Synthesis and Properties of Carbazole-containing Copolymers from Bis[3-(4-fluorobenzoyl)carbazole] Methane

A novel difluoride containing carbazole groups was designed. Two series of polycarbazoles based on the novel monomer were synthesized via C-N coupling reactions with either 4,4′-biphenol or bisphenol A. Copolymers were obtained with 4,4′-difluorobenzophenone or bis(4-fluorophenyl) sulfone as comonomer. The solubilities of the poly(carbazole ketones)s were poor, but the poly(carbazaole sulfones)s all dissolved in NMP, DMSO and DMAC. Tough films of poly(carbazole sulfones)s could be easily cast from NMP solutions. The viscosities of poly(carbazole sulfones)s were 0.72 ～ 0.90 dL/g. The T_gs of polymers ranged from 162.4°C to 258.9°C. The temperatures of 5% wt loss ranged from 460°C to 509°C. UV-Vis absorptions and blue light emissions properties are also presented.     

Synthesis and study of self-organization of organo-inorganic nanostructures based on cationic poly(meth)acrylates and molybdenum disulfide single layers

Poly(meth)acrylates of three types, namely, regular homopolymers containing side-chain tetraalkylammonium ionic groups with alkyl radicals of various lengths (C₆ and C₁₆), a copolymer with statistically distributed ionic and long-chain (C₁₈) alkyl groups, and a block copolymer of the same composition in which alkylammonium and alkyl groups are located in separate blocks, are synthesized with the use of controlled radical polymerization processes. The interaction of the polymers with molybdenum disulfide singlelayer dispersions yields self-organized organic-inorganic nanocomposites containing up to 40% polymer. As evidenced by powder X-ray diffraction and high-resolution transmission electron microscopy structural studies of the composites, they possess a crystalline layered structure with interlayer distances depending on the composition and structure of the polymer. Structures with the most regular alternation of organic and inorganic layers are formed in the case of homopolymers. The orientation of their alkylammonium fragments relative to MoS₂ layers depends on the length of the alkyl radical and corresponds to their parallel (C₆) or perpendicular (C₁₆) arrangement.     

Cyclic and linear poly(ferrocenylene alkylene)s synthesized from addition‐condensation polymerization of ferrocene with aldehydes

Oligo‐ and poly(ferrocenylene alkylene)s, [Fe(C₅H_5‐x)(C₅H_5‐y)CHR]_n (x = y = 1 or x = 2, y = 0; R = alkyl, aryl), were synthesized by Lewis acid‐promoted addition‐condensation polymerization of ferrocene with aldehydes. The reaction of alkyl aldehydes, such as n‐hept‐CHO, EtCHO and nBuCHO, with ferrocene yields a mixture of the cyclic and linear poly(ferrocenylene alkylene)s, while aryl aldehyde, such as C₆F₅CHO, CF₃C₆H₄‐4‐CHO and MeC₆H₄‐4‐CHO, forms the linear polymers exclusively. The linear polymer has terminal ? Fe(C₅H₄)(C₅H₅) and ? CH₂Aryl groups, which are characterized by high resolution mass spectroscopy. Results of addition‐condensation polymerization of ferrocenemethanol catalyzed by BF₃ indicate that the propagating polymer of the above addition‐condensation polymerization contains terminal 1‐hydroxyalkyl‐ferrocenylene group, ? Fe(C₅H₄)[C₅H₄{CH(OH)R}]. The trimer prepared from ferrocene and paraformaldehyde dimethylacetal contains 1,1′‐, 1,2‐, and 1,3‐ferrocenylene units, suggesting that the polymers obtained from alkyl and aryl aldehydes are also composed of these structural units. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 3627–3635     

A New Poly(fluorene‐co‐carbazole) with a Large Substituent Group at the 9‐Position of the Carbazole Moiety: An Efficient Blue Emitter

