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1.
A linear‐shaped polystyrene with C60 core was prepared with a novel initiator system, C60Cln (n average value is 20)/Ni(naph)2/P(Ph)3, and Tp was 130 °C. The results of gel‐permeation chromatography detected by UV detector and fluorescence spectrum of C60‐PSt demonstrated that C60 was chemically bonded to polystyrene. The linear increasing of molecular weights (Mn,GPC) with conversion indicated that this novel initiator system had some characters of living polymerization. A bathochromic shift was found in the UV–vis spectra curves with increasing concentration of C60‐PSt in THF solution. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1215–1218, 2005  相似文献   

2.
C60Cln‐m bonded poly(N‐vinylcarbazole) (C60‐PVK) has been synthesized by C60Cln (the average value of n is 20)/CuCl/ Bpy (2,2′‐bipyridine) catalyst system and its structure was analyzed by UV‐Vis and proton NMR. The polymerization mechanism was proposed proceeding via a atom transfer radical polymerization (ATRP). The block copolymer of poly N‐vinylcarbazole‐block‐polystyrene can also be compounded by adding styrene after N‐vinylcarbazole polymerized completely in this polymerization system. The photoconducting properties of C60Cln‐m‐bonded poly(N‐vinylcarbazole) was better than poly(N‐vinylcarbazole) initiated by AIBN. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 606–609, 2003  相似文献   

3.
Summary C60 bonded poly(N-vinylcarbazole) has been synthesized by C60Cln (the average value of n is 20)/CuCl/2,2'-bipyridine (Bpy) catalyst system and its structure was analyzed by UV-Vis and proton NMR. The polymerization mechanism was proposed proceeding via an atom transfer radical polymerization (ATRP). The photoconducting properties of C60 bonded poly(N-vinylcarbazole) was better than poly(N-vinylcarbazole) initiated by AIBN. Received: 16 October 2001 /Revised version: 8 February 2002/ Accepted: 19 February 2002  相似文献   

4.
Bromo‐Double‐Terminated polystyrene (Br‐PSt‐Br) and poly(methyl methacrylate) (Br‐PMMA‐Br) with predesigned molecular weight and narrow polydispersity were prepared by atom transfer radical polymerization (ATRP) using the initiating system aa′‐dibromo‐p‐xylene(DBX) / CuBr/2,2′‐bipyridine(bipy). The precursor bromo‐terminated polymers were subsequently functionalized with fullerene C60 using CuBr/bipy as the catalyst system under microwave irradiation (MI). The telechelic C60 end‐capped products were characterized by gel permeation chromatography (GPC), UV‐vis, FT‐IR, TGA, DSC, 1H NMR, and 13C NMR. The results showed that microwave irradiation could significantly increase the rate of fullerenation reaction, and the physical properties and structure of the C60 end‐capped polymers are not modified by the use of the microwave. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 828–834, 2006  相似文献   

5.
A crosslinkable terpolymer P(MMA‐BA‐HEMA) was prepared by atom transfer radical copolymerization of 2‐hydroxyethyl methacrylate, methyl methacrylate and butyl acrylate. The structure of the terpolymer was characterized by 1H NMR and gel permeation chromatography. The effects on the polymerization of ligand, initiator, solvent, CuCl2 added in the initial stage and reaction temperature were investigated. The optimal reaction conditions were ethyl 2‐bromopropionate as initiator, CuCl/PMDETA as catalyst, cyclohexanone as solvent, catalyst/ligand = 1:1.5, [M]0:[I]0 = 200:1 and temperature 70 °C. The reaction followed first‐order kinetics with respect to monomer concentration, indicating the best control over the polymerization process, a constant concentration of the propagating radical during the polymerization, efficient control over Mn of the polymer and low polydispersity (Mw/Mn < 1.3). © 2013 Society of Chemical Industry  相似文献   

