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1.
A new positive‐working polyimide having photosensitive o‐nitrobenzyl ester group as side substituent, poly{1,4‐phenyleneoxy‐1,4‐phenylene‐3,6‐di[4‐(o‐nitrobenzyloxy)carbonylphenyl]pyromellitimide} (ODA‐PI‐Nb), was prepared and its aqueous alkali‐developability and photosensitivity were investigated. ODA‐PI‐Nb was synthesized by the esterification reaction of poly[1,4‐phenyleneoxy‐1.4‐phenylene‐3,6‐di(4‐carboxylphenyl)pyromellit imide] (ODA‐PI) with o‐nitrobenzyl bromide in the presence of triethylamine (Et3N). ODA‐PI‐Nb obtained was characterized by FT‐IR and 1H‐NMR spectroscopy. The degree of esterification reaction was found from 1H‐NMR absorption of CH2 proton to be over 95 mol%. Upon photo‐irradiation ODA‐PI‐Nb transformed to the freely aqueous alkali‐soluble ODA‐PI under formation of o‐nitrosobenzaldehyde. The thickness loss of thin ODA‐PI‐Nb films upon post‐baking at 400°C was in the 10–15% range. ODA‐PI‐Nb showed positive‐tone behavior in characteristic sensitivity curve and positive patterns were obtained using a typical lithographic process using aqueous tetramethylammonium hydroxide developer. The patterns with excellent resolution were observed and evaluated by optical microscopy and scanning electron microscopy. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

2.
Several highly soluble polyimides were synthesized from various aromatic tetracarboxylic dianhydrides and an aromatic diamine containing tert‐butyl pendent groups [4,4′‐methylenebis(2‐tert‐butylaniline)]. All the polyimides showed excellent solubility in common solvents such as chloroform, tetrahydrofuran, and dioxane at room temperature. The number‐average molecular weight ranged from 3.6 × 104 to 1.3 × 105 according to gel permeation chromatography relative to a polystyrene standard, and the polydispersity index was between 1.9 and 2.5. The glass‐transition temperatures of the resulting polyimides ranged from 213 to 325 °C, as measured by differential scanning calorimetry, and little weight loss was observed up to 450 °C in N2 by thermogravimetric analysis. These experimental data indicated that the tert‐butyl pendent groups reduced the interactions among polymer chains to improve their solubility in organic solvents without the loss of thermal stability. Transparent and flexible films of these polyimides were obtained via casting from solution. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 40: 229–234, 2002  相似文献   

3.
A novel positive‐working, photosensitive polyimide, poly[1,4‐phenyleneoxy‐1,4‐phenylene‐2,2′‐di(2‐nitrobenzyloxy)benzophenone‐3,3′,4,4′‐tetracarboxdiimide] (OPI‐Nb), developable with an aqueous base was prepared by the o‐nitrobenzylation of a polyimide, poly(1,4‐phenyleneoxy‐1,4‐phenylene‐2,2′‐dihydroxybenzophenone‐3,3′,4,4′‐tetracarboxdiimide) (OPI), derived from 2,2′‐dihydroxy‐3,3′,4,4′‐benzophenonetetracarboxylic dianhydride (DHBA) and 4,4′‐oxydianiline, and it micropatterning properties were investigated. The o‐nitrobenzylation of OPI to OPI‐Nb was conducted with o‐nitrobenzyl bromide in N‐methyl‐2‐pyrrolidinone containing Et3N. The DHBA monomer was synthesized by exhaustive KMnO4 oxidation of bis(2‐dimethoxy‐3,4‐dimethylphenyl)methane obtained by etherification of bis(2‐hydroxy‐3,4‐dimethylphenyl)methane with iodomethane, followed by deprotection of the methoxy groups and cyclodehydration of the obtained 2,2′‐dihydroxy‐3,3′4,4′‐benzophenonetetracarboxylic acid. The intermediate bis(2‐hydroxy‐3,4‐dimethylphenyl)methane was prepared by the condensation of 2,3‐dimethylphenol with paraformaldehyde. The degree of o‐nitrobenzylation was determined to be over 94 mol % from 1H NMR absorption of benzylic CH2 protons. The aromatic OPI was perfectly soluble in a dilute aqueous NaOH solution and tetramethylammonium hydroxide (TMAH), whereas OPI‐Nb was not even swellable in them. In the micropatterning process, OPI‐Nb showed a line‐width resolution of 0.4‐μm and a sensitivity of 5.4 J/cm2 when its thin films were irradiated with 365‐nm light and developed with a 2.38% aqueous TMAH solution at room temperature for 90 s. The thickness loss of OPI‐Nb films measured after postbaking at 350 °C was in the 8–9% range. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 776–788, 2007  相似文献   

