共查询到20条相似文献,搜索用时 750 毫秒
1.
Ranjita K. Bose Julia Kötteritzsch Santiago J. Garcia Martin D. Hager Ulrich S. Schubert Sybrand van der Zwaag 《Journal of polymer science. Part A, Polymer chemistry》2014,52(12):1669-1675
In this work, pendant groups with both furan and maleimide moieties were incorporated into a polymethacrylate copolymer with lauryl methacrylate as comonomer to yield a one‐system Diels–Alder (DA) polymer. A combined Fourier transform infrared (FTIR) spectroscopy and rheological study was performed to quantify the extent of the reversible DA reaction and the resulting changes in mechanical properties of the polymer. The kinetics of the retro‐Diels–Alder (rDA) reaction was studied at different temperatures to determine an enthalpy of activation. Control polymers with only one functional moiety, that is, the furan or maleimide, were also synthesized to study the differences in viscoelastic behavior and the absence of self‐healing. Microscratch tests were performed to obtain information about the disappearance of well‐defined intentional surface scratches under different healing conditions. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 1669–1675 相似文献
2.
Tugba Dispinar Rana Sanyal Amitav Sanyal 《Journal of polymer science. Part A, Polymer chemistry》2007,45(20):4545-4551
Polymers containing thiol‐reactive maleimide groups on their side chains have been synthesized by utilization of a novel methacrylate monomer containing a masked maleimide. Diels‐Alder reaction between furan and maleimide was adapted for the protection of the reactive maleimide double bond prior to polymerization. AIBN initiated free radical polymerization was utilized for synthesis of copolymers containing masked maleimide groups. No unmasking of the maleimide group was evident under the polymerization conditions. The maleimide groups in the side chain of the polymers were unmasked into their reactive form by utilization of retro Diels‐Alder reaction. This cycloreversion was monitored by thermo gravimetric analysis (TGA), differential scanning calorimetry (DSC), and 1H and 13C NMR spectroscopy. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4545–4551, 2007 相似文献
3.
Multiarm star polymers with a thermally cleavable core: A “grafting‐from” approach paves the way 下载免费PDF全文
Oyuntuya Munkhbat Ozgul Gok Rana Sanyal Amitav Sanyal 《Journal of polymer science. Part A, Polymer chemistry》2017,55(5):885-893
Thermally cleavable multiarm star polymers containing thermo‐reversible furan–maleimide cycloadduct‐based core were synthesized using dendritic macroinitiators. Peripheries of dendritic macroinitiators were modified with bromine containing free radical initiators to obtain multiarm polymers by utilizing atom transfer radical polymerization (ATRP). Cleavage of thus obtained multiarm polymers was achieved via the retro Diels–Alder cycloreversion reaction of the furan–maleimide core at elevated temperatures. As an alternative approach, combination of multiarm polymers containing a furan and maleimide functional group at their core was attempted to realize that the steric bulk does not allow their formation. Hence the “grafting‐from” route using a thermally fragmentable trigger containing multiarm initiators provides a plausible methodology for fabrication of such thermally cleavable multiarm polymeric materials. Syntheses of dendritic initiators, formation of star polymers as well as their fragmentation were followed by proton nuclear magnetic resonance spectroscopy and size exclusion chromatography. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 885–893 相似文献
4.
Tabito Ikezaki Reishi Matsuoka Kenichi Hatanaka Naoko Yoshie 《Journal of polymer science. Part A, Polymer chemistry》2014,52(2):216-222
We synthesized biobased poly(2,5‐furandimethylene succinate‐co‐butylene succinate) [P(FS‐co‐BS)] copolymers by polycondensation of 2,5‐bis(hydroxymethyl)furan, 1,4‐butanediol, and succinic acid. These copolymers could be crosslinked to form network polymers by means of a reversible Diels–Alder reaction with bis‐maleimide. The thermal properties, mechanical properties, and healing abilities of the P(FS‐co‐BS)s and the network polymers were investigated. The mechanical properties of the network polymers depended on the comonomer composition of the P(FS‐co‐BS)s and the maleimide/furan ratio in the network polymers. Some of the copolymers exhibited healing ability at room temperature, and their healing efficiency was enhanced by solvent or heat. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 216–222 相似文献
5.
