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1.
The covalent attachment of [60] fullerene (C60) to isotactic polypropylene (i‐PP) is achieved by direct reaction in 1,2,4‐trichlorobenzene (TCB) solution in the presence of dicumyl peroxide (DCP). The chemically modified pendant C60/i‐PP polymers are soluble in chlorinated solvents and have been characterized by ultraviolet–visible and fourier transform infrared spectroscopy, scanning electron microscopy, X‐ray diffraction, differential scanning calorimetry, cyclic voltametry, and thermogravimetric analysis. From the results it can be concluded that the modification of i‐PP by grafting via a free‐radical reaction competes with the possibility of chain scission of i‐PP due to the presence of DCP. The functionalized polymers crystallize in the monoclinic crystal modification, and have high crystallinity. The incorporation of C60 significantly enhances the thermal stability of the i‐PP. Electrochemical measurements demonstrate good electron acceptor properties of the fullerenated i‐PP samples. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 6722–6733, 2008  相似文献   

2.
Enzymatic complexes, constructed by linear‐dendritic copolymers and laccase, are used for the unprecedented one‐pot biotransformation of fullerene (C60) into epoxide‐ and hydroxyl‐derivatives under mild and environmentally friendly reaction conditions (45 °C and aqueous medium). The reaction is catalyzed by mediator pairs ‐ N‐hydroxy‐5‐norbornene‐2,3‐dicarboxylic acid imide/1‐Hydroxybenzotriazole or 2,2′‐Azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid)/1‐Hydroxybenzotriazole used in equimolar amounts. After 24 and 48 h, the biotransformation products ? C60On, C60(OH)n, C60(H)n(OH)n, and/or C60On(H)m(OH)m range between 50 and 78%, respectively. Their structure is revealed by FTIR, NMR, and mass‐spectrometry. The mechanism of the process is discussed and elucidated. The reaction procedure allows the repeated usage of the enzyme/linear‐dendritic complex, which retains its catalytic activity after several cycles. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012  相似文献   

3.
The stereo‐electronic control over bisadditions of conjugated polymers to fullerene (C60) is explored in the formation of alternating copolymers. The chemistry, resulting configuration, and properties of poly(3‐hexylthiophene)‐alt‐C60 copolymers prepared by either classic pyrrolidine ring formation or an atom transfer radical addition are compared. Both routes result in controlled additions of polymers to C60. Extensive macromolecular modeling through PM6 methods indicate that there is no conjugation between P3HT and C60 in the systems studied. This along with 2D‐NMR, AFM, and photovoltaic characterizations of the materials indicate the importance of the structure of the modified C60 and the nature of the linking group between C60 and P3HT segments in determining the morphology of the copolymers in the solid state. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2304–2317, 2009  相似文献   

4.
A star‐shaped poly(1,3‐cyclohexadiene) (PCHD) with a fullerene‐C60 (C60) core (C60‐PCHD) was prepared to examine the thermal stability of the covalent bond between the C60 and PCHD arm in the C60‐PCHD. The covalent bond between the C60 and PCHD arm formed by a 1,2‐cyclohexadiene (CHD) unit on the C60 was stronger than that formed by a 1,4‐CHD unit. The double bond in the CHD unit adjoining the C60 core was a key structure for the stability of that covalent bond. The hydrogenated C60‐PCHD, which did not contain a double bond, possessed significantly higher thermal stability compared to C60‐PCHD. The mechanism of elimination of PCHD arm molecules from the C60 core was thought to proceed via a 1,5‐sigmatropic H‐shift. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2132–2142, 2009  相似文献   

5.
End‐functionalized poly(phenylacetylene)s were synthesized by the polymerization of phenylacetylene (PA) using the well‐defined palladium catalysts represented as [(dppf)PdBr(R)] {dppf = 1,1′‐bis(diphenylphosphino)ferrocene}. The Pd catalysts having a series of R groups such as o‐tolyl, mesityl, C(Ph)?CPh2, C6H4o‐CH2OH, C6H4p‐CN, and C6H4p‐NO2 in conjunction with silver triflate polymerized PA to give end‐functionalized poly(PA)s bearing the corresponding R groups in high yields. The results of IR and NMR spectroscopies and MALDI‐TOF mass analyses proved the introduction of these R groups at one end of each polymer chain. The poly(PA) bearing a hydroxy end group was applied as a macroinitiator to the synthesis of a block copolymer composed of poly(PA) and poly(β‐propiolactone) moieties. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010  相似文献   

