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1.
Aromatic polyamides and polythioamides with pendent chlorobenzylidine rings were synthesized through direct polycondenzation of 2‐(p‐chlorobenzalimino) terephthalic acid with the diamines 4,4′‐oxidianiline (1a), 4,4′‐methylenediamide (1b), 4,4′‐diaminodiphenyl sulfone (1c), and thioamines 4,4′‐(bisthiourea) diphenyl ether (3a), 4,4′‐(bisthiourea) diphenyl methane (3b), 4,4′‐(bisthiourea) diphenyl sulfone (3c), respectively, in DMF using P(OPh)3/pyridine. The polymers were precipitated using water as nonsolvent. FTIR and 1H‐NMR spectroscopic analysis was used to characterize the monomers and polymers. Representative polyamides and polythioamides were used for the removal of heavy metal ions such as Pb(II), Cd(II), Cu(II), and Cr(III) from aqueous solutions. The effects of pH, contact time, and initial concentration on the uptake of metal ions have been investigated. The adsorption capacities under competitive conditions were in the order Pb (II) > Cu (II) > Cr (III) > Cd (II). The adsorbed ions were eluted by treatment with 2N HCl, and the activities of the polymers are retained after fourth regeneration. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

2.
A new interesting class of polyurea derivatives 5 a‐c was synthesized using solution polycondensation technique by the interaction of 1 mol of 4,4′‐bis(2″‐aminothiazol‐4″‐yl)diphenyl ether monomer 3 with 1 mol of diisocyanate compounds in pyridine. The model compound 4 was synthesized by the interaction of 1 mol of monomers 3 with 2 mol of phenylisocyanate in pyridine, and the structure was confirmed by correct elemental and spectral analyses. The resulting polymers were characterized by elemental and spectral analyses besides solubility and viscometry measurements. The thermal properties of those polymers were evaluated by TGA, DTG, and DTA measurements and correlated to their structural units. In addition, the morphological properties of a selected example were tested by SEM, and the electrical properties of these polymers were measured. On the other hand, the corrosion inhibition properties of selected example of polyurea derivatives were carried out on steel in 0.5M H2SO4 at 40°C giving cathodic inhibition. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

3.
A series of amorphous fluoro‐polyetherimides based on 2,2′‐bis(3,4‐dicarboxyphenyl) hexafluropropane dianhydride (6FDA) and di‐ether‐containing diamines 4,4′‐bis(3‐aminophenoxy)diphenyl sulfone (m‐SED), 4,4′‐bis(4‐aminophenoxy)diphenyl sulfone (p‐SED), 4,4′‐bis(4‐aminophenoxy)diphenyl propane (BPADE) were synthesized. These melt processable polyetherimide polymers from p‐SED and BPADE showed excellent electrical properties. The dielectric constants, 2.74 and 2.65 at 10 MHz respectively, are lower than commercially available polyetherimide ULTEM® 1000, and polyimide Kapton® H films. In addition, we found that trifluoromethyl groups‐containing polyimides not only show extraordinary electrical properties, but they also exhibit excellent long‐term thermo‐oxidative stability and reduced water absorption relative to non‐fluorinated polyimides. The weight retention of these fluoro‐polyetherimides at 315°C for 300 h in air varies from 93% to 98%. Whereas, their moisture absorption at 100 RH at 50°C was in the range of 0.3% to 1.05%, which is much lower than those of Ultem 1000 and Kapton H. In the case of fluoro‐polyetherimides from p‐SED and m‐SED (para and meta isomers) diamines with ‘ether’ and sulfonyl (‐SO2‐) spacer groups, the d‐spacing and Tg values decreased from 4.72Å to 4.56Å and 293°C to 244°C respectively. Similarly, the transparency of these polymer films (in the range of 80% to 90%) at 500 nm solar wavelength was higher than Ultem 1000 and Kapton H.  相似文献   