Ufuk Saim Gunay Bengu Ozsoy Hakan Durmaz Gurkan Hizal Umit Tunca 《Journal of polymer science. Part A, Polymer chemistry》2013,51(21):4667-4674
We report here a simple and universal synthetic pathway covering triple click reactions, Diels–Alder, copper‐catalyzed azide–alkyne cycloaddition (CuAAC), and nitroxide radical coupling (NRC), to prepare well‐defined graft copolymers with V‐shaped side chains. The Diels–Alder click reaction between the furan protected‐maleimide‐terminated poly(ethylene glycol) (PEG) and a trifunctional core ( 1 ) carrying an anthracene, alkyne, and bromide was carried out to yield the corresponding α‐alkyne‐ and α‐bromide‐terminated PEG (PEG‐alkyne/Br) in toluene at 110 °C. Subsequently, the polystyrene or polyoxanorbornene with pendant azide functionality as a main backbone is reacted with the PEG‐alkyne/Br and 2,2,6,6‐tetramethyl‐1‐piperidinyloxy (TEMPO)‐terminated poly(ε‐caprolactone) using the CuAAC and NRC reactions in a one‐pot fashion in N,N′‐dimethylformamide at room temperature to result in the target V‐shaped graft copolymers. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013 , 51, 4667–4674 相似文献
6.
Hyungwoo Kim Taejin Choi Min Chul Cha Ji Young Chang 《Journal of polymer science. Part A, Polymer chemistry》2013,51(17):3646-3653
A microporous polymer is prepared by a catalyst‐free Diels–Alder reaction. A cyclopentadiene with both a diene and a dienophile functionality and a dienophilic maleimide are used for the Diels–Alder reaction. 1,3,5‐Tris(bromomethyl)‐2,4,6‐trimethylbenzene is reacted with sodium cyclopentadienide to produce the multicyclopentadiene‐functionalized monomer. A crosslinked polymer ( CDAP ) is obtained by the reaction of the cyclopentadiene monomer with N,N′‐1,4‐phenylenedimaleimide. The thermal dissociation of the cyclopentadiene dimeric unit and the subsequent Diels–Alder reaction with the maleimide group are investigated by the model reaction. We are able to restructure the crosslinked polymer network by taking advantage of the thermal reversibility of the Diels–Alder linkage. After the post thermal treatment, the BET surface area of the polymer ( CDAP‐T ) is greatly increased from 317 to 1038 m2 g?1. CDAP‐T is functionalized with pyrene by bromination with N‐bromosuccinimide and the subsequent substitution reaction with aminopyrene. The adsorption property of the pyrene‐functionalized polymer for an aromatic dye is investigated using malachite green. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 3646–3653 相似文献
7.
Hakan Durmaz Aydan Dag Alp Hizal Gurkan Hizal Umit Tunca 《Journal of polymer science. Part A, Polymer chemistry》2008,46(21):7091-7100
3‐Arm star‐block copolymers, (polystyrene‐b‐poly(methyl methacrylate))3, (PS‐b‐PMMA)3, and (polystyrene‐b‐poly(ethylene glycol))3, (PS‐b‐PEG)3, are prepared using double‐click reactions: Huisgen and Diels–Alder, with a one‐pot technique. PS and PMMA blocks with α‐anthracene‐ω‐azide‐ and α‐maleimide‐end‐groups, respectively, are achieved using suitable initiators in ATRP of styrene and MMA, respectively. However, PEG obtained from a commercial source is reacted with 3‐acetyl‐N‐(2‐hydroxyethyl)‐7‐oxabicyclo[2.2.1]hept‐5‐ene‐2‐carboxamide (7) to give furan‐protected maleimide‐end‐functionalized PEG. Finally, PS/PMMA and PS/PEG blocks are linked efficiently with trialkyne functional linking agent 1,1,1‐tris[4‐(2‐propynyloxy)phenyl]‐ethane 2 in the presence of CuBr/N,N,N′,N″,N″‐pentamethyldiethylenetriamine (PMDETA) at 120 °C for 48 h to give two samples of 3‐arm star‐block copolymers. The results of the peak splitting using a Gaussian deconvolution of the obtained GPC traces for (PS‐b‐PMMA)3 and (PS‐b‐PEG)3 displayed that the yields of target 3‐arm star‐block copolymers were found to be 88 and 82%, respectively. © Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7091–7100, 2008 相似文献
8.
