An H‐shaped polymer bonding β‐cyclodextrin at branch points: Synthesis and influences of attached β‐cyclodextrins on physical properties

We report on the synthesis of an H‐shaped polymer bonding β‐cyclodextrin (β‐CD) at branch points and influences of attached β‐CD on physical properties. First, a poly(ethylene glycol)(PEG)‐based functional macroinitiator bearing two azidos and four chlorines at chain‐ends (PEG‐2N₃(‐4Cl)) was prepared via terminal modification reactions. Then, PEG‐2N₃(‐4Cl) was applied to initiate the atom transfer radical polymerization of N‐isopropylacrylamide, leading to the synthesis of an H‐shaped block polymer with PEG as the central chain and poly(N‐isopropylacrylamide) (PNIPAM) as side‐arms (PEG‐2N₃(‐4PNIPAM)). Azido groups were at the branch points of the polymer. Finally, the click reaction between PEG‐2N₃(‐4PNIPAM) and alkynyl monosubstituted β‐cyclodextrin (β‐CD) afforded another H‐shaped polymer with two β‐CDs bonding at the polymer branch points (PEG‐2CD(‐4PNIPAM)). The glass transition temperature (T_g) and lower critical solution temperature (LCST) of the H‐shaped polymer increased after the attachment of β‐CD. The self‐assembly and thermal responsive behaviors, as well as the encapsulation behaviors of PEG‐2CD(‐4PNIPAM) were also altered. When temperature was below the LCSTs, PEG‐2N₃(‐2PNIPAM) dissolved in water molecularly, whereas PEG‐2CD(‐4PNIPAM) could self‐assemble into nano‐sized micelles. After the LCST transitions, PEG‐2N₃(‐4PNIPAM) aggregated into micron‐sized unstable particles, whereas PEG‐2CD(‐4PNIPAM) transformed into PNIPAM‐cored nanomicelles. Besides, PEG‐2CD(‐4PNIPAM) can encapsulate doxorubicin below its LCST due to the formation of micelles. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013     

超支化聚硅碳烷-g-环糊精聚合物刷的合成与表征

通过硅氢加成反应和核多步法聚合合成出超支化聚硅碳烷(HBP),并对其端基进行了硅氢化、羟基化和酰氯化三步改性得到大分子引发剂HBP-Cl;再用其引发甲基丙烯酸N,N-二甲氨基乙酯(DMA)进行原子转移自由基聚合(ATRP),得到超支化聚硅碳烷-g-聚甲基丙烯酸N,N-二甲氨基乙酯(HBP-g-PDMA),最后将单-6-碘代β-CD通过离子键固载到PDMA链上,得到超支化聚硅碳烷-g-环糊精聚合物刷(HBP-g-PDMA-β-CD).采用FTIR、1H-NMR、13C-NMR、29Si-NMR对其结构进行了表征,利用凝胶渗透色谱/多角度激光光散射(SEC/MALLS)联用仪和激光粒度分析仪研究了其高分子的精细结构,并通过元素分析研究了固载时间对β-CD固载量的影响.     

Cyclodextrin‐overhanging hyperbranched core‐double‐shell miktoarm architectures: Synthesis and gradient stimuli‐responsive properties

We report the synthesis and gradient stimuli‐responsive properties of cyclodextrin‐overhanging hyperbranched core‐double‐shell miktoarm architectures. A ionic hyperbranched poly(β‐cyclodextrin) (β‐CD) core was firstly synthesized via a convenient “A₂+B₃” approach. Double‐layered shell architectures, composed of poly(N‐isopropyl acrylamide) (PNIPAm) and poly(N,N‐dimethylaminoethyl methacrylate) (PDMAEMA) miktoarms as the outermost shell linked to poly(N,N‐diethylaminoethyl methacrylate) (PDEAEMA) homoarms which form the inner shell, were obtained by a sequential atom transfer radical polymerization (ATRP) and parallel click chemistry from the modified hyperbranched poly(β‐CD) macroinitiator. The combined characterization by ¹H NMR, ¹³C NMR, ¹H‐²⁹Si heteronuclear multiple‐bond correlation (HMBC), FTIR and size exclusion chromatography/multiangle laser light scattering (SEC/MALLS) confirms the remarkable hyperbranched poly(β‐CD) core and double‐shell miktoarm architectures. The gradient triple‐stimuli‐responsive properties of hyperbranched core‐double‐shell miktoarm architectures and the corresponding mechanisms were investigated by UV–vis spectrophotometer and dynamic light scattering (DLS). Results show that this polymer possesses three‐stage phase transition behaviors. The first‐stage phase transition comes from the deprotonation of PDEAEMA segments at pH 9–10 aqueous solution under room temperature. The confined coil‐globule conformation transition of PNIPAm and PDMAEMA arms gives rise to the second‐stage hysteretic cophase transition between 38 and 44 °C at pH 10. The third‐stage phase transition occurs above 44 °C at pH = 10 attributed to the confined secondary conformation transition of partial PDMAEMA segments. This cyclodextrin‐overhanging hyperbranched core‐double‐shell miktoarm architectures are expected to solve the problems of inadequate functionalities from core layer and lacking multiresponsiveness for shell layers existing in the dendritic core‐multishell architectures. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012     