Summary: A new poly(fluorene‐co‐carbazole) (PFC‐1) with a large substituent group (ADN, a naphthalene‐anthracene derivative moiety) at the 9‐position of carbazole was synthesized. Compared with poly(fluorene‐co‐carbazole)s that have an alkyl substituent group at the 9‐position of the carbazole, the UV‐vis absorption (or photoluminescent emission) peaks of PFC‐1 are in almost the same position both in solution and in the solid state, whereas films of the former give peaks at longer wavelengths than those in solution. The photoluminescent (PL) spectra of PFC‐1 indicate that the attachment of ADN to the poly(fluorene‐co‐carbazole)s gives rise to an efficient blue emission from non‐aggregated ADN. There is no difference evident between PFC‐1 and other reported poly(fluorene‐co‐carbazole)s in PL quantum yield, thermostability, and electrochemical behavior, which suggests that PFC‐1 is an efficient blue emitter.

UV‐Vis spectra of the poly(fluorene‐co‐carbazole) (PFC‐1), with a large substituent group (ADN, a naphthalene‐anthracene derivative moiety) at the 9‐position of carbazole, in toluene and in the film.     

Synthesis and miscibility studies of [60]fullerenated poly(2‐hydroxyethyl methacrylate)

[60]Fullerenated poly(2‐hydroxyethyl methacrylate)s containing 0.6–3.0 wt % C₆₀ were synthesized. These polymers are soluble in methanol and N,N‐dimethylformamide (DMF). [60]Fullerenated poly(2‐hydroxyethyl methacrylate)s with higher C₆₀ contents are only sparingly soluble in DMF and virtually insoluble in other organic solvents. A loading of 1.2 wt % C₆₀ in poly(2‐hydroxyethyl methacrylate) does not greatly affect its miscibility with poly(N‐vinyl‐2‐pyrrolidone), poly(1‐vinylimidazole), and poly(4‐vinylpyridine). © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 1157–1166, 2002     

Polymerization of surface-active monomers. VIII. Tacticity of polymers prepared by radical polymerization of quaternary salts of dimethylaminoethyl methacrylate in micellar and isotropic media

The effect of monomer micellization on the polymerization was studied from the standpoint of stereochemistry in the polymerization. Quaternary salts (C_nBr) of dimethylaminoethyl methacrylate with n-alkyl bromide having N (=4, 8 and 12) carbon atoms were polymerized with radical initiators in isotropic and anisotropic media and the resulting polymers were converted to poly (methyl methacrylate) (PMMA) to determine their tacticity. Tacticities of poly (C₁₂Br)s were little affected by initiators and solvents used for their preparations. There was little dependence of the tacticities on alkyl chain length (N) for poly (C_nBr)s prepared in water and dimethylformamide (DMF). Most of polymers produced here conformed to Bernoullian propagation statistics and a definite difference was not found in the tacticities between the polymers prepared in isotropic and anisotropic media. From the results obtained here it was deduced that the micellar aggregation has little influence upon the stereochemistry in the polymerization of the quaternary monomers. © 1994 John Wiley & Sons, Inc.     

pH‐sensitive hemolysis by random copolymers of alkyl acrylates and acrylic acid

We have been designing and synthesizing synthetic polymers that mimic viral fusogenic peptides, which contain peptide residues having alkyl groups and carboxyl groups. We have synthesized two different types of such polymers, and their abilities to hemolyse red blood cells at pH 7.4 and 5.5 are compared here. The polymers are poly(2‐alkylacrylic acid)s such as poly(2‐propylacrylic acid), and random copolymers of poly(alkyl acrylate‐co‐acrylic acid) where the alkyl group is propyl or butyl. We have found that the poly(2‐alkylacrylic acid)s such as poly(2‐propylacrylic acid) are significantly more hemolytic at acidic pH than the random copolymers of equivalent propyl and carboxyl contents.     

