Synthesis and nonlinear optical properties of novel Y‐type polyurethane containing tricyanovinylthiazole with enhanced thermal stability of second harmonic generation

A novel Y‐type poly[iminocarbonyloxyethyl‐5‐methyl‐4‐{2‐thiazolylazo‐4‐(1,2,2‐tricyanovinyl)}resorcinoxyethyloxycarbonylimino‐(3,3′‐dimethoxy‐4,4′‐biphenylene)] 4 containing 5‐methyl‐4‐{5‐(1,2,2‐tricyanovinyl)‐2‐thiazolylazo}resorcinoxy groups as nonlinear optical (NLO) chromophores, which constitute part of the polymer backbone, was prepared and characterized. Polyurethane 4 is soluble in common organic solvents such as acetone and N,N‐dimethylformamide. It showed a thermal stability up to 250 °C in thermogravimetric analysis thermogram and the glass‐transition temperature (T_g) obtained from differential scanning calorimetry thermogram was around 118 °C. The second harmonic generation coefficient (d₃₃) of poled polymer films at 1560 nm fundamental wavelength was around 8.43 × 10^?9 esu. The dipole alignment exhibited a thermal stability even at 12 °C higher than T_g, and there was no SHG decay below 130 °C due to the partial main‐chain character of the polymer structure, which is acceptable for NLO device applications. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1166–1172, 2010     

Molecular design,synthesis, and properties of Y‐type nonlinear optical polyester containing tricyanovinylthiophene with enhanced thermal stability of second harmonic generation

1‐{3,4‐Di‐(2‐hydroxyethoxy)phenyl}‐2‐(2‐thiophenyl)ethene (5) was prepared and condensed with terephthaloyl chloride to yield polyester (6). Polymer 6 was reacted with tetracyanoethylene to give a new Y‐type polyester (7) containing 1‐(3,4‐dioxyethoxy)phenyl‐2‐{5‐(2,2,3‐tricyanovinyl)‐2‐thiophenyl)}ethenyl groups as NLO‐chromophores, which are components of the polymer backbones. Polyester 7 is soluble in common organic solvents such as N,N‐dimethylformamide and acetone. Polymer 7 showed a thermal stability up to 300 °C in thermogravimetric analysis with glass transition temperature (T_g) obtained from differential scanning calorimetry near 126 °C. The second harmonic generation (SHG) coefficient (d₃₃) of poled polymer film at the 1560 nm fundamental wavelength was around 6.57 × 10^?9 esu. The dipole alignment exhibited high thermal stability up to the T_g, and there was no SHG decay below 125 °C due to the partial main‐chain character of polymer structure, which is acceptable for NLO device applications. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 1911–1919, 2009     

Synthesis and electro‐optic properties of novel X‐type polyurethane containing nitrophenylazonitroresorcinoxy group with highly enhanced thermal stability of dipole alignment

Novel X‐type polyurethane 4 containing 4‐(4‐nitrophenylazo)‐6‐nitroresorcinoxy groups as nonlinear optical (NLO) chromophores, which are parts of the polymer main chains, was prepared and characterized. Polyurethane 4 is soluble in common organic solvents such as acetone and N,N‐dimethylformamide. It shows thermal stabilities up to 270 °C from thermogravimetric analysis with glass transition temperature obtained from differential scanning calorimetry of about 134 °C. The second harmonic generation (SHG) coefficient (d₃₃) of poled polymer film at 1064 nm fundamental wavelength is 5.37 × 10^?9 esu. Polymer 4 exhibits a thermal stability up to T_g, and no significant SHG decay is observed below 135 °C, which is acceptable for NLO device applications. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 760–766     

Synthesis and properties of novel Y‐type nonlinear optical polyimides with high thermal stability of second harmonic generation