Synthesis and characterization of crystalline graft polymer poly(ethylene oxide)‐g‐poly(ɛ‐caprolactone)2 with modulated grafting sites

The graft polymer poly(ethylene oxide)‐g‐poly(?‐caprolactone)₂ (PEO‐g‐PCL₂) with modulated grafting sites was synthesized by the combination of ring‐opening polymerization (ROP) mechanism, efficient Williamson reaction, with thiol–ene addition reaction. First, the precursor of PEO‐Allyl‐PEO with two terminal hydroxyl groups and one middle allyl group was prepared by ROP of EO monomers. Then, the macroinitiator [PEO‐(OH)₂‐PEO]_s was synthesized by sequential Williamson reaction between terminal hydroxyl groups and thiol–ene addition reaction on pendant allyl groups. Finally, the graft polymer PEO‐g‐PCL₂ was obtained by ROP of ?‐CL monomers using [PEO‐(OH)₂‐PEO]_s as macroinitiator. The target graft polymer and all intermediates were well characterized by the measurements of gel permeation chromatography, ¹H NMR, and thermal gravimetric analysis. The crystallization behavior was investigated by the measurements of differential scanning calorimetry, wide‐angle X‐ray diffraction and polarized optical microscope. The results showed that when the PCL content of side chains reached 59.2%, the crystalline structure had been dominated by PCL part and the crystalline structure formed by PEO part can be almost neglected. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 2239–2247     

β‐cyclodextrin‐based polymeric nano‐receptor: the self‐assembly of cyclodextrin‐appended comb‐copolymer

Well‐defined β‐cyclodextrin (β‐CD)‐appended biocompatible comb‐copolymer ethyl cellulose‐graft‐poly (ε‐caprolactone) (EC‐g‐PCL) was synthesized via the combination of ring‐opening polymerization (ROP) and click chemistry. The resulting products were characterized by ¹H NMR, FT‐IR spectroscopy, and GPC. The synthesized comb‐copolymer could assemble to micelles, with the surface covered by β‐CD. The inclusion with ferrocene derivation was investigated by cyclic voltammetric (CV) experiments, which indicated the potential application of the micelles as nano‐receptors for molecule recognization and controlled drug release. Copyright © 2011 John Wiley & Sons, Ltd.     

Synthesis and application as polymer electrolyte of hyperbranched polyether made by cationic ring‐opening polymerization of 3‐{2‐[2‐(2‐hydroxyethoxy)ethoxy]ethoxymethyl}‐3′‐methyl‐oxetane

A novel cyclic ether monomer 3‐{2‐[2‐(2‐hydroxyethoxy)ethoxy]ethoxy‐methyl}‐3′‐methyloxetane (HEMO) was prepared from the reaction of 3‐hydroxymethyl‐3′‐methyloxetane tosylate with triethylene glycol. The corresponding hyperbranched polyether (PHEMO) was synthesized using BF₃·Et₂O as initiator through cationic ring‐opening polymerization. The evidence from ¹H and ¹³C NMR analyses revealed that the hyperbranched structure is constructed by the competition between two chain propagation mechanisms, i.e. active chain end and activated monomer mechanism. The terminal structure of PHEMO with a cyclic fragment was definitely detected by MALDI‐TOF measurement. A DSC test implied that the resulting polyether has excellent segment motion performance potentially beneficial for the ion transport of polymer electrolytes. Moreover, a TGA assay showed that this hyperbranched polymer possesses high thermostability as compared to its liquid counterpart. The ion conductivity was measured to reach 5.6 × 10^?5 S/cm at room temperature and 6.3 × 10^?4 S/cm at 80 °C after doped with LiTFSI at a ratio of Li:O = 0.05, presenting the promise to meet the practical requirement of lithium ion batteries for polymer electrolytes. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3650–3665, 2006     

