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1.
A new diamine 5,5′‐bis[4‐(4‐aminophenoxy)phenyl]‐hexahydro‐4,7‐methanoindan ( 3 ) was prepared through the nucleophilic displacement of 5,5′‐bis(4‐hydroxylphenyl)‐hexahydro‐4,7‐methanoindan ( 1 ) with p‐halonitrobenzene in the presence of K2CO3 in N,N‐dimethylformamide (DMF), followed by catalytic reduction with hydrazine and Pd/C in ethanol. A series of new polyamides were synthesized by the direct polycondensation of diamine 3 with various aromatic dicarboxylic acids. The polymers were obtained in quantitative yields with inherent viscosities of 0.76–1.02 dl g−1. All the polymers were soluble in aprotic dipolar solvents such as N,N‐dimethylacetamide (DMAc) and N‐methyl‐2‐pyrrolidone (NMP), and could be solution cast into transparent, flexible and tough films. The glass transition temperatures of the polyamides were in the range 245–282 °C; their 10% weight loss temperatures were above 468 °C in nitrogen and above 465 °C in air. © 2000 Society of Chemical Industry  相似文献   

2.
A new kind of pyridine‐containing aromatic diamine monomer, 4‐phenyl‐2,6‐bis[4‐(4‐aminophenoxy)phenyl]‐pyridine (PAPP), was successfully synthesized by a modified chichibabin reaction of benzaldehyde and a substituted acetophenone, 4‐(4‐nitrophenoxy)‐acetophenone (NPAP), followed by a reduction of the resulting dinitro compound 4‐phenyl‐2,6‐bis[4‐(4‐nitrophenoxy)phenyl]‐pyridine (PNPP) with Pd/C and hydrazine monohydrate. The aromatic diamine was employed to synthesize a series of new pyridine‐containing polyimides by polycondensation with various aromatic dianhydrides in N‐methy‐2‐pyrrolidone (NMP) via the conventional two‐step method, i.e., ring‐opening polycondensation forming the poly (amic acid)s and further thermal or chemical imidization forming polyimides. The inherent viscosities of the resulting polyimides were in the range of 0.79–1.13 dL/g, and most of them were soluble in common organic solvents such as N,N‐dimethylacetamide (DMAc), NMP, and tetrahydrofuran (THF), etc. Meanwhile, strong and flexible polyimide films were obtained, which had good thermal stability, with the glass transition temperatures (Tg) of 268–338°C and the temperature at 5% weight loss of 521–548°C in air atmosphere, as well as outstanding mechanical properties with tensile strengths of 89.2–112.1 MPa and elongations at break of 9.5–15.4%. The polyimides also were found to possess low dielectric constants ranging from 2.53 to 3.11. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 212–219, 2007  相似文献   

3.
A novel fluorinated diamine monomer, 2,2‐bis[4‐(4‐amino‐2‐trifluoromethylphenoxy)phenyl]propane (2), was prepared through the nucleophilic substitution reaction of 2‐chloro‐5‐nitrobenzotrifluoride with 2,2‐bis(4‐hydroxyphenyl)propane in the presence of potassium carbonate, followed by catalytic reduction with hydrazine and Pd/C. Polyimides were synthesized from diamine 2 and various aromatic dianhydrides 3a–f via thermal imidization. These polymers had inherent viscosities ranging from 0.73 to 1.29 dL/g. Polyimides 5a–f were soluble in amide polar solvents and even in less polar solvents. These films had tensile strengths of 87–100 MPa, elongations to break of 8–29%, and initial moduli of 1.7–2.2 GPa. The glass transition temperatures (Tg) of 5a–f were in the range of 222–271°C, and the 10% weight loss temperatures (T10) of them were all above 493°C. Compared with polyimides 6 series based on 2,2‐bis[4‐(4‐aminophenoxy)phenyl]propane (BAPP) and polyimides 7 based on 2,2‐Bis[4‐(4‐aminophenoxy)phenyl]hexafluoropropane (6FBAPP), the 5 series showed better solubility and lower color intensity, dielectric constant, and lower moisture absorption. Their films had cutoff wavelengths between 363 and 404 nm, b* values ranging from 8 to 62, dielectric constants of 2.68–3.16 (1 MHz), and moisture absorptions in the range of 0.04–0.35 wt %. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 95: 922–935, 2005  相似文献   

