Synthesis,characterization, and electrical properties of a diazodiphenylene‐bridged Cu–phthalocyanine polymer

A diazodiphenylene‐bridged Cu–phthalocyanine polymer was synthesized from the diazonium salt of bensidine and the Cu(II) 1,8,15,22‐tetraaminophthalocyanine complex and characterized with Fourier transform infrared, ultraviolet–visible spectroscopy, and elemental analysis. The polymer was partially soluble in organic solvents such as dimethylformamide and tetrahydrofuran. The molecular weight of the soluble part of the polymer was investigated with ebullioscopy and viscosimetry methods in tetrahydrofuran. Both methods showed that the molecular weight of the polymer was much larger than that of the complex. The conductivity of the samples was measured with a four‐prop conductivity measuring device. Iodine and hydrogen chloride were doped to the polymer, and an increase of about 10⁴ S cm^?1 in the electrical conductivity was observed. The cyclic voltammogram of the diazodiphenylene‐bridged Cu–phthalocyanine polymer in contact with a LiClO₄ electrolyte exhibited two reductions and two reoxidations with high reversibility and electrochemical stability. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5692–5698, 2006     

Highly stereo‐efficient synthesis and luminescence properties of novel trans‐regular vinylene– silylene–thiophene polymers

The novel trans‐stereo‐regular silylene–thiophene derivatives ( 4 , 5 ) with perfect consecutive silylene–arylene–silylene–vinylene linkage were synthesized via silylative coupling polycondensation of 2,5‐bis(vinyldimethylsilyl)thiophene ( 2 ) or 5,5′‐bis(vinyldimethylsilyl)‐2,2′‐bithiophene ( 3 ) catalyzed by ruthenium‐hydride complex [RuHCl(CO)(PCy₃)₂] ( 1 ). Their spectroscopic, absorption, and luminescence properties were characterized and compared with those of model compounds containing thiophene or bithiophene chromophores. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 127–137, 2008     

温度敏感树形聚合物

温度敏感树形聚合物结合了温敏聚合物对温度具有响应行为的特点以及树形聚合物非线形构造的方式、大尺度、结构易于调节和功能化等特征,在智能材料和生物医药等领域有着重要的研究价值和应用前景。此类聚合物可以通过在树形聚合物表面引入温敏基元、控制聚合物结构的亲疏水比例以及采用温敏基元直接构筑聚合物等方式形成,其温敏性可以通过调控聚合物内部或外部基团的亲疏水性、树枝化基元代数、树形构造方式等得以实现与控制。此外,树形聚合物独特的拓扑结构赋予其与线形聚合物不同的温敏行为及脱水机理。本文综述了包括温敏树枝状大分子、温敏树枝化聚合物、温敏超支化聚合物等不同类型温敏树形聚合物近年来的研究进展,重点介绍这些聚合物的合成方法、温敏行为和拓扑结构对温敏行为的影响,以及在纳米材料、生物医用、分子传感器等方面的应用研究。     

Recent advances in the syntheses of radical‐containing macromolecules

Tailor‐made polymers containing specific chemical functionalities have ushered in a number of emerging fields in polymer science. In most of these next‐generation applications the focus of the community has centered upon closed‐shell macromolecules. Conversely, macromolecules containing stable radical sites have been less studied despite the promise of this evolving class of polymers. In particular, radical‐containing macromolecules have shown great potential in magnetic, energy storage, and biomedical applications. Here, the progress regarding the syntheses of open‐shell containing polymers are reviewed in two distinct subclasses. In the first, the syntheses of radical polymers (i.e., materials composed of non‐conjugated macromolecular backbones and with open‐shell units present on the polymer pendant sites) are described. In the second, polyradical (i.e., macromolecules containing stabilized radical sites either within the macromolecular backbone or those containing radical sites that are stabilized through a large degree of conjugation) synthetic schemes are presented. Thus, the state‐of‐the‐art in open‐shell macromolecular syntheses will be reported and future means by which to advance the current archetype will be discussed. By detailing the synthetic pathways possible for, and the inherent synthetic limitations of, the creation of these functional polymers, the community will be able to extend the bounds of the radical‐containing macromolecular paradigm. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 1875–1894     

