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1.
A bisphenol bearing pendant maleimide group, namely, N‐maleimidoethyl‐3, 3‐bis(4‐hydroxyphenyl)‐1‐isobenzopyrrolidone (PPH‐MA) was synthesized starting from phenolphthalein. Aromatic (co)polyesters bearing pendant maleimide groups were synthesized from PPH‐MA and aromatic diacid chlorides, namely, isophthaloyl chloride (IPC), terephthaloyl chloride (TPC), and 50:50 mol % mixture of IPC and TPC by low temperature solution polycondensation technique. Copolyesters were also synthesized by polycondensation of different molar proportions of PPH‐MA and bisphenol A with IPC. Inherent viscosities and number‐average molecular weights of aromatic (co)polyesters were in the range of 0.52–0.97 dL/g and 20,200–32,800 g/mol, respectively indicating formation of medium to reasonably high‐molecular‐weight polymers. 13C NMR spectral analysis of copolyesters revealed the formation of random copolymers. The 10% weight loss temperature of (co)polyesters was found in the range 470–484 °C, indicating their good thermal stability. A selected aromatic polyester bearing pendant maleimide groups was chemically modified via thiol‐maleimide Michael addition reaction with two representative thiol compounds, namely, 4‐chlorothiophenol and 1‐adamantanethiol to yield post‐modified polymers in a quantitative manner. Additionally, it was demonstrated that polyester containing pendant maleimide groups could be used to form insoluble crosslinked gel in the presence of a multifunctional thiol crosslinker. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 630–640  相似文献   

2.
Expanding on our strategy to synthesize aromatic step‐growth polymers containing pendant clickable azido groups via functional monomer approach, we have now designed and synthesized a new cardo bisphenol, viz., 2‐(2‐azidoethyl)‐3, 3‐bis(4‐hydroxyphenyl) isoindolin‐1‐one (PPH‐N3). PPH‐N3 was conveniently synthesized starting from commercially available phenolphthalein by a three‐step route in an overall yield of 65% using simple organic transformations. Aromatic (co)polyesters bearing pendant azido groups were synthesized by low‐temperature solution polycondensation of PPH‐N3 or different molar ratios of PPH‐N3 and bisphenol‐A (BPA) with aromatic diacid chlorides in dry dichloromethane in the presence of triethylamine (TEA) as a base. The formation of medium to reasonably high‐molecular‐weight (co)polyesters was evidenced from intrinsic viscosity and number‐average molecular‐weight measurements that were in the range 0.52–0.85 dL/g and 16,700–28,200, respectively. Tough, transparent, and flexible films could be cast from chloroform solutions of these (co)polyesters. (Co)polyesters were characterized using FTIR, 1H NMR, 13C NMR spectroscopy, XRD, and TGA. The thermal curing reaction of (co)polyesters involving decomposition of azido groups was studied by DSC analysis. The chemical modification of a representative copolyester containing pendant azido groups was carried out quantitatively using catalyst‐free azide‐maleimide cycloaddition reaction with two maleimides, namely, N‐methylmaleimide and N‐hexylmaleimide. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1516–1526  相似文献   

3.
Novel polyesters from 2,5‐furandicarboxylic acid or 2,5‐dimethyl‐furandicarboxylate and 2,3‐butanediol have been synthesized via bulk polycondensation catalyzed by titanium (IV) n‐butoxide, tin (IV) ethylhexanoate, or zirconium (IV) butoxide. The polymers were analyzed by size exclusion chromatography, nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy (FTIR), matrix‐assisted laser ionization‐desorption time‐of‐flight mass spectrometry, electrospray ionization time‐of‐flight mass spectrometry, electrospray ionization quadruple time‐of‐flight mass spectroscopy, thermogravimetric analysis, and differential scanning calorimetry. Fully bio‐based polyesters with number average molecular weights ranging from 2 to 7 kg/mol were obtained which can be suitable for coating applications. The analysis of their thermal properties proved that these polyesters are thermally stable up to 270–300 °C, whereas their glass transition temperature (Tg) values were found between 70 and 110 °C. Furthermore, a material was prepared with a molecular weight of 13 kg/mol, with a Tg of 113 °C. This high Tg would make this material possibly suitable for hot‐fill applications. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013  相似文献   

