Novel soluble fluorinated poly(ether imide)s with different pendant groups: Synthesis,thermal, dielectric,and optical properties

Three types of new bis(ether dianhydride) monomers, [4,4′‐(2‐(3′‐methylphenyl)‐1,4‐phenylenedioxy)‐diphthalic anhydride (4a)], [4,4′‐(2‐(3′‐trifluoromethylphenyl)‐1,4‐phenylenedioxy)‐diphthalic anhydride (4b)], and [4,4′‐(2‐(3′,5′‐ditrifluoromethylphenyl)‐1,4‐phenylenedioxy)‐diphthalic anhydride (4c)] were prepared via a multistep reaction sequence. Three series of soluble poly(ether imide)s (PEIs) were prepared from the obtained dianhydrides by a two‐step chemical imidization method. Experimental results indicated that all the PEIs had glass transition temperature in the range of 200–230 °C and the temperature of 5% weight loss in the range of 520–590 °C under nitrogen. The PEIs showed excellent solubility in a variety of organic solvents due to introduction of the bulky pendant groups and were capable of forming tough films. The casting films of PEIs (80–91 μm in thickness) had tensile strengths in the range from 88 to 117 MPa, tensile modulus from 2.14 to 2.47 GPa, and elongation at break from 15 to 27%. The casting films showed UV‐Vis absorption edges at 357–377 nm, low dielectric constants of 2.73–2.82, and water uptakes lower than 0.66 wt %. The spin‐coated films of PEIs presented a minimum birefringence value as low as 0.0122 at 650 nm and low optical absorption at the optical communication wavelengths of 1310 and 1550 nm. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3281–3289, 2010     

Synthesis and properties of novel regioirregular polyimides from easily synthesized asymmetrical dichlorophthalimide monomers

New asymmetrical aromatic dichlorophthalimide monomers containing pendant groups (trifluoromethyl or methyl) were conveniently prepared from inexpensive and commercially available compounds. With these monomers, a new class of soluble polyimides with a regioirregular structure within the polymer backbone was obtained by the Ni(0)‐catalyzed polymerization method. The structures of the polymers were confirmed by various spectroscopic techniques. The polyimides displayed better solubility and higher thermal stability than the corresponding regular polyimides. In addition, fluorinated polyimides in this study had low dielectric constants ranging from 2.52 to 2.78, low moisture absorptions of less than 0.59%, and low thermal expansion coefficients between 10.6 and 19.7 ppm/°C. The oxygen permeability coefficients and permeability selectivity of oxygen to nitrogen of the films were in the ranges of 2.99–4.20 barrer and 5.55–7.50, respectively. We have demonstrated that the synthetic pathway for polyimides provides a successful approach to increasing the solubility and processability of polyimides without sacrificing their thermal stability. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3550–3561, 2007     

Synthesis of nonlinear optical polyimides containing azodiamine derivative chromophores and their electrooptic and thermal properties

Some thermally stable second‐order nonlinear optical (NLO) polyimides were synthesized. The polyimides were prepared by the ring‐opening polyaddition of 4,4′‐(hexafluoroisopropylidene) diphthalic anhydride and pyromellitic dianhydride with two aromatic azodiamine derivatives as the NLO chromophores. These chromophores, based on a nitro group connected with azobenzene as the acceptor end of a donor–π‐bridge–acceptor chromophore and a diamine group as the donor end, had specific chemical stability. On the basis of ZERNER'S INDO methods, according to the sum‐over‐states formula, a program for the calculation of nonlinear second‐order optical susceptibilities was devised. The resulting polyimides had high number‐average and weight‐average molecular weights of up to 26,000 and 53,500, respectively, and a large glass‐transition temperature of 248 °C. With an in situ poling and temperature ramping technique, the optimal temperatures (T_opt's) for corona poling were obtained for the largest second‐order NLO response. The electrooptic coefficient (γ₃₃) of a polyimide at a wavelength of 830 nm was up to 21 pm/V after corona poling under its T_opt, and the value remained at elevated temperatures (>90.6% was retained at 240 °C for >120 h). The thermal stability of the NLO polyimides was studied with UV spectrometry after poling of the films. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2478–2486, 2002     

Synthesis and memory characteristics of highly organo‐soluble hyperbranched polyimides with various electron acceptors

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     

Synthesis and properties of hyperbranched polyimides derived from novel triamine with prolonged chain segments