Synthesis and luminescence of poly(phenylacetylene)s with pendant iridium complexes and carbazole groups

Poly(phenylacetylene)s containing pendant phosphorescent iridium complexes have been synthesized and their electrochemical, photo‐ and electroluminescent properties studied. The polymers have been synthesized by rhodium‐catalyzed copolymerization of 9‐(4‐ethynylphenyl)carbazole (CzPA) and phenylacetylenes (C∧N)₂Ir(κ²‐O,O′‐MeC(O)CHC(O)C₆H₄C?CH‐4) (C∧N = κ²‐N,C¹‐2‐(pyridin‐2‐yl)phenyl (Ir^ppyPA) or κ²‐N,C¹‐2‐(isoquinolin‐1‐yl)phenyl (Ir^piqPA)). In addition, organic poly(phenylacetylene)s with pendant carbazole groups have been synthesized by rhodium‐catalyzed copolymerization of CzPA and 1‐ethynyl‐4‐pentylbenzene. Complex (C∧N)₂Ir(κ²‐O,O′‐MeC(O)CHC(O)Ph) (Ir^piqPh; C∧N = 2‐(isoquinolin‐1‐yl)phenyl‐κ²‐N,C¹) was prepared and characterized. While the copolymers of the Ir^ppy series were weakly phosphorescent, those of the Ir^piq series displayed at room temperature intense emissions from the carbazole (fluorescence) and iridium (phosphorescence) emitters, being the latter dominant when the spectra were recorded using polymer films. Triple layer OLED devices employing copolymers of the Ir^piq series or the model complex Ir^piqPh yielded electroluminescence with an emission spectra originating from the iridium complex and maximum external quantum efficiencies of 0.46% and 2.99%, respectively. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3744–3757, 2010     

Synthesis and characterization of novel low‐bandgap triphenylamine‐based conjugated polymers with main‐chain donors and pendent acceptors for organic photovoltaics

A series of novel low‐bandgap triphenylamine‐based conjugated polymers ( PCAZCN , PPTZCN , and PDTPCN ) consisting of different electron‐rich donor main chains (N‐alkyl‐2,7‐carbazole, phenothiazine, and cyclopentadithinopyrol, respectively) as well as cyano‐ and dicyano‐vinyl electron‐acceptor pendants were synthesized and developed for polymer solar cell applications. The polymers covered broad absorption spectra of 400–800 nm with narrow optical bandgaps ranging 1.66–1.72 eV. The highest occupied molecular orbital and lowest unoccupied molecular orbital levels of the polymers measured by cyclic voltammetry were found in the range of ?5.12 to ?5.32 V and ?3.45 to ?3.55 eV, respectively. Under 100 mW/cm² of AM 1.5 white‐light illumination, bulk heterojunction photovoltaic devices composing of an active layer of electron‐donor polymers ( PCAZCN , PPTZCN , and PDTPCN ) blended with electron‐acceptor [6,6]‐phenyl‐C₆₁‐butyric acid methyl ester or [6,6]‐phenyl‐C₇₁‐butyric acid methyl ester (PC₇₁BM) in different weight ratios were investigated. The photovoltaic device containing donor PCAZCN and acceptor PC₇₁BM in 1:2 weight ratio showed the highest power conversion efficiency of 1.28%, with V_oc = 0.81 V, J_sc = 4.93 mA/cm², and fill factor = 32.1%. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010     

Syntheses and characterization of carbazole based new low‐band gap copolymers containing highly soluble benzimidazole derivatives for solar cell application

Newly designed 2H‐benzimidazole derivatives which have solubility groups at 2‐position have been synthesized and incorporated into two highly soluble carbazole based alternating copolymers, poly[2,7‐(9‐(1′‐octylnonyl)‐9H‐carbazole)‐alt‐5,5‐(4′,7′‐di(thien‐2‐yl)‐2H‐benzimidazole‐2′‐spirocyclohexane)] (PCDTCHBI) and poly[2,7‐(9‐(1′‐octylnonyl)‐9H‐carbazole)‐alt‐5,5‐(4′,7′‐di(thien‐2‐yl)‐2H‐benzimidazole‐2′‐spiro‐4′′‐((2′′′‐ethylhexyl)oxy)‐cyclohexane)] (PCDTEHOCHBI) for photovoltaic application. These alternating copolymers show low‐band gap properties caused by internal charge transfer from an electron‐rich unit to an electron‐deficient moiety. HOMO and LUMO levels are –5.53 and –3.86 eV for PCDTCHBI, and –5.49 and –3.84 eV for PCDTEHOCHBI, respectively. Optical band gaps of PCDTCHBI and PCDTEHOCHBI are 1.67 and 1.65 eV, respectively. The new carbazole based the 2H‐benzimidazole polymers show 0.11–0.13 eV lower values of band gaps as compared to that of carbazole based benzothiadiazole polymer, poly[N‐9′‐heptadecanyl‐2,7‐carbazole‐alt‐5,5‐(4′,7′‐di‐2‐thienyl‐2′,1′,3′‐benzothiadiazole)] (PCDTBT), while keeping nearly the same deep HOMO levels. The power conversion efficiencies of PCDTCHBI and PCDTEHOCHBI blended with [6,6]phenyl‐C₇₁‐butyric acid methyl ester (PC₇₁BM) are 1.03 and 1.15%, respectively. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011     

