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1.
A series of new AB-type poly(etherimide)s having bisphenol-type moiety was prepared by the one-pot polyimidization using triphenylphosphite(TPP) in N-methyl-2-pyrrolidone(NMP)/pyridine solution at 150°C. Complete cyclodehydration was observed in the polymerizations as well as in model reactions. Polymers were obtained with inherent viscosities in the 0.27–0.49 dL/g range. The Mn and Mw/Mn of poly[4-(1,4-phenyleneoxy-1,4-phenylenehexafluoro-isopropylidene-1,4-phenylene)oxyphthalimide] (4d) with ηinh = 0.49 dL/g were 73,400 g/mol and 1.5, respectively. Most polymers could readily be dissolved in common organic solvents such as DMAc, NMP, and m-cresol. The polymer 4d was soluble even in chloroform. These polymers had glass transition temperatures between 205 and 235°C, and 5% weight loss temperatures in the range of 511–532°C in nitrogen. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 3530–3536, 1999  相似文献   

2.
A series of new poly(arylene ether)s, containing naphthalene, pyridine, and quinoline units have been prepared by solution condensation polymerization. The synthesis involves nucleophilic displacement of aromatic dihalides with aromatic potassium bisphenates in an anhydrous dipolar aprotic solvent at elevated temperatures. The polymers, having inherent viscosity from 0.24 to 1.32 dL/g, were obtained in quantitative yield, have excellent thermal stability as shown by 10% weight loss temperatures in nitrogen and air (above 450 and 430°C, respectively) and high glass transition temperatures (in the range of 150–220°C). The introduction of quinoline moieties in the polymer backbone positively influences the thermal properties, such as high Tg/Tm ratios. © 1995 John Wiley & Sons, Inc.  相似文献   

3.
New thioether- and thianthrene-containing poly(benzoxazole)s (PBOs) were synthesized from 4,4′-thiobis[3-chlorobenzoic acid] and thianthrene-2,7- and -2,8-dicarbonyl chlorides with commercially available bis-o-aminophenols. Polymers were prepared via solution polycondensation in poly(phosphoric acid) at 90–200°C. Transparent PBO films were cast directly from polymerization mixtures or m-cresol. The films were flexible and tough. Non-fluorinated PBOs were soluble only in strong acids and AlCl3/NO2R systems by forming complexes with the benzoxazole heterocycle Glass transition temperatures ranged from 298–450°C, and thermogravimetric analysis showed good thermal stabilities in both air and nitrogen atmospheres. © 1995 John Wiley & Sons, Inc.  相似文献   

4.
Poly (aryl ether)s containing the diphenylethylene moiety, synthesized from 1,1-bis(4-fluo-rophenyl)ethylene or 1,1-bis(4-hydroxyphenyl)ethylene, are thermally crosslinkable. Char-acterization and crosslinking studies of these polymers were carried out by GPC, DSC, TGA, and NMR. The solvent resistance and Tg's of the resulting crosslinked networks increase after crosslinking. Thermogravimetric analysis shows that no significant mass loss accompanies the crosslinking reaction. © 1995 John Wiley & Sons, Inc.  相似文献   

5.
A series of new poly(aryl ether)s containing the pyrimidine moiety were prepared by a nucleophilic aromatic substitution polymerization reaction in an aprotic solvent (DMAc) in the presence of excess potassium carbonate. These polymers are high molecular weight, amorphous, and soluble in common solvents at room temperature. The polymers are easily cast from solution into flexible, colorless, and transparent films. They showed high glass transition temperatures ranging from 198 to 304°C by DSC analysis. The 5% weight losses by thermogravimetric analysis ranged from 478 to 580°C, indicating that these polymers are very thermostable in nitrogen and air. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1107–1110, 1998  相似文献   

6.
Two poly(aryl ether)s containing naphthyl moieties were prepared from bis(3,5-dimethyl-4-hydroxyphenyl)naphthyl methane (monomer 1) via nucleophilic aromatic substitution polycondensation with bis(4-fluorophenyl) ketone and bis(4-fluorophenyl) sulfone.The structures of these polymers were confirmed by ~1H NMR.The M_n values of the two polymers were 96,200 and 88,600, respectively.The polymers exhibited good thermal stabilities with 5%mass loss at T>400℃and high glass-transition temperature(T_g) of T>250℃...  相似文献   