2,4‐Bis‐(3,4‐dicarboxyphenylcarboxyethoxy)‐1‐(2,2‐dicyanovinyl)benzene dianhydride (4) was prepared and reacted with 4,4′‐oxydianiline, 4,4′‐diaminobenzanilide and 4,4′‐(hexafluoroisopropylidene)dianiline to yield novel Y‐type polyimides 5‐7 containing 2,4‐dioxybenzylidenemalononitrile groups as nonlinear optical (NLO) chromophores, which constitute parts of the polymer backbone. The resulting polyimides 5‐7 are soluble in polar solvents such as dimethylsulfoxide and N,N‐dimethylformamide. Polymers 5‐7 showed a thermal stability up to 330 °C in thermogravimetric analysis thermograms with T_g values obtained from differential scanning calorimetry thermograms in the range 179–194 °C. The second harmonic generation (SHG) coefficients (d₃₃) of poled polymer films at the 1064 nm fundamental wavelength were around 5.56 × 10^?9 esu. The dipole alignment exhibited exceptionally high thermal stability even at 20 °C higher than the glass‐transition temperature there was no SHG decay below 215 °C because of the partial main‐chain character of polymer structure, which is acceptable for NLO device applications. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 3078–3087, 2008     

Synthesis and nonlinear optical properties of novel Y‐type polyester containing tricyanovinylthiazolylazoresorcinoxy group with enhanced thermal stability of dipole alignment

Novel Y‐type polyester 4 containing 5‐methyl‐4‐{5‐(1,2,2‐tricyanovinyl)‐2‐thiazolylazo}resorcinoxy groups as nonlinear optical (NLO) chromophores, which are parts of the polymer backbone, was prepared, and its NLO properties were investigated. Polyester 4 is soluble in common organic solvents such as N,N‐dimethylformamide and dimethylsulfoxide. Polymer 4 shows a thermal stability up to 250 °C from thermogravimetric analysis with glass‐transition temperature obtained from differential scanning calorimetry of approximately 94 °C. The second harmonic generation (SHG) coefficient (d₃₃) of poled polymer film at 1560‐nm fundamental wavelength is 8.12 × 10^?9 esu. The dipole alignment exhibits a thermal stability even at 6 °C higher than glass‐transition temperature (T_g), and no significant SHG decay is observed below 100 °C due to the partial main‐chain character of polymer structure, which is acceptable for NLO device applications. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011     

Molecular design,synthesis, and nonlinear optical properties of novel T‐type polyimides with exceptionally high thermal stability of the second harmonic generation

2,5‐Bis‐(3,4‐dicarboxyphenylcarboxyethoxy)‐4′‐nitrostilbene dianhydride was prepared and reacted with 1,4‐phenylenediamine, 4,4′‐oxydianiline, 4,4′‐diaminobenzanilide, and 4,4′‐(hexafluoroisopropylidene)dianiline to yield unprecedented novel T‐type polyimides ( 4 – 7 ) containing 2,5‐dioxynitrostilbenyl groups as nonlinear optical chromophores, which constituted parts of the polymer backbones. 4 – 7 were soluble in polar solvents such as acetone and N,N‐dimethylformamide. They showed thermal stability up to 300 °C in thermogravimetric analysis thermograms; the glass‐transition temperatures obtained from differential scanning calorimetry thermograms were around 153 °C. The second harmonic generation (SHG) coefficients (d₃₃) of poled polymer films at the 1064‐cm^?1 fundamental wavelength were around 4.35 × 10^?9 esu. The dipole alignment exhibited exceptionally high thermal stability even at 45 °C higher than the glass‐transition temperature, and there was no SHG decay below 200 °C because of the partial main‐chain character of the polymer structure, which was acceptable for nonlinear optical device applications. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 3189–3199, 2004     

NOTE: Synthesis and Characterization of a Poly(acrylamide) with Pendant 1,4-piperazine-2,5-dione Moieties via Post-polymerization Cyclization

A poly(acrylamide) was synthesized from N ^α -Boc-N ^? -acrolyl-l-lysylglycine methyl ester via radical polymerization. This polymer typically had Mn ～ 100,000 g/mol, Mw ～ 300,000 g/mol, and a T_g of 93°C. Removal of Boc with TFA and cyclization with DABCO? in DMSO at 65°C afforded a soluble piperazinedione-containing polymer that had a T_g of 157°C and thermal stability up to 300°C. These results demonstrate a viable and efficient synthetic route to piperazinedione-containing polyacrylamides of high molecular weight. Related polymers that incorporate substituted indane moieties could be useful high T_g materials for fabrication of LC and NLO devices.     