Aydan Dag Hakan Durmaz Gurkan Hizal Umit Tunca 《Journal of polymer science. Part A, Polymer chemistry》2008,46(1):302-313
Diels–Alder click reaction was successfully applied for the preparation of 3‐arm star polymers (A3) using furan protected maleimide end‐functionalized polymers and trianthracene functional linking agent (2) at reflux temperature of toluene for 48 h. Well‐defined furan protected maleimide end‐functionalized polymers, poly (ethylene glycol), poly(methyl methacrylate), and poly(tert‐butyl acrylate) were obtained by esterification or atom transfer radical polymerization. Obtained star polymers were characterized via NMR and GPC (refractive index and triple detector detection). Splitting of GPC traces of the resulting polymer mixture notably displayed that Diels–Alder click reaction was a versatile and a reliable route for the preparation of A3 star polymer. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 302–313, 2008 相似文献
9.
《Journal of polymer science. Part A, Polymer chemistry》2018,56(16):1806-1814
A study of the reactions between various furan and maleimide model compounds and the effects of reaction conditions was performed, allowing for a proper design and preparation of a thermo‐reversible polyurethane (PU) material crosslinked via Diels–Alder (DA) bonds. Thus, a linear polyurethane containing furan groups along the main chain was synthesized and crosslinked with a bismaleimide by means of DA reaction. The obtained thermoset exhibited thermo‐reversibility as evidenced by DSC and FTIR microscopy, providing the material recyclability and scratch healability. Optical microscopy, SEM and tensile analysis of a scratched PU film revealed that efficient scratch healing was enabled by heating at 110 °C for 30 min and subsequently keeping at room temperature for 24 h, resulting in an approximately 80% recovery of the pristine mechanical strength. This material is a promising candidate for the development of self‐healing coatings. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56, 1806–1814 相似文献
10.
《Journal of heterocyclic chemistry》2017,54(6):3418-3426
Structurally diverse spiroheterocycles; spiro[pyrimido[2,1‐b ]benzothiazole‐3,3′‐chromene]‐2′,4′‐dione, spiro[pyrimido[2,1‐b ]benzothiazole‐3,5′‐pyrimidine]‐2′,4′,6′‐trione, and spiro[pyrimido[2,1‐b ]benz‐thiazole‐3,2′‐cyclohexane]‐1′,3′‐dione have been synthesized by an environmentally benign, efficient, and facile one‐pot pseudo‐four component reaction of 2‐aminobenzothiazoles with aromatic aldehydes and cyclic β‐diketones in aqueous medium. The process involves hetero‐Diels–Alder cycloaddition and provides facile access to spiroheterocycles fused with potentially interesting biologically active scaffolds. The configuration of hetero‐Diels–Alder cycloadduct has been ascertained through density functional theory calculations. 相似文献
11.
Murat Tonga Nergiz Cengiz Meliha Merve Kose Tuna Dede Amitav Sanyal 《Journal of polymer science. Part A, Polymer chemistry》2010,48(2):410-416
A modular approach toward the synthesis of polymers containing dendron groups as side chains is developed using the Diels–Alder “click” reaction. For this purpose, a styrene‐based polymer appended with anthracene groups as reactive side chains was synthesized. First through third‐generation polyester dendrons containing furan‐protected maleimide groups at their focal point were synthesized. Facile, reagent‐free, thermal Diels–Alder cycloaddition between the anthracene‐containing polymer and latent‐reactive dendrons leads to quantitative functionalization of the polymer chains to afford dendronized polymers. The efficiency of this functionalization step was monitored using 1H and 13C NMR spectroscopy and FTIR and UV–vis spectrometry. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 410–416, 2010 相似文献
12.