4.
Two series of isomers containing pyridine and sulfur unit aromatic diamine monomers, 4,4′‐bis(5‐amino‐2‐pyridinylsulfanyl)diphenyl sulfide ( 2a ), 4,4′‐bis(6‐amino‐3‐pyridinylsulfanyl)diphenyl sulfide ( 2b ) and 4,4′‐bis(5‐amino‐6‐methyl‐2‐pyridinylsulfanyl)diphenyl sulfide ( 2c ), 4,4′‐bis(5‐amino‐4‐methyl‐2‐pyridinylsulfanyl)diphenyl sulfide ( 2d ), were designed and synthesized. Aimed at clarifying the structure–property relationships of pyridine‐ and sulfur‐containing high refractive polymers, 2a was polymerized with various dianhydrides to prepare polyimides PI ‐1?PI ‐7 and 2b , 2c , 2d were reacted with 4,4′‐[p ‐thiobis(phenylenesulfanyl)]diphthalic anhydride to prepare polyimides PI ‐8?PI ‐10. The polyimides showed excellent optical properties with average refractive indices ranging from 1.7006 to 1.7620 and birefringence as low as 0.0056. Meanwhile, comparative studies on their properties including solubility, thermal and mechanical, and optical transparency properties were performed. Some property differences of the isomers caused by the sequence changes were found. © 2017 Society of Chemical Industry  相似文献   

5.
The synthesis of new methacrylate‐based, curable macromonomers, 4,4′‐bis[2‐hydroxy‐3‐aminopropylmethacrylate] diphenyl ether (BHAPE) and 4,4′‐bis[2‐hydroxy‐3‐aminopropylmethacrylate] diphenyl methane (BHAPM), is reported. BHAPE and BHAPM were prepared by the reaction of glycidyl methacrylate (GMA) with 4,4′‐diaminodiphenyl ether and 4,4′‐diaminodiphenyl methane, respectively. The progress of the reaction was monitored by thin‐layer chromatography (TLC), and the structure of the monomers was characterized by Fourier transform infrared (FTIR) and 1H‐NMR spectroscopy. Thermal curing of the monomers was conducted in a differential scanning calorimeter (DSC) with peroxide as the initiator. Thermal curing of the monomers showed the highest rate at 100°C with the activation energy value in the range 80–90 kJ distilled/mol. The water absorption properties of the cured samples in water, acidic, and basic solutions were studied. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

6.
Low-molecular-weight poly(arylene keto amines) were prepared from the polymerization of 4,4-bis(chloroacetyl)diphenyl ether, 4, 4′-bis(bromoacetyl) diphenyl ether, and 4,4′-bis(2-bromopropionyl) diphenyl ether with piperazine, 4, 4′-trimethylenedipiperidine, and N, N′-dimethyl-1,3-propanediamine. These film-forming polymers and suitable monomeric model compounds were found to be degraded by photolysis. The poly(keto amines) resisted degradation by the fungi As-pergillus niger and Aspergillus flavus.  相似文献   

7.
A new diamine, 2,2′‐bis(3,4,5‐trifluorophenyl)‐4,4′‐diaminodiphenyl ether (FPAPE) was synthesized through the Suzuki coupling reaction of 2,2′‐diiodo‐4,4′‐dinitrodiphenyl ether with 3,4,5‐trifluorophenylboronic acid to produce 2,2′‐bis(3,4,5‐trifluorophenyl)‐4,4′‐dinitrodiphenyl ether (FPNPE), followed by palladium‐catalyzed hydrazine reduction of FPNPE. FPAPE was then utilized to prepare a novel class of highly fluorinated all‐aromatic poly(ether‐imide)s. The chemical structure of the resulting polymers is well confirmed by infrared and nuclear magnetic resonance spectroscopic methods. Limiting viscosity numbers of the polymer solutions at 25 °C were measured through the extrapolation of the concentrations used to zero. Mn and Mw of these polymers were about 10 000 and 25 000 g mol?1, respectively. The polymers showed a good film‐forming ability, and some characteristics of their thin films including color and flexibility were investigated qualitatively. An excellent solubility in polar organic solvents was observed. X‐ray diffraction measurements showed that the fluoro‐containing polymers have a nearly amorphous nature. The resulting polymers had Tg values higher than 340 °C and were thermally stable, with 10% weight loss temperatures being recorded above 550 °C. Based on the results obtained, FPAPE can be considered as a promising design to prepare the related high performance polymeric materials. Copyright © 2011 Society of Chemical Industry  相似文献   

