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1.
A new cardo diamine monomer 3, 3‐bis‐[4‐{2′trifluoromethyl 4′‐(4″‐aminophenyl) phenoxy} phenyl]‐2‐phenyl‐2, 3‐dihydro‐isoindole‐1‐one ( 4 ) has been synthesized from potentially cheap phenolphthalein as the starting material. This diamine was used for the synthesis of a new poly(ether amide) and two co‐poly(ether amide)s using 4, 4′‐diaminodiphenyl ether (ODA) as co‐monomer by direct solution polycondensation with 5‐t‐butyl iso‐phthalic acid. These new polymers showed inherent viscosities of 0.48–0.62 dL g?1. The resulting poly(ether amide) and co‐poly(ether amide)s were readily soluble in polar aprotic solvents like NMP, DMF, DMAc, DMSO, and pyridine. The polymers have been fully characterized by 1H and 13C NMR, FTIR spectroscopy, and elemental analysis. These polymers showed glass transition temperatures in the range of 267–310°C. Thermogravimetric analysis indicated high thermal stability of these polymers at 5 and 10% weight loss temperature in air above 357°C and 419°C, respectively. The poly(ether amide) films cast from DMAc were flexible with tensile strength up to 91 MPa, elongations at break up to 11%, and modulus of elasticity up to 1.82 GPa. X‐ray diffraction measurements indicate the amorphous nature of the poly(ether amide)s. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

2.
A new bulky pendent bis(ether anhydride), 1,1‐bis[4‐(4‐dicarboxyphenoxy)phenyl]‐4‐phenylcyclohexane dianhydride, was prepared in three steps, starting from the nitrodisplacement of 1,1‐bis(4‐hydroxyphenyl)‐4‐phenylcyclohexane with 4‐nitrophthalonitrile to form bis(ether dinitrile), followed by alkaline hydrolysis of the bis(ether dinitrile) and subsequent dehydration of the resulting bis(ether diacid). A series of new poly(ether imide)s were prepared from the bis(ether anhydride) with various diamines by a conventional two‐stage synthesis including polyaddition and subsequent chemical cyclodehydration. The resulting poly(ether imide)s had inherent viscosities of 0.50–0.73 dL g?1. The gel permeation chromatography measurements revealed that the polymers had number‐average and weight‐average molecular weights of up to 57,000 and 130,000, respectively. All the polymers showed typical amorphous diffraction patterns. All of the poly(ether imide)s showed excellent solubility in comparison with the other polyimides derived from adamantane, norbornane, cyclododecane, and methanohexahydroindane and were readily dissolved in various solvents such as N‐methyl‐2‐pyrrolidinone, N,N‐dimethylacetamide (DMAc), N,N‐dimethylformamide, pyridine, cyclohexanone, tetrahydrofuran, and even chloroform. These polymers had glass‐transition temperatures of 226–255 °C. Most of the polymers could be dissolved in chloroform in as high as a 30 wt % concentration. Thermogravimetric analysis showed that all polymers were stable up to 450 °C, with 10% weight losses recorded from 458 to 497 °C in nitrogen. These transparent, tough, and flexible polymer films could be obtained by solution casting from DMAc solutions. These polymer films had tensile strengths of 79–103 MPa and tensile moduli of 1.5–2.1 GPa. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2066–2074, 2002  相似文献   

3.
Jiang  Jianwen  Huang  Shuiping  Liu  Yuan  Sheng  Shouri  Huang  Zhenzhong  Song  Caisheng 《中国化学》2010,28(1):102-110
9,9‐Bis(4‐hydroxyphenyl)xanthene (BHPX) was synthesized in 82% yield from xanthenone in a one‐pot, two‐step synthetic procedure. A new diacyl chloride monomer, 9,9‐bis[4‐(chloroformylphenoxy)phenyl]xanthene (BCPX), was synthesized in three steps from the nucleophilic fluorodisplacement of 4‐fluorobenzonitrile with the dipotassium bisphenolate of BHPX, followed by alkaline hydrolysis of the intermediate bis(ether nitrile), and then chlorination with thionyl chloride. Several novel aromatic polyamides containing ether and bulky xanthene groups with the inherent viscosities (0.72–0.98 dL/g) were prepared by the low temperature polycondensation of BCPX with various aromatic diamines in N,N‐dimethylacetamide (DMAc) solution containing pyridine (Py). All new polyamides were amorphous and readily soluble in various polar solvents such as DMAc, N,N‐dimethylformamide (DMF), N‐methyl‐2‐pyrrolidone (NMP) and Py. These polymers showed relatively high glass transition temperatures between 236 and 298°C, decomposition temperatures at 10% weight loss ranging from 490 to 535°C and 483 to 515°C in nitrogen and air, respectively, and char yields at 700°C in nitrogen higher than 50%. Transparent, flexible, and tough films of these polymers cast from DMAc solutions exhibited tensile strengths ranging from 82 to 106 MPa, elongations at break from 10% to 25%, and initial moduli from 2.0 to 2.8 GPa.  相似文献   