6.
Multitopic dibenzylammonium derivatives ( 4 ) of C60 were prepared by Bingel reactions of C60 with a malonate diester ( 2 ) containing two t‐BOC protected dibenzylamine moieties, followed by deprotection and protonation. Self‐assembly of model pseudorotaxanes 5 from the multidibenzylammonium C60 derivatives with dibenzo‐24‐crown‐8 was studied by 1H NMR spectroscopy and mass spectrometry. Self‐assembly of linear and star‐shaped pseudorotaxanes 8 with up to 12 arms based on polystyrenes bearing terminal DB24C8 host units ( 7 ) and the guest functionalized C60 salts was demonstrated by 1H NMR spectroscopy and solution phase viscometry. These studies provide further evidence of the potential of supramacromolecular chemistry in construction of complex polymeric architectures. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6472–6495, 2009  相似文献   

7.
Two new approaches were developed to synthesize C60‐containing polyphosphazenes. Accordingly, two new reactive macromolecular intermediates ( P4 and P8 ) were obtained from poly(dichlorophosphazene) by the direct nucleophilic substitution reaction. In one approach, a predesigned amimo end–functionalized polyphosphazene ( P4 ) was prepared and then reacted with C60 molecules in chlorobenzene to yield C60‐containing polyphosphazene; in the other approach, a polyphosphazene containing 4‐methyl phenoxy groups as side chains was first prepared, and then part of the 4‐methyl groups were converted to azidomethyl groups (in P8 ), which reacted with C60 to yield C60‐containing polyphosphazene. The polymers were characterized by 1H NMR, 13C NMR, IR, and UV–visible spectra and by gel permeation chromatography. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2877–2885, 2004  相似文献   

8.
Water‐soluble diblock copolymer, poly(N‐isopropylacrylamide)‐block‐poly(N‐vinyl‐2‐pyrroridone) (PNIPAMmb‐PNVPn), was found to associate with fullerene (C60), and thus C60 can be solubilized in water. The 63C60/PNIPAMmb‐PNVPn micelle formed a core‐shell micelle‐like aggregate comprising a C60/PNVP hydrophobic core and a thermoresponsive PNIPAM shell. The C60‐containing polymer micelle formation and its thermoresponsive behavior were characterized using light scattering and 1H NMR techniques. The hydrodynamic radius (Rh) of the C60‐bound polymer micelle increased with increasing temperature, which was ascribed to the hydrophobic association between dehydrated PNIPAM shells above lower critical solution temperature (LCST). 1H NMR data suggest that the motion of the PNIPAM block is restricted above LCST due to the dehydration of the PNIPAM shell in water. The generation of singlet oxygen by photosensitization by the C60‐bound polymer micelle was confirmed from photooxidation of 9,10‐anthracenedipropionic acid. Furthermore, DNA was found to be cleaved by visible light irradiation in the presence of the C60‐bound polymer micelle. Therefore, there may be a hope for a pharmaceutical application of the C60‐bound polymer micelle to cancer photodynamic therapy. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011.  相似文献   

9.
A copolymer, poly(aniline‐co‐o‐aminophenol), was prepared chemically by using ammonium peroxydisulfate as an oxidant. The monomer concentration ratio of o‐aminophenol to aniline strongly influences the copolymerization rate and properties of the copolymer. The optimum composition of a mixture for the chemical copolymerization consisted of 0.3 M aniline, 0.021 M o‐aminophenol, 0.42 M ammonium peroxydisulfate, and 2 M H2SO4. The result of cyclic voltammograms in a potential region of ?0.20 to 0.80 V (vs.SCE) indicates that the electrochemical activity of the copolymer prepared under the optimum condition is similar to that of polyaniline in more acid solutions. However, the copolymer still holds the good electrochemical activity until pH 11.0. Therefore, the pH dependence of the electrochemical property of the copolymer is improved, compared with poly(aniline‐co‐o‐aminophenol) prepared electrochemically, and is much better than that of polyaniline. The spectra of IR and 1H NMR confirm that o‐aminophenol units are included in the copolymer chain, which play a key role in extending the usable pH region of the copolymer. The visible spectra of the copolymers show that a high concentration ratio of o‐aminophenol to aniline in a mixture inhibits the chain growth. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5573–5582, 2007  相似文献   