4.
To investigate the CF3 group affecting the coloration and solubility of polyimides (PI), a novel fluorinated diamine 1,1‐bis[4‐(4‐amino‐2‐ trifluoromethylphenoxy)phenyl]‐1‐phenylethane (2) was prepared from 1,1‐ bis(4‐hydrophenyl)‐1‐phenylethan and 2‐chloro‐5‐nitrobenzotrifluoride. A series of light‐colored and soluble PI 5 were synthesized from 2 and various aromatic dianhydrides 3a–f using a standard two‐stage process with thermal 5a– f(H) and chemical 5a–f(C) imidization of poly(amic acid). The 5 series had inherent viscosities ranging from 0.55 to 0.98 dL/g. Most of 5a–f(H) were soluble in amide‐type solvents, such as N‐methyl‐2‐pyrrolidone (NMP), N,N‐ dimethylacetamide (DMAc), and N,N‐dimethylformamide (DMF), and even soluble in less polar solvents, such as m‐Cresol, Py, Dioxane, THF, and CH2Cl2, and the 5(C) series was soluble in all solvents. The GPC data of the 5a–f(C) indicated that the Mn and Mw values were in the range of 5.5–8.7 × 104 and 8.5–10.6 × 104, respectively, and the polydispersity index (PDI) Mw /Mn values were 1.2–1.5. The PI 5 series had excellent mechanical properties. The glass transition temperatures of the 5 series were in the range of 232–276°C, and the 10% weight loss temperatures were at 505–548 °C in nitrogen and 508–532 °C in air, respectively. They left more than 56% char yield at 800°C in nitrogen. These films had cutoff wavelengths between 356.5–411.5 nm, the b* values ranged from 5.0–71.1, the dielectric constants, were 3.11–3.43 (1MHz) and the moisture absorptions were in the range of 011–0.40%. Comparing 5 containing the analogous PI 6 series based on 1,1‐bis[4‐(4‐aminophenoxy)phenyl]‐1‐ phenylethane (BAPPE), the 5 series with the CF3 group showed lower color intensity, dielectric constants, and better solubility. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 2399–2412, 2005  相似文献   

5.
A new aromatic diamine, 2,3‐bis(4‐(4‐amino‐2‐(trifluoromethyl) phenoxy)phenyl)naphtho[2,3‐f]quinoxaline‐7,12‐dione, was synthesized and fully characterized by using FTIR, 1H and 13C NMR, DEPT technique, and elemental analysis. A series of novel fluorescent anthraquinone‐quinoxaline containing polyamides (PAs) with inherent viscosities of 0.39–0.62 dL/g was prepared by direct polycondensation of the diamine with various dicarboxylic acids. These PAs were readily soluble in many polar aprotic organic solvents and could be solution‐cast into tough and flexible films. The PAs exhibited glass transition temperatures (Tg)s between 230 and 323°C, and 10% weight loss temperatures in the range of 362–433°C in N2. All of the PAs have fluorescence emission in solution and in solid state with maxima around 452–510 nm and with the quantum yields in the range of 6–17%. Also, cyclic voltammetry (CV) method was used to study the electrochemical oxidation behavior of these polymers at the surface of a modified multiwalled carbon nanotube (MWCNT)s glassy electrode. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