4.
A new diamine, 2,2-bis[4-(4-aminophenoxy)phenyl]norbornane (BAPN), containing both ether and norbornane cardo groups, was synthesized in three steps started from norcamphor. A series of cardo polyamides were obtained by the direct polycondensation of BAPN and various aromatic dicarboxylic acids in N-methyl-2-pyrrolidinone (NMP) using triphenyl phosphite and pyridine as condensing agents. Polyamides had inherent viscosities in the range of 0.82–1.58 dL g−1, and were readily soluble in polar aprotic solvents such as NMP, N,N-dimethylacetamide (DMAc) and N,N-dimethylformamide and dimethyl sulfoxide. These polymers were cast in DMAc solution into transparent, flexible, and tough films that were further characterized by X-ray and mechanical analysis. All the polymers were amorphous, and the polyamide films had a tensile strength range of 71–89 MPa, an elongation at break range of 5–9%, and a tensile modulus range of 2.0–2.3 GPa. Polyamides showed glass transition temperatures in the range of 256–296°C as measured by DSC and thermogravimetric analysis indicated no weight loss below 450°C in nitrogen and air atmosphere. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 2791–2794, 1999  相似文献   

5.
A novel aromatic dicarboxylic acid monomer, 4,4′-(2,3-naphthalenedioxy)-dibenzoic acid ( 3 ), was prepared by the fluorodisplacement reaction of p-fluorobenzonitrile with 2,3-dihydroxynaphthalene in N,N-dimethylformamide (DMF) in the presence of potassium carbonate followed by alkaline hydrolysis of the intermediate dinitrile. A series of novel aromatic polyamides containing ortho-linked aromatic units in the main chain were synthesized by the direct polycondensation of diacid 3 and a variety of aromatic diamines using triphenyl phosphite and pyridine as condensing agents in the N-methyl-2-pyrrolidone (NMP) solution containing dissolved calcium chloride. The resulting polyamides had inherent viscosities higher than 0.74 and up to 2.10 dL/g. All of these polyamides were soluble in polar solvents, such as NMP, DMF, N,N-dimethylacetamide (DMAc), and dimethyl sulfoxide. Transparent, flexible, and tough films could be cast from their DMAc or NMP solutions. The solvent-cast films had high tensile strengths and moduli. Extensions to break were relatively low, except for the polymers derived from 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane and 3,4′-oxydianiline, which had elongations of 82 and 62%, respectively. Except for the polyamide based on p-phenylenediamine, all the other polyamides were amorphous in nature. All the polymers are thermally stable to temperatures in excess of 450°C in either air or nitrogen atmosphere. The polymers exhibited glass transition temperatures ranging from 183 to 260°C and decomposition temperatures (10% weight loss) ranging from 462–523°C in air and 468–530°C in nitrogen. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35 : 3385–3391, 1997  相似文献   

6.
程琳  蹇锡高 《中国化学》2000,18(3):414-417
Two novel heterocyclic diamine monomers: 1,2-dihydro-2-(4-aminophenyl)-4-[ 4-( 4-aminophenoxy) phenyl ]-(2H )-phtha-lazin-1-one and 1, 2-dihydro-2-( 4-aminophenyl )-4-[ 4-( 4-aminophenoxy) -3, 5-dimethylphenyl ] - (2H) -phthalazin-1-one were successfully synthesized using readily available heterocyclic bisphenol-like monomers through two steps in high yield. A series of novel poly( aryl ether amide)s containing the phthalazinone moiety with inherent viscosities of 1.16-1.67 dL/g were prepared by the direct polymerization of the novel diamines and aromatic dicarboxylic acids using triphenyl phosphite and pyridine as condensing agents. The polymers were readily soluble in a variety of solvents such as N, N-dimethyl-formamide (DMF), N,N-dimethylacetamide (DMAc), dimethylsulfoxide ( DMSO ), N-methyl-2-pyrrolidinone (NMP), and pyridine. The polymers had high glass transition temperatures (Tg) in the 291-329℃ range.  相似文献   

