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61.
Duygu Sevinc Esen Nese Cakir Yigit Umit Tunca Gurkan Hizal Nergis Arsu 《Journal of polymer science. Part A, Polymer chemistry》2021,59(18):2082-2093
In this study, a new benzoin-based multi-arm star polymer was synthesized by using ATRP, and characterization was achieved by spectrophotometric and chromatographic methods. Obtained multiarm (Benzoin-PS)m-polyDVB star polymer was employed as a polymeric photoinitiator for polymerization of methacrylates and acrylates. Photophysical properties of this initiator were determined by fluorescence and phosphorescence measurements, the phosphorescence lifetime was calculated as 29 ms hence the lowest triplet state nature was n-π* character, and laser flash photolysis technique was additionally used to get more information about triplet state and triplet lifetime which was calculated as 1.34 ms. Photokinetics of difunctional acrylate such as HDDA was studied with a multi-arm (Benzoin-PS)m-polyDVB star polymeric initiator using Photo-DSC. 相似文献
62.
Samanvaya S. Gaur Katelynn J. Edgehouse Aidan Klemm Peiran Wei Burcu Gurkan Emily B. Pentzer 《Journal of polymer science. Part A, Polymer chemistry》2021,59(23):2980-2989
Many ionic liquids (ILs) have good solubilities of CO2 but the high viscosity of ILs makes them cumbersome and kinetically limits gas uptake. Encapsulation of ILs is an effective approach to overcoming these limitations. In capsules with a core of IL, the chemical composition of the shell impacts performance. Here, we report the preparation of capsules with a core of the IL [Bmim][PF6] and polymer composite shell, then evaluate how the identity of the polymer impacts CO2 uptake. IL-in-oil Pickering emulsions stabilized by nanosheets are used, with capsules formed by interfacial polymerization between different diamines and diisocyanates (e.g., shells are polyurea and nanosheets). The capsules contain 60–80 wt% IL and the composition was verified using Fourier transform infrared spectroscopy. Optical microscopy, scanning electron microscopy, and particle sizing data showed spherical, discrete capsules with 50–125 μm in diameter. All capsules are stable up to 250°C. Brunauer–Emmett–Teller analysis of CO2 gas uptake data showed that different polymer compositions led to different CO2 uptake properties, with capacity ranging from 0.065 to 0.025 moles of CO2/kg sorbent at 760 torr and 20°C. This work demonstrates that the polymer identity of the shell impacts gas uptake properties and supports that shell composition can tailor performance. 相似文献
63.
Post‐functionalization of perfluorophenyl ester‐functional acyclic diene metathesis polymer 下载免费PDF全文
Ozgun Daglar Hakan Durmaz Gurkan Hizal Umit Tunca 《Journal of polymer science. Part A, Polymer chemistry》2016,54(16):2593-2598
The acyclic diene metathesis (ADMET) polymerization was utilized for the design of the ADMET polymer (Mn = 21,200 g/mol, Mw/Mn = 1.74) with pendant perfluorophenyl ester functionality using Grubbs first generation catalysis overnight in bulk at 80 °C. Next, a wide variety of functional groups, like benzyl, octyl, propargyl, allyl, and furfuryl was quantitatively incorporated to the ADMET polymer backbone through various amines using activated ester substitution reaction. The ADMET polymers studied in this work were characterized using 1H, 13C, and 19F NMR, GPC and DSC and displayed a monomodal distribution and a rather broad polydispersity index in the range of ?1.33 to 1.90. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 2593–2598 相似文献
64.
Soykan Agar Hakan Durmaz Ufuk Saim Gunay Gurkan Hizal Umit Tunca 《Journal of polymer science. Part A, Polymer chemistry》2015,53(4):521-527
The aliphatic polyurethane with pendant anthracene moieties (PU‐anthracene) was prepared from polycondensation of anthracen‐9‐yl methyl 3‐hydroxy‐2‐(hydroxymethyl)‐2‐methylpropanoate (anthracene diol), 1 with hexamethylenediisocyanate in the presence of dibutyltindilaurate in CH2Cl2 at room temperature for 10 days. Thereafter, the PU‐anthracene (Mn,GPC = 12,900 g/mol, Mw/Mn = 1.87, relative to PS standards) was clicked with a linear α‐furan protected‐maleimide terminated‐poly(methyl methacrylate) (PMMA‐MI) (Mn,GPC = 2500 g/mol, Mw/Mn = 1.33), or ‐poly(ethylene glycol) (PEG‐MI) (Mn,GPC = 550 g/mol, Mw/Mn = 1.09), to result in well‐defined PU‐graft copolymers, PU‐g‐PMMA (Mn,GPC = 23800 g/mol, Mw/Mn = 1.65, relative to PS standards) or PU‐g‐PEG (Mn,GPC = 11,600 g/mol, Mw/Mn = 1.45, relative to PS standards) using Diels–Alder reaction in dioxane/toluene at 105 °C. The Diels–Alder grafting efficiencies were found to be over 93–99% using UV spectroscopy. Moreover, the structural analyses and the thermal transitions of all copolymers were determined via 1H NMR and DSC, respectively. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 521–527 相似文献
65.