6.
The synthesis of functionalized fullerene‐C60 (C60) was performed using living anionic polymerization. The metalation of the benzylic hydrogen atom on toluene or p‐substituted toluene was conducted with the alkyllithium/amine system, and examined by living anionic polymerization of 1,3‐cyclohexadiene. The number of carbanions bonded onto C60 was estimated by the grafting reaction of living polymer onto C60. The tert‐butyllithium/N,N,N′,N′‐tetramethylethylenediamine system was an effective metalation reagent, and toluene‐, p‐xylene‐, 4‐methyltriphenylamine‐functionalized C60s having good solubility were successfully synthesized. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

7.
The controlled/living radical polymerization of N‐phenyl maleimide (NPMI) was achieved using 2,2′‐azobisisobutyronitrile as the initiator and 2‐cyanopropyl‐2‐yl dithiobenzoate as the reversible addition‐fragmentation chain transfer agent at 75°C in dichloroethane/ethylene carbonate (60/40, w/w) mixed solvent. The block copolymers of polystyrene‐b‐polyNPMI and poly(n‐butyl methacrylate)‐b‐polyNPMI were successfully prepared by chain extension from dithiobenzoate‐terminated polystyrene and poly (n‐butyl methacrylate) to NPMI, respectively. The obtained NPMI‐based (co)polymers were characterized by gel permeation chromatography and 1H‐NMR spectroscopy. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

8.
The quantitative syntheses of α‐bis and α,ω‐tetrakis tertiary diamine functionalized polymers by atom transfer radical polymerization (ATRP) methods are described. A tertiary diamine functionalized 1,1‐diphenylethylene derivative, 1,1‐bis[(4‐dimethylamino)phenyl]ethylene (1), was evaluated as a unimolecular tertiary diamine functionalized initiator precursor as well as a functionalizing agent in ATRP reactions. The ATRP of styrene, initiated by a new tertiary diamine functionalized initiator adduct (2), affords the corresponding α‐bis(4‐dimethylaminophenyl) functionalized polystyrene (3). The tertiary diamine functionalized initiator adduct (2) was prepared in situ by the reaction of (1‐bromoethyl)benzene with 1,1‐bis[(4‐dimethylamino)phenyl]ethylene (1) in the presence of a copper (I) bromide/2,2′‐bipyridyl catalyst system. The ATRP of styrene proceeded via a controlled free radical polymerization process to afford quantitative yields of the corresponding α‐bis(4‐dimethylaminophenyl) functionalized polystyrene derivative (3) with predictable number‐average molecular weight (Mn) and narrow molecular weight distribution (Mw/Mn) in a high initiator efficiency reaction. The polymerization process was monitored by gas chromatography analysis. Quantitative yields of α,ω‐tetrakis(4‐dimethylaminophenyl) functionalized polystyrene (4) were obtained by a new post ATRP chain end modification reaction of α‐bis(4‐dimethylaminophenyl) functionalized polystyrene (3) with excess 1,1‐bis[(4‐dimethylamino)phenyl]ethylene (1). The tertiary diamine functionalized initiator precursor 1,1‐bis[(4‐dimethylamino)phenyl]ethylene (1) and the different tertiary amine functionalized polymers were characterized by chromatography, spectroscopy and non‐aqueous titration measurements. Copyright © 2012 Society of Chemical Industry  相似文献   

9.
The controllability of the atom transfer radical polymerization of methyl methacrylate in the polar solvent N,N‐dimethylformamide and the nonpolar solvent xylene with 4‐(chloromethyl)phenyltrimethoxysilane as an initiator and with CuCl/2,2′‐bipyridine and CuCl/4,4′‐di(5‐nonyl)‐2,2′‐bipyridine as catalyst systems was studied. Gel permeation chromatography analysis established that in the nonpolar solvent xylene, much better control of the molecular weight and polydispersity of poly(methyl methacrylate) was achieved with the CuCl/4,4′‐di(5‐nonyl)‐2,2′‐bipyridine catalyst system than with the CuCl/2,2′‐bipyridine as catalyst system. In the polar solvent N,N‐dimethylformamide, unlike in xylene, the polymerization was more controllable with the CuCl/2,2′‐bipyridine catalyst system than with the CuCl/4,4′‐di(5‐nonyl)‐2,2′‐bipyridine catalyst system. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 2751–2754, 2007  相似文献   