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
13.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(9):2368-2373
Herein, a novel methodology for preparing sequence‐controlled polymers is illustrated by using a latent monomer, furan protected maleimide (FMI). At 110 °C, FMI is deprotected by retro Diels–Alder (rDA) reaction, and the released MI is immediately involved in the cross‐polymerization with styrene (St) to deliver heterosegments. At 40 °C the rDA reaction does not proceed, therefore homo‐poly(styrene) segments are produced. By implementing programmable temperature changes during polymerization of St and FMI, “living” polymers with tailored a sequence are created. A ternary copolymerization produces complex sequences as designed. Alkynyl‐functionalized FMI, used as a latent monomer, leads to the desirable placement of functional groups along the polymer chain. This latent‐monomer‐based strategy opens a new avenue for fabricating sequence‐controlled polymers. 相似文献
14.
Hydrogel synthesis by aqueous Diels‐Alder reaction between furan modified methacrylate and polyetheramine‐based bismaleimides 下载免费PDF全文
Clara García‐Astrain Itxaso Algar Alessandro Gandini Arantxa Eceiza María Ángeles Corcuera Nagore Gabilondo 《Journal of polymer science. Part A, Polymer chemistry》2015,53(5):699-708
A simple method for preparing cross‐linked hydrogels in an aqueous medium is investigated using Diels‐Alder (DA) “click” reaction, without employing a catalyst. A polymeric diene is first synthesized by the functionalization of poly(2‐aminoethyl methacrylate) hydrochloride with furfural. Suited bisdienophiles are prepared by modification of Jeffamine® ED of different molecular weights with maleic anhydride. Both precursors of the DA coupling are thoroughly characterized before their reactions. The ensuing hydrogels are analyzed in terms of their microstructure, swelling, and rheological behavior, as a function of the reaction conditions. The influence of the molecular weight of the cross‐linker and the furan‐to‐maleimide ratio on the final properties of the hydrogels were also investigated. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 699–708 相似文献
15.
Marian Vargas Robert M. Kriegel David M. Collard David A. Schiraldi 《Journal of polymer science. Part A, Polymer chemistry》2002,40(19):3256-3263
Dimethyl 2,6‐anthracene dicarboxylate is used as a comonomer in the synthesis of functional copolymers that are subject to modification with Diels–Alder reactions. The formation of poly(ethylene terephthalate‐co‐2,6‐anthracenate), containing less than 20 mol % of the anthracene‐2,6‐dicarboxylate structural units, provides materials that are tractable and soluble. The anthracene units of the copolymers undergo Diels–Alder reactions with N‐substituted maleimides. The grafting of N‐alkylmaleimides affords soluble, hydrophobic polymers, whereas grafting with maleimide‐terminated poly(ethylene glycol) affords hydrophilic polymers. Because this reaction proceeds below the melting point of the copolymers, the procedure can be applied to thin films, whereby the surface properties are modified. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 3256–3263, 2002 相似文献
16.
《Magnetic resonance in chemistry : MRC》2002,40(2):165-167
The Diels–Alder reaction between a thiazole o‐quinodimethane and 4,6‐dichloroquinoline‐5,8‐dione gave 6‐chloro‐9‐azaanthra[2,3‐b]thiazole‐5,10‐dione as a single regioisomer. Its structure was assigned by 2D 1H–13C HMBC short‐ and long‐range correlations. Measuring the spectra in CF3CO2D indicated that both nitrogen atoms of pyridine and thiazole rings are deuterated. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
17.
Facile fabrication of fast recyclable and multiple self‐healing epoxy materials through diels‐alder adduct cross‐linker 下载免费PDF全文
Xiao Kuang Guoming Liu Xia Dong Xianggui Liu Jianjun Xu Dujin Wang 《Journal of polymer science. Part A, Polymer chemistry》2015,53(18):2094-2103
A reversibly cross‐linked epoxy resin with efficient reprocessing and intrinsic self‐healing was prepared from a diamine Diels‐Alder (DA) adduct cross‐linker and a commercial epoxy oligomer. The newly synthesized diamine cross‐linker, comprising a DA adduct of furan and maleimide moieties, can cure epoxy monomer/oligomer with thermal reversibility. The reversible transition between cross‐linked state and linear architecture endows the cured epoxy with rapid recyclability and repeated healability. The reversibly cross‐linked epoxy fundamentally behaves as typical thermosets at ambient conditions yet can be fast reprocessed at elevated temperature like thermoplastics. As a potential reversible adhesive, the epoxy polymer with adhesive strength values about 3 MPa showed full recovery after repeated fracture‐thermal healing processes. The methodology explored in this contribution provides new insights in modification of conventional engineering plastics as functional materials. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 2094–2103 相似文献
18.
