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1.
Several new poly(metal phthalocyanine)imide copolymers have been prepared using 3,3′,4,4′-benzophenonetetracarboxylic dianhydride (BPTDA), metal(11) 4,4′,4″,4″′-phthalocyanine tetraamines (MPTA), p-phenylenediamine, 4,4′-methylenedianiline, and 9,9-bis(4-aminophenyl)-fluorene (BAF). The attractive feature of these polymers is their high thermooxidative and thermal stability. The polymer decomposition temperatures of all the imide copolymers are greater than 500°C in air and N atomspheres. Another noteworthy property is their high char yield: 60–78% at 800°C in a N2 atmosphere. Variation of the metal phthalocyanine concentration has a remarkable effect on the thermal stability and degree of polymerization. The most preferred molar proportion of the reagents MPTA, diamine, and BTDA is 1.25:7.5:10. These polymers may be useful in the preparation of heat-resistant films and fibers.  相似文献   

2.
Thermally stable poly(metal phthalocyanine)imide copolymers were prepared with metal(11) 4,4′,4″,4? -phthalocyanine tetraamines, 4,4′ -diamino diphenyl ether, and 3,3′,4,4′ -benzophenone tetracarboxylic dianhydride. Variables such as molar concentrations of the reagents, solvents, and temperature were investigated to optimize the conditions of the polymerization. Inherent viscosity, and infrared (IR) spectral and thermogravimetric analysis (TGA) studies were done to characterize the polymers. These polymers are stable and thier decomposition temperatures both in air and nitrogen are greater than 500°C. Their char yields at 800°C in nitrogen varied between 60 and 76%, depending on the type and concentrations of the metal phthalocyanine tetraamines. These polymers can be used to produce heat-stable films, fibers, varnishes, and adhesives.  相似文献   

3.
New metal phthalocyanine imide copolymers with high thermal stability, based on the reaction between metal (11) 4,4′,4″,4‴-phthalocyaninetetraamine, 4-aminophenylether, and 1,2,4,5-benzenetetracarboxylic dianhydride, were prepared. Infrared (IR) spectra, thermogravimetric analysis (TGA), and viscosity measurements were used to characterize these polymers. All polymers exhibited good thermal and thermooxidative stability at polymer decomposition temperatures (PDT) greater than 500°C in air and nitrogen atmosphere. Another attractive feature is their high char yields—60–75% at 800°C in nitrogen atmosphere. The ratio of the polymer decomposition temperatures in air and nitrogen atmospheres, (PDTair)/(PDT), varied from 0.94 to 0.98. These polymers have promising applications in heat-stable films, fibers, and coatings.  相似文献   

4.
The thermal reactions of pure metal(11) 4,4′,4″,4′″-phthalocyanine-tetracarboxylic acids of copper, cobalt, and nickel at 350–400°C in vacuum have been studied using Fourier transform infrared spectrometry, gas chromatography, and mass spectrometry. Based on these observations, novel in situ reactions for the synthesis of heat-resistant phthalocyanine “sheet” polymers are described. The poly(metal phthalocyanine) polymers of copper, cobalt, and nickel so synthesized have been characterized by elemental analysis, infrared spectroscopy, and dynamic thermogravimetric analysis. The most noteworthy property of these polymers is their extreme resistance to heat in an anaerobic atmosphere and their high char yields (89–93%) at 800°C in a nitrogen atmosphere.  相似文献   

5.
In spite of the difunctionality of the monomers, cationic polymerization of 1,3- and 1,4-diisopropenylbenzene does not lead to branched or cross-linked products. Instead, soluble polymers are obtained, containing the 1,1,3-trimethylindane system as repetitive unit along the backbone. These polymers are interesting materials because of their high glass transition temperature (200°C-250°C) and good thermal stability in air (2% weight loss at 450°C). Although the molar mass of the polyindanes seems to be limited due to a side reaction, it is possible to produce telechelic polyindanes. Substitution of an alkyl side chain onto the isopropenyl groups of 1,4-diisopropenylbenzene leads to monomers which yield substituted polyindanes with glass transition temperatures as low as 26°C. Such polymers still exhibit good thermal stability: at 340°C a weight loss of only 2% occurs. 1,4-Diisopropenylbenzene can even be anionically polymerized to linear polymers. In this case, the resulting polymer possesses isopropenyl phenyl side groups, which can be used as initiators for cationic polymerization of isobutene to obtain grafted copolymers.  相似文献   

