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1.
m-Hexaphenyl ether, diphenyl ether, and 1,3-bis(p-phenoxybenzenesulfonyl)benzene were polymerized with isophthaloyl and terephthaloyl chloride in a Friedel-Crafts type polymerization. The polymers were endcapped with p-cyanobenzyl chloride or had units of 5-cyanoisophthaloyl chloride in the backbone. They were crosslinked effectively, possibly by the trimerization of the nitrile groups to triazines. Model reactions were carried out for each type of polymer.  相似文献   

2.
4,4′-Diphenoxydiphenylsulfone was polymerized with isophthaloyl chloride and terephthaloyl chloride in Friedel-Crafts polymerizations. These polymers had 5-cyanoisophthaloyl units in the backbone obtained either by using 1,3-bis(p-phenoxybenzoyl)-5-cyanobenzene or 5-cyanoisophthaloyl chloride as part of the acid chloride monomer. A terpolymer having 22 wt-% 5-cyanoisophthaloyl unit was also prepared from the Friedel-Crafts polymerization of 1,3-bis(p-phenoxybenzenesulfonyl)benzene and 5-cyanoisophthaloyl chloride. These terpolymers were crosslinked through heating to give insoluble products which proved to be thermally less stable than the uncrosslinked polymers.  相似文献   

3.
1,3-Bis(p-phenoxybenzenesulfonyl)benzene and 4,4′-diphenoxydiphenyl sulfone were polymerized with isophthaloyl and terephthaloyl chloride in Friedel-Crafts type polymerizations. These polymers had 2,4-diphenoxyacetophenone in the backbone. The acetyl group was then converted into an acetylene group. They were crosslinked effectively by cyclization of the acetylene groups with a catalyst or by cyclo-addition with bisnitrile oxides.  相似文献   

4.
Aromatic poly(keto ether sulfones) containing various amounts of pendant cyano groups were synthesized from 1,4-bis(p-phenoxybenzoyl)-2,5-dicyanobenzene, 1,3-bis(p-phenoxybenzenesulfonyl)benzene, and isophthaloyl chloride by a Friedel-Crafts type polymerization. These polymers softened at 160–190°C and had inherent viscosities of 0.44–0.61 in hexamethylphosphoric triamide. Crosslinkings were made by heating the polymers alone or in the presence of zinc chloride at 360–370°C to give black resinous materials that were insoluble in hexamethylphosphoric triamide in which the original polymers dissolved quite readily.  相似文献   

5.
Oxidation of 1,4-phenylenedimercaptan has given a cyclic trimeric disulfide. Oxidation of 1,3-phenylenedimercaptan has yielded a similar product. These monomers have been incorporated in the chains of aromatic polyether, sulfone, ketone polymers and serve as crosslinking sites on heating these polymers.  相似文献   

6.
1,3-Bis(p-phenoxybenzenesulfonyl)benzene, 4,4′-bis(p-phenoxybenzenesulfonyl)diphenyl ether, and 4,4′-diphenoxydiphenyl sulfone were polymerized with isophthaloyl or terephthaloyl chlorides in Friedel-Crafts type polymerizations. These polymers had [2,2]p-cyclophane units in the backbone, introduced by employing 3,9-bis(p-phenoxybenzoyl) [2.2]p-cyclophane as part of the polyaryl ether component. Thermolysis of the dimethylene bridge of the [2.2]p-cyclophane monomer produced diradicals which combined across polymer chains to provide crosslinks. p-Cyclophane polymers with 1,3-bis-(p-phenoxybenzenesulfonyl)benzene showed potential as high performance, thermally stable laminating resins.  相似文献   

7.
1,3-Bis(p-phenoxybenzenesulfonyl)benzene (I), 4,4′-diphenoxy-diphenyl sulfone (II), diphenyl ether, and 3,9-bis(p-phenoxybenzoyl) [2.2]-p-cyclophane were polymerized with isophthaloyl chloride in Friedel-Crafts type polymerization. The polymers obtained, containing 6–8 wt.-% of p-cyclophane units were moderately soluble in HMPA and sulfuric acid with inherent viscosities, between 0.5 and 1.0. The polymers cured at 375°C for 3 days showed little penetration up to 400°C in the Vicat softening curves. Strong molding disks and laminates on glass fiber can be made with excellent thermal stability.  相似文献   

8.
Poly(phenylene sulfides) containing various amounts of pendant cyano groups were synthesized from m-benzenedithiol and the corresponding amounts of p-dibromobenzene and 3,5-dichlorobenzonitrile. The polymers prepared by the use of 10, 15, 20, and 25% of the nitrile-containing dichloro compound were slightly off-white with melting ranges below 100°C and had inherent viscosities of about 0.15 dl/g in hexamethylphosphoric triamide at 30°C. The polymers prepared from m-benzenedithiol and the stoichiometric amounts of 2,4-dichlorobenzonitrile or 3,5-dichlorobenzonitrile looked similar to those described above, yet they possessed much higher melting ranges. The poly(phenylene sulfide) prepared by the use of 2,4-dichlorobenzonitrile had an inherent viscosity of 0.06 dl/g while the polymer prepared from the 3,5-dichloro isomer had an inherent viscosity of 0.38 dl/g. All the polymers listed above were crosslinked by heating alone or in the presence of anthracene-9,10-bisnitrile oxide to give black resinous polymers that were insoluble in hexamethylphosphoric triamide in which the original polymers dissolved quite readily.  相似文献   