Mass spectrometric investigation of the aggregation and coalescence of fullerenes in C60-modified poly(N-vinylcarbazole) by UV-laser ablation

The phenomena of aggregation and coalescence of fullerenes in the UV-laser ablation time-of-flight mass spectrometric investigation of C₆₀-modified poly(N-vinylcarbazole) both in the positive and in the negative ion channels have been observed. The results indicate that in C₆₀ chemically modified PVK (C₆₀–PVK) copolymer the nascent fullerene fragments ruptured from main chain can easily coalesce into large fullerenes through collisions, whereas in the C₆₀-doped PVK the aggregation and coalescence of C₆₀ were relative weak due to nonbounding action and incomplete charge transfer behavior between C₆₀ and PVK. Furthermore, the photoinduced electron transfer behavior between C₆₀ and carbazole units in the C₆₀ chemically modified poly(N-vinylcarbazole) in benzonitrile by laser flash photolysis at 355 nm has also been investigated. Efficiency of the anion radical of C₆₀ in copolymer at 1080 nm is higher than that of the C₆₀-doped poly(N-vinylcarbazole) polymers. The formation of a C₆₀ radical anion may be ascribed to photoinduced electron transfer between C₆₀ pendanted on the main chain backbone and the inter-, and intrachain carbazole units in the copolymer. © 1997 John Wiley & Sons, Inc. 35 : 1185–1190, 1997     

Synthesis and polymerization of 2-alkylanilines

2-Alkylanilines with alkyl groups in the range of 4–15 carbon atoms were synthesized via a known method as well as via a more general path which should allow the introduction of a larger variety of substituted alkyl groups into the ortho position of aniline, e.g., alkenyl or OH, NH₂, COOH, and phenyl functionality. Polymerization was found to be achievable according to a method previously described for unsubstituted aniline, i.e., chemically with Cu(ClO₄)₂ · 6H₂O in acetonitrile. Intrinsic viscosities of the obtained poly(2-alkylaniline)s lay between 0.10 and 0.26 dL/g (97% H₂SO₄ at 30°C). The dc conductivity of the HCl salts decreased with increasing length of the alkyl side chains from 1 S/cm (polyaniline) over 3 X 10^?4 S/cm [poly(2-butylaniline)] to 1 X 10^?6 S/cm poly(tridecylaniline). Further characterization of the polymers were performed by means of UV/VIS/NIR-and-IR spectroscopy, in dilute solutions or as KBr pellets, respectively, and by solubility tests. © 1993 John Wiley & Sons, Inc.     

Synthesis of n‐alkyl methacrylate polymers with pendant carbazole moieties and their derivatives

New methacrylate monomers with carbazole moieties as pendant groups were synthesized by multistep syntheses starting from carbazoles with biphenyl substituents in the aromatic ring. The corresponding polymers were prepared using a free‐radical polymerization. The novel polymers contain N‐alkylated carbazoles mono‐ or bi‐substituted with biphenyl groups in the aromatic ring. N‐alkyl chains in polymers vary by length and structure. All new polymers were synthesized to evaluate the structural changes in terms of their effect on the energy profile, thermal, dielectric, and photophysical properties when compared to the parent polymer poly(2‐(9H‐carbazol‐9‐yl)ethyl methacrylate). According to the obtained results, these compounds may be well suited for memory resistor devices. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 70–76     