Ionic Conductivity of β‐Cyclodextrin–Polyethylene‐Oxide/Alkali‐Metal‐Salt Complex

Highly conductive, crystalline, polymer electrolytes, β‐cyclodextrin (β‐CD)–polyethylene oxide (PEO)/LiAsF₆ and β‐CD–PEO/NaAsF₆, were prepared through supramolecular self‐assembly of PEO, β‐CD, and LiAsF₆/NaAsF₆. The assembled β‐CDs form nanochannels in which the PEO/X⁺ (X=Li, Na) complexes are confined. The nanochannels provide a pathway for directional motion of the alkali metal ions and, at the same time, separate the cations and the anions by size exclusion.     

Asymmetric cyclopolymerization of N‐tert‐butyl‐N‐allylacrylamide in the presence of β‐cyclodextrin

The radical polymerization of N‐tert‐butyl‐N‐allylacrylamide (t‐BAA) was carried out in a dimethyl sulfoxide/H₂O mixture in the presence of β‐cyclodextrin (β‐CD). The polymerization proceeded with the complete cyclization of the t‐BAA unit and yielded optically active poly(t‐BAA). The IR spectrum of the obtained polymer showed that the cyclic structure in the polymer was a five‐membered ring. The optical activity of poly(t‐BAA) increased with an increasing molar ratio of β‐CD to the t‐BAA monomer. The interaction of β‐CD with t‐BAA was confirmed by ¹H NMR and ¹³C NMR analyses of the polymerization system. It is suggested that interaction of the t‐BAA monomer with the hydrophobic cavity of β‐CD plays an important role in the asymmetric cyclopolymerization of t‐BAA. The radical copolymerization of t‐BAA with styrene (St), methyl methacrylate, ethyl methacrylate, or benzyl methacrylate (BMA) also produced optically active copolymers with a cyclic structure from the t‐BAA unit. St and BMA carrying a phenyl group were predicted to compete with t‐BAA for interaction with β‐CD in the copolymerization system. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 2098–2105, 2000     

Supramolecular inclusion complexes of a star polymer containing cholesterol end‐capped poly(ε‐caprolactone) arms with β‐cyclodextrin

A novel hexa‐armed and star‐shaped polymer containing cholesterol end‐capped poly(ε‐caprolactone) arms emanating from a phosphazene core (N₃P₃‐(PCL‐Chol)₆) was synthesized by a combination of ring‐opening polymerization and “click” chemistry techniques. For this purpose, the terminal ? OH groups of the synthesized precursor (N₃P₃‐(PCL‐OH)₆) were converted into –Chol through a series of reaction. Both N₃P₃‐(PCL‐OH)₆ and N₃P₃‐(PCL‐Chol)₆ were then employed in the preparation of supramolecular inclusion complexes (ICs) with β‐cyclodextrin (β‐CD). The latter formed ICs with β‐CD in higher yield. The host–guest stoichiometry (ε‐CL:β‐CD, mol:mol) in the ICs of N₃P₃‐(PCL‐Chol)₆ was found to be 1.2. The formation of supramolecular ICs of N₃P₃‐(PCL‐Chol)₆ with β‐CD was confirmed by using Fourier transform infrared (FTIR) and ¹H nuclear magnetic resonance (NMR) spectroscopic methods, wide‐angle X‐ray diffraction (WAXD), and thermal analysis techniques. WAXD data showed that the obtained ICs with N₃P₃‐(PCL‐Chol)₆ had a channel‐type crystalline structure, indicating the suppression of the original crystallization of N₃P₃‐(PCL‐Chol)₆ in β‐CD cavities. Moreover, the thermal stabilities of ICs were found to be higher than those of the free star polymer and β‐CD. Furthermore, the surface properties of N₃P₃‐(PCL‐Chol)₆ and its ICs with β‐CD were investigated by static contact angle measurements. The obtained results proved that the wettability of N₃P₃‐(PCL‐Chol)₆ successfully increased with the formation of its ICs with β‐CD. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 3406–3420     

pH‐ and β‐cyclodextrin‐responsive micelles based on polyaspartamide derivatives as drug carrier