10.
Poly(n‐butyl methacrylate) (PBMA)‐b‐polystyrene (PSt) diblock copolymers were synthesized by emulsion atom transfer radical polymerization (ATRP). PBMA macroinitiators that contained alkyl bromide end groups were obtained by the emulsion ATRP of n‐butyl methacrylate with BrCH3CHCOOC2H5 as the initiator; these were used to initiate the ATRP of styrene (St). The latter procedure was carried out at 85°C with CuCl/4,4′‐di(5‐nonyl)‐2,2′‐bipyridine as the catalyst and polyoxyethylene(23) lauryl ether as the surfactant. With this technique, PBMA‐b‐PSt diblock copolymers were synthesized. The polymerization was nearly controlled; the ATRP of St from the macroinitiators showed linear increases in number‐average molecular weight with conversion. The block copolymers were characterized with IR spectroscopy, 1H‐NMR, and differential scanning calorimetry. The effects of the molecular weight of the macroinitiators, macroinitiator concentration, catalyst concentration, surfactant concentration, and temperature on the polymerization were also investigated. Thermodynamic data and activation parameters for the ATRP are also reported. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 2123–2129, 2005  相似文献   

11.
In this study a series of novel semifluorinated ABA triblock copolymers with different fluorinated segment lengths and different fluorocarbon side‐chain structures were synthesized via atom transfer radical polymerization (ATRP) and macroinitiator techniques. The macroinitiator, telechelic bromine terminated polystyrene, was obtained from bulk ATRP of styrene with α,α′‐dibromo‐p‐xylene as the initiator and cuprous bromide/α,α′‐bispyridine complex as the catalyst. The polymerization reactions of 2‐[(perfluorononenyl)oxy] ethyl methacrylate and ethylene glycol monomethacrylate monoperfluorooctanoate were initiated by the macroinitiator in the presence of additional catalyst. The characterization of the block copolymers was performed by gel permeation chromatography, 1H‐NMR spectroscopy, and differential scanning calorimetry. The surface activities of the block copolymers in toluene were investigated with the Wilhelmy plate method. The solid surface energy of the block copolymers was determined by measurement of the contact angles. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2625–2633, 2002  相似文献   

12.
Amphiphilic diblock copolymers of polystyrene-b-poly(methacrylic acid) were synthesized by means of atom transfer radical polymerization. First, the polystyrene with a bromine atom at the chain end (PS-Br) was prepared using styrene as the monomer, 1-bromoethyl benzene as the initiator, and CuCl/2,2′-bipyridyl (bpy) as the catalyst ([1-bromoethyl benzene]/[CuCl]/[bpy] = 1:1:3). The polymerization was well controlled. Second, the diblock copolymer of polystyrene-b-poly(tert-butyl methacrylate) was synthesized also by atom transfer radical polymerization using PS-Br as the macro-initiator, CuCl/bpy as the catalyst, and tert-butyl methacrylate (tBMA) as the monomer. Finally, the amphiphilic diblock copolymer, PS-b-PMAA, was obtained by hydrolysis of PS-b-PtBMA under the acid condition. The molecular weight and the structure of aforementioned copolymers were characterized with gel permeation chromatography, infrared, and nuclear magnetic resonance. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 2381–2386, 2001  相似文献   