4.
A new cardo diacid chloride, 1,1‐bis‐[4‐(4‐chlorocarboxyphenoxy)phenyl]‐4‐tert‐butylcyclohexane ( 4 ), was synthesized from 1,1‐bis‐[4‐(4‐carboxyphenoxy)phenyl]‐4‐tert‐butylcyclohexane in refluxing thionyl chloride. Subsequently, various new polyesters were prepared from 4 with various bisphenols by solution polycondensation in nitrobenzene using pyridine as a hydrogen chloride quencher at 150 °C. These polyesters were produced with inherent viscosities of 0.32–0.50 dL · g?1. Most of these polyesters exhibited excellent solubility in a variety of solvents such as N,N‐dimethylformamide, tetrahydrofuran, tetrachloroethane, dimethyl sulfoxide, N,N‐dimethylacetamide, N‐methyl‐2‐pyrrolidinone, m‐cresol, o‐chlorophenol, and chloroform. These polymers showed glass‐transition temperatures (Tg's) between 144 and 197 °C. The polymer containing the adamantane group exhibited the highest Tg value. The 10% weight loss temperatures of the polyesters, measured by thermogravimetric analysis, were found to be in the range of 426–451 °C in nitrogen. These cardo polyesters exhibited higher Tg's and better solubility than bisphenol A‐based polyesters. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 2951–2956, 2001  相似文献   

5.
This research aims to produce lignin‐based biodegradable polyesters with improved thermal quality. A series of aliphatic polyesters with lignin‐based aromatic side groups were synthesized by conventional melt‐polycondensation. Decent molecular weight (21–64 kg mol?1) was achieved for the polymerizations. The molecular structures and thermal and mechanical properties of the obtained polyesters were characterized. As a result, the obtained polyesters are all amorphous, and their glass‐transition temperature (Tg) depends on the size of the pendant aromatic group (31–51 °C). Furthermore, according to the TGA results, the thermal decomposition temperatures of the polyesters are all above 390 °C, which make them superior compared with commercial biodegradable polyesters like polylactic acid or polyhydroxyalkanoates. Finally, rheological characteristics and enzymatic degradation of the obtained polyesters were also measured. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 2314–2323  相似文献   

6.
The synthesis and characterization of a new series of aromatic polyesters based on D‐mannitol and galactitol are described. These polyesters were obtained by polycondensation reaction of the terephthaloyl chloride or isophthaloyl chloride and 2,3,4,5‐tetra‐O‐methyl‐D‐mannitol or 2,3,4,5‐tetra‐O‐methyl‐galactitol in o‐dichlorobenzene. All the new polyesters were characterized by elemental analyses, GPC, IR, and NMR. They were soluble in chloroform, but insoluble in water and other polar oxygenated solvents. They showed a notable hygroscopicity, lower for those containing isophthalic units. DSC and X‐ray diffraction studies showed that D‐mannitol‐based polyesters were stiffer and less crystalline than those derived from galactitol, which presented a noticeably lower thermal stability. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 4570–4577, 2005  相似文献   