10.
New covalently C60‐conjugated phthalocyanine (Pc) analogues in which the Pc and C60 components are connected by means of a four‐membered ring have been synthesized by taking advantage of a [2+2] cycloaddition reaction of C60 with benzyne units generated from either a phthalocyanine derivative ( 8 ) or its precursor ( 1 ). The reaction of 1 with PhI(OAc)2 and trifluoromethanesulfonic acid (TfOH) followed by the [2+2] cycloaddition of C60 in the presence of tetra‐n‐butylammonium fluoride (TBAF) yielded the C60‐substituted Pc precursor ( 3 ). Mixed condensation of 3 and 4,5‐dibutylsulfonylphthalonitrile ( 4 ) in a thermally promoted template reaction using a nickel salt successfully gave the Pc–C60 conjugate ( 5 ). Results of mass spectrometry and 1H and 13C NMR spectroscopy clearly indicate the formation of the anticipated Pc–C60 conjugate. Direct coupling of C60 with the Pc analogue that contained eight peripheral trimethylsilyl (TMS) groups ( 8 ) also proceeded successfully, such that mono and bis C60‐adducts were detected by their mass, although the isolation of each derivative was difficult. The absorption and magnetic circular dichroism (MCD) spectra of 5 and the reference compound ( 7 ) differ from each other in the Q‐band region, thereby suggesting that the presence of the C60 moiety affects the electronic structure of the conjugate. The reduction and oxidation potentials of 5 and 7 obtained by cyclic voltammetry are comparative, except for the C60‐centered reduction couple at ?1.53 V versus Fc+/Fc in o‐dichlorobenzene (o‐DCB). A one‐electron reduction of 5 and 7 in tetrahydrofuran (THF) by using the sodium mirror technique results in the loss of band intensity in the Q‐band region, whereas the characteristic marker bands for Pc‐ring‐centered reduction appear at around 430, 600, and 900 nm for both compounds. The final spectral shapes of 5 and 7 upon the reduction resemble each other, thus indicating that no significant molecular orbital (MO) interactions between the C60 and Pc units are present for the reduced species of 5 . In contrast, the oxidized species of 5 and 7 generated by the addition of NOBF4 in CH2Cl2 show significantly different absorption spectra from each other. Whereas the broad bands at approximately 400–550 nm of 7 + are indicative of the cationic π‐radical species of metallo‐Pcs and can be assigned to a transition from a low‐lying MO to the half‐filled MO, no corresponding bands were observed for 5 +. These spectral characteristics have been tentatively assigned to the delocalized occupied frontier MOs for 5 +. The experimental results are broadly supported by DFT calculations.  相似文献   

11.
New aluminum alkyl complexes, supported by o‐phenylene‐derived phosphido diphosphine pro‐ligands [Ph‐PPP]‐H and [iPr‐PPP]‐H ([Ph‐PPP]‐H = bis(2‐diphenylphosphinophenyl)phosphine; [iPr‐PPP]‐H = bis(2‐diisopropylphosphinophenyl)phosphine) are reported. Compounds [Ph‐PPP]AlMe2 ( 1 ), [iPr‐PPP]AlMe2 ( 2 ), and [Ph‐PPP]AliBu2 ( 3 ) have been synthesized by reaction of the pro‐ligand with the appropriate trialkyl aluminum precursor and have been characterized by 1H, 13C and 31P NMR spectroscopy. The solution NMR data and theoretical calculations suggest for all complexes trigonal bipyramidal structures with C2v symmetry in which the phosphido diphosphine ligand acts as a κ3 coordinated ligand. All complexes promote the ring‐opening polymerization of ε‐caprolactone, L‐ and rac‐lactide. Polyesters with controlled molecular parameters (Mn, end groups) and low polydispersities are obtained. Upon addition of isopropanol, efficient binary catalytic systems for the immortal ring‐opening polymerization of the cyclic esters are produced. Preliminary investigations show the ability of these complexes to promote copolymerization of l ‐lactide and ?‐caprolactone to achieve copolymers whose microstructures are depending on the structure of the catalyst. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 49–60  相似文献   