New carbazole‐based conjugated polymers containing pyridylvinyl thiophene units for polymer solar cell applications: Morphological stabilization through hydrogen bonding

We have synthesized two conjugated polymers ( P1 , P2 ) containing alternating electron‐donating and ‐accepting units, based on N‐alkyl‐2,7‐carbazole, 4,7‐di(thiophen‐5‐yl)‐2,1,3‐benzothiadiazole and 3‐[2‐(4‐pyridyl)vinyl]thiophene units. These conjugated polymers contained different contents of pyridine units, which were incorporated to form hydrogen bonds with [6,6]‐phenyl‐C₆₁‐butyric acid (PCBA). When these hydrogen bonding interactions were present in the polymer thin films, their thermal stability improved; deterioration, which occurred through aggregation of PCBA methyl ester after lengthy annealing times, was also suppressed. The power conversion efficiency of a device incorporating the film featuring hydrogen bonding interactions remained at 75% of the original value after thermal annealing for 5 h at 140 °C. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011     

A single‐layer approach to electrochromic materials

This study is focused on the development of electrochromic (EC) materials that could be incorporated into electrically‐driven switchable devices such as electrochromogenic glasses. The ultimate goal of this research is to depart from the complexity of the EC device construction which is in use today. Such construction consists of three layers each of them incorporating a specific functionality: the electrochromophore, the electrolyte and the ion storage, assembled between two transparent or reflective electrodes. In most of these conventional devices the electrolyte layer is a liquid or a gel. Since solid‐state EC devices are of high commercial interest, we are exploring various avenues to reduce the number of layers to one layer that is all‐solid and electrochromically/electrolytically and ionically functional. The design strategy is based on the use of polymers such as poly(epichlorohydrin‐co‐ethylene oxide), poly(vinyl butyral) and poly(ethylene‐co‐methacrylic acid) ionomer, to which EC properties were introduced by grafting reactions with specifically synthesized carbazole derivatives. A combination of analytical techniques was used to characterize the monomers and the carbazole‐grafted polymers. A proof of concept was demonstrated for a single‐layer, all‐solid‐state EC device consisting of a film of poly(ECH‐co‐EO) containing pendent carbazole groups, assembled between two transparent electrodes, Sn‐doped In₂O₃ oxide‐coated glasses. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011     

Polymerization of surface-active monomers. II. Polymerization of quarternary alkyl salts of dimethylaminoethyl methacrylate with a different alkyl chain length

The cationic monomers (C_NBr), obtained by quarternization of dimethylaminoethyl methacrylate with n-alkyl bromide containing varying carbon number (N = 4, 8, 12, 14, and 16) were polymerized with radical initiators in water and various organic solvents. The degree of polymerization of the resulting polymers was determined by GPC measurements on poly(methyl methacrylate) samples derived from them. The rate of polymerization of the micelle-forming monomers (N = 8, 12, 14, and 16) in water increases with increasing a chain length of alkyl group, whereas it is little dependent on N in isotropic solution in dimethylformamide. The data on the degree of polymerization for the polymers of C₄Br, C₈Br, and C₁₂Br show that the polymerization of C₁₂Br with azo initiators in water and benzene gives polymers with a very high degree of polymerization. The results obtained here suggest that highly developed or relatively rigid, aggregated structures of monomers in solution are responsible for the formation of the polymers with a very high degree of polymerization, in addition to an enhanced rate of polymerization. Also considered are the relation of the molecular weight of poly(C₁₂Br) to the viscosity data in chloroform and methanol.     