8.
Poly(keto esters) were prepared from 4,4′-bis(chloroacetyl) diphenyl ether, 4,4′-bis(bromoacetyl)diphenyl ether, and 4,4′-bis(2-bromopropionyl)-diphenyl ether and aliphatic diacids of 6, 8, 9, 10, and 12 carbon atoms. Low-molecular-weight polymers were found to support the growth of Aspergillus niger and Aspergillus flavus. Introduction of methyl group to the polymer chain decreased the susceptibility of the polymers to fungal attack. Although monomeric model compounds were found to undergo photodegradation the poly(keto esters) underwent mostly crosslinking when irradiated with UV light.  相似文献   

9.
Three series of isomeric poly(amide imide)s (series III, IV, and V) were synthesized by the direct polycondensation of 2,2′‐bis(4‐aminophenoxy)biphenyl (2,2′‐BAPB), 4,4′‐bis(4‐aminophenoxy)biphenyl (4,4′‐BAPB), or their equimolar mixture (2,2′‐BAPB/4,4′‐BAPB = 1/1) with 12 diimide diacids and with triphenyl phosphite and pyridine as condensing agents. A comparison of the physical properties of these three series was also made. The inherent viscosities of series III, IV, and V were 0.25–0.84, 0.25–1.52, and 0.43–1.30 dL g?1, respectively. Most of the series III polymers showed better solubility because of the non‐para structure, with the solubility order found to be III > V > IV. According to X‐ray diffraction patterns, the amorphous poly(amide imide)s had excellent solubility, whereas the crystalline polymers were less soluble. All the soluble polymers afforded transparent, flexible, and tough films, which had tensile strengths of 57–104 MPa, elongations at break of 3–20%, and initial moduli of 2.05–2.86 GPa. The glass‐transition temperatures (measured by differential scanning calorimetry) were highest for series IV, which contained the rigid 4,4′‐biphenyl units (254–299°C); copolymer series V ranked second (237–277°C), and series III, with crank 2,2′‐biphenyl structures, had the lowest values (227–268°C). The 10% weight‐loss temperatures (measured by thermogravimetric analysis) were close to one another, ranging from 527 to 574°C in nitrogen and from 472 to 543°C in air. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2763–2774, 2002  相似文献   

10.
New linear polyurethanes derived from 4,4′‐bis(6‐hydroxyhexylthio)diphenyl ether and methylene bis(4‐phenyl isocyanate) were synthesized by either melt or solution polymerization with a strictly equimolar ratio of the monomers. In the solution method, good results were obtained with the aprotic solvent N,N‐dimethylformamide at an approximately 20 wt % concentration of the monomers, with dibutyltin dilaurate as a catalyst, the process being conducted at 90–100°C for 4 h. The basic physicochemical properties of the polymers were investigated with thermogravimetric analysis and differential scanning calorimetry. The molecular weight distribution was determined by gel permeation chromatography. Shore hardness and tensile test results were also examined. The structures of the resulting products were confirmed with elemental analysis, Fourier transform infrared, and X‐ray diffractometry. The properties of the copolyurethanes, containing various amounts of poly(oxytetramethylene) diol (~1000) or polycaprolactone diol (~1250) and synthesized under the conditions for the nonsegmented polyurethanes, were also examined. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 380–388, 2003  相似文献   