9.
Polymers made from 2,2′-diiododiphenyl-4,4′-dicarbonyl dichloride, diphenyl ether, and isophthaloyl chloride have been made and converted to the 2,2′-diphenylethynyl derivatives. Introduction of units of isophthaloyl chloride reduced the melting point of these polymers to about 200°C, and they could then be cured by heating. A good glass laminate was prepared and cured from one of the polymers.  相似文献   

10.
Aromatic polyether-keto-sulfone polymers and related model compounds have been synthesized from 2,2′-diiododiphenyl-4,4′-dicarboxylic acid and a variety of intermediates. It was hoped to convert them to 2,2′-diphenylethynyl derivatives which could be cured by rearrangement to give dibenzanthracene units in the chain. Low solubilities and high melting points of the products prevented their use in the desired manner.  相似文献   

11.
4‐Fluorophenylsulfonylphenyl‐terminated polysulfone and 4‐fluorobenzoylphenyl ketone were prepared with bisphenol A and an excess of bis‐(4‐fluorophenyl)sulfone or 4,4′‐difluorobenzophenone, respectively, at 160 °C using potassium carbonate in N,N‐dimethylacetamide. The resulting polymers were reacted with 4‐hydroxystyrene to synthesize vinyl‐terminated polysulfones and ketones. The silicon‐containing polysulfones and ketones were prepared from the vinyl‐terminated polymer precursor and various H‐functional silanes or siloxanes. The synthesis of silicon‐containing polymers was achieved by hydrosilation with a rhodium catalyst. It was shown that the hydrosilation reaction proceeds with 55:45 chemoselectivity. The resulting polymers were investigated by 1H NMR spectroscopy, DSC, and thermogravimetric analysis. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 2937–2942, 2001  相似文献   

12.
Poly(phenylene sulfides) were synthesized from m-benzenedithiol and aromatic dibromides in a basic medium of potassium carbonate in dimethylformamide or dimethylacetamide. The products obtained were slightly off-white with relatively low melting ranges and had inherent viscosities in the 0.2–0.4 dl/g range in hexamethylphosphoric triamide. Similar poly(phenylene sulfides) containing pendant cyano groups along the polymer chains were obtained by the use of 5 mole-% of either 2,4-dichlorobenzonitrile or 3,5-dichlorobenzonitrile. The products were similar to the pure polyphenylene sulfides, except that they showed lower melting ranges and gave insoluble products when heated alone or in the presence of zinc chloride.  相似文献   

13.
Twelve structurally different bis- and tetramaleimides were synthesized by Friedel–Crafts reaction between 4-maleimido-benzoylchloride or 3,5-bismaleimido-benzoylchloride and various aromatic reagents. They were characterized by infrared (IR) and proton nuclear magnetic resonance (1H-NMR) spectroscopy. Crosslinked resins were obtained by curing the monomers at 250°C/6 h. Thermal characterization of monomers and cured resins was accomplished by differential thermal analysis (DTA), dynamic thermogravimetric analysis (TGA), and isothermal gravimetric analysis (IGA). Tetramaleimides were polymerized at lower temperatures than did the respective bismaleimides. The cured resins were stable up to 317–385°C in N2 atmosphere and formed an anaerobic char yield of 52–66% at 800°C.  相似文献   

14.
A polymer with high aromatic ring content in the chain backbone usually has high heat and flame resistance. Three diglycidyl ethers of epoxy resins were prepared from bisphenol A (DGEBA), phenolphthalein (DGEPP), and 9,9-bis(4-hydroxyphenyl)fluorene (DGEBF) in a study of the relation between the cured polymer structure and properties. The epoxy resin prepared from phenolphthalein was separated by liquid chromatography and three fractions were obtained. The fractions had a basic structure of 3,3-disubstituted phthalide and differed only in molecular weight. The DGEPP resin changed color from yellow to red after mixing with trimethoxyboroxine (TMB), the curing agent, and to orange after completing the curing cycle. To prepare a highly crosslinked material with good thermal stability, TMB with three active Lewis sites in a molecule was used as the curing agent. The reactivity of the three different resins toward TMB, measured by differential scanning calorimetry (DSC), was DGEBA > DGEBF > DGEPP. For the same curing conditions the order of crosslink density was DGEBA > DGEPP > DGEBF. To modify the flammability of DGEBA, the conventional epoxy resin, it was copolymerized with DGEPP and DGEBF, the higher-performance epoxy resins. The glass transition temperatures of poly(DGEBA-co-DGEPP) and poly(DGEBA-co-DGEBF) systems deviated from this relationship. The DGEBF copolymers showed an increased char residue (40 wt % at 700°C) at 20 mole % of DGEBF. This deviation may be due to the lower crosslinking density of this system.  相似文献   