7.
Poly(arylene ether)s containing N-arylenebenzimidazole groups were prepared by the aromatic nucleophilic displacement reaction of two new bis(hydroxyphenyl-N-arylenebenzimidazole)s with activated aromatic difluorides in sulfolane at 200°C in the presence of anhydrous potassium carbonate. The bis(hydroxyphenyl-N-arylenebenzimidazole)s were prepared from bis(o-aminoanilino) arylenes and phenyl-4-hydroxybenzoate. The polymers were soluble in N-methyl-2-pyrrolidinone and m-cresol and exhibited inherent viscosities from 0.37–0.86 dL/g and glass transition temperatures from 219–289°C. Thermogravimetric analyses showed 5% weight losses from 463–506°C in air and 467–522°C in nitrogen. Unoriented thin films exhibited tensile strengths, moduli, and break elongations at 23°C of 10.2–12.5 ksi, 318–365 ksi, and 4–7%, respectively, and at 177°C of 5.1–6.9 ksi, 256–296 ksi, and 1–5%, respectively. A 50 : 50 random copolymer prepared from 1,3-bis(4-fluorobenzoyl) benzene, 1,1'-(4,4'-biphenylene)-bis[2-(4-hydroxyphenyl)benzimidazole], and 5,5'-bis[2-(4-hydroxyphenyl)benzimidazole] exhibited higher moisture absorption and lower tensile properties than those predicted by a rule of mixtures relationship. The chemical, physical, and mechanical properties of these polymers are discussed. © 1993 John Wiley & Sons, Inc.?  相似文献   

8.
Polyaromatic either-sulfone-ketones containing fluoro-substituted p-cyclophane units were prepared from isophthaloyl chloride, terephthaloyl chloride, diphenyl ether, diphenoxydiphenyl sulfone, and a small amount of 1,1,2,2,9,9,10,10-octafluoro-[2,2]-p-cyclophane (type A) or pseudo-p-1,12,2,9,9,10,10-octafluoro-[2,2]-p-cyclophane bis-acid chloride (type B) by Friedel-Crafts-type polymerization. The p-cyclophane units were incorporated as crosslinking sites. Crosslinking was achieved by curing polymers at 300–350°C for several days. The polymers obtained, containing 1–10 wt % fluoro-substituted p-cyclophane units, were moderately soluble in dichloromethane, DMF, and sulfuric acid with inherent viscosities between 0.4 and 0.6. Laminates on glass fiber were made with excellent thermal stability.  相似文献   

9.
A new bis(ether anhydride), 3,3′,5,5′‐tetramethyl‐2,2‐bis[4‐(4‐dicarboxyphenoxy)phenyl]propane dianhydride ( 3 ), was prepared in three steps: the nitro displacement of 4‐nitrophthalonitrile with 2,2‐bis(4‐hydroxy‐3,5‐dimethylphenyl)propane, the alkaline hydrolysis of the intermediate bis(ether dinitrile), and the subsequent dehydration of the resulting bis(ether diacid). A series of new highly soluble poly(ether imide)s with tetramethyl and isopropylidene groups were prepared from the bis(ether anhydride) 3 with various diamines by a conventional two‐stage synthesis including polyaddition and chemical cyclodehydration. The resulting poly(ether imide)s had inherent viscosities of 0.54–0.73 dL g?1. Gel permeation chromatography measurements revealed that the polymers had number‐average and weight‐average molecular weights of up to 54,000 and 124,000, respectively. All the polymers showed typical amorphous diffraction patterns. All of the poly(ether imide)s showed excellent solubility and were readily dissolved in various solvents such as N‐methyl‐2‐pyrrolidinone, N,N‐dimethylacetamide, N,N‐dimethylformamide, pyridine, cyclohexanone, tetrahydrofuran, and even chloroform. Most of the polymers could be dissolved with chloroform concentrations as high as 30 wt %. These polymers had glass‐transition temperatures of 244–282 °C. Thermogravimetric analysis showed that all polymers were stable, with 10% weight losses recorded above 463 °C in nitrogen. These transparent, tough, and flexible polymer films were obtained through solution casting from N,N‐dimethylacetamide solutions. These polymer films had tensile strengths of 81–102 MPa and tensile moduli of 1.8–2.0 GPa. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2556–2563, 2002  相似文献   