11.
New monomers, 4,4′‐bis(4‐phenoxybenzoyl)diphenyl (BPOBDP) and N,N′‐bis(4‐phenoxybenzoyl)?4,4′‐diaminodiphenyl ether (BPBDAE), were conveniently synthesized via simple synthetic procedures from readily available materials. Novel copolymers of poly(ether ketone diphenyl ketone ether ketone ketone) (PEKDKEKK) and poly(ether amide ether amide ether ketone ketone) (PEAEAEKK) were synthesized by electrophilic Friedel‐Crafts solution copolycondensation of isophthaloyl chloride (IPC) with a mixture of BPOBDP and BPBDAE, over a wide range of BPOBDP/BPBDAE molar ratios, in the presence of anhydrous AlCl3 and N‐methylpyrrolidone (NMP) in 1,2‐dichloroethane (DCE). The copolymers obtained were characterized by different physico‐chemical techniques. The copolymers with 10–40 mol% BPBDAE are semicrystalline and had remarkably increased Tgs over commercially available PEEK and PEKK due to the incorporation of amide and diphenyl linkages in the main chains. The copolymers IV and V with 30–40 mol% BPBDAE had not only high Tgs of 185–188°C, but also moderate Tms of 326–330°C, having good potential for the melt processing. The copolymers IV and V had tensile strengths of 101.7–102.3 MPa, Young's moduli of 2.19–2.42 GPa, and elongations at break of 13.2–16.6% and exhibited high thermal stability and excellent resistance to organic solvents. POLYM. ENG. SCI., 54:1757–1764, 2014. © 2013 Society of Plastics Engineers  相似文献   

12.
4,4′‐Bis(4‐phenoxybenzoyl)diphenyl was prepared by the Friedel–Crafts reaction of 4‐bromobenzoyl chloride and diphenyl followed by condensation with potassium phenoxide. Novel aromatic poly(ether ketone diphenyl ketone ether ketone ketone)s were obtained by the electrophilic Friedel–Crafts solution copolycondensation of 4,4′‐bis(4‐phenoxybenzoyl)diphenyl with a mixture of isophthaloyl chloride and terephthaloyl chloride over a wide range of isophthaloyl chloride/terephthaloyl chloride molar ratios in the presence of anhydrous aluminum chloride and N‐methylpyrrolidone in 1,2‐dichloroethane. The influence of the reaction conditions on the preparation of the copolymers was examined. The copolymers were characterized with different physicochemical techniques. Because of the incorporation of diphenyl, the resulting copolymers exhibited outstanding thermal stability. The glass‐transition temperatures were above 174°C, the melting temperatures were above 342°C, and the 5% weight loss temperatures were above 544°C in nitrogen. All these copolymers were semicrystalline and insoluble in organic solvents. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

13.
In order to obtain polyamides with enhanced solubility and processability, as well as good mechanical and thermal properties, several novel polyamides containing sulfone‐ether linkages and xanthene cardo groups based on a new diamine monomer, 9,9‐bis[4‐(4‐aminophenoxy)phenyl]xanthene (BAPX), were investigated. The BAPX monomer was synthesized via a two‐step process consisting of an aromatic nucleophilic substitution reaction of readily available 4‐chloronitrobenzene with 9,9‐bis(4‐hydroxyphenyl)xanthene in the presence of potassium carbonate in N,N‐dimethylformamide, followed by catalytic reduction with hydrazine and Pd/C. Four novel aromatic polyamides containing sulfone‐ether linkages and xanthene cardo groups with inherent viscosities between 0.98 and 1.22 dL g?1 were prepared by low‐temperature polycondensation of BAPX with 4,4′‐sulfonyldibenzoyl chloride, 4,4′‐[sulfonyl‐bis(4‐phenyleneoxy)]dibenzoyl chloride, 3,3′‐[sulfonyl‐bis(4‐phenyleneoxy)]dibenzoyl chloride and 4,4′‐[sulfonyl‐bis(2,6‐dimethyl‐1,4‐phenyleneoxy)]dibenzoyl chloride in N,N‐dimethylacetamide (DMAc) solution containing pyridine. All these new polyamides were amorphous and readily soluble in various polar solvents such as DMAc and N‐methylpyrrolidone. These polymers showed relatively high glass transition temperatures in the range 238–298 °C, almost no weight loss up to 450 °C in air or nitrogen atmosphere, decomposition temperatures at 10% weight loss ranging from 472 to 523 °C and 465 to 512 °C in nitrogen and air, respectively, and char yields at 800 °C in nitrogen higher than 50 wt%. Transparent, flexible and tough films of these polymers cast from DMAc solution exhibited tensile strengths ranging from 78 to 87 MPa, elongations at break from 9 to 13% and initial moduli from 1.7 to 2.2 GPa. Primary characterization of these novel polyamides shows that they might serve as new candidates for processable high‐performance polymeric materials. Copyright © 2010 Society of Chemical Industry  相似文献   