Design of molecular magnets

The conventional magnetic materials used in present-day technology, such as Fe, Fe₂O₃, Cr₂O₃, SmCo₅, Nd₂Fe₁₄B, etc. are all atom-based, whose synthesis requires high-temperature routes. Employing ambient-temperature synthetic organic chemistry, it has become possible to engineer a bulk molecular material with long-range magnetic order, primarily due to the weak nature of intermolecular interactions in it. Typical synthetic approach to design molecule-based magnets consists of choosing molecular precursors, each bearing an unpaired spin, and assembling them in such a way that there is no compensation of spins at the scale of the crystal lattice. Magnetism being a co-operative effect, the spin-spin interaction must extend to all the three dimensions, either through space or through bonds. Specific occurrence of ‘spin delocalisation’ and ‘spin polarisation’ in molecular lattices is helpful in bringing about ferromagnetic interaction by facilitating necessary intermolecular exchange interactions. Since the first successful synthesis of molecular magnets in 1986, a large variety of them have been synthesized, which can be classified on the basis of the chemical nature of the magnetic units involved: organic systems, metal-based systems, hetero-bimetallic assemblies, or mixed organic-inorganic systems. The design of molecular magnets has also opened the doors for the unique possibility of designing polyfunctional molecular materials, such as magnets exhibiting second-order optical nonlinearity, liquid crystalline magnets, or chiral magnets. Solubility of molecular magnets, their low density and biocompatibility are attractive features. Being weakly colored, unlike the opaque classic magnets, possibilities of photomagnetic switching can be envisaged. Persistent efforts continue to design the ever-elusive polymer magnets for applications in industry. While providing a brief overview of the field of molecular magnetism, we highlight some recent developments, with emphasis on a few studies from the author's own lab.     

Polysoaps with fluorocarbon hydrophobic chains

A series of amphiphilic copolymers is prepared by copolymerization of choline methacrylate with 1,1,2,2-tetrahydroperfluorooctyl methacrylate in varying amounts. The copolymers bearing fluorocarbon chains are studied concerning their effects on viscosity, solubilization and surface activity in aqueous solution, exhibiting a general behavior characteristic for polysoaps. The results are compared with the ones obtained for an analogous series of amphiphilic copolymers bearing hydrocarbon chains.     

New Azo Chromophore‐Containing Conjugated Polymers: Facile Synthesis by Using “Click” Chemistry and Enhanced Nonlinear Optical Properties Through the Introduction of Suitable Isolation Groups

A new series of azobenzene‐containing polyfluorenes have been successfully prepared through polymer reactions by the utilization of “click” chemistry. All the polymers were well characterized and soluble in common solvents. By the application of the concept of “suitable isolation group”, the macroscopic nonlinear optical (NLO) properties of the polymers could be boosted to as large as three times that of the polymer without isolation moieties. Also, all the polymers were thermally stable, and demonstrated good procesability, coupled with improved optical transparency. Thus, they are good candidates for the practical applications as new photonic materials.

     

Functional Water Soluble Polymers with Ability to Bind Metal Ions

Water-soluble polymers containing amine, carboxylic acid, and sulfonic acid groups were investigated as polychelatogens through the liquid phase polymer-based retention, LPR technique, under different experimental conditions. The metal ions investigated are: Ag(I), Cu(II), Co(II), Ni(II), Ca(II), Hg(II), and Cr(III). An important effect of the pH and the ligand type was observed on the metal ion retention. As the pH increases the metal ion retention increases. Two types of metal ion interactions are involved: coordination and electrostatic.     