7.
Biobased, unsaturated polyesters derived from isosorbide, maleic anhydride, and succinic acid were synthesized and characterized. The presence of maleic anhydride units in the structure of the polyesters allowed converting them into cured coatings by radical copolymerization with crosslinking agents such as 2‐hydroxyethyl methacrylate, N‐vinyl‐2‐pyrrolidinone, acrylic acid or methacrylamide. The investigated polyesters were obtained via bulk polycondensation, catalyzed by titanium(IV) n‐butoxide. 2D NMR and MALDI‐Tof‐MS spectroscopy proved that this polymerization resulted in isomerization of maleic acid units into fumaric ones and in the formation of slightly branched structures by the reaction of isosorbide (end) groups with main chain unsaturated bonds. Moreover, some double bonds proved to have reacted with the condensation by‐product water. The resulting polyesters displayed the expected correlation between variables such as molecular weight and content of unsaturated bonds and their Tg values. Since the thermal properties of the obtained polyesters were appropriate for coating applications, the polymers were crosslinked with unsaturated monomers by radical copolymerization. The crosslinking process was studied using FTIR spectroscopy and by measurements of the soluble part of the cured coatings. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 2885–2895, 2010  相似文献   

8.
The synthesis and optical properties of polyesters with pendant fluorinated phenoxy groups were examined. The polyaddition of bisphenol AF diglycidyl ether ( 1 ) with fluorine‐containing terephtalates ( 2a–f ) was carried out with tetrabutylphosphonium chloride (TBPC) as the catalyst in chlorobenzene to afford the corresponding polyesters with number‐average molecular weights (Mn's) ranging from 15,200 to 30,000 in 88–96% yields. Furthermore, the polyaddition of 1 with isophthalate 2g and phthalate 2h also produced high‐molecular‐weight polyesters with Mn's = 22,700 and 22,600 in 88 and 84% yields, respectively. The linear relationship was observed between the fluorine contents and refractive indices of the obtained polyesters. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 213–222, 2003  相似文献   

9.
Copper(I) catalyzed azide‐alkyne 1,3‐Huisgen cycloaddition reaction afforded the synthesis of triazole‐containing polyesters and segmented block copolyesters at moderate temperatures. Triazole‐containing homopolyesters exhibited significantly increased (~40 °C) glass transition temperatures (Tg) relative to high temperature, melt synthesis of polyesters with analogous structures. Quantitative synthesis of azido‐terminated poly(propylene glycol) (PPG) allowed for the preparation of segmented polyesters, which exhibited increased solubility and mechanical ductility relative to triazole‐containing homopolyesters. Differential scanning calorimetry demonstrated a soft segment (SS) Tg near ?60 °C for the segmented polyesters, consistent with microphase separation. Tensile testing revealed Young's moduli ranging from 7 to 133 MPa as a function of hard segment (HS) content, and stress at break values approached 10 MPa for 50 wt % HS segmented click polyesters. Dynamic mechanical analysis demonstrated an increased rubbery plateau modulus with increased HS content, and the Tg's of both the SS and HS did not vary with composition, confirming microphase separation. Atomic force microscopy also indicated microphase separated and semicrystalline morphologies for the segmented click polyesters. This is the first report detailing the preparation of segmented copolyesters using click chemistry for the formation of ductile membranes with excellent thermomechanical response. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012  相似文献   

10.
Polyesters PEs containing high content of fluorene units in their backbones were synthesized from 9,9‐diarene‐substituted fluorene diols ( 1 ) and fluorene‐based diacid chlorides ( 2 ) by high temperature polycondensation at 185 °C in diphenyl ether. The molecular weights of the polyesters PE1‐PE5 were in a range of Mw 25,000–165,000. The polyesters displayed their high thermostability: the glass transition temperatures (Tg) by differential scanning calorimetry analysis ranged from 109 to 217 °C, while the 10% weight loss temperatures (Td10) measured by thermogravimetric analysis were over 400 °C in nitrogen and 395 °C in air. The polyesters had good solubility in most common organic solvents such as chloroform and toluene and gave tough, transparent and flexible cast films. The transmittance of the films was over 80% in the wavelength range from 450 to 700 nm in any PEs . The PEs exhibited high refractive index values around 1.65, while they had very low degree of birefringence. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 2549–2556, 2008  相似文献   

11.