7.
8.
Novel poly(arylene ether)s with sulfonic acid containing pendent groups were successfully synthesized by the nucleophilic displacement of aromatic dihalides with bisphenols in an aprotic solvent in the presence of excess potassium carbonate followed by sulfonation with chlorosulfonic acid. The sulfonation took place only at the controlled positions on the phenyl rings due to the novel bisphenol structures designed. The sulfonic acid group containing polymers were very soluble in common organic solvents, such as dimethyl sulfoxide, N,N′‐dimethylacetamide, and dimethylformamide, but swelled only slightly in water. These sulfonic acid group containing polymers were readily cast into tough and smooth films from organic solvents. The synthesized polymers had high glass‐transition temperatures of 171.0–240.7 °C and high molecular weights of 15,600–33,000 Da. These films could potentially be used as proton‐exchange membranes for fuel cells. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 1779–1788, 2004  相似文献   

9.
A series of novel poly(ether ketone ketone)s (PEKKs) were synthesized from diphenyl ether and isophthaloyl chloride derivatives such as 5‐halo‐ and 5‐tert‐butyl‐isophthaloyl chloride. The aromatic electrophilic substitution route to polyketones was a convenient route for the preparation of the polymers in high yields via precipitation polycondensation at a low temperature with aluminum trichloride as a catalyst. High molecular weight PEKKs were achieved with number‐average molecular weights of 15,000–100,000 g/mol for polymers that showed good solubility in organic solvents. The presence of substituents greatly modified the spectroscopic features in comparison with those of unsubstituted isophthaloyl poly(ether ketone ketone)s, particularly for the series containing halogens, for which significant variations of the chemical shifts in both 1H and 13C NMR spectra were observed; these shifts could be related to the nature of the halogen. Thermal properties were also affected by the presence of pendent substituents, with clear enhancements of the glass‐transition temperatures, which could be ascribed to the nature and bulkiness of the substituents. Thermogravimetric analyses showed that the new polymers had good thermal resistance, although an important drop in thermal resistance was observed for polymers bearing large halogen atoms, such as bromine and iodine. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2601–2608, 2002  相似文献   

10.
A series of novel soluble poly(amide-imide)s were prepared from the diimide-dicarboxylic acid, 2,2-bis[N-(4-carboxyphenyl)-phthalimidyl]hexafluoropropane, with various diamines by the direct polycondensation in N-methyl-2-pyrrolidinone containing CaCl2 using triphenyl phosphite and pyridine as condensing agents. All the polymers were obtained in quantitative yields with inherent viscosities of 0.78–1.63 dL g−1. The polymers were amorphous and readily soluble in aprotic polar solvents such as N-methyl-2-pyrrolidinone, N,N-dimethylacetamide, N,N-dimethylformamide, and dimethyl sulfoxide as well as in less polar solvents such as pyridine and γ-butyrolactone, and also in tetrahydrofuran. The polymer films had tensile strength of 84–129 MPa, an elongation at break range of 6–22%, and a tensile modulus range of 2.0–2.7 GPa. The glass transition temperatures of the polymers were determined by DSC method and they were in the range of 240–282°C. These polymers were fairly stable up to a temperature around or above 400°C, and lose 10% weight in the range of 450–514°C and 440–506°C in nitrogen and air, respectively. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 2629–2635, 1999  相似文献   

11.
The synthesis and structural characterization of a series of novel, fluorinated poly(phthalazinone ether)s containing perfluorophenylene moieties are described. The monomers, 4‐(4′‐hydroxyaryl)phthalazin‐1(2H)‐ones ( 2a – 2d ), were conveniently and efficiently synthesized from phenols and phthalic anhydride in two steps via 2‐(4′‐hydroxybenzoyl)benzoic acids, which were first obtained by the Friedel–Crafts reaction in good yields and with high stereoselectivity and were then converted into 2a – 2d by fusion with hydrazine. All the polymers were prepared by nucleophilic aromatic substitution (SNAr) polycondensation between the compounds perfluorobiphenyl and 4‐(4′‐hydroxyaryl)phthalazin‐1(2H)‐ones ( 2a ‐ 2d ). The resulting fluorinated polymers were readily soluble in common organic solvents (e.g., CHCl3, tetrahydrofuran, dimethylformamide, dimethyl sulfoxide, N‐methylpyrrolidone, etc.) at room temperature. Their weight‐average molecular weights and the polydispersities ranged from (7.96–18.25) × 103 to 1.31–2.71, respectively. Their glass‐transition temperatures varied from 213 to 263 °C. They were all stable up to 390 °C both in air and in argon. The 5% weight‐loss temperatures of these polymers in air and argon ranged from 393–487 to 437–509 °C, respectively. Wide‐angle X‐ray diffraction studies indicated they were all amorphous and could be attributed to the presence of kink nonplanar moiety, phenyl phthalazinone along the polymer backbone. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 925–932, 2004  相似文献   