10.
3-(4-Fluorobenzoyl)carbazole was synthesized by a Friedel-Crafts reaction of carbazole with 4-fluorobenzoylchloride. 1H-NMR and MALDI-TOF MS confirmed the structure and the purity. Copolymers of these NH/OH-containing monomers were prepared with 4, 4′-biphenol and bis(4-fluorophenyl)sulfone as comonomers by combined C-O and C-N coupling reactions with activated difluorides. These copolymers were soluble in N-methylpyrrolidinone (NMP), dimethylsulfoxide (DMSO), N,N-dimethylacetamide (DMAc) and dimethylformamide (DMF). The inherent viscosities of the copolymers in NMP solutions at 30°C were all around 0.8 dL/g. They could be easily cast into tough films from NMP solutions. The copolymers exhibited Tgs ranging from 238°C to 282°C. Thermal stabilities by TGA showed no weight loss below 400°C and the temperatures of 5% weight loss ranged from 535°C to 558°C. The homopolymer of 3-(4-fluorobenzoyl)carbazole was insoluble in common solvents and had a Tg of 332°C, and temperature of 5% weight loss of 560°C. UV-VIS absorption and fluorescence of the polymers are also presented.  相似文献   

11.
A series of new strictly alternating aromatic poly(ester‐imide)s having inherent viscosities of 0.20–0.98 dL/g was synthesized by the diphenylchlorophosphate (DPCP) activated direct polycondensation of the preformed imide ring‐containing diacid, 3,3‐bis[4‐(trimellitimidophenoxy)phenyl]phthalide (I), with various bisphenols in a medium consisting of pyridine and lithium chloride. The diimide–diacid I was prepared from the condensation of 3,3‐bis[4‐(4‐aminophenoxy)phenyl]phthalide and trimellitic anhydride. Most of the resulting polymers showed an amorphous nature and were readily soluble in a variety of organic solvents such as N‐methyl‐2‐pyrrolidone (NMP) and N,N‐dimethylacetamide (DMAc). Transparent and flexible films of these polymers could be cast from their DMAc solutions. The cast films had tensile strengths ranging 66–105 MPa, elongations at break from 7–10%, and initial moduli from 1.9–2.4 GPa. The glass‐transition temperatures of these polymers were recorded between 208–275 °C. All polymers showed no significant weight loss below 400 °C in the air or in nitrogen, and the decomposition temperatures at 10% weight loss all occurred above 460 °C. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 1090–1099, 2000  相似文献   

12.
A novel hexamethylspirobichroman (HMSBC) unit-containing dicarboxylic acid, 6,6′-bis(4-carboxyphenoxy)-4,4,4′,4′,7,7′-hexamethyl-2,2′-spirobichroman ( 3 ), was derived from nucleophilic substitution of p-fluorobenzonitrile with the phenolate ion of 6,6′-dihydroxy-4,4,4′,4′,7,7′-hexamethyl-2,2′-spirobichroman ( 1 ), followed by alkaline hydrolysis of the intermediate bis(ether nitrile). Using TPP and pyridine as condensing agents, a series of polyamides with inherent viscosities in the range of 0.82–1.14 dL/g were prepared by the direct polycondensation of dicarboxylic acid 3 with various aromatic diamines. All the obtained polymers were noncrystalline and soluble in various organic solvents such as N,N-dimethylacetamide (DMAc) and N-methyl-2-pyrrolidone (NMP). Except for the polymer derived from benzidine, the other polyamides could be solution cast into transparent and tough films, and their tensile strengths, elongations at break, and tensile moduli were in the range of 56–76 MPa, 4–59%, and 1.6–2.0 GPa, respectively. These polyamides had glass transition temperatures in the range of 183–200°C with 10% weight loss above 420°C. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1479–1486, 1997  相似文献   

13.
This article describes the synthesis and the cation-radical polymerization (Scholl reaction) of 1,3-bis[4-(1-naphthoxy) benzoyl] benzene ( 6 ) and 1,4-bis[4-(1-naphthoxy) benzoyl]- benzene ( 7 ) initiated by FeCI3. This polymerization produced poly(ether ether ketone ketone)s (PEEKK) of number average molecular weight (M?n) up to 5400 g/mol. The synthesis of bis[4-(1-naphthoxy) phenyl] methane ( 8 ), 1,3-bis[4-(1-napthoxy) phenylmethyl] benzene ( 9 ), and 1,4-bis[4-(1-naphthoxy) phenylmethyl] benzene ( 10 ) are also described. Polyethers of M?n up to 15400 g/mol at a FeCl3/monomer molar ratio of 2/1 were obtained. An increased polymerizability of the monomers 9 and 10 containing two CH2 groups versus that of the corresponding monomers containing two carbonyl groups ( 6 and 7 ) was observed. This enhanced polymerizability was explained based on the increased nucleophilicity of monomers 9 and 10 .  相似文献   