含胍基抗菌聚合物的合成及应用

开发能与细菌非特异性结合的新型抗菌剂是解决细菌感染难题的方法之一。本文首先介绍了一种具有持久广谱高效抗菌性、无真核细胞毒性和细菌很难产生耐药性的含胍基抗菌聚合物;接着详细介绍了含胍基抗菌聚合物与细菌非特异性静电结合的抗菌机理;然后重点评述了主链含胍基抗菌聚合物、侧链含胍基抗菌聚合物以及表面接枝含胍基抗菌聚合物的设计理念、合成方法和抗菌性能;最后对新型含胍基抗菌聚合物的可控合成策略及应用前景进行了展望。     

Synthesis and characterization of cyclopentadithiophene‐based low bandgap copolymers containing electron‐deficient benzoselenadiazole derivatives for photovoltaic devices

We have synthesized two cyclopentadithiophene (CDT)‐based low bandgap copolymers, poly[(4,4‐bis(2‐ethyl‐hexyl)‐4H‐cyclopenta[2,1‐b:3,4‐b′]dithiophene‐2,6‐diyl)‐alt‐(benzo[c][1,2,5]selenadiazole‐4,7‐diyl)] (PCBSe) and poly[(4,4‐bis(2‐ethyl‐hexyl)‐4H‐cyclopenta[2,1‐b:3,4‐b′]dithiophene‐2,6‐diyl)‐alt‐(4,7‐dithiophen‐2‐yl‐benzo[c][1,2,5]selenadiazole‐5,5′‐diyl)] (PCT2BSe), for use in photovoltaic applications. Through the internal charge transfer interaction between the electron‐donating CDT unit and the electron‐accepting benzoselenadiazole, we realized exceedingly low bandgap polymers with bandgaps of 1.37–1.46 eV. The UV–vis absorption maxima of PCT2BSe were subjected to larger hypsochromic shifts than those of PCBSe, because of the distorted electron donor–acceptor (D–A) structures of the PCT2BSe backbone. These results were supported by the calculations of the D–A complex using the ab initio Hartree‐Fock method with a split‐valence 6‐31G* basis set. However, PCT2BSe exhibited a better molar absorption coefficient in the visible region, which can lead to more efficient absorption of sunlight. As a result, PCT2BSe blended with [6,6]‐phenyl‐C₆₁‐butyric acid methyl ester (PC₆₁BM) exhibited a better photovoltaic performance than PCBSe because of the larger spectral overlap integral with respect to the solar spectrum. Furthermore, when the polymers were blended with PC₇₁BM, PCT2BSe showed the best performance, with an open circuit voltage of 0.55 V, a short‐circuit current of 6.63 mA/cm², and a power conversion efficiency of 1.34% under air mass 1.5 global illumination conditions. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1423–1432, 2010     

Regioregular poly[3‐(4‐alkoxyphenyl)thiophene]s

An easy synthetic procedure for soluble poly[3‐(4‐alcoxyphenyl)thiophene]s is reported. The polymers present a high regioregularity degree as determined by both UV–vis spectra and ¹H and ¹³C NMR analysis. Furthermore, X‐ray powder diffraction analysis performed on films of the polymers suggests a π‐stacked packing structure of the macromolecules. Electrical characterization was performed on one of the synthesized polythiophenes on both undoped and doped (with FeCl₃ or iodine) films. The conductivity and charge‐carrier mobility were assessed by current–voltage and field effect measurements. Well‐structured polymer films were obtained simply via spin coating from chloroform solutions and without the need of further processing, unlike other regioregular polythiophenes reported in the literature. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1758–1770, 2007     

Synthesis of Glucose‐Containing Polyaniline by the Oxidative Polymerization of N‐Glucosylaniline

Summary: The oxidative polymerization of N‐glucosylaniline was carried out using ammonium persulfate as the oxidant in phosphate buffer. The structure of the isolated polymer was determined by ¹H NMR, ¹³C NMR, and UV‐vis spectroscopy to be the polyaniline having glucose residues attached to the general polyaniline unit. Participation of the ortho‐position of the aromatic ring in the polymerization was also confirmed by the analyses.