Two series of new unsaturated polyesters were prepared from 2,6‐bis(p‐hydroxidebenzylidene)‐4‐phenylcyclohexanone (I) and 2,6‐divanillyidene‐4‐phenylcyclohexanone (II) with adipoyl, isophthaloyl, sebacoyl and terephthaloyl dichlorides utilizing the interfacial polycondensation technique at ambient temperature. In addition to that, the model compounds were synthesized by reacting (I) and (II) with benzoyl chloride. The model compound and polyester samples have been characterized by elemental and spectral analyses. The unsaturated polyesters have inherent viscosities of 0.96–1.63 dl/g. All the polyesters are amorphous and most of them are partially soluble in most common organic solvents, but easily soluble in concentrated sulfuric acid. Their glass transition temperatures (Tg) range from190.15 to 245.28°C, and the temperatures of 10% weight loss as high as 180 to 220°C in air, indicating that these aromatic polyesters have high Tg and excellent thermal stability.  相似文献   

12.
A new monomer, N,N′‐bis(4‐phenoxybenzoyl)‐p‐phenylenediamine (BPBPPD), was prepared by the condensation of p‐phenylenediamine with 4‐phenoxybenzoyl chloride in N,N‐dimethylacetamide (DMAc). Novel aromatic poly(ether amide amide ether ketone ketone)s (PEAAEKKs) were synthesized by electrophilic Friedel–Crafts solution copolycondensation of BPBPPD with a mixture of terephthaloyl chloride (TPC) and isophthaloyl chloride (IPC), over a wide range of TPC/IPC molar ratios, in the presence of anhydrous aluminum chloride and N‐methylpyrrolidone (NMP) in 1,2‐dichloroethane (DCE). The influences of reaction conditions on the preparation of polymers were examined. The polymers obtained were characterized by different physico–chemical techniques such as FT‐IR, Differential scanning calorimetry (DSC), Thermogravimetric analysis (TGA), and wide angle X‐ray diffraction (WAXD). The polymers with 70–100 mol% IPC are semicrystalline and have remarkably increased Tgs over commercially available poly(ether ether ketone) (PEEK) and poly(ether ketone ketone) (PEKK) due to the incorporation of amide groups in the main chain. The polymers with 70–80 mol% IPC had not only high Tgs of 209–213°C, but also moderate Tms of 339–348°C, which are suitable for melt processing. The polymers with 70–80 mol% IPC had tensile strengths of 107.5–109.8 MPa, Young's moduli of 2.53–2.69 GPa, and elongations at break of 9–11% and exhibited high thermal stability and good resistance to organic solvents. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

13.
Various phase behavior of blends of poly(vinyl ether)s with polyesters of two types (highly crystalline and less crystalline with different main‐chains) were examined using differential scanning calorimetry (DSC) and optical microscopy (OM). Effects of varying the main‐chain polarity of the constituent polyesters on the phase behavior of the blends were analyzed. Miscibility in PVME/polyester blends was found only in polyesters with backbone CH2/CO ratio = 3.5 to 7.0). Tg‐composition relationships for blends of PVME with highly crystalline polyesters (PBA, PHS) were found to differ significantly from those for PVME blends with less‐crystalline polyesters (PTA, PEAz). Crystallinity of highly crystalline polyester constituents in blends caused significant asymmetry in the Tg‐composition relationships, and induced positive deviation of blends' Tg above linearity; on the other hand, blends of PVME with less crystalline polyesters exhibit typical Fox or Gordon‐Taylor types of relationships. The χ parameters for the miscible blends were found to range from ?0.17 to ?0.33, reflecting generally weak interactions. Phase behavior was analyzed and compared among blends of PVME with rapidly crystallizing vs. less‐crystallizing polyesters, respectively. Effects of polyesters' crystallinity and structures on phase behavior of PVME/polyester blends are discussed. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 2899–2911, 2007  相似文献   