Ufuk Saim Gunay Hakan Durmaz Eda Gungor Aydan Dag Gurkan Hizal Umit Tunca 《Journal of polymer science. Part A, Polymer chemistry》2012,50(4):729-735
Well‐defined linear furan‐protected maleimide‐terminated poly(ethylene glycol) (PEG‐MI), tetramethylpiperidine‐1‐oxyl‐terminated poly(ε‐caprolactone) (PCL‐TEMPO), and azide‐terminated polystyrene (PS‐N3) or ‐poly(N‐butyl oxanorbornene imide) (PONB‐N3) were ligated to an orthogonally functionalized core ( 1 ) in a two‐step reaction mode through triple click reactions. In a first step, Diels–Alder click reaction of PEG‐MI with 1 was performed in toluene at 110 °C for 24 h to afford α‐alkyne‐α‐bromide‐terminated PEG (PEG‐alkyne/Br). As a second step, this precursor was subsequently ligated with the PCL‐TEMPO and PS‐N3 or PONB‐N3 in N,N‐dimethylformamide at room temperature for 12 h catalyzed by Cu(0)/Cu(I) through copper‐catalyzed azide‐alkyne cycloaddition and nitroxide radical coupling click reactions, yield resulting ABC miktoarm star polymers in a one‐pot mode. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
66.
Nese Cerit Nese Cakir Aydan Dag Okan Sirkecioglu Hakan Durmaz Gurkan Hizal Umit Tunca 《Journal of polymer science. Part A, Polymer chemistry》2011,49(13):2850-2858
A 2,2,6,6‐tetramethylpiperidine‐1‐oxyl (TEMPO)‐terminated poly(ethylene glycol) (PEG) or ‐poly(ε‐caprolactone) (PCL) (PEG11‐TEMPO or PCL23‐TEMPO) is grafted as a side chain onto a ROMP‐generated polyoxanorbornene (PONB) main backbone with bromide pendant groups (PONB20‐Br) using the NRC click reaction to yield related the brush copolymers, PONB20‐g‐PEG11 or PONB20‐g‐PCL23 catalyzed by Cu(I), Cu(0), and N,N,N′,N″,N″‐pentamethyldiethylenetriamine in N,N‐dimethylformamide at room temperature. Additionally, a ROMP‐generated brush copolymer PONB9‐g‐poly(methyl methacrylate)24 (PMMA)24‐Cl was reacted with a PEG11‐TEMPO or a PCL23‐TEMPO precursor via the NRC click reaction to yield a corresponding brush terpolymer, PONB9‐g‐(PMMA24‐b‐PEG11) or PONB9‐g‐(PMMA24‐b‐PCL23) under a similar reaction condition described above. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
67.
Hakan Durmaz Gurkan Hizal Umit Tunca 《Journal of polymer science. Part A, Polymer chemistry》2011,49(9):1962-1968
Azide‐alkyne and Diels–Alder click reactions together with a click‐like nitroxide radical coupling reaction were used in a one‐pot fashion to generate tetrablock quaterpolymer. The various living polymerization generated linear polymers with orthogonal end‐functionalities, maleimide‐terminated poly(ethylene glycol) (PEG‐MI), anthracene‐ and azide‐terminated polystyrene, alkyne‐ and bromide‐terminated poly(tert‐butyl acrylate) or alkyne‐poly(n‐butyl acrylate), and tetramethylpiperidine‐1‐oxyl (TEMPO)‐terminated poly(ε‐caprolactone) (PCL‐TEMPO) were clicked together in a one‐pot fashion to generate PEG‐b‐PS‐b‐PtBA‐b‐PCL or PEG‐b‐PS‐b‐PnBA‐b‐PCL quaterpolymer using Cu(0), CuBr, and N,N,N′,N″,N″‐pentamethyldiethylenetriamine as catalyst in dimethyl formamide at 80 °C for 36 h. Linear precursors and target quaterpolymers were analyzed via 1H NMR and gel permeation chromatography. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
68.