14.
The synthesis and the mechanism of oxidative polymerization of 2,2-bis[4-(1-naphthoxy)phenyl]propane ( 4 ) and 2,2-bis[4-(1-naphthyl)phenyl]propane ( 9 ) are presented. Both monomers polymerize by two different propagation steps. The first one represents a cation-radical dimerization of the naphthyl groups to dinaphthyl structure. H+[FeCl4]? generated from the first propagation step initiates a transalkylation reaction which provides structural units containing isopropylidenic groups inserted between phenyl and naphthyl, and between two naphthyl groups, respectively. Since the phenyl groups resulted from the second propagation reaction are unreactive in both the oxidative coupling and the transalkylation steps this polymerization reaction leads to polymers with low molecular weights containing phenyl chain ends.  相似文献   

15.
A series of new poly(ether imide)s containing the naphthalimide moiety were prepared from bis(4-fluorobenzoyl)naphthalimides and several bisphenols by aromatic nucleophilic displacement polymerization. These polyimides had inherent viscosities in the range of 0.31–1.04 dL/g in chloroform and glass transition temperatures of 283.0–341.6°C by differential scanning calorimetry. The onset temperature for 5% weight loss for all the polymers was over 448°C, as assessed by thermogravimetry at a heating rate 10°C/min in nitrogen. In addition, these novel polyimides exhibited good solubility in organic solvents including N-methyl-2-pyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, 1,1,2,2-tetrachloroethane and chloroform. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 3227–3231, 1999  相似文献   

16.
A series of new soluble poly(amide‐imide)s were prepared from the diimide‐dicarboxylic acid 2,2‐bis[4‐(4‐trimellitimidophenoxy)phenyl]hexafluoropropane with various diamines by direct polycondensation in N‐methyl‐2‐pyrrolidinone containing CaCl2 with triphenyl phosphite and pyridine as condensing agents. All the polymers were obtained in quantitative yields with inherent viscosities of 0.52–0.86 dL · g?1. The poly(amide‐imide)s showed an amorphous nature and were readily soluble in various solvents, such as N‐methyl‐2‐pyrrolidinone, N,N‐dimethylacetamide (DMAc), N,N‐dimethylformamide, pyridine, and cyclohexanone. Tough and flexible films were obtained through casting from DMAc solutions. These polymer films had tensile strengths of 71–107 MPa and a tensile modulus range of 1.6–2.7 GPa. The glass‐transition temperatures of the polymers were determined by a differential scanning calorimetry method, and they ranged from 242 to 279 °C. These polymers were fairly stable up to a temperature around or above 400 °C, and they lost 10% of their weight from 480 to 536 °C and 486 to 537 °C in nitrogen and air, respectively. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3498–3504, 2001  相似文献   

17.
《先进技术聚合物》2018,29(8):2204-2215
New aromatic poly(ether ketone amide)s containing 4‐aryl‐2,6‐diphenylpyridine units were prepared by the heterogeneous palladium‐catalyzed carbonylative polymerization of aromatic diiodides with ether ketone units, aromatic diamines bearing pyridine groups, and carbon monoxide. Polymerizations were performed in N,N‐dimethyl‐ acetamide (DMAc) at 120°C in the presence of a magnetic nanoparticles‐supported bidentate phosphine palladium complex [Fe3O4@SiO2‐2P‐PdCl2] as catalyst with 1,8‐diazabicycle[5,4,0]‐7‐undecene (DBU) as base and generated poly(ether ketone amide)s with inherent viscosities up to 0.79 dL/g. All the polymers were soluble in many organic solvents. These polymers showed glass transition temperatures between 219°C and 257°C and 10% weight loss temperatures ranging from 467°C to 508°C in nitrogen. These polyamides could be cast into transparent, flexible, and strong films from DMAc solution with tensile strengths of 86.4 to 113.7 MPa, tensile moduli of 2.34 to 3.19 GPa, and elongations at break of 5.2% to 6.9%. These polymers also exhibited good optical transparency with an ultraviolet‐visible absorption cut‐off wavelength in the 371 to 384‐nm range. Importantly, the new heterogeneous palladium catalyst can easily be recovered from the reaction mixture by simply applying an external magnet and recycled at least 8 times without significant loss of activity. Our catalytic system not only avoids the use of an excess of PPh3 and prevents the formation of palladium black, but also solves the basic problems of palladium catalyst recovery and reuse.  相似文献   