4.
4,4′‐Methylenebis(2‐tert‐butylaniline) was synthesized and reacted with pyromellitic dianhydride to produce a polyimide that showed excellent solubility in conventional organic solvents. Solutions of this polyimide could be cast into transparent, flexible and tough films. The number‐average molecular weight, as determined by means of gel permeation chromatography, was 8.9×104 g/mol and the polydispersity index was 1.97. The glass transition temperature was found to be 217°C. The polyimide did not show appreciable decomposition up to 500°C under a nitrogen atmosphere.  相似文献   

5.
A series of polyimides were synthesized from 2,2‐Bis(3,4‐dicarboxyphenyl)hexafluoropropane, 2,2‐bis(3‐amino‐4‐hydroxyphenyl)‐hexafluoropropane, and 4,4′‐oxydianiline by chemical imidization. The effects of the diamine ratios on the properties of the films were evaluated through the study of their thermal, electrical, and morphological properties. All the polymers exhibited better solubility in most of the organic solvents and hence were easily processable. Polyimides with more 2,2‐bis(3‐amino‐4‐hydroxyphenyl)‐hexafluoropropane exhibited better solubility and a low refractive index, which is highly desired for microelectronic applications. The dielectric constant and birefringence were strongly dependent on the fluorine content. With an increase in the fluorine substitution, both the dielectric constant and birefringence decreased. All the polymers exhibited high thermal stability (>400 °C). The absence of crystalline melting in differential scanning calorimetry and broad wide‐angle X‐ray diffraction patterns revealed the amorphous nature of the polymers, which was due to the presence of bulky CF3 groups and hinged ether linkages of the diamine component. The residual stress values decreased with an increase in the 4,4′‐oxydianiline content, and the results were in agreement with the dielectric constant. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 4303–4312, 2004  相似文献   

6.
Four series of polyimides I – VI with pendent triphenylamine (TPA) units having inherent viscosities of 0.44–0.88 dL/g were prepared from four diamines with two commercially available tetracarboxylic dianhydrides via a conventional two‐step procedure that included a ring‐opening polyaddition to give polyamic acids, followed by chemical cyclodehydration. These polymers were amorphous and could afford flexible films. All the polyimides had useful levels of thermal stability associated with high softening temperatures (279–300 °C), 10% weight‐loss temperatures in excess of 505 °C, and char yields at 800 °C in nitrogen higher than 58%. The hole‐transporting and electrochromic properties were examined by electrochemical and spectroelectrochemical methods. Cyclic voltammograms of the polyimide films cast onto an indium‐tin oxide (ITO)‐coated glass substrate exhibited a or two reversible oxidation couples at 0.65–0.78 and 1.00–1.08 V versus Ag/AgCl in acetonitrile solution. The polymer films revealed electrochromic characteristics with a color change from neutral pale yellowish to blue doped form at applied potentials ranging from 0.00 to 1.20 V. The CO2 permeability coefficients (P) and permeability selectivity (P/P) for these polyimide membranes were in the range of 4.73–16.82 barrer and 9.49–51.13, respectively. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7937–7949, 2008  相似文献   

7.
Aromatic polyester, copolyester, and poly(ester-amide-thioester) having pendant carboxyl groups are directly synthesized by the organic phase/water phase interfacial polyconden-sation using low-molecular and polymeric phase transfer catalysts. Spectral analysis of the resulting polymers indicates that the nucleophilicity of salts of phenols to diacid chloride is far higher than that of salts of carboxylic acids and chemoselective esterification occurs in a 100% yield. Even if the polymeric catalyst having amino acid moiety as a nucleophilic group is used in the polycondensation, the polymers do not contain anhydride groups. The polyester can be almost quantitatively converted to polymers with different reactive groups by reacting the pendant carboxyl groups with alkyl halides in a DMAc-H2O mixture con-taining K2CO3. A bifunctional catalytic mechanism is proposed for the chemical modification of the polyesters. © 1995 John Wiley & Sons, Inc.  相似文献   

8.
New dianhydrides containing t‐butyl and phenyl pendant groups have been synthesized and used as monomers, together with commercial diamines, to prepare novel polyimides. The influence of the chemical structure of the monomers on their reactivity has been studied by quantum semiempirical methods. The polyimides have been characterized by FTIR and by NMR in the case of soluble polymers. The presence of pendant groups and the method used to imidize polyimide precursors greatly affected polymer properties such as solubility, glass transition temperature, thermal stability, and mechanical properties. As a rule, the novel polyimides showed better solubility in organic solvents than the parent polyimides. Glass transition temperatures in the range 250–270°C and decomposition temperatures over 520°C were observed for the set of current polymers. Tensile strengths up to 135 MPa and mechanical moduli up to 3.0 GPa were measured on films of the current polyimides. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 805–814, 1999  相似文献   