Aggregation-induced emission active 3,6-bis(1,2,2-triphenylvinyl)carbazole and bis(4-(1,2,2-triphenylvinyl)phenyl)amine-based poly(acrylates) for explosive detection

Four novel aggregation-induced emission (AIE)-active poly(acrylates), in which AIE-active luminogens 3,6-bis(1,2,2-triphenylvinyl)carbazole (BTPC) and bis(4-(1,2,2-triphenylvinyl)phenyl)amine (BTPPA) were linked to the polymer backbone via a flexible alkyl chain, were synthesized in high yields. Spectrofluorometric analysis of polymer nano-aggregates in tetrahydrofuran/water revealed that PTPPA-based polymers gave more sensitive fluorescence response to nitro-aromatics including 2,4,6-trinitrotoluene than BTPC-based polymers. Paper probes were also fabricated for solid-state detection of explosives. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 672–681     

Synthesis of fluorine‐containing star‐shaped poly(vinyl ether)s via arm‐linking reactions in living cationic polymerization

Various types of fluorine‐containing star‐shaped poly(vinyl ether)s were successfully synthesized by crosslinking reactions of living polymers based on living cationic polymerization. Star polymers with fluorinated arm chains were prepared by the reaction between a divinyl ether and living poly(vinyl ether)s with fluorine groups (C₄F₉, C₆F₁₃, and C₈F₁₇) at the side chain using cationogen/Et_1.5AlCl_1.5 in a fluorinated solvent (dichloropentafluoropropanes), giving star‐shaped fluorinated polymers in high yields with a relatively narrow molecular weight distribution. The concentration of living polymers for the crosslinking reaction and the molar feed ratio of a bifunctional vinyl ether to living polymers affected the yield and molecular weight of the star polymers. Star polymers with block arms were prepared by a linking reaction of living block copolymers of a fluorinated segment and a nonfluorinated segment. Heteroarm star‐shaped polymers containing two‐ or three‐arm species were synthesized using a mixture of different living polymer species for the reaction with a bifunctional vinyl ether. The obtained polymers underwent temperature‐induced solubility transitions in various organic solvents, and their concentrated solutions underwent sol–gel transitions, based on the solubility transition of a thermoresponsive fluorinated segment. Furthermore, a slight amount of fluorine groups were shown to be effective for physical gelation when those were located at the arm ends of a star polymer. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012     

A new class of multifunctional poly(1, 6-heptadiyne)-based materials by metathesis polymerization

A new class of multifunctional polymers based on poly(1, 6-heptadiyne) derivatives with various functional groups such as carbazole unit for photoconductive polymers and nonlinear optical (NLO) chromophores for NLO polymers were synthesized by metathesis polymerization. The polymerizations were carried out with MoCl₅- and WCl₆-based catalysts. The catalytic activity of MoCl₅ was found to be greater than that of WCl₆. The resulting polymers exhibited photoconductivity and large optical nonlinearity. These conjugated polymers have good solubility in common organic solvents, long-term stability toward air oxidation, and high electrical conductivity.     

Polymer Structure‐Guided Self‐Assisted Preparation of Poly(ester‐thioether)‐Based Hollow Porous Microspheres and Hierarchically Interconnected Microcages for Drug Release

Porous polymer microspheres (PPMs) have been widely applied in various biomedical fields. Herein, the self‐assisted preparation of poly(ester‐thioether)‐based porous microspheres and hierarchical microcages, whose pore sizes can be controlled by varying the polymer structures, is reported. Poly(ester‐thioether)s with alkyl side chains (carbon atom numbers were 2, 4, and 8) can generate hollow porous microspheres; the longer alkyl chain length, the larger pore size of microspheres. The allyl‐modified poly(ester‐thioether) (PHBDT‐g‐C₃) can form highly open, hierarchically interconnected microcages. A formation mechanism of these PPMs is proposed; the hydrophobic side chains‐mediated stabilization of oil droplets dictate the droplet aggregation and following solvent evaporation, which is the key to the formation of PPMs. The hierarchically interconnected microcages of PHBDT‐g‐C₃ are due to the partially crosslinking of polymers. Pore sizes of PPMs can be further tuned by a simple mixing strategy of poly(ester‐thioether)s with different pore‐forming abilities. The potential application of these PPMs as H₂O₂‐responsive vehicles for delivery of hydrophobic (Nile Red) and hydrophilic (doxorubicin hydrochloride) cargos is also investigated. The microspheres with larger pore sizes show faster in vitro drug release. The poly(ester‐thioether)‐based polymer microspheres can open a new avenue for the design of PPMs and provide a H₂O₂‐responsive drug delivery platform.