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1.
A series of new polyamides containing tetraphenyl thiophene having pendant phenyl moiety with heterocyclic quinoxaline unit were synthesized by using the solution polycondensation method of novel diamine monomer V with isopthaloyl chloride (IPC) and terpthaloyl chloride (TPC) in various mole proportions. These novel polymers were characterized by FT-IR, solubility, inherent viscosity, thermal analysis and X-ray diffraction studies. Inherent viscosities of these polymers were in the range 0.66 to 1.44 dL/g indicating moderate to high molecular weight built-up. These polymers exhibited solubility in various solvents such as DMAc, NMP, pyridine, m-cresol etc. X-ray diffraction pattern of polymers showed that introduction of pendant phenyl moiety would disturb the chain regularity and packing, leading to amorphous nature. Thermal analysis by TGA and DSC showed excellent thermal stability of polymers. The structure -property correlation among these polyamides were studied, in view of these polymer's potential applications as processable high temperature resistance materials.  相似文献   

2.
A new category of poly(ester-amide)s based on diarylidenecyclohexanone in the main chain were synthesized via interfacial polycondensation of two monomers namely: 2,6-bis(4-hydroxybenzylidene) cyclohexanone I and 2,6-bis(4-hydroxy-3-methoxybenzylidene) cyclohexanone II with diacid chlorides IIIa–c. The model compounds were synthesized by reacting one mole of compounds IVa–c with two monomers I and II. The structure of the model compounds was confirmed by correct elemental and spectral analyses. The various characteristics of the resulting polymers including: solubility, viscosity, thermal analysis, and X-ray diffraction analysis were determined and discussed. The majority of the polymers were insoluble in most common organic solvents. The viscosity measurements in dimethylsulfoxide showed the values 0.58–0.79 dl/g. Thermal analysis showed that they were thermally stable up to 500 °C. X-ray analysis showed that the polymers had some degree of crystallinity in the region 2θ = 5–50°.  相似文献   

3.
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   

4.
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   

5.
梁璐  刘白玲  陈华林  徐前 《合成化学》2005,13(5):483-485
以顺丁烯二酸酐、二乙醇胺、邻苯二甲酸酐等为原料,利用官能团活性的差异,通过逐步展开的方法合成了含有双键和端羟基的聚(酯-酰胺)型分子结构的超支化大单体(3)。IR分析表明:3的分子末端为大量伯羟基,具有较高的反应活性;3含有可供聚合的乙烯基,将3与其它乙烯基单体共聚可以获得含超支化结构的共合物。  相似文献   

6.
N-(4-chloro-3-aminobenzal)N′(4-aminophenyl)thiourea having phenylthiourea and azomethine groups was synthesized and exploited as starting material for the fabrication of new polymers. Novel diamine was condensed with pyromellitic dianhydride, 3,3′,4,4′-benzophenone-tetrcarboxylic dianhydride and 4,4′-(hexafluoroisopropylidene) diphthalic dianhydride to obtain poly(phenylthiourea azomethine imide)s. The structural explication of monomers and poly(phenylthiourea azomethine imide)s were carried out by FTIR, 1H and 13C NMR techniques along with crystallinity, organosolubility, inherent viscosity and molecular weight measurements. Accordingly, polymers bearing CS and -CN- moieties in the backbone demonstrated an amorphous nature and were readily soluble in amide solvents such as DMAc, DMF, and DMSO. Poly(phenylthiourea azomethine imide)s encompassed ηinh of 1.40-1.55 dL/g and were obtained in quantitative yields. In addition, GPC measurements of polymers revealed Mw around 60,291-67,665. Thermal stability of these polymers was ascertained via 10% weight loss temperatures around 514-533 °C in an inert atmosphere. Besides, glass transition temperatures of polyimides were found to be 272-276 °C.  相似文献   

