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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.
1,3-Bis(p-phenoxybenzenesulfonyl)benzene and 4,4′-bis(p-phenoxybenzenesulfonyl)-diphenyl ether were polymerized with isophthaloyl and terephthaloyl chloride in Friedel-Crafts type polymerizations. These polymers had 5-cyanoisophthaloyl units in the backbone, obtained by using 5-cyanoisophthaloyl chloride as part of the acid chloride monomer. A number of catalysts were screened to effect the trimerization of the pendant nitrile groups in the polymer to the triazines. Model reactions were carried out for each polymer. Physical and thermal properties of the laminates obtained from these polymers are discussed.  相似文献   

3.
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   

4.
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   

5.
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   

6.
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   

7.
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   

8.
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   

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.
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   

11.
Two fluorine-containing aromatic polybenzothiazoles were synthesized by direct polycondensation of 4,4′-(hexafluoroisopropylidene)dibenzoic acid and tetrafluoroterephthalic acid with 2,5-diamino-1,4-benzenedithiol dihydrochloride using phosphorus pentoxide/methanesulfonic acid or polyphosphoric acid as both condensing agent and solvent. The effect of introduction of fluorine atom on the synthesis and properties of these polymers was discussed in detail. The perfluoroisopropylidene unit-containing polybenzothiazole was amorphous, and showed good solubility in organic solvents, excellent mechanical properties, and high thermal stability. The perfluoro-p-phenylene unit-containing polybenzothiazole was crystalline, and exhibited lyotropic behavior in concentrated sulfuric acid. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36 : 429–435, 1998  相似文献   

12.
A number of new polymeric materials have been prepared by the self-condensation of 2,5-diamino-p-benzoquinonediimide and by its condensation with 2,5-diamino-p-benzoquinone, 2,5-dihydroxy-p-benzoquinone, and 2,5-dichloro-p-benzoquinone. Ladder polymers were expected, but in every case polymers with some open rings were obtained. 2,5-Diaminohydroquinone was condensed with 2,5-diamino-p-benzoquinonediimide and with 2,5-diamino-p-benzoquinone to produce heat stable polymers but the expected ladder structures were not obtained. Thermogravimetric analyses of the polymers in nitrogen all showed a weight loss at 100–150°C of 3–14% which was presumably due to loss of either chemically combined or absorbed water on the polymer and then only a 5% weight loss up to about 600°C with a final weight loss of 19% at 900°C.  相似文献   

13.
A number of functionalized and chiral macrocyclic polyethers have been synthesized by condensation of the dithallium alcoholate of (R,R)-(+)-tartaric acid derivatives with α, ω-dihalides. In this way for instance, the tetracarboxylic [18]-O6 macrocycle 3c and its derivatives become readily available. They form complexes with various cationic substrates. NMR. and crystal-structure data provide information about the orientation of the side chains X in 3 with respect to the macrocycle. It is concluded that in the secondary amides like 3b and in their complexes the four X-groups are preferentially in an axial orientation on the average. This property is of much significance for the design of molecular receptors and catalysts based on this macrocyclic structure. The preparation of a number of other macrocycles is also described.  相似文献   

14.
A modified polysulfone containing benzylamine groups was synthesized as a reactive membrane material. Polysulfone was activated at the ortho‐sulfone site by direct lithiation with n‐butyllithium, and the resulting lithiated polysulfone was then reacted with benzonitrile; this yielded a polymer with pendant benzimine groups. The structure was confirmed by NMR and IR spectroscopy and by the transformation of imine to ketone by acid hydrolysis. The polymeric benzimine was also reduced to benzylamine with sodium cyanoborohydride in an acidic medium. The structure and degree of substitution of both benzylamine derivatives were determined by NMR and IR spectroscopy. The modified polysulfone containing benzylamine groups initiated the polymerization of N‐carboxyanhydride of γ‐benzyl‐L ‐glutamate [Glu(OBzl)–NCA]. The side‐chain oligopeptide of Glu(OBzl)–NCA attached to polysulfone was converted into molecular recognition sites. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 1316–1329, 2003  相似文献   