The oxidative polymerization of N‐glucosylaniline.     

New ferrocene-containing structures: Poly(silyl ester)s

Two new polymeric structures containing ferrocene units along the chains, namely poly(silyl ester)s, have been synthesized and characterized: a geminal poly(silyl ester) (g-PSE) and one having a disiloxane spacer between the silyl ester groups (s-PSE). The condensation polymerization of AA/BB monomer systems in solution was used in both cases as preparation method involving a silicon-containing diol, (diphenylsilane diol or 1,3-bis(hydroxy)-tetramethyldisiloxane), and 1,1′-di(chlorocarbonyl)ferrocene. The polymers were investigated by differential pulse voltammetry in order to evaluate the redox behavior. Due to the presence of the silyl ester groups in the chain, these polymers are hydrolytically degradable.     

Synthesis of arborescent styrene homopolymers and copolymers from epoxidized substrates

The synthesis of arborescent styrenic homopolymers and copolymers was achieved by anionic polymerization and grafting. Styrene and p‐(3‐butenyl)styrene were first copolymerized using sec‐butyllithium in toluene, to generate a linear copolymer with a weight‐average molecular weight M_w = 4000 and M_w/M_n = 1.05. The pendant double bonds of the copolymer were then epoxidized with m‐chloroperbenzoic acid. A comb‐branched (or arborescent generation G0) copolymer was obtained by coupling the epoxidized substrate with living styrene‐p‐(3‐butenyl)styrene copolymer chains with M_w ≈ 5000 in a toluene/tetrahydrofuran mixture. Further cycles of epoxidation and coupling reactions while maintaining M_w ≈ 5000 for the side chains yielded arborescent copolymers of generations G1–G3. A series of arborescent styrene homopolymers was also obtained by grafting M_w ≈ 5000 polystyrene side chains onto the linear and G0–G2 copolymer substrates. Size exclusion chromatography measurements showed that the graft polymers have low polydispersity indices (M_w/M_n = 1.02–1.15) and molecular weights increasing geometrically over successive generations. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012     

Damage and Repair in Informational Poly(N-substituted urethane)s

The degradation and repair of uniform sequence-defined poly(N-substituted urethane)s was studied. Polymers containing an ω-OH end-group and only ethyl carbamate main-chain repeat units rapidly degrade in NaOH solution through an ω→α depolymerization mechanism with no apparent sign of random chain cleavage. The degradation mechanism is not notably affected by the nature of the side-chain N-substituents and took place for all studied sequences. On the other hand, depolymerization is significantly influenced by the molecular structure of the main-chain repeat units. For instance, hexyl carbamate main-chain motifs block unzipping and can therefore be used to control the degradation of specific sequence sections. Interestingly, the partially degraded polymers can also be repaired; for example by using a combination of N,N′-disuccinimidyl carbonate with a secondary amine building-block. Overall, these findings open up interesting new avenues for chain-healing and sequence editing.     

Amphiphilic Hybrid π‐Conjugated Polymers Containing Polyhedral Oligomeric Silsesquioxanes

Amphiphilic hybrid π‐conjugated polymers that have polyhedral oligomeric silsesquioxanes on their side chains have been successfully synthesized by the Sonogashira–Hagihara polycondensation reaction. The obtained polymers were studied with ultraviolet‐visible absorption and photoluminescence spectra. In these polymers, the π‐conjugation length was extended along the poly(p‐phenylene‐ethynylene) backbone. Furthermore, the content of the POSS substituents can influence the aggregation behavior of the polymers and subsequent luminescent properties.