12.
Poly(propylene‐ran‐1,3‐butadiene) was synthesized using isospecific zirconocene catalysts and converted to telechelic isotactic polypropylene by metathesis degradation with ethylene. The copolymers obtained with isospecific C2‐symmetric zirconocene catalysts activated with modified methylaluminoxane (MMAO) had 1,4‐inserted butadiene units ( 1,4‐BD ) and 1,2‐inserted units ( 1,2‐BD ) in the isotactic polypropylene chain. The selectivity of butadiene towards 1,4‐BD incorporation was high up to 95% using rac‐dimethylsilylbis(1‐indenyl)zirconium dichloride (Cat‐A)/MMAO. The molar ratio of propylene to butadiene in the feed regulated the number‐average molecular weight (Mn) and the butadiene contents of the polymer produced. Metathesis degradations of the copolymer with ethylene were conducted with a WCI6/SnMe4/propyl acetate catalyst system. The 1H NMR spectra before and after the degradation indicated that the polymers degraded by ethylene had vinyl groups at both chain ends in high selectivity. The analysis of the chain scission products clarified the chain end structures of the poly(propylene‐ran‐1,3‐butadiene). © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5731–5740, 2007  相似文献   

13.
The substitution reaction of poly(vinyl chloride) (PVC) with sodium azide was performed in cyclohexanone. The evolution of unreacted iso‐, hetero‐ and syndiotactic triad contents with the degree of substitution has been followed by 13C NMR spectroscopy. By quantitatively comparing the microstructure changes with degree of substitution, taking into account that the reaction is of SN2 type, only the mechanisms of substitution through the mm triad of mmr tetrad and the rm of rrmr pentads are shown to react. This conclusion was confirmed by FT‐IR. From this stereospecific chemical modification of PVC, the thermal decomposition of azide‐modified PVC and the consequent reaction with styrene offer a method for the preparation of stereoselective graft copolymers. After grafting, no variation of the microstructure of the chain has been demonstrated. These results have been used to study the effect of the aforementioned structures on the evolution of density as a function of free‐volume of the graft copolymers, and thus provide new approaches to a better understanding of the structure‐properties relationships at the molecular level. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 2476–2486, 2006  相似文献   

14.
A new material has been prepared by covalent attachment of a perylene derivative, N‐(carboxyphenyl)‐N′‐(8‐pentadecyl)perylene‐3,4:9,10‐bis(dicarboximide) (PDI‐COOH), to poly(vinyl alcohol) (PVA) by esterification. The perylenediimide (PDI)‐modified PVA polymers are soluble in water and dimethylsulfoxide (DMSO). This solubility is conferred to the insoluble perylene derivative by the water‐soluble polymer. The materials have been characterized by hydrogen‐nuclear magnetic resonance, Fourier transform infrared spectra, X‐ray diffraction, and X‐ray photoelectron spectroscopy confirming the covalent attachment of the PDI to the polymer chains. The significant changes in the crystalline parameters and the thermal stability observed for the polymer after the esterification also confirm the covalent linkage with PDI. In addition, the PDI‐modified PVA shows good fluorescence both in solution (quantum yield ~0.2–0.25) and in solid suggesting that the PDI retains largely its photochemical and photophysical properties after immobilization. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3613–3622, 2010  相似文献   

15.
A novel synthetic strategy was developed to prepare polyphosphazenes containing C60 moieties as side chains. Thus, a new reactive macromolecular intermediate, polyphosphazene azides ( P1 ), was obtained from poly(dichlorophosphazene) by the direct nucleophilic substitution reaction. Then the azide group in P1 reacted with C60 molecules to afford the first example of C60‐containing polyphosphazenes ( P2 and P3 ). The polymers are soluble in common organic solvents. Molecular structural characterization for the polymers was presented by 1H NMR, 13C NMR, IR, ultraviolet–visible spectra, and gel permeation chromatography. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 194–199, 2004  相似文献   

16.
The reactivity of square planar palladium(II) and platinum(II) complexes in trans or cis configuration, namely trans or cis‐[dichlorobis(tributylphosphine)platinum(II)] and trans‐[dichlorobis(tributylphosphine)palladium(II)] with 1,1′‐bis(ethynyl) 4,4′‐biphenyl, DEBP, leading to π‐conjugated organometallic oligomeric and polymeric metallaynes, was investigated by a systematic variation of the reaction conditions. The formation of polymers and oligomers with defined chain length [? M(PBu3)2 (C?C? C6H4? C6H4? C?C? )]n (n = 3–10 for the oligomers, n = 20–50 for the polymers) depends on the configuration of the precursor Pt(II) and Pd(II) complexes, the presence/absence of the catalyst CuI, and the reaction time. A series of model reactions monitored by XPS, GPC, and NMR 31P spectroscopy showed the route to modulate the chain growth. As expected, the nature of the transition metal (Pt or Pd) and the molecular weight of the polymers markedly influence the photophysical characteristics of the polymetallaynes, such as optical absorption and emission behavior. Polymetallaynes with nanostructured morphology could be obtained by a simple casting procedure of polymer solutions. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3311–3329, 2007  相似文献   