Synthesis of poly(2‐ethylhexyl acrylate)/clay nanocomposite by in situ living radical polymerization

This investigation reports the preparation of tailor‐made poly(2‐ethylhexyl acrylate) (PEHA) prepared via in situ living radical polymerization in the presence of layered silicates and characterization of this polymer/clay nanocomposite. Being a low T_g (?65 °C) material, PEHA has very good film formation property for which it is used in paints, adhesives, and coating applications. 2‐Ethylhexyl acrylate was polymerized at 90 °C using CuBr and Cu(0) as catalyst in combination with N,N,N′,N″,N″‐pentamethyl diethylenetriamine (PMDETA) as ligand. A tremendous enhancement in reaction rate and polymerization data was achieved when acetone was added as additive to increase the efficiency of the catalyst system. PEHA/clay nanocomposite was prepared at 90 °C using CuBr as catalyst in combination with PMDETA as ligand. Different types of clay with same loading were also used to study the effect on reaction rate. The molecular weight (M_n) and polydispersity index of the prepared nanocomposites were characterized by size exclusion chromatography. The active end group of the polymer chain was analyzed by ¹H NMR analysis and by chain extension experiment. Polymer/clay interaction was studied by Fourier Transform Infrared spectrometry and wide‐angle X‐ray diffraction analyses. Distribution of clay in the polymer matrix was studied by the transmission electron microscopy. Thermogravimetric analysis showed that thermal stability of PEHA/clay nanocomposite increases on addition of nanoclay. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011     

Controlled synthesis of new amphiphilic glycopolymers with liquid crystal grafts

A cholesterol‐based liquid crystal monomer, diethylene glycol cholesteryl ether acrylate (DEGCholA), has been successfully polymerized by atom transfer radical polymerization (ATRP) for the first time. Appropriate experimental conditions to control the polymerization of DEGCholA have been investigated using a model initiator (ethyl 2‐bromoisobutyrate) in tetrahydrofuran (THF) or toluene at 60 °C. Well‐controlled ATRP of DEGCholA was obtained using N,N,N′,N′,N″‐pentamethyldiethylenetriamine as ligand in THF at 60 °C. These conditions were then applied to initiate the ATRP of DEGCholA from multifunctional macroinitiators based on dextran. Using a protection/deprotection synthetic scheme, novel graft glycopolymers (Dex‐g‐PDEGCholA) have been synthesized. The mesomorphic properties of DEGCholA, PDEGCholA, and Dex‐g‐PDEGCholA have been studied by thermal polarizing optical microscopy, differential scanning calorimetry, and X‐ray scattering. PDEGCholA and Dex‐g‐PDEGCholA show an interdigitated smectic A phase (SmA_d) between T_g (～30 °C) and around 170 °C. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013 , 51, 3829–3839     

Preparation and nonlinear optical properties of novel Y-type polyesters with highly enhanced thermal stability of second harmonic generation

3,4-Di-(2′-hydroxyethoxy)benzylidenemalononitrile (3) was prepared and condensed with terephthaloyl chloride and adipoyl chloride to yield novel Y-type polyesters (4-5) containing 3,4-dioxybenzylidenemalononitrile groups as NLO-chromophores, which constituted parts of the polymer main-chains. The resulting polymers 4-5 are soluble in common organic solvents such as acetone and N,N-dimethylformamide. They showed thermal stability up to 300 °C in thermogravimetric analysis with glass-transition temperatures obtained from differential scanning calorimetry in the range 89-91 °C. The second harmonic generation (SHG) coefficients (d₃₃) of poled polymer films at the 1064 nm fundamental wavelength were around 2.47 pm/V. The dipole alignment exhibited high thermal stability even at 10 °C higher than T_g, and there is no SHG decay below 100 °C due to the partial main-chain character of polymer structure, which is acceptable for NLO device applications.     

Synthesis and characterization of interpenetrating polymer networks with nonlinear optical properties

We report the synthesis and characterization of interpenetrating polymer networks (IPNs) exhibiting nonlinear optical (NLO) properties. The network consists of aliphatic polycarbonate urethane (PCU) and poly(methyl methacrylate-co-N,N-disubstituted urea), with a nonlinear optical (NLO) chromophore incorporated into N,N-disubstituted urea. The full IPNs have only one T_g, as determined by differential scanning calorimetry (DSC), together with scanning electron microscopy (SEM) observations, suggest a single phase morphology. The thin films of IPNs are transparent and the unpoled samples produced second harmonic generation (SHG) signals at room temperature. This result indicates that the NLO chromophore is oriented noncentrosymmetrically during the IPN formation process and is tightly held between the permanent entanglements of the two component networks of the IPN. © 1996 John Wiley & Sons, Inc.     