18.
A new adamantane‐based bis(ether anhydride), 2,2‐bis[4‐(3,4‐dicarboxyphenoxy)phenyl]adamantane dianhydride, was prepared in three steps starting from nitrodisplacement of 4‐nitrophthalonitrile with the potassium phenolate of 2,2‐bis(4‐hydroxyphenyl)adamantane. A series of adamantane‐containing poly(ether imide)s were prepared from the adamantane‐based bis(ether anhydride) and aromatic diamines by a conventional two‐stage synthesis in which the poly(ether amic acid)s obtained in the first stage were heated stage‐by‐stage at 150–270°C to give the poly(ether imide)s. The intermediate poly(ether amic acid)s had inherent viscosities between 0.56 and 1.92 dL/g. Except for those from p‐phenylenediamine, m‐phenylenediamine, and benzidine, all the poly(ether amic acid) films could be thermally converted into transparent, flexible, and tough poly(ether imide) films. All the poly(ether imide)s showed limited solubility in organic solvents, although they were amorphous in nature as evidenced by X‐ray diffractograms. Glass transition temperatures of these poly(ether imide)s were recorded in the range of 242–317°C by differential scanning calorimetry and of 270–322°C by dynamic mechanical analysis. They exhibited high resistance to thermal degrdation, with 10% weight loss temperatures being recorded between 514–538°C in nitrogen and 511–527°C in air. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 1619–1628, 1999  相似文献   

19.
Cationic cyclopolymerizations of 2,2‐bis(vinyloxymethyl)bicyclo[2.2.1]heptane ( 1 ), 5,5‐bis(vinyloxymethyl)‐2‐bicyclo[2.2.1]heptene ( 2 ), and 2,2‐bis(vinyloxymethyl)tricyclo[3.3.1.1]3, 7decane ( 3 ), divinyl ethers with a norbornane, norbornene, or adamantane unit, respectively, were investigated with the HCl/ZnCl2 initiating system in toluene and methylene chloride at ?30 °C. All the reactions proceeded quantitatively to give gel‐free, soluble polymers in organic solvents. The number‐average molecular weight (Mn) of the polymers increased in direct proportion to monomer conversion and further increased on addition of a fresh monomer feed to the almost completely polymerized reaction mixture. The contents of the unreacted vinyl groups in the produced soluble polymers were less than ~10 mol %, and therefore, the degree of cyclization of the polymers was determined to be over ~90%. These facts show that cyclopolymerization of 1 , 2 , and 3 exclusively occurred and the poly(vinyl ether)s with the cyclized repeating units and polycyclic pendants were obtained with their molecular weights being regulated. BF3OEt2 initiator also caused cyclopolymerization of 1 , 2 , and 3 to give the corresponding high‐molecular‐weight cyclopolymers quantitatively. Glass transition temperatures (Tg's) of poly( 1 ) and poly( 2 ) were 165–180 °C, and Tg's of poly( 3 ) were 211–231 °C; these values are very high as vinyl ether polymers. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2445–2454  相似文献   

20.
Abstract

A series of poly(ether sulfone)s and poly(ether ketone)s were synthesized from combinations of 1,5- and 2,6-bis(4-fluorosulfonyl)naphthalene, 2,6-bis(4-fluorobenzoyl)naphthalene, and 2,6-bis(4-fluorobenzoyl)quinoline with 3,3′,5,5′-tetramethylbiphenyl-4,4′-diol and 2,2′,3,3′,5,5′-hexamethylbiphenyl-4,4′-diol. The polycondensations proceeded quantitatively in diphenylsulfone in the presence of anhydrous potassium carbonate to afford polymers with inherent viscosities between 0.40 and 1.28 dL/g measured in N-methyl-2-pyrrolidone or concentrated sulfuric acid. The tetramethyl- and hexamethyl-substituted aromatic polyethers exhibited good thermal stability, did not decompose below 330°C in both air and nitrogen atmospheres, and had higher glass transition temperatures than the corresponding unsubstituted polymers. The methylsubstituted poly(ether sulfone)s and poly(ether ketone)s showed good solubility in such common organic solvents as N-methyl-2-pyrrolidone, N,N-dimethylacetamide, tetrahydrofuran, chloroform, and 1,4-dioxane.  相似文献   

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