12.
A series of aliphatic poly(ester amide)s derived from 1,6-hexanediol, glycine, and diacids with a variable number of methylenes (from 2 to 8) have been synthesized and characterized. Infrared spectroscopy shows that the studied polymers present a unique kind of hydrogen bond that is established between their amide groups. Thermal properties as melting, glass transition, and decomposition temperatures are reported. The data indicate that all the polymers are highly crystalline. Thus, different kinds of spherulites (positive and/or negative) were obtained depending on the preparation conditions and on the polymer samples. Moreover, all the polymers crystallized from dilute diol solutions as ribbonlike crystals where a regular folding habit and a single hydrogen bond direction could be deduced. A test of enzymatic hydrolysis was employed to assess the potential biodegradability of these polymers. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1271–1282, 1998  相似文献   

13.
A series of poly(arylene ether)s containing triphenylmethane moiety were synthesized by the nucleophilic displacement of aromatic dihalides with bisphenols in an aprotic solvent in the presence of excess potassium carbonate. High molecular weight and fibrous polymers in white color can be readily afforded in short reaction time. The structures of the synthesized monomers and polymers were investigated by 1H NMR and MS techniques. The sulfonation position of the synthesized polymer can be easily controlled and the water-up-take can be conveniently tailored by changing the amount of sulfonation agent. This sulfonated polymer 4b is soluble in polar organic solvents, such as NMP, DMAc, DMSO, DMF, ethylene glycol monomethyl ether, and can be readily cast into tough and smooth films from solutions. The sulfonated polymers can be potentially used as the proton-exchange membranes for fuel-cells.  相似文献   

14.
The preparation of poly(4-oxy-1,4-phenylenesulfonyl-4,4′-biphenylene-4-sulfonylphenylene) (PBP) has been accomplished by the base mediated, polycondensation reaction between two biphenyl containing monomers. The bisphenol, 4,4′-bis[(4-hydroxyphenyl) sulfonyl]biphenyl (HSB), was reacted with 4,4′-bis[(4-chlorophenyl)sulfonyl]-biphenyl (CSB) in tetramethylene sulfone solvent. The highest mechanical properties and glass transition temperature was observed for polymer PBP with a reduced viscosity around 1.0 dL/g. Consequently, the current synthesis route provides polymer with higher properties than other historical preparative routes. Blends of PBP with a different poly(ether sulfone) were miscible based on the observance of a single glass transition temperature. The Tgs of the polymer blends exhibited an unusual positive deviation from the weighted linear averages of the components.  相似文献   

15.
High‐molecular‐weight poly(phthalazinone)s with very high glass‐transition temperatures (Tg's) were synthesized via a novel N–C coupling reaction. New bisphthalazinone monomers ( 7a–e ) were synthesized from 2‐(4‐chlorobenzoyl) phthalic acid in two steps. Poly(phthalazinone)s, having inherent viscosities in the range of 0.34–0.91 dL/g, were prepared by the reaction of the bis(phthalazinone) monomers with an activated aryl halide in a dipolar aprotic solvent in the presence of potassium carbonate. The poly(phthalazinone)s exhibited Tg's greater than 230 °C. polymer 8b synthesized from diphenyl biphenol and bis(4‐flurophenyl) sulfone demonstrated the highest Tg of 297 °C. Thermal stabilities of the poly(phthalazinone)s were determined by thermogravimetric analysis. All the poly(phthalazinone)s showed a similar pattern of decomposition with no weight loss below 450 °C in nitrogen. The temperatures of 5% weight loss were observed to be about 500 °C. The poly(phthalazinone)s containing 4,4′‐isopropylidenediphenol and 4,4′‐(hexafluoroisopropylidene) diphenol and diphenyl ether linkage were soluble in chlorinated solvents such as chloroform. Other poly‐(phthalazinone)s were soluble in dipolar aprotic solvents such as N,N′‐dimethylacetamide. The soluble poly(phthalazinone)s can be cast as flexible films from solution. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2481–2490, 2003  相似文献   

16.
Four new poly(arylene ether)s have been prepared by the reaction of N‐phenyl‐3,3‐bis(4‐hydroxyphenyl)phthalimidine (PA) with four different perfluoroalkylated monomers namely 1,3‐bis(4′‐fluoro‐3′‐trifluoromethyl benzyl) benzene, 4,4′‐bis(4′‐fluoro‐3′‐trifluoromethyl benzyl) biphenyl, 2,6‐bis(4′‐fluoro‐3′‐trifluoromethyl benzyl) pyridine, and 2,5‐bis(4′‐fluoro‐3′‐trifluoromethyl benzyl) thiophene. The poly(arylene ether)s were characterized by different spectroscopic, thermal, mechanical, and electrical techniques. The poly(arylene ether) containing quadriphenyl unit in the main chain showed very high glass transition temperature of 291°C and outstanding thermal stability upto 556°C for 10% weight loss under a 4:1 nitrogen:oxygen mixture. The polymers were soluble in a wide range of organic solvents. Transparent thin films of these polymers exhibited tensile strengths upto 75 MPa and elongation at break upto 32%. The films of these polymers showed low water absorption of 0.26%. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