Ozlem Aldas Candan Hakan Durmaz Gurkan Hizal Umit Tunca 《Journal of polymer science. Part A, Polymer chemistry》2012,50(14):2863-2870
Synthesis of cysteine‐terminated linear polystyrene (PS)‐b‐poly(ε‐caprolactone) (PCL)‐b‐poly(methyl methacrylate) (PMMA)/or poly(tert‐butyl acrylate)(PtBA)‐b‐poly(ethylene glycol) (PEG) copolymers was carried out using sequential quadruple click reactions including thiol‐ene, copper‐catalyzed azide–alkyne cycloaddition (CuAAC), Diels–Alder, and nitroxide radical coupling (NRC) reactions. N‐acetyl‐L ‐cysteine methyl ester was first clicked with α‐allyl‐ω‐azide‐terminated PS via thiol‐ene reaction to create α‐cysteine‐ω‐azide‐terminated PS. Subsequent CuAAC reaction with PCL, followed by the introduction of the PMMA/or PtBA and PEG blocks via Diels–Alder and NRC, respectively, yielded final cysteine‐terminated multiblock copolymers. By 1H NMR spectroscopy, the DPns of the blocks in the final multiblock copolymers were found to be close to those of the related polymer precursors, indicating that highly efficient click reactions occurred for polymer–polymer coupling. Successful quadruple click reactions were also confirmed by gel permeation chromatography. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
69.
Determination of Manganese and Lead in Roadside Soil Samples by FAAS with Ultrasound Assisted Leaching 总被引:1,自引:0,他引:1
An Ultrasonic Leaching Method (ULM) was developed for the analysis of manganese and lead on roadside soil samples in order to assess the pollution from motor vehicle exhaust. The variations in analyte recoveries by sonication periods were investigated and optimum recovery conditions were determined. The leachates of the soil samples, Mn and Pb, were analyzed by flame atomic absorption spectrometry (FAAS). The recoveries of ULM were tested by comparing the results with those of the conventional extraction method (CE) for Mn and Pb. With regard to the dissolution process, higher recoveries were obtained using ULM than with CE in a relatively shorter time. The precision of the method was found to be 1.9–3.7% for Pb and 4.6–8.4% for Mn (n = 4), as the average in terms of relative standard deviation (RSD%) depended on the analyte element concentrations and the nature of the samples. Using the ULM-FAAS method, significant results were obtained for Mn and Pb as vehicle exhaust pollutants. The pollution factors (PFs) obtained for Mn and Pb correlated mainly with vehicle exhaust emissions in different parts of Sivas and partly with some specific environmental conditions.__________From Zhurnal Analiticheskoi Khimii, Vol. 60, No. 5, 2005, pp. 529–535.Original English Text Copyright © 2005 by M. Ozkan, Gurkan, A. Ozkan, Akcay.This article was submitted by the authors in English. 相似文献
70.
Eda Gungor Gulay Cote Tuba Erdogan Hakan Durmaz A. Levent Demirel Gurkan Hizal Umit Tunca 《Journal of polymer science. Part A, Polymer chemistry》2007,45(6):1055-1065
Heteroarm H‐shaped terpolymers, (polystyrene)(poly(methyl methacrylate))‐ poly(tert‐butyl acrylate)‐(polystyrene)(poly(methyl methacrylate)), (PS)(PMMA)‐PtBA‐(PMMA)(PS), and, (PS)(PMMA)‐poly(ethylene glycol)(PEG)‐(PMMA)(PS), through click reaction strategy between PS‐PMMA copolymer (as side chains) with an alkyne functional group at the junction point and diazide end‐functionalized PtBA or PEG (as a main chain). PS‐PMMA with alkyne functional group was prepared by sequential living radical polymerizations such as the nitroxide mediated (NMP) and the metal mediated‐living radical polymerization (ATRP) routes. The obtained H‐shaped polymers were characterized by using 1H‐NMR, GPC, DSC, and AFM measurements. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1055–1065, 2007 相似文献