13.
Pentaerythritol (PT) was converted into four‐arm initiator pentaerythritol tetrakis(2‐chloropropionyl) (PT‐Cl) via reaction with 2‐chloropropionyl chloride. Uniform (monodisperse) star‐polystyrene nanoparticles were prepared by emulsion atom transfer radical polymerization of styrene, using PT‐Cl/CuCl/bpy (bpy is 2,2′‐dipyridyl) as the initiating system. The structures of PT‐Cl and polymer were characterized by Fourier transform infrared spectroscopy and nuclear magnetic resonance. The morphology, size and size distribution of the star‐polystyrene nanoparticles were characterized by transmission electron microscopy, atomic force microscopy and photon correlation spectroscopy. It was found that the average diameters of star‐polystyrene nanoparticles were smaller than 100 nm (30–90 nm) and monodisperse; moreover, the particle size could be controlled by the monomer/initiator ratio and the surfactant concentration. The average hydrodynamic diameter (Dh) of the nanoparticles increased gradually on increasing the ratio of styrene to PT‐Cl and decreased on enhancing the surfactant concentration or increasing the catalyst concentration. Copyright © 2011 Society of Chemical Industry  相似文献   

14.
Copper‐mediated atom transfer radical polymerization (ATRP) of lauryl methacrylate (LMA) and other long‐chain methacrylates was investigated in bulk at 35 °C by using CuCl/N,N,N′,N′,N′′‐pentamethyldiethylenetriamine (PMDETA)/tricaprylylmethylammonium chloride (Aliquat®336) as the catalyst system and ethyl 2‐bromoisobutyrate (EBIB) as the initiator. The investigated monomers can be derived from fatty alcohols and are therefore an important renewable resource for a sustainable development of our future. The amounts of ligand, Aliquat®336 and CuCl were optimized and the effect of their concentrations on the control of the polymerization and the observed conversions were investigated. It was found that a molar ratio of EBIB/CuCl/Ligand/Aliquat®336 of 1 : 1 : 3 : 1 provided the highest conversions of LMA and the best controlled polymerizations. These optimized conditions allowed for the synthesis of poly(lauryl methcarylate)s with different targeted DP (25, 50, 75, 100, 120, 240, and 500), including high‐molecular‐weight polymers with narrow molecular weight distributions. In addition, methacrylate monomers were prepared from fatty alcohols (capric, myristic, palmitic, stearic) and polymerized using the developed procedure to obtain polymers with the same DP and different chain lengths (C10, C12, C14, C16, and C18) of pending alkyl groups. Finally, the thermal properties of these polymers were examined by differential scanning calorimetry and thermogravimetric analysis.  相似文献   

15.
The synthesis of aromatic carboxyl functionalized polymers by atom transfer radical polymerization is described. The α‐bromo‐p‐toluic acid ( 1 ) initiated polymerization of styrene in the presence of copper(I) bromide and 2,2′‐bipyridyl affords quantitative yields of the corresponding aromatic carboxyl functionalized polystyrene ( 2 ). Polymerization proceeded via a controlled free radical process to afford quantitative yields of the corresponding aromatic carboxyl functionalized polymers with predictable molecular weights (Mn = 1600–25 900 g mol−1), narrow molecular weight distribution (Mw /Mn = 1.1–1.40) and an initiator efficiency above 0.87. The polymerization process was monitored by gas chromatographic analysis. The functionalized polymers were characterized by thin layer chromatography, size exclusion chromatography, spectroscopy, potentiometry and elemental analysis. © 2000 Society of Chemical Industry  相似文献   