6.
Wholly aromatic ordered copolyamides of unusually high thermal stability were prepared by the condensation of aromatic diacid chlorides with symmetrical diamines containing preformed aromatic amide units in an ordered arrangement. The preservation of order in the condensation step was assured by using interfacial or solution polymerization techniques at temperatures below 50°C. Each polymer contains units derived from aminobenzoic acids, arylene diamines, and arylene diacids. By use of para- and meta- phenylene units, eight different polymers are possible; all were prepared. Differential thermal analyses and thermogravimetric analyses showed these polymers to have melting points or decomposition temperatures in a range from 410°C. for the all-meta polymer to 555°C. for the all-para one. Substitution of the internal N-hydrogens of the diamines with methyl groups or phenyl groups leads to additional ordered copolymers. Several were prepared, but their melting points were much lower than those of the parent polymers limiting their usefulness in high temperature applications. Tough pliable films were prepared from all eight unsubstituted polymers, and crystalline fibers with tenacities of ca. 6 g./den. were prepared from three of the polymers. The properties of the fibers were retained to a high degree even when determined at temperatures up to 400°C. Fibers aged at 300°C. for extended periods of time showed remarkable retention of fiber properties.  相似文献   

7.
Poly(metal phthalocyanine)imides of copper, cobalt, nickel, and zinc were synthesized by the reaction of metal phthalocyanino tetramines with benzophenone tetracarboxylic dianhydride. These polymers were characterized by elemental analyses and IR, TGA, and inherent viscosity studies. Noteworthy features of these phthalocyanine polymers are their remarkable thermal and thermooxidative stabilities with char yields at 800°C that range from 78 to 83% in a nitrogen atmosphere. The relative thermal stabilities of these polymers have been evaluated by activation energy measurements.  相似文献   

8.
Polymerization of butadiene sulfone (BdSO2) by various catalysts was studied. Azobisisobutyronitrile (AIBN), butyllithium, tri-n-butylborn (n-Bu)3B, boron trifluoride etherate, Ziegler catalyst, and γ-radiation were used as catalysts. Butadiene sulfone did not polymerize with these catalysts at low temperatures (below 60°C.), but polymers were obtained at high temperature with AIBN or (n-Bu)3B. The polymerization of BdSO2 initiated by AIBN in benzene at 80–140°C. was studied in detail. The obtained polymers were white, rubberlike materials and insoluble in organic solvents. The polymer composition was independent of monomer and initiator concentrations and reaction time. The sulfur content in polymer decreased with increasing polymerization temperature. The polymers prepared at 80 and 140°C. have the compositions (C4H6)1.55- (SO2) and (C4H6)3.14(SO2), respectively, and have double bonds. These polymers were not alternating copolymers of butadiene with sulfur dioxide. The polymerization mechanism was discussed from polymerization rate, polymer composition, and decomposition rate of BdSO2. From these results, the polymerization was thought to be “decomposition polymerization,” i.e., butadiene and sulfur dioxide, formed by the thermal decomposition of BdSO2, copolymerized.  相似文献   

9.
The polymerization and copolymerization of 4-vinylcatechols, such as 2-(0-methyl)-4-vinylcatechol (I), 3,4-dimethoxystyrene (II), and 3,4-methylenedioxystyrene (III), were investigated in cyclohexanone at 30°C, using tri-n-butylborane as an initiator. The reactions yielded vinyl polymers and copolymers. The copolymerization parameters of I–III were determined; their Q and e values were found to be similar to those of styrene and vinylhydroquinone. The copolymerization of I–III gave copolymers of a highly alternating character. The thermal stability of the polymers and copolymers so obtained was also studied. The redox potentials of hydroloyzed poly(I) were examined; the reverse “polymer effect” was observed.  相似文献   

10.
Aromatic polyamides were prepared by an AlCl3 or HCl-catalyzed polymerization of toluene diisocyanate or methylenebis(phenyl isocyanate) with adipic acid at low temperatures (≤100°C) in a short reaction time (3–4 h). The intrinsic viscosity of the polymers was approximately 1.1 dL/g as determined at 25°C with m-cresol as solvent, indicating that the polyamides obtained by this method have relatively high molecular weights. The polymers exhibit high glass transition temperatures and good thermal stability.  相似文献   

11.
A novel class of semifluorinated perfluorocyclohexenyl (PFCH) aryl ether homo/copolymers was successfully synthesized with high yield through the step‐growth polymerization of commercially available bisphenols and decafluorocyclohexene in the presence of a triethylamine base. The synthesized polymers exhibit variable thermal properties depending on the functional spacer group (R). PFCH aryl ether copolymers with random and alternating architectures were also prepared from versatile bis‐perfluorocyclohexenyl aryl ether monomers. The PFCH polymers show high thermal stabilities with a 5% decomposition temperature ranging from 359 to 444 °C in air and nitrogen atmosphere. These semifluorinated PFCH aromatic ether polymers contain intact enchained PFCH olefin moieties, making further reactions such as crosslinking and application specific functionalization possible. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 232–238  相似文献   