Novel pyridine‐containing hyperbranched polyimides (HBPIs) were synthesized by using a new triamine 2,4,6‐tris[3‐(4‐aminophenoxy)phenyl]pyridine with prolonged chain segments, ether linkage and meta‐linked units as a BB′₂‐like monomer, various commercial aromatic dianhydrides as A₂ monomers. Most of the obtained HBPIs were readily soluble in common organic solvents such as N,N‐dimethylformamide, N,N‐dimethylacetamide, N‐methyl‐2‐pyrrolidone, m‐Cresol, and so forth. Meanwhile, they also had good thermal stability with the glass transition temperatures (T_gs) all above 210 °C, the temperature at 10% weight loss of 537.1–574.4 °C in nitrogen atmosphere. Strong and flexible HBPI films were obtained, which had good mechanical properties with tensile strengths of 83.3–95.8 MPa, tensile modulus of 1.82–2.43 GPa and elongations at break of 4.84–6.98%. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2425–2437     

Tunable memory performances of the porphyrin terminated hyperbranched polyimides

Herein, a functional hyperbranched polyimide, denoted as ATPP‐HBPI, was synthesized by termination of polyamic acid with 5‐(4‐aminophenyl)‐10, 15, 20‐triphenylporphyrin (ATPP) and chemical imidization. Subsequently, ATPP‐HBPI was coordinated with Zn ion to give Zn‐ATPP‐HBPI. In the HBPIs, the porphyrin terminals acted as the electron donor (D) and the 6FDA moieties acted as the electron acceptor (A) to promote the electron transition. Both ATPP‐HBPI and Zn‐ATPP‐HBPI exhibited good organo‐solubility and high thermal stability. They were used as the electroactive layer to fabricate the memory device with a configuration of indium tin oxide (ITO)/HBPI/Al to evaluate their bistability. The devices exhibited different memory behaviors, WORM for ATPP‐HBPI and SRAM for Zn‐ATPP‐HBPI, respectively. Optical and electrochemical experiments and molecular simulation were carried out to illustrate this phenomenon of performance transformation. The results show that the metallization of terminal of the HBPIs provides a strategy for tailoring the memory characteristics of the devices. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56, 1953–1961     

Atomistic models of three fluorinated polyimides in the amorphous state

Molecular models of three fluorinated polyimides based on the 4,4′‐(hexafluoroisopropylidene)diphthalic dianhydride (6FDA) have been studied using molecular dynamics (MD) simulations. The respective diamines were 4,4′‐hexafluoroisopropylidene dianiline (6FpDA), 3,3′‐hexafluoroisopropylidene dianiline (6FmDA), and 2,4,6‐trimethyl‐1,3phenylenediamine (DAM). Thirty independent samples were prepared using a hybrid pivot Monte Carlo‐MD generation technique and average densities were found to be in very good agreement with experiment. Model structures also agreed with available wide‐angle X‐ray scattering data. Cohesive energies, Hildebrand solubility parameters, fractional free volumes (FFV), void space distributions and intermolecular as well as intramolecular interactions were analyzed. The differences in bulk properties between both 6FDA‐6FpDA and 6FDA‐6FmDA isomers remain fairly small, although the configurations of the former are more extended. 6FDA‐DAM has a lower density, larger intermolecular distances, and higher free volume than the other two polyimides. Results are discussed with respect to their use as matrices for gas separation. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 1166–1180, 2009     

Synthesis and characterization of hyperbranched polyimides with good organosolubility and thermal properties based on a new triamine and conventional dianhydrides

A triamine monomer, 1,3,5‐tris(4‐aminophenoxy)benzene (TAPOB), was synthesized from phloroglucinol and 4‐chloronitrobenzene, and it was successfully polymerized into soluble hyperbranched polyimides (HB PIs) with commercially available dianhydrides: 4,4′‐(hexafluoroisopropylidene)diphthalic anhydride (6FDA), 4,4′‐oxydiphthalic anhydride (ODPA), and 3,3′,4,4′‐benzophenonetetracarboxylic dianhydride (BTDA). Different monomer addition methods and different monomer molar ratios resulted in HB PIs with amino or anhydride end groups. From ¹H NMR spectra, the degrees of branching of the amino‐terminated polymers were estimated to be 0.65, 0.62, and 0.67 for 6FDA–TAPOB, ODPA–TAPOB, and BTDA–TAPOB, respectively. All polymers showed good thermal properties with 10% weight‐loss temperatures (T₁₀'s) above 505 °C and glass‐transition temperatures (T_g's) of 208–282 °C for various dianhydrides. The anhydride‐terminated HB PIs showed lower T₁₀ and T_g values than their amino‐terminated counterparts. The chemical conversion of the terminal amino or anhydride groups of the 6FDA‐based polyimides into an aromatic imido structure improved their thermal stability, decreased their T_g, and improved their solubility. The HB PIs had moderate molecular weights with broad distributions. The 6FDA‐based HB PIs exhibited good solubility even in common low‐boiling‐point solvents such as chloroform, tetrahydrofuran, and acetone. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 3804–3814, 2002     