14.
Reversible addition‐fragmentation chain transfer (RAFT) polymerization produced novel ABA triblock copolymers with associative urea sites within pendant groups in the external hard blocks. The ABA triblock copolymers served as models to study the influence of pendant hydrogen bonding on polymer physical properties and morphology. The triblock copolymers consisted of a soft central block of poly(di(ethylene glycol) methyl ether methacrylate) (polyDEGMEMA, 58 kg/mol) and hard copolymer external blocks of poly(2‐(3‐hexylureido)ethyl methacrylate‐co‐2‐(3‐phenylureido)ethyl methacrylate) (polyUrMA, 18‐116 kg/mol). Copolymerization of 2‐(3‐hexylureido)ethyl methacrylate (HUrMA) and 2‐(3‐phenylureido)ethyl methacrylate (PhUrMA) imparted tunable hard block Tg's from 69 to 134 °C. Tunable hard block Tg's afforded versatile thermomechanical properties for diverse applications. Dynamic mechanical analysis (DMA) of the triblock copolymers exhibited high modulus plateau regions (∼100 MPa) over a wide temperature range (−10 to 90 °C), which was indicative of microphase separation. Atomic force microscopy (AFM) confirmed surface microphase separation with various morphologies. Variable temperature FTIR (VT‐FTIR) revealed the presence of both monodentate and bidentate hydrogen bonding, and pendant hydrogen bonding remained as an ordered structure to higher than expected temperatures. This study presents a fundamental understanding of the influence of hydrogen bonding on polymer physical properties and reveals the response of pendant urea hydrogen bonding as a function of temperature as compared to main chain polyureas. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56, 1844–1852  相似文献   

15.
A series of novel crosslinkable, highly fluorinated polyesters were synthesized by copolycondensation reactions of terephthaloyl chloride with 4, 4′‐(hexafluoroisopropy‐lidene)‐diphenol and 2,2,3,3,4,4,5,5,6,6,7,7‐dodecafluoro‐octane‐1,8‐diol, followed by reaction with 2‐hydroxyethyl methacrylate. The resulting polyesters with the molecular weights (Mn: 12,100–20,000 g mol?1) and polydispersities (1.49–2.25) were useful for the fabrication of polymer optical devices because of their good solubility in common organic solvent and the processable flexibility. The ratios of the components of the polyesters were characterized by FTIR and NMR. The polyesters had high glass transition temperature (Tg,: up to 170 °C) and good thermal stabilities (Td: up to 470 °C). The refractive index of the polyester film was tuned and controlled in the range of 1.447–1.576 at 1550 nm by monitoring the component fractions during the preparation procedures. Low‐loss optical waveguides were fabricated from the resulting polyesters and the propagation loss of the channel waveguides was measured to be around 0.56 dB/cm at 1550 nm. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5923–5931, 2007  相似文献   

16.
A set of eight functional 4‐vinyl‐1,2,3‐triazolium monomers were synthesized using copper catalyzed azide‐alkyne 2 + 3 Hüisgen cycloaddition. These vinyl‐trizolium monomers readily polymerized via free radical polymerization. The physical properties of the vinyl‐triazolium based poly(ionic liquid)s (PILs) are strongly dependent on the pendant functional groups. These polymers were characterized for glass transition temperature (Tg), solubility, and the thermal decomposition. The vinyl‐triazolium based PILs offer an efficient route to highly functional PILs with the advantage of facile synthesis and the ability to incorporate many desirable functional moieties. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 417–423  相似文献   

17.
A complex pendant with two ethynyl groups, [Fe2(μ‐SCH2CCH)2(CO)6] ( 2 ), as a model of the diiron subunit of [FeFe]‐hydrogenase was polymerized and the {Fe2(CO)6} core was successfully incorporated into the polymer matrix. The polymer was characterized by a variety of spectroscopic techniques, TGA, FTIR, SEM, TEM, and NMR. The resultant polymer was immobilized via “click” chemistry using its terminal C?CH bond onto the surface of a gold electrode, which was premodified with azidothiol by self‐assembled monolayer (SAM). The assembled electrode showed electrochemical responses. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 2410–2417, 2010  相似文献   