Synthesis and electroluminescence properties of white‐light single polyfluorenes with high‐molecular weight by click reaction

We reported a new way to synthesize single‐chain white light‐emitting polyfluorene (WPF) with an increased molecular weight using azide‐alkyne click reaction. Four basic polymers with specific end‐capping, which exhibited high‐glass transition temperatures (T_g > 100 °C) and excellent thermal stability, were used as foundations of the WPF's synthesis; a blue‐light polymer (PFB2) end‐capped with azide groups can easily react with acetylene end‐capped polymers (PFB1, PFG1, and PFR1, which are emitting blue‐, green‐ and red‐light, respectively) to form triazole‐ring linkages in polar solvents such as N,N‐dimethylforamide/toluene co‐solvent at moderate temperature of 100 °C, even without metal‐catalyst. Several WPFs that consist of these four basic polymers in certain ratios were derived, and the polymer light‐emitting diode device based on the high‐molecular weight WPF was achieved and demonstrated a maximum brightness of 7551 cd/m² (at 12.5 V) and a maximum yield of 5.5 cd/A with Commission Internationale de l'Eclairage coordinates of (0.30, 0.33) using fine‐tuned WPF5 as emitting material. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011     

Synthesis,characterization, and thermal properties of ring‐opening metathesis polynorbornenes and their hydrogenated derivatives bearing various ester and cyano groups

Doubly functionalized polar norbornenes 3a – 3g substituted by both a variety of ester and cyano groups were polymerized by ring‐opening metathesis polymerization (ROMP) with a Ru carbene complex 2 bearing 3‐bromopyridine as a ligand (third generation Grubbs' catalyst) in a living manner. The successive hydrogenation of the main‐chain double bond in the synthesized living ROMP polymers 4a – 4g with a hydridoruthenium complex was exploited. The comparison of thermal properties of a series of ring‐opening metathesis polymers 4a – 4g with those of their hydrogenated derivatives 5a – 5g revealed the decrease of glass transition temperatures (T_g) but little change of the 5% decomposition temperature (T_d⁵). In all cases examined in this study, a decrease of T_g by hydrogenation was around 20–40 °C, regardless of the ester substitutents. In the presence of the additional PCy₃, triethylamine, and methanol after complete consumption of monomer 3a under the living ROMP condition, the tandem ROMP‐hydrogenation of the resulting polymer 4a generated in situ was attained under a H₂ (9.8 MPa) atmosphere at 80 °C to afford the hydrogenated polymer 5a , retaining the narrow polydispersity of 1.03. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 3314–3325 2008     

Preparation and properties of polybenzoxazine/poly(imide‐siloxane) alloys: In situ ring‐opening polymerization of benzoxazine in the presence of soluble poly(imide‐siloxane)s

Benzoxazine monomer (Ba) was blended with soluble poly(imide‐siloxane)s in various weight ratios. The soluble poly(imide‐siloxane)s with and without pendent phenolic groups were prepared from the reaction of 2,2′‐bis(3,4‐dicarboxylphenyl)hexafluoropropane dianhydride with α,ω‐bis(aminopropyl)dimethylsiloxane oligomer (PDMS; molecular weight = 5000) and 3,3′‐dihydroxybenzidine (with OH group) or 4,4′‐diaminodiphenyl ether (without OH group). The onset and maximum of the exotherm due to the ring‐opening polymerization for the pristine Ba appeared on differential scanning calorimetry curves around 200 and 240 °C, respectively. In the presence of poly(imide‐siloxane)s, the exothermic temperatures were lowered: the onset to 130–140 °C and the maximum to 210–220 °C. The exotherm due to the benzoxazine polymerization disappeared after curing at 240 °C for 1 h. Viscoelastic measurements of the cured blends containing poly(imide‐siloxane) with OH functionality showed two glass‐transition temperatures (T_g's), at a low temperature around ?55 °C and at a high temperature around 250–300 °C, displaying phase separation between PDMS and the combined phase consisting of polyimide and polybenzoxazine (PBa) components due to the formation of AB‐crosslinked polymer. For the blends containing poly(imide‐siloxane) without OH functionalities, however, in addition to the T_g due to PDMS, two T_g's were observed in high‐temperature ranges, 230–260 and 300–350 °C, indicating further phase separation between the polyimide and PBa components due to the formation of semi‐interpenetrating networks. In both cases, T_g increased with increasing poly(imide‐siloxane) content. Tensile measurements showed that the toughness of PBa was enhanced by the addition of poly(imide‐siloxane). Thermogravimetric analysis showed that the thermal stability of PBa also was enhanced by the addition of poly(imide‐siloxane). © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 2633–2641, 2001     