14.
A new method of synthesis of poly(ether carbonate)s based on interchange reactions of dihydroxy compounds with alkylene and arylene diphenyl dicarbonates containing ether group was presented. The diphenyl dicarbonate monomers were prepared from phenyl chloroformate and dihydroxy compounds containing ether group (e.g., diethylene glycol, bis(2‐hydroxyethyl ether) of bisphenol A, and 4,4′‐oxydiphenol). The process consisted of a precondensation step under a stream of dry argon followed by a melt polycondensation at 230 or at 250°C under vacuum. Four series of poly(ether carbonate)s were prepared using this approach. Using alkylene and arylene diphenyl dicarbonate‐containing ether groups as monomers, the polycondensation reaction with dihydroxy compounds led to the formation of poly(ether carbonate)s having inherent viscosity values up to 0.56 dL/g and high thermal stability. The glass transition temperature values of polycarbonates were in the range 7–122°C. The polymers were characterized by inherent viscosity and spectroscopic (Fourier transform infrared spectroscopy and 1H‐NMR and 13C‐NMR) and thermal (differential scanning calorimeteric and thermogravimetric) methods. This approach may permit the use of diphenyl dicarbonates containing other organic functional groups for the synthesis of polycarbonates containing those groups. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

15.
Two series of heterocyclic aromatic polymers were synthesized from 4,4′‐(4,4′‐isopropylidenediphenoxy)bis(phthaltic anhydride) and 2,2′‐bis(3,4‐dicarboxyphenyl)hexafluoropropane dianhydride by two‐step method. The inherent viscosities were in the range of 24–45 cm3/g. The effects of the rigid benzoxazole group in the backbone of copolymer on the thermal, mechanical, and physical properties were investigated. These polymers exhibit good thermal stability. The temperatures of 5% weight loss (T5) of these polymers are in the range of 403–530°C in air and 425–539°C in nitrogen. The chard yields of these polymers are in the range of 15–24% in air and 54–61% in nitrogen. These polymers also have high glass‐transition temperatures and a low coefficient of thermal expansion and good mechanical properties. The poly(benzoxazol imide) has a higher tensile strength and modulus than those of neat polyimide. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

16.
A novel monomer of tetrachloroterephthaloyl chloride (TCTPC) was prepared by the chlorination of terephthaloyl chloride catalyzed by ferric chloride at 175–180°C for 10 h and confirmed by FTIR, MS, and elemental analysis. Five new polychloro substituted poly(aryl ether ketone sulfone)s (PEKSs) with inherent viscosities of 0.68–0.75 dL/g have been prepared from 4,4′‐diphenoxydiphenylsulfone, 4,4′‐bis(2‐methylphenoxy) diphenylsulfone, 4,4′‐bis(3‐methylph‐enoxy)diphenylsulfone, 4,4′‐bis(2,6‐dimethylphenoxy)diphenylsulfone, and 4,4′‐bis(1‐naphthoxy)‐diphenylsulfone with TCTPC by electrophilic Friedel‐Crafts acylation in the presence of DMF with anhydrous AlCl3 as a catalyst in 1,2‐dichloroethane, respectively. These polymers having weight–average molecular weight in the range of 76,600–83,900 are all amorphous and show high glass transition temperatures ranging from 213 to 250°C, the 5% weight loss temperature over 450°C, high char yields of 60–67% at 700°C in nitrogen and good solubility in CHCl3 and polar solvents such as DMF, DMSO, and NMP at room temperature. All the polymers formed transparent, strong, and flexible films, with tensile strengths of 85.1–90.8 MPa, Young's moduli of 2.52–3.24 GPa, and elongations at break of 21.2–27.2%. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