Facile synthesis of hyperbranched polyimides from A2 + BB′2 monomers

Facile syntheses of hyperbranched polyimides were realized by the polymerization of A₂ + BB^′₂ monomers, 2,2‐bis(3,4‐dicarboxylphenyl) hexafluoropropane dianhydride (6FDA) + 2,4,6‐triaminopyrimidine (TAP), performed by mixing the monomers together in N‐methylpyrrolidone at 17% w/v concentrations with molar ratios of 6FDA:TAP ranging from 1:1 to 2:1. The lower reactivity of 2‐amino as compared with 4‐/6‐amino in TAP, demonstrated by ¹H NMR, was probably the main reason for no gelation formed during the polymerization although monomer conversions surpassed the theoretical gel points. Fourier transform infrared spectroscopy and NMR were used to verify the structures of the obtained polymers. ¹H NMR analysis indicated the degrees of branching (DB) of the polymers increased from 36 to 83% with the molar ratios of 6FDA:TAP increasing from 1:1 to 2:1. Molecular weights were determined by gel permeation chromatography, and inherent viscosities were measured. Glass‐transition temperature values, determined by differential scanning calorimetry, decreased when DB increased, and thermogravimetric analysis reflected the excellent thermal stability of the obtained hyperbranched polyimides. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 4563–4569, 2002     

Synthesis and properties of nonlinear optical side chain soluble polyimides for photonics applications

Aromatic polyimides with side chain nonlinear optical chromophores have been investigated through a facile two-step synthetic route. First, various poly(hydroxy imide)s have been synthesized by direct thermal imidization of diaminophenol dihydrochloride salt and aromatic dianhydride monomers. The resulting polyimides bearing phenolic hydroxy groups were found to react easily with the terminal hydroxy group on the chromophores via the Mitsunobu condensation to give corresponding polyimides with high optical nonlinearities and good solubility in common organic solvents. Detailed physical properties showed that these polyimides have a molecular weight (M_w) of 31,000 and high glass transition temperature above 220°C, ensuring a long-term alignment stability at elevated temperature. The electrooptic coefficients, r₃₃, of the electrically poled polymer films were in the range 1.8–7.6 pm/V at 1.3 μm. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 301–307, 1998     

Synthesis and characterization of highly transparent and hydrophobic fluorinated polyimides derived from perfluorodecylthio substituted diamine monomers

Two new perfluorodecylthio substituted aromatic diamines, namely 2,4‐diamino‐1‐(1H,1H,2H,2H‐perfluorodecathio)benzene (DAPFB) and 2,2'‐Bis((1H,1H,2H,2H‐perfluorodecyl)thio)[1,1'‐biphenyl]4,4'‐diamine (BPFBD) were synthesized and polycondensed with 4,4′‐(hexafluoroisopropylidene)diphthalic anhydride (6FDA) to produce two new perfluorinated polyimides (PI2 and PI4). The chemical structures of these polyimides were confirmed by Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopy and elemental analysis. Two other polyimides (PI1 and PI3) were also synthesized from 6FDA and analogous perfluorodecylthio unsubstituted diamines to investigate the incorporation effect of perfluorodecylthio group on various physical and chemical properties of the synthesized PIs. Compared with PI1 and PI3, PI2 and PI4 exhibited improved solubility, optical transparency, and hydrophobicity, lower moisture absorption, dielectric constant, and thermo‐mechanical stabilities owing to the presence of the perfluorodecylthio side group in the polymer chain. Even though thermo‐mechanical properties of PI2 and PI4 ( : 413 and 404 °C, T_g: 220 and 209 °C, tensile strength of 101 and 76 MPa, tensile modulus of 1.7 and 1.5 GPa and elongation at break of 8 and 10%, respectively) were reduced in comparison to PI1 and PI3 but still were good enough for most of the practical applications. Most importantly, the presence of the perfluorodecylthio side group in BPFBD considerably reduced the dielectric constant of PI4 to 2.71 which was quite low as aromatic polyimide. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 479–488     

Synthesis and properties of cross‐linkable high molecular weight fluorinated copolyimides