     

Synthesis and characterization of fluorene and cyclopentadithiophene‐based copolymers exhibiting broad absorption for photovoltaic devices

In this study, two low bandgap copolymers composed of fluorene (Fl), cyclopentadithiophene (CDT), and 4,7‐bis(2‐thienyl)‐2,1,3‐benzothiadiazole (DBT) were synthesized, and their optical, electrochemical, and photovoltaic (PV) characteristics were investigated for applications in PV devices. The feed ratio of the Fl and CDT moieties was modulated to tune the electronic structures and resulting optical properties of the polymers. In the copolymeric structures, the Fl‐CDT unit absorbs the short‐wavelength UV/vis regions, and the CDT‐DBT (or Fl‐DBT) unit with strong intramolecular charge transfer characteristics covers the long‐wavelength visible regions. P1 exhibited a wide UV absorption spectrum covering the UV and entire visible region in the range of 300–800 nm, and P2 showed absorption covering from 300 to 700 nm. UV/vis and electrochemical studies confirmed the desirable highest occupied molecular orbital/lowest unoccupied molecular orbital levels of the copolymers with bandgaps of 1.62–1.86 eV, enabling efficient electron transfer and a high open‐circuit voltage when blending them with fullerene derivatives. When the polymers were blended with [6,6]phenyl‐C₆₁‐butyric acid methyl ester, P1 exhibited the best device performance with an open‐circuit voltage of 0.66 V, short‐circuit current of 4.92 mA cm^?2, and power conversion efficiency of 1.13% under Air Mass 1.5 Global (AM 1.5G, 100 mW cm^?2) illumination. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011     

Single step synthesis of poly(3‐octylthiophene)/multi‐walled carbon nanotube composites and their characterizations

The transport properties of conducting polymers are known to be greatly influenced by the chemical unsaturation surrounding the polymer backbone, besides favorable conformation of the side chains present. Polymeric composites with multi‐walled carbon nanotubes (MWNT) can provide a good conductive path at relatively low carbon contents, as these have high aspect ratio, specific surfaces and are cost effective. Hence their use in various applications such as organic LED, solar cells and supercapacitors are very much anticipated. In this respect poly(3‐octylthiophene)/MWNT composites have been prepared by an “insitu” polymerization process in chloroform medium with FeCl₃ oxidant at room temperature. The composites were characterized by Fourier Transfer Infrared spectroscopy (FT‐IR), Raman, work function and X‐ray diffraction (XRD) measurements. The results indicate only a weak π‐π interaction between the moieties, in the absence of a strong covalent bonding. The ultraviolet–visible (UV–Vis) measurements also support this view. The photoluminescence (PL) quenching indicates the effectiveness of the interface in the formation of the donor–acceptor type composite. The conductivity of the composites is followed by a four probe technique to understand the conduction mechanism. The Hall voltage measurement is followed to monitor carrier concentrations and mobilities. The impressive conductivity and mobility values encourage the utility of the composites as photovoltaic material. Copyright © 2008 John Wiley & Sons, Ltd.     

The MX2Lx matrices,with M = Zn2+, Cd2+, Hg2+, X = Cl−, Br−, I− and L = pyrazine,quinoxaline, phenazine

Three structures combining the ditopic organic ligand quinoxaline with divalent metal halides MX₂, with M = Cd²⁺ and Hg²⁺, are reported. All three structures are coordination polymers, with the quinoxaline ligand acting as organic linker between metal centers. In two structures, with M = Hg²⁺ and X = Cl^? or Br^?, the formation of a 1-D, halide-bridged polymer in addition to the quinoxaline coordination polymer increases the dimensionality of the structure to 2-D, while in the case of M = Hg²⁺ and X = Cl^?, the formation of two halide-bridged polymers along with the coordination polymer results in the creation of a 3-D structure. Structural trends are identified, and the templating effect of the organic ligand is highlighted, through horizontal and vertical comparisons of these structures with related structures reported in the literature obtained upon combining the said metal halides with the related organic ligands pyrazine, quinoxaline, and phenazine, presented as the resulting matrices of structures.     

Low temperature heat capacity of heterocyclic polymer networks

The predicted crossover to a fractal-like vibrational regime above 8–10 K was apparently proved by precise measurements of heat capacity of a series of cross-linked heterocyclic polymers.