A novel kind of graft polymer poly(aspartic acid)‐ethanediamine‐g‐adamantane/methyloxy polyethylene glycol (Pasp‐EDA‐g‐Ad/mPEG) was designed and synthesized for drug delivery in this study. The chemical structure of the prepared polymer was confirmed by proton NMR. The obtained polymer can self‐assemble into micelles which were stable under a physiological environment and displayed pH‐ and β‐cyclodextrin (β‐CD)‐responsive behaviors because of the acid‐labile benzoic imine linkage and hydrophobic adamantine groups in the side chains of the polymer. The doxorubicin (Dox)‐loaded micelles showed a slow release under physiological conditions and a rapid release after exposure to weakly acidic or β‐CD environment. The in vitro cytotoxicity results suggested that the polymer was good at biocompatibility and could remain Dox biologically active. Hence, the Pasp‐EDA‐g‐Ad/mPEG micelles may be applied as promising controlled drug delivery system for hydrophobic antitumor drugs. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 1387–1395     

Synthesis and characterization of a poly(N‐isopropylacrylamide) with β‐cyclodextrin as pendant groups

A novel linear poly(N‐isopropylacrylamide) (PNIPA) with β‐cylodextrin (β‐CD) moiety (PNIPA‐β‐CD) was synthesized by the conjugation of β‐CD carrying amino groups (EDA‐β‐CD) onto PNIPA with epoxy groups (P(NIPA‐co‐GMA), M_n = 3.86 × 10⁴), and the related reaction conditions are investigated. PNIPA‐β‐CD was characterized by means of IR, NMR and UV spectroscopes, element analysis, and differential scanning calorimetry (DSC). The number‐average molecular weight (M_n) and the β‐CD content of the obtained PNIPA‐β‐CD are 4.87 × 10⁴ and 18.8 wt %, respectively. PNIPA‐β‐CD can not only respond to temperature stimuli but also include guest molecules. Lower critical solution temperature (LCST) of aqueous PNIPA‐β‐CD solution is similar to that of PNIPA. The association constant (K_a) for PNIPA‐β‐CD with methyl orange (MO) is 2.4 × 10³ L mol^?1 at pH 1.4, which is comparable to that of EDA‐β‐CD (K_a = 2.9 × 10³ L mol^?1). © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3516–3524, 2005     

Synthesis of a well‐defined polyallene‐based amphiphilic graft copolymer via sequential living coordination polymerization and SET‐LRP

A well‐defined amphiphilic graft copolymer, poly(6‐methyl‐1,2‐heptadien‐4‐ol)‐g‐poly(2‐(dimethylamino)ethyl methacrylate) (PMHDO‐g‐PDMAEMA), has been synthesized by the combination of living coordination polymerization, single electron transfer‐living radical polymerization (SET‐LRP), and the grafting‐from strategy. PMHDO backbone containing double bonds and pendant hydroxyls was first prepared by [(η³‐allyl)NiOCOCF₃]₂‐initiated living coordination polymerization of 6‐methyl‐1,2‐heptadien‐4‐ol (MHDO) followed by treating the pendant hydroxyls with 2‐chloropropionyl chloride to give PMHDO‐Cl macroinitiator. SET‐LRP of 2‐(dimethylamino)ethyl methacrylate (DMAEMA) was performed in THF/H₂O using PMHDO‐Cl as macroinitiator and CuCl/Me₆TREN as catalytic system to afford the well‐defined PMHDO‐g‐PDMAEMA graft copolymer with a narrow molecular weight distribution (M_w/M_n = 1.28). The grafting density was as high as 92%. The critical micelle concentration (cmc) in water was determined by fluorescence probe technique and the micellar morphology was preliminarily explored by transmission electron microscopy. © 2013 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013     

Synthesis of well‐defined AB20‐type star polymers with cyclodextrin‐core by combination of NMP and ATRP