16.
Photo‐induced atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA) was achieved in poly(ethylene glycol)‐400 with nanosized α‐Fe2O3 as photoinitiator. Well‐defined poly(methyl methacrylate) (PMMA) was synthesized in conjunction with ethyl 2‐bromoisobutyrate (EBiB) as ATRP initiator and FeCl3·6H2O/Triphenylphosphine (PPh3) as complex catalyst. The photo‐induced polymerization of MMA proceeded in a controlled/living fashion. The polymerization followed first‐order kinetics. The obtained PMMA had moderately controlled number‐average molecular weights in accordance with the theoretical number‐average molecular weights, as well as narrow molecular weight distributions (Mw/Mn). In addition, the polymerization could be well controlled by periodic light‐on–off processes. The resulting PMMA was characterized by 1H nuclear magnetic resonance and gel permeation chromatography. The brominated PMMA was used further as macroinitiator in the chain‐extension with MMA to verify the living nature of photo‐induced ATRP of MMA. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42389.  相似文献   

17.
The electrochemical behaviors of a novel class C60 covalently linked PPV derivatives (i.e., PPV‐1‐C60 and PPV‐2‐C60) in thin solid films as well as in solutions are reported. The first cathodic peak potentials of PPV‐1‐C60 and PPV‐2‐C60 have positive shifts by 30 and 50 mV, respectively, compared to pristine C60 in formal cyclic voltammetry (CV). Simultaneous CV and piezoelectric microgravimetry of the drop‐coated thin solid films of PPV‐1‐C60 and PPV‐2‐C60 in acetonitrile solutions of TBA+ counteractions are strongly influenced by the structure of the polymer‐C60, including the length of the chain macromolecule and the steric hindrance effect. In addition, the atomic force microscopy (AFM) images of PPV‐1‐C60 and PPV‐2‐C60 films deposited on Au/quartz electrode both exhibit even distribution. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2737–2741, 2002  相似文献   

18.
Photochemically mediated controlled/“living” polymerization of methyl methacrylate (MMA) triggered by flavone was studied. The polymerization was performed in ethanol at ambient temperature with CuBr2/Tris(2‐dimethylaminoethyl)amine (Me6TREN) as complex catalyst and ethyl 2‐bromoisobutyrate (EBiB) as initiator. The molar mass of poly(methyl methacrylate) (PMMA) was obtained and exhibited relatively narrow molecular weight distribution (Mw/Mn) which was characterized by gel permeation chromatography (GPC). Chain extension further indicated that the living nature was maintained in the photopolymerization system. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43845.  相似文献   

19.
Well‐defined comblike atactic polystyrene functionalized with hydroxyl groups was synthesized via living/controlling radical polymerization promoted by metallocene complexes in the presence of poly(phenyl glycidyl ether)‐co‐formaldehyde as the initiator and Sn as a reducing agent. The effect of the polymerization conditions, such as the ratio of initiator to monomer, temperature, and polymerization time, and the structure of the metallocene complex on the polymerization process were investigated. The resulting polymers were characterized by gel permeation chromatography, multiangle laser light scattering, 1H‐NMR, and 13C‐NMR. The results show that the polymer had a narrow molecular weight distribution in the range 1.1–1.4 and the number‐average molecular weight of the polymer linearly depended on the monomer conversion within the polymerization timescale, which confirmed that living radical polymerization characteristics prevailed in the polymerization process. Both the number of arms and the number of hydroxyl groups in each polymer molecule were about four, which suggested that they arose from the epoxy functional groups of the initiator. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

20.
The degradation of fullerene‐C60 (C60) end‐capped poly(1,3‐cyclohexadiene) (C60‐PCHD) with 2,3‐dichloro‐5,6‐dicyano‐1,4‐benzoquinone (DDQ) was examined to reveal the nature of the covalent carbon–carbon bond between C60 and PCHD (C60‐PCHD bond). The number average molecular weight (Mn) of C60‐PCHD decreased with an increase in the degree of dehydrogenation, and the elimination of a PCHD arm from a C60 occurred. The degradation of the C60‐PCHD bond via a 1,4‐CHD unit was faster than that via a 1,2‐CHD unit, whereas the C60‐poly(cyclohexane) bond was stable. The degradation of the C60‐PCHD bond with DDQ was caused by the dehydrogenation of a CHD unit adjoining a C60 core. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

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