A series of novel high molecular weight fluorinated co‐polyimides (Co‐PIs) containing styryl side chain based on 1,3‐bis(2‐trifluoromethyl‐4‐aminophenoxy)‐5‐(2,3,4,5‐tetrafluorophenoxy)benzene (6FTFPB) were successfully synthesized. The weight‐average molecular weights (M_ws) and polydispersities of the co‐polyimides were in the range 8.93–10.81 × 10⁴ and 1.33–1.82, respectively. The co‐polyimide film showed excellent solubility in organic solvents, high tensile properties (tensile strength exceeded 91 MPa), excellent optical transparency (cutoff wavelength at 332–339 nm and light transparencies above 89% at a wavelength of 550 nm), and high thermal stability (5% thermal weight‐loss temperature up to 510 °C). The casting and spinning films could be cross‐linked by thermal curing. The cured films show better combination property (including excellent resistance to solvents) than that of co‐polyimides. For instance, the glass transition temperature of Co‐PI‐1 (the molar weight ratio of 6FTFPB was 30%) increased from 217 to 271 °C, the tensile strength enhanced from 94 to 96 MPa, the 5% thermal weight‐loss temperature improved from 514 to 525 °C. Moreover, after cured, Co‐PI‐1 film also has a coefficient of thermal expansion (CTE) value of 60.3 ppm °C^?1, low root mean square surface roughness (R_q) at 4.130 nm and low dielectric constant of 2.60. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 349–359     

Synthesis and characterization of organosoluble ditrifluoromethylated aromatic polyimides

Two novel diamine monomers, 1,4‐bis (4‐aminophenoxy)‐2‐[(3′,5′‐ditrifluoromethyl)phenyl]benzene and 1,4‐bis [2′‐cyano‐3′(4″‐amino phenoxy)phenoxy]‐2‐[(3′,5′‐ditrifluoromethyl)phenyl] benzene, were synthesized from (3,5‐ditrifluoromethyl)phenylhydroquinone. A series of ditrifluoromethylated aromatic polyimides derived from the diamines were prepared through a typical two‐step polymerization method. These polyimides had a high thermal stability, and the temperatures at 10% weight loss were above 507 °C in nitrogen. Most of the polymers showed good solubility in anhydrated 1‐methyl‐2‐pyrrolidone, N,N‐dimethylacetamide, N,N‐dimethylformamide, chloroform, and tetrahydrofuran at room temperature. All the polymers formed transparent, strong, and flexible films with tensile strengths of 63.6–95.8 MPa, elongations at break of 5–10%, and Young's moduli of 2.38–2.96 GPa. The dielectric constants estimated from the average refractive indices are 2.69–2.89. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3018–3029, 2005     

Synthesis and gas transport properties of ODPA-TAP-ODA hyperbranched polyimides with various comonomer ratios

A series of hyperbranched copolyimides (HBPI)s based on commercially available monomers 4,4′-oxydiphthalic anhydride (ODPA), 2,4,6-triaminopyrimidine (TAP) and 4,4′-oxydianiline (ODA) were prepared. The synthesis involved the formation of hyperbranched polyamic acid (PAA) precursors in the first step and the thermal imidization of cast thin PAA films in the second step. Two basic types of HBPIs were prepared by controlling the molar ratio of ODPA and an amine mixture of TAP and ODA. When the molar ratio was 1:1, the amine-terminated HBPIs were obtained; with the molar ratio of 2:1 anhydride-terminated HBPIs were prepared. Degree of branching was estimated by ¹H and ¹³C NMR analysis. It was found that approximately 48% of TAP units presented in ODPA:TAP:ODA = 1:0.75:0.25 HBPI macromolecules create the branching unit. Amine-terminated HBPIs showed moderate weight-average molecular weights and these values rather higher than for the anhydride-terminated HBPIs. With increasing ODA comonomer content in amine-terminated HBPIs increased their molecular weight and thermal and mechanical stability, whereas in anhydride-terminated HBPIs these trends were opposite. Amine-terminated HBPIs generally exhibited higher thermal stability than the anhydride-terminated ones. Gas permeability coefficients of both HBPIs types increased with increasing content of ODA comonomer. Prepared membranes exhibited high separation performance and have a potential to be utilized in industrial gas separation applications.     