The synthesis of an AB₂₀‐type heteroarm star polymer consisting of a polystyrene arm and 20‐arms of poly(methyl methacrylate) or poly(tert‐butyl acrylate) was carried out using the combination of nitroxide‐mediated polymerization (NMP) and atom transfer radical polymerization (ATRP). The NMP of styrene was carried out using mono‐6‐[4‐(1′‐(2″,2″,6″,6″‐tetramethyl‐1″‐piperidinyloxy)‐ethyl)benzamido]‐β‐cyclodextrin peracetate ( 1 ) to afford end‐functionalized polystyrene with an acetylated β‐cyclodextrin (β‐CyD) unit (prepolymer 2 ) with a number‐average molecular weight (M_n) of 11700 and a polydispersity (M_w/M_n) of 1.17. After deacetylation of prepolymer 2 , the resulting polymer was reacted with 2‐bromoisobutyric anhydride to give end‐functionalized polystyrene with 20(2‐bromoisobutyrol)s β‐CyD, macroinitiator 4 . The copper (I)‐mediated ATRP of methyl methacrylate (MMA) and tert‐butyl acrylate (tBA) was carried out using macroinitiator 4 . The resulting polymers were isolated by SEC fractionation to produce AB₂₀‐type star polymers with a β‐CyD‐core, 5 . The well‐defined structure of 5 with weight‐average molecular weight (M_w)s of 13,500–65,300 and M_w/M_n's of 1.26–1.28 was demonstrated by SEC and light scattering measurements. The arm polymers were separated from 5 by destruction with 28 wt % sodium methoxide in order to analyze the details of their characteristic structure. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 4271–4279, 2005     

Hydroxyl‐terminated hyperbranched aromatic poly(ether‐ester)s: Synthesis,characterization, end‐group modification,and optical properties

Novel AB₂‐type monomers such as 3,5‐bis(4‐methylolphenoxy)benzoic acid ( monomer 1 ), methyl 3,5‐bis(4‐methylolphenoxy) benzoate ( monomer 2 ), and 3,5‐bis(4‐methylolphenoxy)benzoyl chloride ( monomer 3 ) were synthesized. Solution polymerization and melt self‐polycondensation of these monomers yielded hydroxyl‐terminated hyperbranched aromatic poly(ether‐ester)s. The structure of these polymers was established using FTIR and ¹H NMR spectroscopy. The molecular weights (M_w) of the polymers were found to vary from 2.0 × 10³ to 1.49 × 10⁴ depending on the polymerization techniques and the experimental conditions used. Suitable model compounds that mimic exactly the dendritic, linear, and terminal units present in the hyperbranched polymer were synthesized for the calculation of degree of branching (DB) and the values ranged from 52 to 93%. The thermal stability of the polymers was evaluated by thermogravimetric analysis, which showed no virtual weight loss up to 200 °C. The inherent viscosities of the polymers in DMF ranged from 0.010 to 0.120 dL/g. End‐group modification of the hyperbranched polymer was carried out with phenyl isocyanate, 4‐(decyloxy)benzoic acid and methyl red dye. The end‐capping groups were found to change the thermal properties of the polymers such as T_g. The optical properties of hyperbranched polymer and the dye‐capped hyperbranched polymer were investigated using ultraviolet‐absorption and fluorescence spectroscopy. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 5414–5430, 2008     

Chiral sensing of Eu(III)‐containing achiral polymer complex from chiral amino acids coordination induction

The β‐diketonate‐based achiral polymer P‐1 could be synthesized by the polymerization of 3,7‐dibromo‐2,8‐dimethoxy‐5,5‐dioctyl‐5H‐dibenzo[b,d]silole ( M1 ) with (Z)?1,3‐bis(4‐ethynylphenyl)?3‐hydroxyprop‐en‐1‐one ( M2 ) via typical Sonogashira coupling reaction. The β‐diketonate unit in the main chain backbone of P‐1 can further coordinate with Eu(TTA)_x [TTA^? = 4,4,4‐trifluoro‐1‐(thiophen‐2‐yl)butane‐1,3‐dionate anion, X = 1, 2, 3] to afford corresponding Eu(III)‐containing polymer complexes. The resulting achiral polymer complex P‐2 (X = 2) can exhibit strong circular dichroism (CD) response toward both N‐Boc‐l and d‐ proline enantiomers. The CD signal was preliminarily attributed to coordination induction between chiral N‐Boc‐proline and the Eu(III) complex moiety. The linear regression analysis of CD sensing shows a good agreement between the magnitude of molar ellipticity and concentration of chiral N‐Boc‐l or d‐ proline, which indicates this kind Eu(III)‐containing achiral polymer complex can be used as a chiral probe for enantioselective recognition of N‐Boc‐l or d‐ proline enantiomers based on Cotton effect of CD spectra. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 3080–3086     