Diels‐Alder reaction of 2‐(E‐2‐nitroethenyl)‐1H‐pyrrole ( 2a ) with 1,4‐benzoquinone gave the desired benzo[e]indole‐6, 9(3H)‐dione ( 4a ) in 10% yield versus a 26% yield (lit. 86% [5]) of the known N‐methyl compound ( 4b ) from the N‐(or 1)‐methyl compound ( 2b ). Protection of the nitrogen of 2a with a phenylsul‐fonyl group ( 2c ) gave a 9% yield of the corresponding N‐(or 3)‐phenylsulfonyl compound ( 4c ). The reaction of 2b with 1,4‐naphthoquinone gave in 6% yield (lit. 64% [5]) the known 3‐methylnaphtho[2,3‐e]‐indole‐6, 9(3H)‐dione ( 6 ). The reaction of 2‐(E‐2‐nitroethenyl)furan ( 8a ) gave a small yield of the desired naphtho[2,1‐b]furan‐6, 9‐dione ( 9a ), recognized by comparing its NMR spectrum with that of 4b. The corresponding reaction of 2‐(E‐2‐nitroethenyl)thiophene ( 8b ) gave a 4% yield of naphtho[2,1‐ b ]thiophene‐6,9‐dione ( 9b ), previously prepared in 24% yield [12] in a three‐step procedure involving 2‐ethenylthiophene. Introducing an electron‐releasing 2‐methyl substituent into 8a and 8b gave 12a and 12b , which, upon reaction with 1,4‐benzoquinone, gave 2‐methylnaphtho[2,1‐b]furan‐6, 9‐dione ( 13a ) and its sulfur analog ( 13b ) in yields of 4 and 8%, respectively. 相似文献
19.
Ozgul Gok Sezin Yigit Meliha Merve Kose Rana Sanyal Amitav Sanyal 《Journal of polymer science. Part A, Polymer chemistry》2013,51(15):3191-3201
Diblock and triblock dendron–polymer conjugates containing biodegradable polyester dendron blocks and polyethylene glycol (PEG) polymer were synthesized using the Diels–Alder “click” cycloaddition reaction. PEG polymers with furan‐protected maleimide functionality were synthesized and reacted with biodegradable polyester dendrons containing an anthracene moiety at their focal point. First through third generations of biodegradable polyester dendrons containing an anthracene unit at their focal point were synthesized using a divergent strategy. Efficient conjugation of the dendrons to polymers was demonstrated using 1HNMR and size exclusion chromatography. This modular approach provides an easy access to the design of multivalent PEG conjugates. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 3191–3201 相似文献
20.
Satheesh Chandran M Temina Mary Robert Sunitha K Dona Mathew C. P. Reghunadhan Nair 《先进技术聚合物》2014,25(8):881-890
This paper outlines the synthesis and characterization of O‐allyl aralkyl phenolic (O‐allyl Xylok, OAX) resins having low melt viscosity and its Alder‐ene blends with 2, 2′‐bis 4‐[(4′‐maleimido phenoxy) phenyl] propane. The blends manifested a three‐stage curing pattern that converged to a two‐stage pattern on enhancing the maleimide content. The polymerization kinetics of typical allyl and maleimide rich resin systems showed apparent activation energy increasing and pre‐exponential factor decreasing from ene to the Diels–Alder step. Increased allyl content improved mechanical and impact properties of the composites at ambient temperature, although it diminished the retention of interlaminar shear strength at elevated temperature. Increased maleimide content of the resin was conducive for the higher rigidity for the composite and its retention at elevated temperature. A substantial increase in Tg (from 153°C to 280°C) and thermal stability was observed with an increase in maleimide content. High allyl content resulted in improved mechanical properties thanks to better resin–reinforcement interaction as revealed from morphological analysis. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献