9.
Two series of polyimides based on laterally attached p‐terphenyl and biphenyl groups were synthesized. The solubility and thermal properties were studied using DSC, thermogravimetric analysis, and the solubility test. These polymers exhibited good thermal stability and excellent solubility. The high solubility for both polymer series was attributed to the non‐coplanarity of diamine monomers and the use of fluorinated dianhydride, whereas the slightly better solubility for polymers based on p‐terphenyl was attributed to further weakening of interchain interaction of the polymers. Both polymer series exhibited glass‐transition temperatures (Tg's) in the range of 244–272 °C. The Tg's of polymers containing laterally attached p‐terphenyls were higher than those of their counterparts containing biphenyls by 5–17 °C. This was attributed to the formation of an interdigitated structure that hinders the segmental movement of polymer chains. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 2998–3007, 2001  相似文献   

10.
Summary: Four constitutionally isomeric copoly(amide acid)s (coPAAs), two alternating and two random, have been successfully obtained from the same combination of one non‐symmetrical alicyclic tetracarboxylic dianhydride (1.0 molar equivalents) and two symmetric aromatic diamines (0.5 molar equivalents each) by only slightly changing the reaction procedures. When the reaction mixture is subjected to chemical imidization conditions without isolation of coPAAs, the corresponding copolyimides (coPIs) are obtained in one pot. All of the coPIs are slightly yellow amorphous powders and the solubility of them is similar to each other. The glass transition temperatures of the alternating coPIs are lower in comparison to those of the random coPIs.

Schematic of the possible arrangement of monomers in the copoly(amide acid)s/copolyimides synthesized here.  相似文献   


11.
A series of novel polyimide electrolytes having long pendant sulfo‐ or phosphoalkoxy groups were synthesized for fuel‐cell applications. Sulfodecyloxy‐, phosphodecyloxy‐, and sulfophenoxydodecyloxy‐substituted benzidine monomers were synthesized from dihydroxybenzidine. These monomers were copolymerized with naphthalene tetracarboxylic dianhydride and fluorenylidene dianiline to give the corresponding polyimides. A flexible, ductile, and self‐standing membrane was obtained via casting from the polyimide solution. Because the acid groups were on long pendant side chains and away from the main chains, the polyimide membrane showed improved oxidative and hydrolytic stability in comparison with the polyimides with sulfonic acid groups on the main chains or on the short side chains. High thermal stability (no glass‐transition temperature and a decomposition temperature > 200 °C) was also obtained. The polyimide membrane displayed high proton conductivity of 10?1 S cm?1 at 120 °C. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3995–4005, 2006  相似文献   

12.
Hyperbranched polyimides (HBPI)s with high glass‐transition temperatures and excellent thermal stability were synthesized through the reaction of commercially available carboxylic acid dianhydrides with tris[4‐(4‐aminophenoxy)phenyl]ethane (TAPE). In particular, hyperbranched polyimide HBPI(TAPE‐DSDA), prepared through the reaction of TAPE with 3,3′,4,4′‐diphenylsulfonetetracarboxylic dianhydride (DSDA), showed higher thermal stability and good solubility. Furthermore, alkaline‐developable, photosensitive HBPI(TAPE‐DSDA)‐MA‐CA was prepared through the reaction of HBPI(TAPE‐DSDA) with glycidyl methacrylate with tetrabutylammonium bromide as a catalyst in N‐methyl‐2‐pyrrolidinone (NMP) followed by the addition reaction of cis‐1,2,3,6‐tetrahydrophthalic anhydride with triphenylphosphine as a catalyst in NMP. The glass‐transition temperatures of HBPI(TAPE‐DSDA)‐MA‐CA were greater than 300 °C. A resist composed of 74 wt % HBPI(TAPE‐DSDA)‐MA‐CA, 22.2 wt % trimethylpropane triacrylate, and 3.8 wt % Irgacure 907 as a photoinitiator achieved a resolution of a 55‐μm line pattern and a 275‐μm space pattern by UV irradiation (1000 mJ/cm2). © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 3697–3707, 2004  相似文献   