6.
The quantitative syntheses of α‐bis and α,ω‐tetrakis tertiary diamine functionalized polymers by atom transfer radical polymerization (ATRP) methods are described. A tertiary diamine functionalized 1,1‐diphenylethylene derivative, 1,1‐bis[(4‐dimethylamino)phenyl]ethylene (1), was evaluated as a unimolecular tertiary diamine functionalized initiator precursor as well as a functionalizing agent in ATRP reactions. The ATRP of styrene, initiated by a new tertiary diamine functionalized initiator adduct (2), affords the corresponding α‐bis(4‐dimethylaminophenyl) functionalized polystyrene (3). The tertiary diamine functionalized initiator adduct (2) was prepared in situ by the reaction of (1‐bromoethyl)benzene with 1,1‐bis[(4‐dimethylamino)phenyl]ethylene (1) in the presence of a copper (I) bromide/2,2′‐bipyridyl catalyst system. The ATRP of styrene proceeded via a controlled free radical polymerization process to afford quantitative yields of the corresponding α‐bis(4‐dimethylaminophenyl) functionalized polystyrene derivative (3) with predictable number‐average molecular weight (Mn) and narrow molecular weight distribution (Mw/Mn) in a high initiator efficiency reaction. The polymerization process was monitored by gas chromatography analysis. Quantitative yields of α,ω‐tetrakis(4‐dimethylaminophenyl) functionalized polystyrene (4) were obtained by a new post ATRP chain end modification reaction of α‐bis(4‐dimethylaminophenyl) functionalized polystyrene (3) with excess 1,1‐bis[(4‐dimethylamino)phenyl]ethylene (1). The tertiary diamine functionalized initiator precursor 1,1‐bis[(4‐dimethylamino)phenyl]ethylene (1) and the different tertiary amine functionalized polymers were characterized by chromatography, spectroscopy and non‐aqueous titration measurements. Copyright © 2012 Society of Chemical Industry  相似文献   

7.
Two oxetane‐derived monomers 3‐(2‐cyanoethoxy)methyl‐ and 3‐(methoxy(triethylenoxy)) methyl‐3′‐methyloxetane were prepared from the reaction of 3‐methyl‐3′‐hydroxymethyloxetane with acrylonitrile and triethylene glycol monomethyl ether, respectively. Their homo‐ and copolyethers were synthesized with BF3· Et2O/1,4‐butanediol and trifluoromethane sulfonic acid as initiator through cationic ring‐opening polymerization. The structure of the polymers was characterized by FTIR and1H NMR. The ratio of two repeating units incorporated into the copolymers is well consistent with the feed ratio. Regarding glass transition temperature (Tg), the DSC data imply that the resulting copolymers have a lower Tg than pure poly(ethylene oxide). Moreover, the TGA measurements reveal that they possess in general a high heat decomposition temperature. The ion conductivity of a sample (P‐AN 20) is 1.07 × 10?5 S cm?1 at room temperature and 2.79 × 10?4 S cm?1 at 80 °C, thus presenting the potential to meet the practical requirement of lithium ion batteries for polymer electrolytes. Copyright © 2005 Society of Chemical Industry  相似文献   

8.
A series of polyimide (PI) thin films were synthesized based on bis[3,5‐dimethyl‐4‐(4‐aminophenoxy)phenyl]methane and conventional aromatic dianhydrides. The structures and properties of the thin films were measured with Fourier transform infrared, NMR, thermogravimetric analysis, dynamic mechanical analysis, and impedance analysis. The PI films exhibited glass‐transition temperatures in the range of 211–300°C and possessed initial thermal decomposition temperature reaching up to 457–482°C in air and 461–473°C in nitrogen. Some PI films had high solubility in organic solvents such as 1‐methyl‐2‐pyrrolidinone, N,N‐dimethylformamide, N,N‐dimethylacetamide, dimethyl sulfoxide, m‐cresol, tetrahydrofuran, and CHCl3. The mechanical properties of these films were also examined. The dielectric constants of the films were in the range of 2.8–3.3 at 25°C. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1265–1270, 2007  相似文献   

9.
A series of poly(urethane)s (PUs) based on diphenyl‐silane or ‐germane and oxyphenyl units were synthesized by polycondesation of 4‐[4‐[9‐[4‐(4‐aminophenoxy)‐3‐methyl‐phenyl]fluoren‐9‐yl]‐2‐methyl‐phenoxy]aniline (3) and four bis(chloroformate)s ( I–IV ). These monomers were prepared and characterized in previous works. The best conditions for the polymerization reactions were investigated by a kinetic study. Also, a selection of the best solvent for the reaction was developed. Polymers were characterized by IR and 1H, 13C, and 29Si‐NMR spectroscopy and the results were in agreement with the proposed structures. Poly(urethane)s showed inherent viscosity values between 0.12 and 0.31 dL/g, indicative of low molecular weight species, probably of oligomeric nature. The glass transition temperature (Tg) values were observed in the 127–168°C range by DSC analysis. Thermal decomposition temperature (TDT10%) values were above 300°C. All PUs showed good transparency in the visible region (>80% at 350 nm) due to the incorporation of the bulky monomer (fluorene) and oxyether linkages. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