17.
This study describes the synthesis and characterization of polymer complexes constructed from the radioprotective agent S‐2(3‐aminopropylamino) ethylphosphorothioic acid dihydrate (amifostine or WR‐2721), applied in the radiation cancer treatment, and biodegradable poly(oxyethylene H‐phosphonate), poly(hydroxyoxyethylene phosphate), or poly(methyloxyethylene phosphate). The immobilization of another radioprotector, used in cancer radiotherapy, 1‐(3‐aminopropyl)aminoethanethiol (WR‐1065) on the same polymers is also achieved through a covalent bond (Atherton‐Todd reaction coupling), ionic bond, and physical complexation, respectively. The structure of the complexes formed is elucidated by 1H‐ 13C‐, 31P NMR and FTIR spectroscopy. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1349–1363, 2007  相似文献   

18.
Highly water soluble [60]fullerene (C60) end‐capped vinyl ether (VE) oligomers with well‐defined structure were synthesized by living cationic polymerization technique. The addition reaction between 1‐octynylfulleride anion and oligomeric cationic species of VEs with pendant acetoxyl or malonic ester functions afforded the precursor C60 end‐capped oligomers. The living VE oligomers were prepared by living cationic polymerization of diethyl 2‐(vinyloxy)ethylmalonate (VOEM) and 2‐acetoxyethyl vinyl ether (AcOVE) by the CH3CH(OR)Cl/ZnI2 [R = CH2CH2OCOCH3 and CH2CH2CH(COOEt)2, respectively] initiating system. The precursors were obtained as dark brown gummy solid in 33 and 72% yield for AcOVE and VOEM, respectively. UV‐vis and 13C NMR spectroscopy indicated the formation of 1,2‐disubstituted dihydrofullerene derivatives. Hydrolysis of the precursors proceeded quantitatively to give the water‐soluble C60 end‐capped oligomers having oligo(sodium 2‐vinyloxyethylmalonate) [oligo(VOEMNa)] and oligo(2‐hydroxyethyl vinyl ether) [oligo(HOVE)] moieties. Solubility measurements revealed the water‐soluble C60 end‐capped oligomer with oligo(VOEMNa) chain to have the excellent aqueous solubility compared to that of the water‐soluble C60 derivatives thus far known; the maximum solubility in water is 96.6 mg/mL, which corresponds to 25.9 mg/mL of the C60 moiety. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 3578–3585, 2000  相似文献   

19.
丁霞  林中祥  邓慧敏 《有机化学》2007,26(2):252-254
拟利用枞酸分子中的非同环共轭二烯在氯化锌作用下异构化成具有同环共轭二烯的海松酸结构, 再与C60进行Diels-Alder加成反应, 预测可以得到Diels-Alder加成产物. C60、枞酸及氯化锌在邻二氯苯溶剂中, 在氮气保护下于175~180 ℃反应8 h, 将反应物洗涤后进行硅胶柱层析分离, 采用FT-IR, 13C NMR, 1H NMR和MALDI-TOF-MS等分析方法对反应主要产物进行结构测定, 却意外发现得到C60与枞酸的加成过程中发生了脱羧脱氢反应且产物含有芳环的化学结构.  相似文献   

20.
本文合成了2种含有烟酸分子修饰的自由卟啉p-(niacin)C2O-TPP和o-(niacin)C2O-TPP及其锌配合物p-(niacin)C2O-TPPZn和o-(niacin)C2O-TPPZn。通过元素分析、紫外-可见光谱、核磁共振氢谱、红外光谱、荧光光谱等多种谱图对结构进行了表征,并结合理论计算搜索了锌卟啉的最低能量构象。同时,利用荧光光谱滴定法测定了这两种金属锌卟啉与咪唑类客体进行轴向配位反应的光谱性质。实验结果表明,(1)金属卟啉p-(niacin)C2O-TPPZn和o-(niacin)C2O-TPPZn中尾式侧链的不同位置对发色团卟啉环的电子云分布造成了不同程度的影响,在溶液中o-(niacin)C2O-TPPZn尾式侧链中的吡啶环与卟啉环之间存在Zn-N间的配位作用;(2)2种锌卟啉与咪唑类客体形成的轴配体系均具有荧光猝灭的性质。  相似文献   

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