13.
A series of new soluble aromatic polyimides with inherent viscosities of 0.65–1.12 dL/g were synthesized from 1,3-bis(4-aminophenyl)-4,5-diphenylimidazolin-2-one and various aromatic tetracarboxylic dianhydrides by the conventional two-step procedure that included ring-opening polyaddition and subsequent thermal cyclodehydration. These polyimides could also be prepared by the one-pot procedure in homogeneous m-cresol solution. Most of the tetraphenyl-pendant polyimides were soluble in organic solvents such as N,N-dimethylacetamide, 1,3-dimethyl-2-imidazolidone, and m-cresol. Some polyimides gave transparent, flexible, and tough films with good tensile properties. The glass transition temperatures and 10% weight loss temperatures under nitrogen of the polyimides were in the range of 287–326 and 520–580°C, respectively. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1767–1772, 1998  相似文献   

14.
A new fluorinated diamine monomer, 2′,5′‐bis(4‐amino‐2‐trifluoromethylphenoxy)‐p‐terphenyl, was synthesized from the chloro‐displacement of 2‐chloro‐5‐nitrobenzotrifluoride with the potassium phenolate of 2,5‐diphenylhydroquinone, followed by hydrazine palladium‐catalyzed reduction. A series of trifluoromethyl‐substituted polyimides containing flexible ether linkages and laterally attached side rods were synthesized from the diamine with various aromatic dianhydrides via a conventional two‐step process. The inherent viscosities of the poly(amic acid) precursors were 0.84–1.26 dL/g. All the polyimides afforded flexible and tough films. The use of 4,4′‐oxydiphthalic anhydride and 2,2′‐bis(3,4‐dicarboxyphenyl)hexafluoropropane dianhydride produced essentially colorless polyimide films. Most of the polyimides revealed an excellent solubility in many organic solvents. The glass‐transition temperatures of these polyimides were recorded between 254 and 299 °C by differential scanning calorimetry, and the softening temperatures of the polymer films stayed in the range of 253–300 °C according to thermomechanical analysis. The polyimides did not show significant decomposition before 500 °C in air or under nitrogen. These polyimides also showed low dielectric constants (2.83–3.34 at 1 MHz) and low moisture absorption (0.4–2.2%). For a comparative study, a series of analogous polyimides based on the nonfluorinated diamine 2′,5′‐bis(4‐aminophenoxy)‐p‐terphenyl were also prepared and characterized. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 1255–1271, 2004  相似文献   

15.
New phenolic hydroxyl‐pendant aromatic polyimides were synthesized with the N‐silylated diamine method in two steps: the ring‐opening polyaddition of tetrakis(trimethylsilyl)‐substituted 4,4′‐diamino‐3,3′‐dihydroxybiphenyl to various aromatic tetracarboxylic dianhydrides, giving trimethylsiloxy‐pendant poly(amic acid) trimethylsilyl esters, and thermal imidization. The hydroxyl‐bearing polyimides were amorphous but insoluble in organic solvents. They had glass‐transition temperatures greater than 370 °C and temperatures of 10% weight loss greater than 415 °C in nitrogen. The hydroxyl‐pendant polypyromellitimide film had a high tensile strength and a high modulus of 310 MPa and 10 GPa, respectively. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 1790–1795, 2002  相似文献   

16.
A positive‐type photosensitive polyimide (PSPI) based on poly(amic acid) (PAA), a crosslinker 1,1,1‐tris{4‐[2‐(vinyloxy)ethoxy]phenyl}ethane (TVPE), a photoacid generator (PAG) (5‐propylsulfonyloxyimino‐5H‐thiophen‐2‐ylidene)‐2‐(methylphenyl)acetonitrile (PTMA), and a thermobase generator (TBG) t‐butyl 2,6‐dimethylpiperidine‐1‐carboxylate (BDPC) has been developed as a promising material in microelectronics. The PAA was prepared from 3,3′,4,4′‐biphenyltetracarboxylic dianhydride (BPDA) and 4,4′‐oxydianiline (ODA) in dimethyl sulfoxide (DMSO). The PSPI, consisting of PAA (69 wt %), TPVE (21 wt %), PTMA (3 wt %), and BDPC (7 wt %), showed high sensitivity of 21 mJ/cm2 and a high contrast of 6.8 when it was exposed to a 436‐nm line (g‐line), postbaked at 90 °C for 5 min, and developed with 1.69 wt % TMAHaq. A clear positive image of 8 μm line and space pattern was printed on film, which was exposed to 50 mJ/cm2 of g‐line by a contact printing mode and fully converted to the corresponding polyimide (PI) pattern on heating at 200 °C, confirmed by FTIR spectroscopy. Thus, this system will be a good candidate for next generation PSPIs. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 3362–3369, 2009  相似文献   