18.
A novel aromatic diacid, 3, 5‐dicarboxyl‐4′‐amino diphenyl ether, containing pendant phenoxy amine group was synthesized. Homo‐ and co‐polybenzimidazoles containing different content of pendant phenoxyamine groups were synthesized by condensation of 3,3′‐diaminobenzidine with this acid and a mixture of this acid and isophthalic acid in different ratio in polyphosphoric acid. Copolybenzimidazoles with structural variations were also synthesized based on this acid and pyridine dicarboxylic acid, terephthalic acid, adipic acid, or sebacic acid. The polymers have good solubility in polar aprotic solvents and strong acids and they form tough flexible films by solution casting. The polymers were characterized by different instrumental techniques (FTIR, TGA, DSC, XRD, etc.) and for solvent solubility, mechanical properties, inherent viscosity, and proton conductivity. The inherent viscosities of the polymers vary in the range of 0.62–1.52 dL/g. They have high thermal stability up to 475–506 °C (IDT) in nitrogen, high glass transition temperatures (Tg) ranging from 313 to 435 °C and good tensile strength ranging from 58 to 125 MPa. Proton conductivity of homo polymer is 3.72 × 10?3 S/cm at 25 °C and 2.45 × 10?2 S/cm at 200 °C © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 5776–5793, 2008  相似文献   

19.
A new styrenic monomer 2‐propargyloxy‐5‐vinylbenzaldehyde (PVB) containing both aldehyde and alkyne reactive groups was designed for the synthesis and subsequent orthogonal postfunctionalization of dual‐clickable polymer precursor. Reversible addition‐fragmentation chain transfer polymerization of PVB afforded a structurally well‐defined polymer poly(2‐propargyloxy‐5‐vinylbenzaldehyde) (PPVB) bearing alkyne and aldehyde functionalities that are reactive towards azide ‐ and aminooxy‐containing molecules, respectively. Therefore, the resulting PPVB can be served as a dual‐clickable polymer scaffold for construction of multiple functional polymers via orthogonal alkyne–azide and aldehyde–aminooxy click reactions. Postpolymerization modification of PPVB sequentially with aminooxy‐terminated poly(ethylene oxide)s (H2NO‐PEO) and azide‐functionalized imidazolium‐type ionic liquid (N3‐IL·TFSI, having bis(trifluoromethane)sulfonamide, TFSI, counter‐anion) yielded an interesting multicomponent graft polymer PPVB‐g‐(PEO‐and‐IL·TFSI). After anion exchange of hydrophobic TFSI counter‐anion by bromide (Br) anion, the resulting graft copolymer PPVB‐g‐(PEO‐and‐IL·Br) becomes soluble in water, and its imidazolium units can capture negatively charged tetraphenylethylene disulfonate derivative (TPE‐2 ) guest molecule via electrostatic complexation to form in situ self‐assembled fluorescent nanoaggregates with colloidal stability imparted by hydrophilic PEO chains. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 2650–2656  相似文献   

20.
The biomass‐derived polyesters poly(1,3‐propylene 2,5‐furandicarboxylate) (PPF), poly(1,3‐propylene succinate) (PPS) and poly(1,3‐propylene 2,5‐furandicarboxylate‐co‐1,3‐propylene succinate) (PPFPS) have been synthesized via a two‐step process involving polycondensation and azeotropic distillation. The kinetic parameters were obtained by fitting the experimental data from a batch polymerization reactor to three different kinetic models for polyesterification reactions. The activation energies of the all monomer systems were obtained by Arrhenius plots. Given the increasing availability of biomass‐derived monomers their use in renewable polyesters as substitutes for fossil fuel derived chemicals becomes a distinct possibility. The kinetic modeling of the uncatalyzed polyesterification reactions will enable further integrative process simulation of the studied bioderived polymers and provide a reference for future practical study or industrial applications of catalyzed polyesterification reactions and other bioderived monomer systems. © 2016 The Authors. Journal of Polymer Science Part A: Polymer Chemistry Published by Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 2876–2887  相似文献   

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