12.
The article deals with synthesis, characterization, and polymerization of 5-norbornene-2,3-dicarboximide end-capped resins (bisnadimides) based on 4,4′-diaminodiphenylether, 1,4/1,3-bis(4′-aminophenoxy) benzene, 2,2′-bis[4-(4′-aminophenoxy)phenyl]propane, and bis[4-(4′-aminophenoxy)phenyl]sulphone. Both exo and endo bisnadimides were prepared by reacting the aromatic diamines with exo or endo nadic anhydride in glacial acetic acid at 120°C. The exo or endo bisnadimides could be distinguished on the basis of differences observed in IR or 1H-NMR spectra. Both thermal (in solid state) and metathetical polymerization (using WCl6/tetramethyltin catalyst and chlorobenzene solvent) of bisnadimides was carried out. Only exo bisnadimides could be polymerized using metathesis reaction whereas thermal polymerization of both endo and exo bisnadimide could be successfully carried out at 300°C in static air atmosphere. The polymers were highly crosslinked and insoluble in common organic solvents. The polymers obtained by metathesis polymerization were light brown in color whereas those obtained by thermal polymerization were dark brown in color. Thermal stability of the thermally polymerized exo or endo bisnadimides was comparable. These polymers were stable up to 400°C and decomposed in a single step above this temperature. The char yield at 800°C depended on the structure of the polymer and was in the 39–56% range. The polymers formed by metathesis polymerization showed a 1–3% weight loss in the temperature range 226–371°C and decomposed in a single step above 440°C. The char yields were higher in these polymers (53–71%) compared to those obtained by thermal polymerization. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35 : 2323–2331, 1997  相似文献   

13.
This work studies the synthesis of copolymers (MACO‐St) of castor oil maleate (MACO) and styrene (St) initiated using benzoyl peroxide (BPO) as free radical initiator through suspension polymerization. The study investigates the effects of temperature (100–140 °C), the molar ratio between styrene and MACO (2:1–4:1), BPO concentration (0.10–0.20 wt%), and water concentration (50–100 wt%) on the molecular weight distribution, thermal stability, viscosity, and biodegradability of the copolymers. Suspension polymerization allows the production of a broad range of number average molecular weight (3465–18 995 g mol?1) and molecular weight distributions with dispersions (?) ranging from 1.8 to 4.4. The reaction presents high yields of castor oil into copolymers (>90%), which displays thermal stability up to 200 °C and are highly biodegradable according to the International Organization of Standardization reference.  相似文献   

14.
Novel fire- and heat-resistant polymers was obtained by the thermal polymerization of various maleimidophenoxy-triphenoxycyclotriphosphazenes. These polymers, in which the cyclic triphosphazene structure is preserved, have thermal stability to 350°C and char yields of 82–78% at 800°C in nitrogen and 78–71% at 700°C in air. Two groups of monomers were synthesized by reacting tris(4-aminophenoxy)-tris(phenoxy)cyclotriphosphazene with maleic anhydride alone or in combination with benzophenonetetracarboxylic or pyromellitic dianhydride. The structures of cyclic phosphazene-trimeric precursors and the polymers were characterized by Fourier-transform infrared, proton nuclear magnetic resonance, and elemental analysis. The thermal stabilities of the polymers were evaluated by thermogravimetric analysis.  相似文献   

15.
The mechanical properties and thermal stability of polymers can be enhanced through the formation of nanocomposites. Nanocomposites consisting of hybrid copolymers of methacrylcyclohexyl polyhedral oligomeric silsesquioxane (POSS‐1) and methyl methacrylate (MMA) with up to 92 wt % (51 mol %) POSS‐1 and with superior thermal properties were synthesized using solution polymerization. The POSS‐1 contents of the copolymers were similar to or slightly higher than those in the feeds, the polydispersity indices were relatively low, and the degree of polymerization decreased with increasing POSS‐1 content. POSS‐1 enhanced the thermal stability, increasing the degradation temperature, reducing the mass loss, and preventing PMMA‐like degradation from propagating along the chain. The mass loss was reduced in a high POSS‐1 content copolymer since the polymerization of POSS‐1 with itself reduced sublimation. Exposure to 450 °C produced cyclohexyl‐POSS‐like remnants in the POSS‐1 monomer and in all the copolymers. The degradation of these remnants, for the copolymers and for the POSS‐1 monomer, yielded 75% SiO2 and an oxidized carbonaceous residue. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4264–4275, 2007  相似文献   