Facile synthesis of soluble aromatic poly(amide amine)s via C–N coupling reaction: Characterization,thermal, and optical properties

Aromatic poly(amide amine)s (APAAs), as novel high‐performance polymers, have been obtained by the condensation polymerization of N,N'‐bis(4‐bromobenzoyl)‐p‐phenylenediamine with two different primary aromatic diamines via palladium‐catalyzed aryl amination reaction. The structures of the polymers are characterized by means of FTIR, ¹H NMR spectroscopy, and elemental analysis, the results show a good agreement with the proposed structures. DSC and TGA measurements exhibit that polymers possess high glass transition temperature (T_g > 240 °C) and good thermal stability with high decomposition temperatures (T₅ > 400 °C). These novel polymers also display good solubility. In addition, due to its special structure, APAA‐2 is endowed with significantly strong photonic luminescence in N,N‐dimethylformamide and good electroactivity. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013 , 51, 4845–4852     

Synthesis and characterization of organic/inorganic hybrid star polymers of 2,2,3,4,4,4‐hexafluorobutyl methacrylate and octa(aminophenyl)silsesquioxane nano‐cage made via atom transfer radical polymerization

Well‐defined organic/inorganic hybrid fluorinated star polymers were synthesized via atom transfer radical polymerization (ATRP) of 2,2,3,4,4,4‐hexafluorobutyl methacrylate (HFBMA) using octa(aminophenyl)silsesquioxane (OAPS) nano‐cage as initiator. For this purpose, OAPS was transformed into ATRP initiator by reacting with 2‐bromoisobutyrylbromide. ATR polymerization of HFBMA was carried out in trifluorotoluene at 75 °C using CuCl/2,2‐bipyridine or N,N,N′,N″,N″‐pentamethyldiethylenetriamine as catalyst system. GPC and ¹H NMR data confirmed the synthesis of OAPS/PHFBMA hybrid star polymer. Kinetics of the ATR polymerization of HFBMA using OAPS nano‐cage initiator was also investigated. The OAPS/PHFBMA hybrid stars were found to be molecularly dispersed in solution (THF); however, TEM micrographs revealed the formation of spherical particles of ～ 120–180 nm by the OAPS/PHFBMA hybrid star polymer after solvent evaporation. Thermal characterization of the nanocomposites by differential scanning calorimetry (DSC) revealed a slightly higher glass transition temperature (T_g) (when compared with the linear PHFBMA) of higher molecular weight OAPS/PHFBMA hybrid star polymers. In contrast, lower T_g than the linear PHFBMA was observed for OAPS/PHFBMA of relatively lower molecular weight (but higher than the linear PHFBMA). Thermal gravimetric analysis (TGA) showed a significant retardation (by ～60 °C) in thermal decomposition of nanocomposites when compared with the linear PHFBMA. Additionally, surface properties were evaluated by measuring the contact angles of water on polymer surfaces. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7287–7298, 2008     

Synthesis and properties of a second‐order nonlinear optical side‐chain polyimide

A thermal stable aromatic polyimide (PI) with side‐chain second‐order nonlinear optical (NLO) chromophores has been developed. The PI was prepared by the ring‐opening polyaddition of 4,4′‐(hexafluoroisopropylidene)diphthalic anhydride with a new diamine having two N‐ethyl‐N‐[4‐[(6‐chlorobenzothiazol‐2‐yl)diazenyl]phenyl]‐2‐aminoethanol units as the NLO chromophore, followed by poling during or after the thermal imidization process. The resulting PI had number and weight‐average molecular weights (M_n, M_w) of 25,000 and 80,000, respectively, and a relatively high glass transition temperature of 180°C. The second harmonic coefficient (d₃₃) of PI at the wavelength of 1.064 μm was 138 pm/V (329.6 × 10⁻⁹ esu) and remained unchanged at elevated temperatures. The corona poling process of the NLO‐substituted poly(amic acid) to the PI was also studied in detail by measuring the second harmonic generation (SHG) from the polymer films. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 1321–1329, 1999     