17.
A new monomer di(4‐carboxyphenoxy) tetrakis(4‐fluorophenoxy)cyclotriphosphazene 1 was synthesized in a two‐step reaction sequence. The direct polycondensation of 1 and/or 4,4′‐dicarboxydiphenylether with aromatic ethers was carried out in P2O5/methanesulfonic acid (Eaton's reagent) at 120 °C for 3 h to give two series of aromatic poly(ether ketone)s containing cyclotriphosphazene units. The effect of the introduction of the cyclotriphosphazene group on the solubility and thermal properties of these polymers was discussed with relation to the cyclotriphosphazene contents. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 2300–2305, 2000  相似文献   

18.
Bis(4-oxybenzoic acid) tetrakis(phenoxy) cyclotriphosphazene (IUPAC name: 4-[4-(carboxyphenoxy)-2,4,6,6-tetraphenoxy-1,3,5,2λ5,4λ5,6λ5-triazatriphosphinin-2-yl]oxy-benzoic acid) was synthesized and direct polycondensed with diphenylether or 1,4-diphenoxybenzene in Eaton's reagent at the temperature range of 80–120°C for 3 hours to give aromatic poly(ether ketone)s. Polycondensations at 120°C gave polymer of high molecular weight. Incorporation of cyclotriphosphazene groups in the aromatic poly(ether ketone) backbone greatly enhanced the solubility of these polymers in common organic polar solvents. Thermal stabilities by TGA for two polymer samples of polymer series ranged from 390 to 354°C in nitrogen at 10% weight loss and glass transition temperatures (Tg) ranged from 81.4 to 89.6°C by DSC. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1227–1232, 1998  相似文献   

19.
New cyclopentylidene ring-containing diamino-diesters, 1,1-bis(3-aminobenzoyloxy phenyl) cyclopentane, was prepared through reaction of cyclopentanone with two moles of phenol to yield 1,1-bis (4-hydroxy phenyl) cyclopentane (BHPP) (I), the resulting diol (I) on reaction with 3-nitrobenzoyl chloride in N,N-dimethyl acetamide (DMAc) and triethyl amine yield 1,1-bis(3-nitrobenzoyloxy phenyl) cyclopentane (II) which on finally reduced by catalytic hydrogenation in presence of 10% Pd/C in DMAc and stirred at room temperature under a 4 kg/cm2 hydrogen pressure yields 1,1-bis(3-aminobenzoyloxy phenyl) cyclopentane (III) (m-BABPP). The structure of novel m-diester-diamine was confirmed by FT-IR, 1H-NMR and 13C-NMR. A series of new m-poly (ester-amide)s and co-poly(ester-amide)s were synthesized by using the solution polycondensation method of novel diamine (III) with IPC and TPC in various mole proportion. These novel polymers were characterized by FTIR spectroscopy, solubility, inherent viscosity and thermal analysis and XRD studies. Inherent viscosities of these polymers were in the range 0.30 to 0.46 dL/g indicating moderate molecular weight built-up. These polymers exhibited excellent solubility in various polar aprotic solvents such as NMP, Pyridine. These polymers were partially soluble in DMSO, DMAc, DMF etc.

X-Ray diffraction pattern of polymers showed that introduction of cardo moiety containing ester linkage would disturb the chain regularity and packing, leading to amorphous nature. Thermal analysis by TGA showed excellent thermal stability of polymers. The structure -property correlation among these poly(ester-amide)s were studied, in view of these polymer's potential applications as processable high temperature resistance materials.  相似文献   

20.
A series of poly(fluorenylethynylene)s containing different ratios of perylene bisimide moiety in the backbone were synthesized by Sonogashira cross‐coupling reaction. The electron‐deficient perylene bisimide moiety was introduced into the backbone to construct the donor‐acceptor architectures. The chemical structures of these copolymers were determined by 1H NMR and FTIR. The solubility, thermal, and optoelectronic properties were studied. The results of UV–vis absorption and fluorescence spectra of these copolymers showed that intramolecular energy transfer and charge separation occur between the fluorenyl alkyne segment and perylene bisimide moiety. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 1932–1938, 2008  相似文献   

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