15.
Various difluoro functionalized aromatic 1,3,5-triazine monomers were prepared. A series of poly-(1,3,5-triazine-ether)s was synthesized by polycondensation with 4,4′-(hexafluoroisopropylidene)diphenol. The polymers have excellent thermal stability and are amorphous with glass transition temperatures in the range of 190–250°C. In order to examine the potential to apply these polymers in organic electroluminescent devices, the redox properties were studied by cyclic voltammetry. It was found that the monomers have high electron affinity and reach LUMO values in the range of −2.7 to −3.1 eV. This opens the possibility to utilize 1,3,5-triazine containing materials as electron injecting/hole blocking layer in LEDs. First LED results are in accordance to these high electron affinities.  相似文献   

16.
17.
A comparative study was performed on strong anion exchangers to investigate the pH dependence, titration curves, efficiency, binding strength, particle size distribution, and static and dynamic capacity of the chromatographic resins. The resins tested included Q Sepharose XL, UNO Q-1, Poros 50 HQ, Toyopearl QAE 550c, Separon HemaBio 1000Q, Q-Cellthru Bigbeads Plus, Q Sepharose HP and Toyopearl SuperQ 650s. Testing was performed with five different proteins: anti-Factor VII monoclonal antibody (immunoglobulin G), aprotinin, bovine serum albumin, lipolase and myoglobin. The dependence of pH on retention varies from generally low to very high for proteins with a low isoelectric point (pl). An unexpected binding at pH 7-8 of aprotinin with pI >11 was observed on Separon HemaBio 1000Q. No link between pH dependence on retention and titration curves of the different resins was observed. Efficiency results show the expected trend of higher dependence of the plate height with increasing flow-rate of soft resins compared to resins for medium- and high-pressure operation. No or a very small difference in particle size distribution was obtained between new and used resins. Binding to anion-exchange resins as a function of ionic strength varies to some extent depending on the specific protein. Generally, binding and elution at high salt concentration may be performed with Q Sepharose XL, Toyopearl QAE 550c, Q Sepharose HP and Poros 50 HQ, while binding and elution at low salt concentration may be performed with Q-Cellthru Bigbeads Plus. A very high binding capacity was obtained with Q Sepharose XL. Comparison of static capacity and dynamic capacity at 10% breakthrough shows approx. 50-80% utilization of the total available capacity during chromatographic operation. A general good agreement was obtained between this study and data obtained by the suppliers. The results of this study may be used for selection of resins for testing in process development.  相似文献   

18.
官建国 《高分子科学》2010,28(6):961-969
<正>A high performance thermosetting epoxy resin crosslinkable at room temperature was obtained via directly moulding diglycidyl ether of bisphenol A(DGEBA) and flexibleα,ω-bisamino(n-alkylene)phenyl terminated poly(ethylene glycol).The influences of the n-alkylene inserted in aminophenyl of flexible amino-terminated polythers(ATPE) on the mechanical properties,fractographs and curing kinetics of the ATPE-DGEBA cured products were studied.The results show that the insertion of n-alkylene group into the aminophenyl group of the ATPE,on one hand,can significantly increase the strain relaxation rate and decrease glass transition temperature of the ATPE-DGEBA cured products,resulting in slight decrease of the Young's modulus and tensile strength,and significant increase of the toughness and elongation of the ATPE-DGEBA cured products.On the other hand,it can remarkably enhance the reactivity of amine with epoxy,much accelerating the curing rate of the ATPE-DGEBA systems.The activation energy of DGEBA cured by BAPTPE,BAMPTPE and BAEPTPE was 53.1,28.5 and 25.4 kJ·mol~(-1),respectively.The as-obtained ATPE-DGEBA cured products are homogeneous, transparent,and show excellent mechanical properties including tensile strength and toughness.Thus they are promising to have important applications in structure adhesives,casting bulk materials,functional coatings,cryogenic engineering, damping and sound absorbing materials.  相似文献   

19.
4,4′-Bis(N2)-{4-[4-(2,3-bicyclo-[2.2.1]hept-5-ene-dicarboximido)phenoxy]-phenyl(-aspartimido)-di-phenyl ether (2NAD/1020) and various similar polymer percursors were synthesized from bismaleimides by the Michael addition of two moles of aromatic diamine followed by end capping of the resultant amino-terminated bisaspartimide groups with nadic anhydride. These precursors were characterized by using Fourier-transform infrared (FT-IR), proton, and carbon-13 nuclear magnetic resonance spectroscopies (1H- and 13C-NMR). Thermal polymerization of 2NAD/1020 by heating it above its melting point gave a reddish brown thermoset polymer. The curing behavior and thermal stability of these nadimides were evaluated by differential scanning calorimetry and thermogravimetric analysis studies. Graphite fiber laminates were prepared from these polymer precursors and their mechanical properties evaluated. Gas Chromatography/Mass Spectra of the precursors and thermosets have given an understanding of their decomposition behavior. The structures of the thermosets were examined by FT-IR spectroscopy.  相似文献   

20.
The preparation of substituted phenols from cycloalkanones by elaboration of an aromatic ring is described.  相似文献   

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