Synthesis and characterization of soluble polyimides functionalized with carbazole moieties

Here, we report the synthesis and characterization of new soluble polyimides that are functionalized using carbazole moieties in their side chain. As a monomer for synthesizing the polyimides, 4″‐carbazole‐9‐yl‐[1,1′;2′,1″] terphenyl‐4‐4′‐diamine and 2‐(3‐carbazol‐9‐yl‐propyl)‐biphenyl‐4,4′‐diamine were synthesized and then characterized using ¹H NMR, ¹³C NMR, FTIR, UV–visible and photoluminescence spectroscopy, differential scanning calorimetry (DSC), and elemental analysis. The polyimides synthesized via chemical imidization processes were characterized with X‐ray photoelectron spectroscopy, gel permeation chromatography, wide angle X‐ray diffraction, thermogravimetric analysis, DSC, tensile strength measurement, and dielectric property measurement. Results showed that the synthesized polyimides were soluble in a variety of organic solvents, optically transparent in a visible range, thermally stable, mechanically strong, and considerably low dielectric. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 8117–8130, 2008     

Synthesis and characterization of some novel aromatic polyimides

Three new diamines 1,2-di(p-aminophenyloxy)ethylene, 2-(4-aminophenoxy)methyl-5-aminobenzimidazole and 4,4-(aminopheyloxy) phenyl-4-aminobenzamide were synthesized and polymerized with 3,3′,4,4′-benzophenone tetracarboxylic acid dianhydride (BP), 4,4′-(hexafluoroisopropyledene)diphthalic anhydride (HF) and 3,4,9,10-perylene tetracarboxylic acid dianhydride (PD) either by one step solution polymerization reaction or by two step procedure. The later includes ring opening poly-addition to give poly(amic acid), followed by cyclodehydration to polyimides with the inherent viscosities 0.62-0.97 dl/g. Majority of polymers are found to be soluble in most of the organic solvents such as DMSO, DMF, DMAc, m-cresol even at room temperature and few becomes soluble on heating. The degradation temperature of the resultant polymers falls in the ranges from 240 °C to 550 °C in nitrogen (with only 10% weight loss). Specific heat capacity at 300 °C ranges from 1.1899 to 5.2541 J g⁻¹ k⁻¹. The maximum degradation temperature ranges from 250 to 620 °C. T_g values of the polyimides ranged from 168 to 254 °C.     

Synthesis and photochemical properties of novel pentamethylated norbornadiene containing polyimides

A novel pentamethylated norbornadiene (NBD) based dianhydride, α,α′‐bis‐(3,4,5,6,7‐pentamethylcyclopenta‐2,4‐dienyl)meta‐xylene‐1,2‐dianhydride (3), was prepared from α,α′‐bis‐(pentamethylcyclopentadienyl)meta‐xylene (1) and acetylene dicarboxylic acid. The bis‐adduct formed via Diels–Alder reaction afforded tetra‐acid (2), which was chemically cyclodehydrated to lead the targeted dianhydride (3). New polyimides containing NBD moieties in the main chain were prepared from the dianhydride monomer (3) and various aromatic diamines. The chemical structure of the polymers was confirmed by both ¹H and ¹³C NMR analysis. Their Molecular weights were also measured by SEC. All of these polyimides are soluble at room temperature in common organic solvents, such as chloroform, dichloromethane, THF, DMSO, DMF, and NMP, and show good thermal stabilities. The photochemical isomerization of the NBD into quadricyclane (QC) was investigated by UV/vis spectrophotometry from polymer films using visible sunlight as irradiation source. It was found that the kinetic rate of the conversion NBD‐QC which proceeded smoothly is a first kinetic order. The stored energies released by the transformation of QC groups into NBD ones of the irradiated polymer films were also evaluated by DSC measurement and were found to be around 90 kJ mol^?1. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011     

Synthesis and characterization of negative‐type photosensitive hyperbranched polyimides with excellent organosolubility from an A2 + B3 monomer system

A series of photosensitive hyperbranched polyimides (HB‐PIs) were prepared through facile end‐group modifications of the fully imidized polymer. A triamine, 1,3,5‐tris(4‐aminophenoxy)benzene, and a dianhydride, 4,4′‐(hexafluoroisopropylidene)diphthalic anhydride, were condensed with a dropwise addition method in a molar ratio of 1/2 to afford an anhydride‐terminated poly(amic acid) precursor, which was then end‐capped by 4‐aminophenol and chemically imidized to yield a phenol‐terminated HB‐PI. The modifications of the terminal phenol groups of the polyimide by acyl chloride compounds (acryloyl chloride, methylacryloyl chloride, and cinnamoyl chloride) gave the target polymers. The photosensitive HB‐PIs showed good thermal properties and excellent solubility even in low‐boiling‐point solvents at room temperature, such as acetone, 1,1,2‐trichloroethane, tetrahydrofuran, and chloroform. Photosensitive property studies revealed good photolithographic properties with a resolution greater than 3 μm and a sensitivity of 650–680 mJ/cm². © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 1735–1744, 2004