Organic–inorganic hybrid brushes consisting of macrocyclic oligomeric silsesquioxane and poly(ε‐caprolactone): Synthesis,characterization, and supramolecular inclusion complexation with α‐cyclodextrin

Organic–inorganic hybrid brushes comprised of macrocyclic oligomeric silsesquioxane (MOSS) and poly(ε‐caprolactone) (PCL) were synthesized via the ring‐opening polymerization of ε‐caprolactone (CL) with cis‐hexa[(phenyl) (2‐hydroxyethylthioethyldimethylsiloxy)]cyclohexasiloxane as the initiator. The MOSS macromer bearing hydroxyl groups was synthesized via the thiol‐ene radical addition reaction between cis‐hexa[(phenyl)(vinyldimethylsiloxy)]cyclohexasiloxane and β‐mercaptoethanol. The organic–inorganic PCL cyclic brushes were characterized by means of nuclear magnetic resonance spectroscopy (NMR) and gel permeation chromatography (GPC). These MOSS–PCL brushes were then used to prepare the supramolecular inclusion complexes with α‐cyclodextrin (α‐CD). The X‐ray diffraction (XRD) indicates that the organic–inorganic inclusion complexes (ICs) have a channel‐type crystalline structure. It is noted that the molar ratios of CL unit to α‐CD for the organic–inorganic ICs are quite dependent on the lengths of the PCL chains bonded to the silsesquioxane macrocycle. While the PCL chains were short, the efficiency of inclusion complexation was significantly decreased. The decreased efficiency could be attributed to the repulsion of the adjacent PCL chains bonded to the silsesquioxane macrocycle and the restriction of the bulky silsesquioxane macrocycle on the motion of PCL chains; this effect is pronounced with decreasing the length of the PCL chains. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2009     

Veronicafolin－β-环糊精的物化表征及Veronicafolin－羟丙基-β-环糊精包合物溶解性的增强

用氢谱、红外光谱、X-射线粉末衍射、热分析、元素分析等测试方法研究了Veronicafolin (3,5,4′-三羟基-6,7,3′-三甲氧基黄酮) 和β-环糊精 (β-CD) 的固体包合物的谱学特征。元素分析结果显示形成Veronicafolin-β-CD·20H2O包合物，其中C：39.58%, H: 5.75%，表明包合物中主客体比为1∶1。该包合类型属于A_L-型。通过紫外-可见分光光度法研究了在羟丙基-β-环糊精（HP-β-CD）的存在下Veronicafolin的相溶解度曲线，测得校正曲线为y = 24148x + 0.0075 (r=0.9999)，相溶解曲线为y=0.4738x-2.0×10^-7 (r=0.9490)，包结平衡常数Ks为4.5×10⁶mol-1。HP-β-CD提高了黄酮醇Veronicafolin的溶解度。     

A new linear bismuth coordination polymer based on 1,10‐phenanthroline‐2,9‐dicarboxylic acid: ionothermal synthesis,crystal structure and fluorescence properties