10.
A new para-linked diether-diamine, 9,9-bis{4-[2-(4,5-diphenylimidazol-2-yl)-4-aminophenoxy] phenyl}fluorene (III), bearing fluorene–bisphenol and two ortho-linked diaryl-substituted imidazole rings were synthesized by the catalytic reduction of the nitro groups of compound (II), 9,9-bis{4-[2-(4,5-diphenylimidazol-2-yl)-4-nitrophenoxy]phenyl}fluorene, by using hydrazine monohydrate in the presence of Pd/C. Compound (II) was synthesized by the nucleophilic chloro displacement reaction of the synthesized 2-(2-chloro-5-nitrophenyl)-4,5-diphenyl-1H-imidazole with 9,9-bis(4-hydroxyphenyl)fluorene in refluxing DMAc in the presence of potassium carbonate. This diamine was condensed directly with aliphatic and aromatic diacids via the Yamazaki–Higashi phosphorylation method in the presence of triphenylphosphite (TPP), pyridine (Py) and halide salt to give high molecular polyamides (PAs). The synthesized PAs were obtained in quantitative yields with inherent viscosities between 0.51 and 0.76 dL g?1. The structures of diamine and PAs were characterized by elemental analysis, FT-IR and NMR spectroscopy, and properties of PAs were investigated by using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and UV–visible and fluorescence spectroscopy. The PAs showed good solubility in aprotic and polar organic solvents, with high thermal stability exhibiting the glass transition temperatures (Tgs) and 10% weight loss temperatures (T10%) in the range of 226–330 °C and 400–466 °C in air, respectively, and fluorescence emission with maximum wavelengths (λem) in the range of 417–473 nm with quantum yields (Φf) of 9–35%. Two of these polymers together with compounds (II) and (III) were also screened for antibacterial activity against Gram positive and Gram negative bacteria.  相似文献   

11.
The preparation of new compounds, 1,1‐bis[4‐(2‐(4,4‐dimethyl‐1,3‐oxazolyl))phenyl]ethanol and a new symmetrically disubstituted 1,1‐diphenylethylene derivative, 1,1‐bis[4‐(2‐(4,4‐dimethyl‐1,3‐oxazolyl))phenyl]ethylene, is described. 1,1‐Bis[4‐(2‐(4,4‐dimethyl‐1,3‐oxazolyl))phenyl]ethylene was utilized as a dioxazolyl initiator precursor for the polymerization of styrene by atom transfer radical polymerization (ATRP) methods to produce α‐bis(oxazolyl) polystyrene. The kinetic study of the polymerization process indicated that the free radical polymerization reaction for the preparation of α‐bis(oxazolyl) polystyrene follows first‐order rate kinetics with respect to monomer consumption. α,ω‐Tetrakis(oxazolyl) polystyrene was prepared by a new, in situ, controlled/living, post‐ATRP chain‐end‐functionalization reaction which involves the direct addition of 1,1‐bis[4‐(2‐(4,4‐dimethyl‐1,3‐oxazolyl))phenyl]ethylene to the ω‐terminus of the α‐bis(oxazolyl) polystyrene derivative, without the isolation and purification of the polymeric precursor. α‐Bis(carboxyl) and α,ω‐tetrakis(carboxyl) polystyrene derivatives were obtained by the quantitative chemical transformation of the oxazoline groups of the respective aromatic oxazolyl chain‐end‐functionalized polystyrene derivatives to the aromatic carboxyl groups. The organic precursor compounds, the dioxazolyl‐functionalized 1,1‐diphenylethylene derivative and the functionalized polymers were characterized using 1H NMR and 13C NMR spectrometry and Fourier transform infrared spectroscopy, size‐exclusion and thin‐layer chromatography and non‐aqueous titration measurements. © 2014 Society of Chemical Industry  相似文献   