17.
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   

18.
A new indane containing unsymmetrical diamine monomer ( 3 ) was synthesized. This diamine monomer leads to a number of novel semifluorinated poly (ether imide)s when reacted with different commercially available dianhydrides like benzene‐1,2,4,5‐tetracarboxylic dianhydride (PMDA), benzophenone‐3,3′, 4,4′‐tetracarboxylic dianhydride (BTDA), 4,4′‐(hexafluoro‐isopropylidene)diphthalic anhydride (6FDA), 4,4′‐oxydiphthalic anhydride (ODPA), and 4,4′‐(4,4′‐Isopropylidenediphenoxy)bis(phthalic anhydride) (BPADA) by thermal imidization route. All the poly(ether imide)s showed excellent solubility in several organic solvents such as N‐methylpyrrolidone (NMP), N,N‐dimethylformamide (DMF), N,N‐dimethylacetamide (DMAc), tetrahydrofuran (THF), chloroform (CHCl3) and dichloromethane (DCM) at room temperature. These light yellow poly (ether imide)s showed very low water absorption (0.19–0.30%) and very good optical transparency. Wide angle X‐ray diffraction measurements revealed that these polymers were amorphous in nature. The polymers exhibited high thermal stability up to 526°C in nitrogen with 5% weight loss, and high glass transition temperature up to 265°C. The polymers exhibited high tensile strength up to 85 MPa, modulus up to 2.5 GPa and elongation at break up to 38%, depending on the exact polymer structure. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

19.
A new category of linear poly(ether-ketone)s IVa–d and copoly(ether-ketone)s Va–f containing diarylidenecycloalkanone moieties in the main chain has been synthesized by solution polycondensation of 4,4′-bis (chloroacetyl)diphenylether I , with different phenoxides of diarylidenecycloalkanones IIa–d . The model compound III was synthesized from the monomer I with sodium phenoxide in DMF and K2CO3, and its structure was confirmed by elemental and spectral analyses. The resulting polyketones and copolyketones were characterized by elemental and spectral analyses, beside solubility and viscometry measurements. The thermal properties of those polymers were evaluated by TGA and DTA measurements and correlated to their structural units. X-ray analysis showed that polymers having some degree of crystallinity in the region 2θ = 5–60°. In addition, the biological screening and morphological properties of selected examples of the polymers were tested. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

20.
A novel dianhydride, trans‐1,2‐bis(3,4‐dicarboxyphenoxy)cyclohexane dianhydride (1,2‐CHDPA), was prepared through aromatic nucleophilic substitution reaction of 4‐nitrophthalonitrile with trans‐cyclohexane‐1,2‐diol followed by hydrolysis and dehydration. A series of polyimides (PIs) were synthesized from one‐step polycondensation of 1,2‐CHDPA with several aromatic diamines, such as 2,2′‐bis(trifluoromethyl)biphenyl‐4,4′‐diamine (TFDB), bis(4‐amino‐2‐trifluoromethylphenyl)ether (TFODA), 4,4′‐diaminodiphenyl ether (ODA), 1,4‐bis(4‐aminophenoxy)benzene (TPEQ), 4,4′‐(1,3‐phenylenedioxy)dianiline (TPER), 2,2′‐bis[4‐(3‐aminodiphenoxy)phenyl]sulfone (m‐BAPS), and 2,2′‐bis[4‐(4‐amino‐2‐trifluoromethylphenoxy)phenyl]sulfone (6F‐BAPS). The glass transition temperatures (Tgs) of the polymers were higher than 198°C, and the 5% weight loss temperatures (Td5%s) were in the range of 424–445°C in nitrogen and 415–430°C in air, respectively. All the PIs were endowed with high solubility in common organic solvents and could be cast into tough and flexible films, which exhibited good mechanical properties with tensile strengths of 76–105 MPa, elongations at break of 4.7–7.6%, and tensile moduli of 1.9–2.6 GPa. In particular, the PI films showed excellent optical transparency in the visible region with the cut‐off wavelengths of 369–375 nm owing to the introduction of trans‐1,2‐cyclohexane moiety into the main chain. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42317.  相似文献   

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