16.
The study described here deals with the methods of synthesis of two new bisphthalonitrile derivatives with ester—imide linkages and their polymerization. Optimum conditions for the synthesis and characterization of the bisphthalic anhydrides, bisphthalonitriles, and polymers are developed using IR spectral, differential scanning calorimetric, dynamic thermogravimetric analytical, and mass spectral studies. These new polymers showed good thermal stability and chemical inertness. The polymers showed char yield of 50% at 800°C in nitrogen atmosphere. These thermosetting phthalocyanine polymers are expected to be useful in various applications such as the production of moulded articles and laminates.  相似文献   

17.
张林常冠军   《中国化学》2009,27(2):428-432
以不同的二碘化合物和芳香二胺为单体,通过两种不同的方法经缩聚反应得到了系列高分子量、低分布的聚芳亚胺。其结构由FT-IR, 1H NMR1和元素分析表征。由DSC和TG测定结果可知,该系聚合物具有较高的玻璃化转变温度(Tg>150℃)和良好的热稳定性(TD>400℃)。另外,该系聚合物还表现出良好的溶解性能。  相似文献   

18.
Fluorescent hyperbranched copolymers (HB‐x, x = 1–4) with inherent tetraphenylthiophene, triphenylamine (TPA) and quinoline (Qu) moieties were prepared to study the influence of the TPA branching point on the thermal and the spectral stability. All the HB‐x copolymers exhibited high glass transition temperatures (Tgs = 245–315 °C) with the detected values increasing with the increasing branching TPA content in the HB‐x. The solid HB‐x films possess high emission efficiency with the resulting quantum yields (?Fs) in the ranges of 0.72–0.74. More importantly, the HB‐x copolymers and the derived light‐emitting devices exhibit high photoluminescence (PL) and electroluminescence (EL) stability towards thermal annealing at temperatures higher than 200 °C. After annealing at 200 °C (or 300 °C), no change was observed in the respective PL and EL spectra of HB‐1 (or HB‐4) copolymers. The spectral stability was found to correlate with Tg and with the highest branching density, HB‐4 copolymer possesses the highest thermal stability among all HB‐xs and show no EL spectral change after annealing at 300 °C for 4 h. The results indicate that all the branched HB‐x copolymers are promising candidates for the polymer light‐emitting diodes due to their high quantum yield and spectral stability. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012  相似文献   

19.
A diverse pool of aryl bistrifluorovinyl ether (BTFVE) compounds with reactive pendant groups were prepared in a facile, high yielding three step “one‐pot” synthesis from commercial 4‐bromo(trifluorovinyloxy)benzene. Monomers were confirmed from ATR–FTIR, 1H, 13C, and 19F NMR, and HRMS analysis. Aryl BTFVE compounds were thermally polymerized to afford perfluorocyclobutyl (PFCB) aryl ether polymers with high number–average molecular weight (Mn) for homopolymers (17,050–27,090) and copolymers with 4,4′‐bis(trifluorovinyloxy)biphenyl monomers (27,860–56,500). The PFCB aryl ether homo‐ and copolymers collectively possess high thermal stability (>299 °C in N2) and are readily solution processable producing optically transparent films. The thermal polymerization was achieved and reactive moieties remained intact, aside from those functionalized with acrylates. In the case with acrylate functionalized polymers, orthogonal polymerization was achieved by first photopolymerizing the acrylates followed by thermal curing of the aryl trifluorovinyl ether endgroups. Preliminary results in this study produced the successful preparation of photodefinable PFCB aryl ether material. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1887–1893, 2010  相似文献   

20.
The anionic polymerization of a bridged bicyclic lactam, 2-azabicyclo[2,2,1]heptan-3-one (ABHO), was carried out in bulk and in solution under various reaction conditions. In general bulk polymerization of ABHO was superior to solution polymerization in conversion and degree of polymerization. The resulting polymer exhibited good thermal stability at temperatures up to 300°C. The melting point and decomposition temperature of this polyamide, poly(cyclopentane-1,3-diyliminocarbonyl), were about 307 and 335°C, respectively. Copolymerization of ABHO with 2-pyrrolidone was also made at 30°C and a varying weight percentage of ABHO with potassium pyrrolidonate as catalyst and CS2 as activator. Copolyamides that contained 15 w % of ABHO decomposed at a temperature higher than the melting point by almost 30°C. Thus the thermal stability of copolymers compared with that of nylon-4, was greatly improved. Moisture sorptions of homopolymers and copolymers were always larger than those of other polyamides (nylon 4 and 6) at any relative humidity. Tenacity and elongation at the break of melt-spun fibers obtained from copolyamides that contained 15 w % of ABHO without the drawing and annealing process were 1.25 g/den and 13.1%, respectively.  相似文献   

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