New series of highly phenyl‐substituted polyfluorene derivatives for polymer light‐emitting diodes

A new series of highly phenyl‐substituted polyfluorene derivatives were synthesized and characterized. The resulting polymers were amorphous and showed excellent solubility in common organic solvents, such as chloroform, tetrahydrofuran, xylene, toluene, chlorobenzene, and so forth. All possessed satisfied thermal stability with glass‐transition temperatures (T_g's) in the range of 79–115 °C. They emitted blue light with photoluminescent (PL) maximum peaks at about 408–412 nm in thin films. The PL efficiencies of the polymer films were measured around 30–33%. The highly phenylated pendants improved the T_g of polyfluorene without forming defects in the polymers and reduced their tendency to form aggregate/excimers. Polymer light‐emitting diodes were fabricated from these polymers with the configuration of indium tin oxide/polyethylenedioxythiophene:polystyrene sulfonic acid/polymer/Ba/Al, which emitted bright blue light with maximum peaks at 418–420 nm. The maximum external quantum efficiencies of these devices were 0.41–0.6%. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2985–2993, 2004     

Synthesis and nonlinear optical properties of novel Y-type polyimides with enhanced thermal stability of dipole alignment

2,3-Bis-(3,4-dicarboxyphenylcarboxyethoxy)-4′-nitrostilbene dianhydride (4) was prepared and reacted with 1,4-phenylenediamine, 4,4′-oxydianiline, 4,4′-diaminobenzanilide and 4,4′-(hexafluoroisopropylidene)dianiline to yield novel polyimides 5-8 containing 2,3-dioxynitrostilbenyl groups as NLO-chromophores, which constituted parts of the polymer backbones. The resulting polyimides 5-8 were soluble in polar solvents such as acetone and DMF. Polymers 5-8 showed a thermal stability up to 300 °C in TGA thermograms with T_g values obtained from DSC thermograms in the range of 135-160 °C. The SHG coefficients (d₃₃) of poled polymer films at the 1064 cm⁻¹ fundamental wavelength were around 5.26 × 10⁻⁹ esu. The dipole alignment exhibited exceptionally high thermal stability even at 30 °C higher than T_g and there was no SHG decay below 170-190 °C due to the partial main chain character of polymer structure, which was acceptable for NLO device applications.     

Synthesis and characterization of phthalazinone containing poly(arylene ether)s via a novel N–C coupling reaction

High‐molecular‐weight poly(phthalazinone)s with very high glass‐transition temperatures (T_g's) were synthesized via a novel N–C coupling reaction. New bisphthalazinone monomers ( 7a–e ) were synthesized from 2‐(4‐chlorobenzoyl) phthalic acid in two steps. Poly(phthalazinone)s, having inherent viscosities in the range of 0.34–0.91 dL/g, were prepared by the reaction of the bis(phthalazinone) monomers with an activated aryl halide in a dipolar aprotic solvent in the presence of potassium carbonate. The poly(phthalazinone)s exhibited T_g's greater than 230 °C. polymer 8b synthesized from diphenyl biphenol and bis(4‐flurophenyl) sulfone demonstrated the highest T_g of 297 °C. Thermal stabilities of the poly(phthalazinone)s were determined by thermogravimetric analysis. All the poly(phthalazinone)s showed a similar pattern of decomposition with no weight loss below 450 °C in nitrogen. The temperatures of 5% weight loss were observed to be about 500 °C. The poly(phthalazinone)s containing 4,4′‐isopropylidenediphenol and 4,4′‐(hexafluoroisopropylidene) diphenol and diphenyl ether linkage were soluble in chlorinated solvents such as chloroform. Other poly‐(phthalazinone)s were soluble in dipolar aprotic solvents such as N,N′‐dimethylacetamide. The soluble poly(phthalazinone)s can be cast as flexible films from solution. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2481–2490, 2003