with a channel-type crystal structure or a dispersed structure of β-CDs entrapped. Among them, absorbance ratio （AR）, relative absorbance difference （RAD） and transmittance difference （TD） values are suitable. When the AR, RAD and TD data get below 1.04, 4.8 and 1.27, respectively, the PRs obtained would possess a dispersed structure. If these values go beyond 1.32, 34,5 and 9.47, respectively, they would hold a channel-type crystal structure. This finding provides a useful judgment to distinguish the self-assembled structures of β-CDs residing along the polymer backbone in the PRs.

关键词： FTIR polyrotaxane β-cyclodextrin self-assembled structure

Structure and Mechanical Properties of Waterborne Polyurethane-based Composites Filled with Self-assembled Supramolecular Nanoplatelets

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Journal of Wuhan University of Technology(Materials Science) 2013年第4期28卷 773-780页

作者：张芳范红蕾 HUANG Jin 苏忠民 HE Lihong Institute of Functional Material Chemistry Faculty of Chemistry Northeast Normal University College of Chemical Engineering Wuhan University of Technology Center for Nanophase Materials Sciences Oak Ridge National Laboratory

New composites of waterborne polyurethane （WPU） as a matrix were prepared by incorporating rigid supramolecular nanoplatelets （SNs） as filler, which were self-assembled by the selective inclusion of β-cyclodextrin （β-CD） onto poly（propylene oxide）（PPO） segment in the poly（ethylene oxide）- block-PPO-block-poly（ethylene oxide）（PEO-b-PPO-b-PEO）. It is worth noting that, when the loading level of SN is lower than 3wt%, the SNs with moderate PEO length result in the simultaneous increase in strength, elongation and Young＇s modulus in contrast with neat WPU. If there is no stretching free PEO chain, both strength and elongation decrease in spite of an increase in Young＇s modulus. However, too long PEO chains result in the decrease of mechanical performances while the relatively higher loading-level of SNs also inhibits the enhancement of strength and elongation.

关键词： waterborne polyurethane supramolecular nanoplatelets polyrotaxane cyclodextrin inclusion composites mechanical properties