12.
Aromatic polyesters are of considerable interest because of their excellent mechanical properties, chemical resistance and thermal stability. However, most aromatic polyesters are difficult to process due to their high glass transition temperatures coupled with their insolubility in common organic solvents. The present article describes a series of organosoluble polyesters and copolyesters based on 1,1,1‐[bis(4‐hydroxyphenyl)‐4′‐pentadecylphenyl]ethane. A series of new aromatic polyesters containing pendant pentadecyl chains was synthesized by interfacial polycondensation of 1,1,1‐[bis(4‐hydroxyphenyl)‐4′‐pentadecylphenyl]ethane with terephthalic acid chloride (TPC), isophthalic acid chloride (IPC) and a mixture of TPC and IPC. A series of copolyesters was synthesized from 4,4′‐isopropylidenediphenol with TPC by incorporating 1,1,1‐[bis(4‐hydroxyphenyl)‐4′‐pentadecylphenyl]ethane as a comonomer. Inherent viscosities of the polyesters and copolyesters were in the range 0.72–1.65 dL g?1 and number‐average molecular weights were in the range 18 170–87 220. The polyesters and copolyesters containing pendant pentadecyl chains dissolved readily in organic solvents such as chloroform, dichloromethane, pyridine and m‐cresol and could be cast into transparent, flexible and apparently tough films. Wide‐angle X‐ray diffraction data revealed the amorphous nature of the polyesters and copolyesters. The formation of loosely developed layered structure was observed due to the packing of pendant pentadecyl chains. The temperature at 10% weight loss, determined using thermogravimetric analysis in nitrogen atmosphere, of the polyesters and copolyesters containing pendant pentadecyl chains was in the range 400–460 °C. The polyesters and copolyesters exhibited glass transition temperatures in the range 63–82 °C and 177–183 °C, respectively. Copyright © 2010 Society of Chemical Industry  相似文献   

13.
2,2′‐Position aryl‐substituted tetracarboxylic dianhydrides including 2,2′‐bis(biphenyl)‐4,4′,5,5′‐biphenyl tetracarboxylic dianhydride and 2,2′‐bis[4‐(naphthalen‐1‐yl)phenyl)]‐4,4′,5,5′‐biphenyl tetracarboxylic dianhydride were synthesized. A new series of aromatic polyimides (PIs) were synthesized via a two‐step procedure from 3,3′,4,4′‐biphenyl tetracarboxylic dianhydride and the newly synthesized tetracarboxylic dianhydrides monomers reacting with 2,2′‐bis[4′‐(3″,4″,5″‐trifluorophenyl)phenyl]‐4,4′‐biphenyl diamine. The resulting polymers exhibited excellent organosolubility and thermal properties associated with Tg at 264 °C and high initial thermal decomposition temperatures (T5%) exceeding 500 °C in argon. Moreover, the fabricated sandwich structured memory devices of Al/PI‐a/ITO was determined to present a flash‐type memory behaviour, while Al/PI‐b/ITO and Al/PI‐c/ITO exhibited write‐once read‐many‐times memory capability with different threshold voltages. In addition, Al/polymer/ITO devices showed high stability under a constant stress or continuous read pulse voltage of ? 1.0 V. Copyright © 2011 Society of Chemical Industry  相似文献   

14.
Two new bisfluoro monomers 9,10‐bis‐(4‐fluoro‐3‐trifluoromethylphenyl) anthracene and 2,7‐bis‐(4‐fluoro‐3‐trifluoromethylphenyl) fluorene have been synthesized by the cross‐coupling reaction of 2‐fluoro‐3‐trifluoromethyl phenyl boronic acid with 9,10‐dibromo anthracene and 2,7‐dibromo fluorine, respectively. These two bisfluoro compounds were used to prepare several poly(arylene ether)s by aromatic nucleophilic displacement of fluorine with various bisphenols; such as bisphenol‐A, bisphenol‐6F, bishydroxy biphenyl, and 9,9‐bis‐(4‐hydroxyphenyl)‐fluorene. The products obtained by displacement of the fluorine atoms exhibits weight‐average molar masses up to 1.5 ×105 g mol?1 and number average molecular weight up to 6.8 × 104 g mol?1 in GPC. These poly(arylene ether)s show very high thermal stability even up to 490°C for 5% weight loss occurring at this temperature in TGA in synthetic air and showed glass transition temperature observed up to 310°C. All the polymers are soluble in a wide range of organic solvents, e.g., CHCl3, THF, NMP, and DMF. Films cast from DMF solution are brittle in nature. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007  相似文献   