17.
A novel positive‐working and aqueous‐base‐developable photosensitive poly(imide benzoxazole) precursor based on a poly(amic acid hydroxyamide) bearing phenolic hydroxyl groups and carboxylic acid groups, a diazonaphthoquinone (DNQ) photosensitive compound, and a solvent was developed. Poly(amic acid hydroxyamide) was prepared through the polymerization of 2,2‐bis(3‐amino‐4‐hydroxyphenyl)hexafluoropropane, trimellitic anhydride chloride, and 4,4′‐oxydibenzoyl chloride. Subsequently, the thermal cyclization of the poly(amic acid hydroxyamide) precursor at 350 °C produced the corresponding poly(imide benzoxazole). The inherent viscosity of the precursor polymer was 0.17 dL/g. The cyclized poly(imide benzoxazole) showed a high glass‐transition temperature of 372 °C and 5% weight loss temperatures of 535 °C in nitrogen and 509 °C in air. The structures of the precursor polymer and the fully cyclized polymer were characterized with Fourier transform infrared and 1H NMR. The photosensitive polyimide precursor containing 25 wt % DNQ photoactive compound showed a sensitivity of 256 mJ/cm2 and a contrast of 1.14 in a 3‐μm film with a 0.6 wt % tetramethylammonium hydroxide developer. A pattern with a resolution of 5 μm was obtained from this composition. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 5990–5998, 2004  相似文献   

18.
A new cardo diimide‐dicarboxylic acid, 1,1‐bis[4‐(4‐trimellitimidophenoxy)phenyl]cyclododecane (BTPCD), containing a pendant cyclododecyl group was synthesized by the condensation reaction of 1,1‐bis[4‐(4‐aminophenoxy)phenyl]cyclododecane with trimellitic anhydride in glacial acetic acid. A series of new cardo polyamide‐imides were prepared by the direct polycondensation of BTPCD and various aromatic diamines in N‐methyl‐2‐pyrrolidinone (NMP) with triphenyl phosphite and pyridine as condensing agents. The polymers were produced in high yields and with moderate‐to‐high inherent viscosities of 0.72–1.02 dL g−1. The number‐average and weight‐average molecular weights of the polymers ranged from 21,000 to 49,000 and 58,000 to 92,000, respectively. All the polymers exhibited excellent solubility and could be readily dissolved in various solvents such as NMP, N,N‐dimethylacetamide, N,N‐dimethylformamide, dimethyl sulfoxide, pyridine, cyclohexanone, and tetrahydrofuran. These polyamide‐imides had glass‐transition temperatures between 241 and 262 °C and 10% weight‐loss temperatures ranging from 469 to 511 °C in nitrogen. The polymer films had a tensile strength range of 79–108 MPa, an elongation at break range of 7–14%, and a tensile modulus range of 2.0–2.4 GPa. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 2787–2793, 2000  相似文献   

19.
20.
A series of hyperbranched polyimides (HBPIs) were synthesized by reacting a triamine monomer N ,N ′,N ″‐tris(4‐methoxyphenyl)‐N ,N ′,N ″‐tris(4‐phenylamino)?1,3,5‐benzenetriamine with various dianhydrides such as oxydiphthalic dianhydride (ODPA), 3,3′,4,4′‐diphenylsulfonetetracarboxylic dianhydride (DSDA), 3,3′,4,4′‐benzophenonetetracarboxylic dianhydride (BTDA), and pyromellitic dianhydride (PMDA). The hyperbranched polyimide (6FHBPI) using 4,4′‐(hexafluoroisopropylidene)diphthalic anhydride (6FDA) as dianhydride monomer was also added into the discussion. All the hyperbranched polyimides exhibited excellent organo‐solubility and high thermal stability. Memory devices with a sandwiched structure of indium tin oxide (ITO)/HBPI/Al were constructed by using these HBPIs as the active layers. All these HBPIs based memory devices exhibited favorable memory performances, with switching voltages between ?1.3 V and ?2.5 V, ON/OFF current ratios up to 107 and retention times long to 104 s. Tunable memory characteristics from electrical insulator to volatile memory, and then to nonvolatile memory were obtained by adjusting the electron acceptors of these HBPIs. Molecular simulation results suggested that the electron affinity and the dipole moment of these HBPIs were responsible for the conversion of the memory characteristics. With the electron affinity and dipole moment of these HBPIs increasing, the memory characteristics turned from volatile to nonvolatile. The present study suggested that tunable memory performance could be achieved through adjusting the acceptor moieties of the hyperbranched polyimides. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55 , 2281–2288  相似文献   

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