A new linear bismuth(III) coordination polymer, catena‐poly[[chloridobismuth(III)]‐μ₃‐1,10‐phenanthroline‐2,9‐dicarboxylato‐κ⁶O²:O²,N¹,N¹⁰,O⁹:O⁹], [Bi(C₁₄H₆N₂O₄)Cl]_n, has been obtained by an ionothermal method and characterized by elemental analysis, energy‐dispersive X‐ray spectroscopy, IR spectroscopy, thermal stability studies and single‐crystal X‐ray diffraction. The structure is constructed by Bi(C₁₄H₆N₂O₄)Cl fragments in which each Bi^III centre is seven‐coordinated by one Cl atom, four O atoms and two N atoms. The coordination geometry of the Bi^III cation is distorted pentagonal–bipyramidal (BiO₄N₂Cl), with one bridging carboxylate O atom and one Cl atom located in the axial positions. The Bi(C₁₄H₆N₂O₄)Cl fragments are further extended into a one‐dimensional linear polymeric structure via subsequent but different centres of symmetry (bridging carboxylate O atoms). Neighbouring linear chains are assembled via weak C—H...O and C—H...Cl hydrogen bonds, forming a three‐dimensional supramolecular architecture. Intermolecular π–π stacking interactions are observed, with centroid‐to‐centroid distances of 3.678 (4) Å, which further stabilize the structure. In addition, the solid‐state fluorescence properties of the title coordination polymer were investigated.     

Constructing novel double‐bond‐containing well‐defined amphiphilic graft copolymers via successive Ni‐catalyzed living coordination polymerization and SET‐LRP

A series of polyallene‐based well‐defined amphiphilic graft copolymers, poly(6‐methyl‐1,2‐heptadiene‐4‐ol)‐g‐poly(2‐(diethylamino)ethyl methacrylate) (PMHDO‐g‐PDEAEMA), was synthesized through the grafting‐from technique. First, double‐bond‐containing PMHDO backbone bearing pendant hydroxyls was prepared via [(η³‐allyl)NiOCOCF₃]₂‐initiated living coordination polymerization of 6‐methyl‐1,2‐heptadiene‐4‐ol (MHDO). The pendant hydroxyls in the homopolymer were then reacted with 2‐chloropropionyl chloride to give PMHDO‐Cl macroinitiator. Finally, hydrophilic PDEAEMA side chains were formed by single electron transfer‐living radical polymerization (SET‐LRP) of 2‐(diethylamino)ethyl methacrylate (DEAEMA) in THF/H₂O initiated by the macroinitiator using CuCl/Me₆TREN as catalytic system to afford PMHDO‐g‐PDEAEMA graft copolymers. The narrow molecular weight distributions (M_w/M_n ≤ 1.35) and kinetics experiment showed the controllability of SET‐LRP graft copolymerization of DEAEMA. The critical micelle concentration (cmc) of PMHDO‐g‐PDEAEMA amphiphilic graft copolymer in aqueous media was determined by fluorescence probe technique and the relationships between cmc and pH or salinity were also investigated. Micellar morphologies were preliminarily explored using transmission electron microscopy. © 2013 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013     

Self‐Assembly,Spectroscopic and Electrochemical Studies of Nickel(II)‐4,8‐Diazaundecanediamide Complex

The self‐assembly of NiCl₂·6H₂O with a diaminodiamide ligand 4,8‐diazaundecanediamide (L‐2,3,2) gave a [Ni(C₉H₂₀N₄O₂)(Cl)(H₂O)] Cl·2H₂O ( 1 ). The structure of 1 was characterized by single‐crystal X‐ray diffraction analysis. Structural data for 1 indicate that the Ni(II) is coordinated to two tertiary N atoms, two O atoms, one water and one chloride in a distorted octahedral geometry. Crystal data for 1: orthorhombic, space group P 21nb, a = 9.5796(3) Å, b = 12.3463(4) Å, c = 14.6305(5) Å, Z = 4. Through NH···Cl–Ni (H···Cl 2.42 Å, N···Cl 3.24 Å, NH···Cl 158°) and OH···Cl–Ni contacts (H···Cl 2.36 Å, O···Cl 3.08 Å, OH···Cl 143°), each cationic moiety [Ni(C₉H₂₀N₄O₂) (Cl)(H₂O)]⁺ in 1 is linked to neighboring ones, producing a charged hydrogen‐bonded 1D chainlike structure. Thermogrametric analysis of compound 1 is consistent with the crystallographic observations. The electronic absorption spectrum of Ni(L‐2,3,2)²⁺ in aqueous solution shows four absorption bands, which are assigned to the ³A_2g → ³T_2g, ³T_2g → ¹Eg, ³T_2g → ³T_1g, and ³A_2g → ³T_1g transitions of triplet‐ground state, distorted octahedral nickel(II) complex. The cyclic volammetric measurement shows that Ni²⁺ is more easily reduced than Ni(L‐2,3,2)²⁺ in aqueous solution.