15.
Ferrocene‐substituted conducting polymer namely poly(trans‐1‐(4‐methyl‐3′‐thienyl)‐2‐(ferrocenyl)ethene‐co‐3,4‐ethylenedioxythiophene) [P(MTFE‐co‐EDOT)] was synthesized and its electrochromic properties were studied. Monomer, MTFE, was obtained using 2‐(ferrocenyl)ethene and 3‐methyl‐4‐bromothiophene. The structure of monomer was determined via Fourier transform infrared spectroscopy (FTIR), 1H‐NMR, and 13C‐NMR techniques. The copolymer was synthesized using this monomer and EDOT. The resulting copolymer P(MTFE‐co‐EDOT) was characterized by cyclic voltammetry, FTIR, scanning electron microscopy, atomic force microscopy, and UV–vis spectroscopy. The conductivity measurements of copolymer and PEDOT were accomplished by the four‐probe technique. Although poly(trans‐1‐(4‐methyl‐3′‐thienyl)‐2‐(ferrocenyl)ethene) [P(MTFE)] reveals no electrochromic activity, its copolymer with EDOT has two different colors (violet and gray). Band gap (Eg) and λmax of P(MTFE‐co‐EDOT) were determined. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

16.
Aromatic polyetherimides were synthesized from a fluorine containing aromatic carboxylic acid dianhydride, 2,2‐bis[4‐(3,4‐dicarboxyphenoxy)phenyl]hexafluoropropane dianhydride (6F‐BABPA) and five typical aromatic diamines including 1,1‐bis(4‐aminophenyl)‐1‐phenyl‐2,2,2‐trifluoroethane (3F‐DAM) by two‐step procedures—amidation to polyamic acids (PAA), followed by thermal imidization of PAA. The chemical and physical properties of the newly prepared polyetherimides (PEI) were compared in terms of their chemical structures, inherent viscosities, mechanical, and thermal properties. All polyetherimides were well soluble in common organic solvents such as N‐methyl‐2‐pyrolidone (NMP), N,N‐dimethylformamide (DMF), N,N‐dimethylacetamide (DMAc), pyridine, and methylene chloride. A PEI prepared from 6F‐BABPA/3F‐DAM was especially easily dissolved in NMP. The glass transition temperature (Tg) range of the obtained PEI was 209–257°C. The dielectric constants and refractive index were 2.8–3.2 and 1.61–1.56, respectively. The polyetherimide, 6F‐BABPA/BAPP, with a low fluorine content (11.4% fluorine content), has 0.99% water absorption, whereas the polyetherimide, 6F‐BABPA/4‐BDAP, having a high fluorine content (26.0% fluorine content) showed 0.35% of water absorption. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 76: 249–257, 2000  相似文献   

17.
Binary copolymerization of 4‐methyl‐1,3‐pentadiene (4MPD) with styrene, butadiene and isoprene promoted by the titanium complex dichloro{1,4‐dithiabutanediyl‐2,2′‐bis[4,6‐bis(2‐phenyl‐2‐propyl)phenoxy]}titanium activated by methylaluminoxane is reported. All the copolymers are obtained in a wide range of composition and the molecular weight distributions obtained from gel permeation chromatographic analysis of the copolymers are coherent with the materials being copolymeric in nature. The copolymer microstructure was fully elucidated by means of 1H NMR and 13C NMR spectroscopy. Differential scanning calorimetry shows an increase of glass transition temperature (Tg) with the amount of 4MPD in the copolymers with butadiene and isoprene, while in the copolymers with styrene Tg is increased on increasing the amount of styrene. © 2016 Society of Chemical Industry  相似文献   