7.
Several new co‐poly(arylene ether sulfone)s have been prepared by the reaction of 4,4′‐fluorodiphenyl sulfone (FDS) with different bisphenols namely 4,4′‐isopropylidenediphenol (BPA), 4,4′‐hexafluoroisopropylidenediphenol (6F‐BPA), and N‐phenyl‐3,3‐bis(4‐hydroxyphenyl)phthalimidine(PA). The homo‐poly(arylene ether sulfone)s are named as 1a, 2a, and 3a. The copolymers namely 2b, 2c, 2d and 3b, 3c, 3d have been prepared, respectively, on reaction of FDS with BPA or 6F‐BPA using different molar ratios of PA such as 25, 50, and 75. The poly(aryl ether sulfone)s 1a containing PA unit in the main chain showed a very high glass transition temperature of 280°C and an outstanding thermal stability up to 510°C for 5% weight loss under synthetic air. Depending on the mole% of PA, the glass transition temperatures of the copolymers can be varied. The polymers were soluble in a wide range of organic solvents. Transparent thin films of these polymers exhibited tensile strengths upto 84 MPa and Young's modulus up to 3.16 GPa. The films of these polymers showed low water absorption of 0.24%. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

8.
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   

9.
Polylactide (PLA), made from agriculture products, was one of biodegradable polymers1,2. Owing to its characters, PLA and its copolymers have received great interest in industrial and medical applications3-6, such as drug delivery systems, sutures, artifi…  相似文献   

10.
Unsaturated bisamic acids were prepared by reaction between maleic anhydride and different aromatic diamines. Unsaturated poly(ester-amide) resin (UPEAs) was prepared by reaction of diglycidylether of bisphenol-A (DGEBA) with unsaturated bisamic acids. Acrylation of Unsaturated poly(ester-amide)s (UPEAs) was carried out to afford acrylated UPEAs resin (i.e., AUPEAs). Interacting blends of Acrylated unsaturated poly(ester-amide)s (AUPEAs) with vinyl ester epoxy (VE) resin were prepared. APEAs and AUPEAs were characterized by elemental analysis, molecular weight determined by vapor pressure osmometer and by IR spectral study and by thermogravimetry. The curing of interacting blends was monitored on differential scanning calorimeter (DSC). Based on DSC data in situ glass reinforced composites of the resultant blends have been prepared and characterized for mechanical, electrical and chemical properties. Unreinforced blends were characterized thermo-gravimetrically (TGA).  相似文献   

11.
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   

12.
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   

13.
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   

14.
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   

15.
Random copoly(p-phenylene sulfide sulfone/ketone)s (PPSS/K) are prepared in high yield by the polycondensation of sodium hydrosulfide (NaSH) with bis(4-chlorophenyl) sulfone (BCPS) and 4,4′-dichlorobenzophenone (DCBP). The polymerization is conducted between 200–220°C, depending on the composition of the copolymer, and in the presence of water without any detrimental effects to the molecular weight. The copolymers with sulfone/ketone mole ratios (S : K) > 25 : 75 are amorphous, while the copolymers with S : K ratios ≤ 25 : 75 are crystalline. These materials form tough, creaseable films and exhibit a linear increase in the glass transition temperature with increasing sulfone content. Sulfuric acid solutions of the copolymers are dark orange to red and display an increasing λmax in the uv-visible spectra as the S:K ratio of the copolymers decreases. © 1994 John Wiley & Sons, Inc.  相似文献   

16.
以季戊四醇为"核分子"超支化聚酯-酰胺的合成及表征   总被引:4,自引:0,他引:4  
以二异丙醇胺(DIPA)与六氢苯酐(HHPA)为原料合成了一种端基带有一个羧基、两个羟基的AB2型单体。用季戊四醇(PETL)作为“核分子”,按一定的摩尔配比与AB2型单体反应,分别得到两种不同的超支化聚酯-酰胺(1GHP、2G—HP)。并采用红外光谱(IR)、凝胶渗透色谱法(GPC)、粘度法等方法对其结构进行了表征。结果表明:1GHP、2G—HP的多分散性指数分别为1.47和2.17,呈现很窄的分子量分布。两种分子的粘度与浓度的关系服从Einstein粘度方程,具有紧凑的球形分子结构。  相似文献   