15.
16.
17.
Polyamides were synthesized from 2,5-dimethoxyterephthaloyl dichloride and diamines. Also, polyimines and polyaldoles were prepared from 2,5-dimethoxy-terephthaldehyde with diamines and ketones. The polymers were characterized by elemental analysis and infrared and NMR spectroscopy. Their intrinsic viscosity, glass transition temperature, and thermaldecomposition temperatures were determined.  相似文献   

18.
Degradation products of lignin, a widely available biopolymer, represent the most abundant feedstock for aromatics in nature. In this work, we focused on syringic acid, derived from lignin S-type monolignol, to synthesize different monomers for radical polymerization. The resulting polymers have molecular weight spanning over a wide range, which depends on the monomer, with up to Mn = 1,100,000 g.mol−1 and Đ = 3.0. The novel polymers exhibit a thermal stability higher than 350°C and differentiated glass transition temperatures, ranging from 105 to 120°C. One of the monomers synthesized with a free carboxyl group was able to polymerize in water—instead of organic solvent—and resulted in a water soluble polymer. Monomers from syringic acid offer a unique bio-based alternative to oil-based polystyrene in industry for a wider range of application. © 2020 Wiley Periodicals, Inc. J. Polym. Sci. 2020 , 58, 540–547  相似文献   

19.
Seven 1,3,4-thiadiazole-containing polyethers with reduced viscosities of 0.27–1.44 dL/g were synthesized by the high-temperature solution polycondensation of novel activated difluoride, 2,5-bis (4-fluorophenyl)-1,3,4-thiadiazole, with aromatic diols possessing a variety of ring structures. The expected chemical structures were confirmed by IR and 1H-NMR spectroscopy and elemental analysis. Of all the polymers, three polyethers were highly crystalline and soluble only in limited solvents such as concentrated sulfuric acid. The other polyethers were amorphous and dissolved easily in a variety of organic solvents including N-methyl-2-pyrrolidone (NMP), phenols, and chlorinated hydrocarbons. Colorless to slightly yellow-colored, transparent, and tough films could be cast from the NMP solutions of the amorphous polyethers. The mechanical properties of the films were excellent, and their tensile strength, elongation at break, and tensile moduli were in the ranges of 48–72 MPa, 5–7%, and 1.3–1.9 GPa, respectively. The amorphous polyethers had high glass transition temperatures of 204–299°C. All the polyethers were highly thermally and thermooxidatively stable and exhibited no weight loss up to 400°C, with 10% weight loss being recorded at 464–513°C in air. © 1994 John Wiley & Sons, Inc.  相似文献   

20.
Two coordination polymers, namely, two-dimensional complex 1 {[Cu(μ- L)1.5(ClO4)2(H2O)].(H2O)0.5}n (L = pyrazine-1,4-dioxide) and one-dimensional complex 2 [Co(μ-L)Br2(H2O)2]n, have been synthesized with pyrazine-1,4-dioxide as bridging ligands, and their crystal structures were determined by X-ray crystallography. Crystal data for complex 1: monoclinic system, space group C2/c, with a = 23.310(3), b = 12.2338(17), c = 10.6075(15) , β = 110.487(2)°, V = 2833.6(7) 3, Z = 8, C6H9Cl2CuN3O12.5, Mr = 457.60, Dc = 2.145 g/cm3, F(000) = 1832 and μ = 1.998 mm-1; and those for 2: monoclinic system, space group C2/c, with a = 11.012(3), b = 7.483(2), c = 11.451(3) , β = 101.654(4)°, V = 924.2(4) 3, Z = 4, C4H8Br2CoN2O4, Mr = 366.87, Dc = 2.637 g/cm3, F(000) = 700 and μ = 10.487 mm-1. 1 shows a two-dimensional sheet structure on the ac plane through the coordination of μ-L bridging ligands with Cu(II) ions, while 2 displays a zigzag one-dimensional chain along the c axis via the coordination of μ-L bridging ligand with Co(II) ions. Hydrogen bonds in 1 and 2 make the sheets (or chains) connect each other to form a three-dimensional structure.  相似文献   

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