18.
Three types of amino‐functionalized calixarenes, i.e. the diaminocalix[4]arenes 5,17‐diaminomethyl‐25,26,27,28‐tetrapropoxycalix[4]arene, 25,27‐diaminoethoxy‐26,28‐dihydroxycalix[4]arene and 5,11,17,23‐tetra‐tert‐butyl‐25,27‐diaminoethoxy‐26,28‐dihydroxycalix[4]arene, were synthesized and incorporated as comonomers into the backbones of aromatic polyimides. As a first step, polyimide precursors (poly(amic acid)s) were prepared by condensation reaction of diamine with dianhydride at the stoichiometric ratio. The diamine component was composed of synthesized diaminocalix[4]arene and commercial 4,4′‐oxydianiline combined in various molar ratios. The dianhydride used was 4,4′‐oxydiphthalic anhydride. The poly(amic acid)s were characterized using intrinsic viscosity measurements and their chemical composition was determined using 1H NMR spectroscopy. The precursors were then transformed into the polyimides using a thermal treatment. Thermal and dynamic mechanical behaviour, wide‐angle X‐ray diffraction and solubility of the resulting polyimide films in selected solvents were evaluated. The structure–property relationship of the novel types of synthesized polyimides is discussed in terms of the calixarene monomer used and the fraction of it incorporated into the polymer backbone. Copyright © 2010 Society of Chemical Industry  相似文献   

19.
A CF3‐containing diamine, 4,4′‐bis(4‐amino‐2‐trifluoromethylphenoxy)benzophenone ( 2 ), was synthesized from 4,4′‐dihydroxybenzophenone and 2‐chloro‐5‐nitrobenzotrifluoride. Imide‐containing diacids ( 3 and 5Ba – 5Bg ) were prepared by the condensation reaction of aromatic diamines and trimellitic anhydride. Then, two series of novel soluble aromatic poly(amide imide)s (PAIs; 6Aa – 6Ak and 6Ba – 6Bg ) were synthesized from a diamine ( 4Aa – 4Ak or 2 ) with the imide‐containing diacids ( 3 and 5Ba – 5Bg ) via direct polycondensation with triphenyl phosphate and pyridine. The aromatic PAIs had inherent viscosities of 0.74–1.76 dL/g. All of the synthesized polymers showed excellent solubility in amide‐type solvents, such as N‐methyl‐2‐pyrrolidone and N,N‐dimethylacetamide (DMAc), and afforded transparent and tough films by DMAc solvent casting. These polymer films had tensile strengths of 90–113 MPa, elongations at break of 8–15%, and initial moduli of 2.0–2.9 GPa. The glass‐transition temperatures of the aromatic PAIs were in the range 242–279°C. They had 10% weight losses at temperatures above 500°C and showed excellent thermal stabilities. The 6B series exhibited less coloring and showed lower yellowness index values than the corresponding 6A series. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102:3641–3653, 2006  相似文献   

20.
A new‐type of dicarboxylic acid was synthesized from the reaction of 2,5‐bis(4‐aminobenzylidene)cyclopentanone with trimellitic anhydride in a solution of glacial acetic acid/pyridine (Py) at refluxing temperature. Six novel heat resistance poly(amide‐imide)s (PAIs) with good inherent viscosities were synthesized, from the direct polycondensation reaction of N,N′‐[2,5‐bis(4‐aminobenzylidene)cyclopentanone]bistrimellitimide acid with several aromatic diamines, by two different methods such as direct polycondensation in a medium consisting of N‐methyl‐2‐pyrrolidone (NMP)/triphenyl phosphite (TPP)/calcium chloride (CaCl2)/pyridine (Py) and direct polycondensation in a p‐toluene sulfonyl chloride (tosyl chloride, TsCl)/pyridine (Py)/N,N‐dimethylformamide (DMF) system. All of the above polymers were fully characterized by 1H NMR, FTIR, elemental analysis, inherent viscosity, solubility tests, UV‐vis spectroscopy, differential scanning calorimeter (DSC), thermogravimetric analysis (TGA), and derivative of thermaogravimetric (DTG). The resulted poly(amide‐imide)s (PAIs) have showed admirable good inherent viscosities, thermal stability, and solubility. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

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