17.
Copolymerizations of p-dichlorobenzene (DCB)/4-bromophenyl ether (BPE), DCB/4,4′-dibromobiphenyl (DBB), and DBB/BPE pairs with sodium sulfide under high temperature (270–290°C) utilizing N-methyl-2-pyrrolidinone (NMP) as solvent were carried out to give C(DCB/BPE), C(DCB/DBB), and C(DBB/BPE) copolymers, respectively. The reactivity of dihaloaromatic monomers toward thiolate anion in the polycondensation reaction followed the order DBB > DCB > BPE. The reactivity gap between DBB and DCB toward thiolate anion seemed to be smaller than that between BPE and DCB, resulting in both high yield and high molecular weight in the C(DCB/DBB) copolymers compared to C(DCB/BPE) copolymers. The copolymerization of DBB/BPE pair with sodium sulfide, which has larger reactivity gap than the DCB/DBB or DCB/BPE pair, gave mixtures of PBS and PPSE homopolymers especially in the range of 50–80 mol % BPE in the feed. The C(DCB/DBB) and C(DCB/BPE) copolymers, however, exhibited random copolymer character in all comonomer ratios in the feed as evidenced by copolymer composition and DSC data. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 2311–2317, 1999  相似文献   

18.
A new aromatic diamine, 2,8-di(4-aminophenyl)dibenzofuran, was synthesized through the Suzuki C-C coupling reaction. This compound and an analoge diamine also based on a dibenzofuran moiety reacted with silylated-dianhydrides to yield three aromatic oligomeric poly(ether-imide)s (PEIs). The new diamine and the oligomers were characterized by elemental analysis, FT-IR, and NMR. Additionally, for the samples, solubility in an organic polar solvent was stablished and inherent viscosity values as an indirect measure of the molecular size were recovered. Some properties of PEIs were established and related to the specific structure of the repeating unit. In this sense, the rigidity/flexibility of the main chain fragments and the volume of groups bonded to silicon atom were responsible for the final properties of the polymers. All PEIs were obtained in high yield, but the inherent viscosities values of the soluble samples were low, indicating probably, low to moderated molecular sizes. The thermal decomposition temperatures measured by TGA varied from 490 to 562°C, and the Tg values ranged between 205 and 218°C. The solubility of all samples was tested in a series of common organic solvents at room temperature and at 40°C. The optical transparency in solution for the soluble samples was also determined.  相似文献   

19.
A series of new poly(amide imide)s was prepared from new diacid containing sulfone, ether, amide and imide groups with various aromatic diamines. The diacid was synthesized via four steps, starting from reaction of 4-aminophenol with 4-nitrobenzoyl chloride in the presence of propylene oxide afforded N-(4-hydroxy phenyl)-4-nitrobenzamide. In the second step, reduction of nitro group resulted in preparation of 4-amino-N-(4-hydroxy phenyl) benzamide. In the next step for the preparation of diamine, the reaction of 4-amino-N-(4-hydroxy phenyl) benzamide with bis-(4-chlorophenyl) sulfone in the presence of K2CO3 was achieved. The prepared sulfone ether amide diamine was reacted with two moles of trimellitic anhydride to synthesize related sulfone ether amide imide diacid. The precursors and final monomer were characterized by FT-IR, H-NMR and elemental analysis. Direct polycondensation reaction of the sulfone ether amide imide diacid with different diamines in the presence of triphenyl phosphite afforded five different poly (sulfone ether amide imide amide)s. The obtained polymers were fully characterized and their physical properties including thermal behavior, thermal stability, solubility, and inherent viscosity were studied.  相似文献   

20.
A series of novel poly(aryl ether nitrile)s containing phthalazinone moiety were synthesized by the nucleophilic displacement reaction of bisphenol-like monomers (I) with 2,6-difluorobenzonitrile. The inherent viscosities ranged from 0.46 to 1.07 dL g^-1. The glass transition temperatures were in the range of 277-295℃, and the temperatures for 10% weight loss in nitrogen atmosphere were found between 495 and 527 ℃. The structures of these resultant polymers were confirmed by FT-IR and 1^H NMR. Moreover, the properties of poly(aryl ether nitrile)s including solubility and crystallinity were also studied.  相似文献   

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