Epoxide-terminated hyperbranched polyether sulphones (EHBPESs) with different backbone structures were synthesized and used as tougheners for diglycidyl ether of bisphenol-A (DGEBA) curing system, which result in nonphase-separated cured networks. Effects of backbone structure (at comparable degree of polymerization) and loading contents on the mechanical and thermal properties of cured hybrids were investigated. The hybrid containing EHBPES3, which has the most flexible backbone, shows the best mechanical performance and highest glass transition temperature (T_g). Compared with unmodified system, the impact strength, tensile strength, elongation at break of the hybrid containing 5% EHBPES3 increased by 69.8%, 9.4%, and 60.2%, respectively. The balanced improvements were attributed to the increased crosslink density and fractional free volume as well as the unique inhomogeneous network structure because of incorporation of hyperbranched modifiers with proper structure and loading contents. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41910.

Fluorinated siloxane–acrylate polymer latex was synthesized via miniemulsion polymerization, which was carried out by pseudo one-step method. In the synthesis protocol, the monomers of octamethylclotetrasiloxane (D₄), tetravinyltetramethylcyclotetrasiloxane (D₄^v), methyl methylacrylate, butyl acrylate, N-methylol acrylamide, and dodecafluoroheptyl methacrylate (DFMA) were first mixed and homogenized into a miniemulsion, which was stabilized by dedecybenzene sulfonic acid. The ring-opening polymerization of cyclosiloxane was then steadily performed under miniemulsion conditions and followed by the postaddition of radical initiators to initiate the polymerization of acrylate and DFMA monomers. The influences on the emulsion properties by acrylic monomer with different addition protocol were investigated in this work. In addition, the synthesized latexes were characterized by using dynamic laser scattering, transmission electron microscope, differential scanning calorimetry, and Fourier transform infrared spectroscopy. These results indicated that the introduction of D₄^v in the latex can successfully suppress the phase separation between the thermodynamically incompatible components for the formation of uniform hybrid latex particles. The further application of the as-synthesized latex was investigated as a new kind of waterborne textile finishing agent. Moreover, the influences of the content of D₄^v and DFMA on the finishing properties, especially for the softness, the water repellence, and the antimoisture properties, were systematically studied in this work. With a proper design on the content of the D₄^v and DFMA, stable textile finishing emulsion was prepared, which can endow the fabric both desirable softness and excellent water resistances. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40161.

In this report, four donor–acceptor copolymers, P(NDT3-BT), P(NDT3-BO), P(NDF3-BT), and P(NDF3-BO), using 5,10-didodecyl-naphtho[1,2-b:5,6-b′]dithiophene (NDT3) or 5,10-didodecyl-naphtho[1,2-b:5,6-b′]difuran (NDF3) as an electron-rich unit and benzodiathiazole (BT) or benzoxadiazole (BO) as an electron-deficient one, were designed, synthesized, and characterized. Detailed systematical investigation was developed for studying the effect of the S/O atoms on the optical, electrochemical, and morphological properties of the polymers, as well as the subsequent performance of the organic field-effect transistors (OFETs) fabricated from these copolymers. It was found that, compared with NDF3-based P(NDF3-BT)/P(NDF3-BO), by replacing NDF3 with stronger aromatic NDT3, the resultant P(NDT3-BT)/P(NDT3-BO) show smaller lamellar distance with an increased surface roughness in solid state, and relatively higher hole mobilities are obtained. The hole mobilities of the four polymers based on OFETs varied from 0.20 to 0.32 cm² V⁻¹ s⁻¹ depending on their molecular structures, giving some valuable insights for the further design and development of a new generation of semiconducting materials. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 2465–2476

A novel epoxidized hyperbranched poly(phenylene oxide) (EHPPO) is designed and synthesized successfully. The structure of EHPPO is characterized by Fourier transform infrared spectra- and quantitative ¹³C nuclear magnetic resonance spectrum. The synthesized EHPPO is added into diglycidyl ether of bisphenol A as a modifier in different ratios to form hybrids and cured by an anhydride curing agent. Effects of EHPPO addition on the properties of the cured hybrids are investigated. Thermal mechanical analysis results suggest that addition of EHPPO can increase the free volume of the cured hybrid materials. Dynamic mechanical analysis characterizations show that the crosslinking density increases with the increase in EHPPO content. Furthermore, addition of EHPPO results in an improvement in thermal and mechanical properties. The toughening mechanism is also discussed. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

A new epoxy-ended hyperbranched polyether (HBPEE) with aromatic skeletons was synthesized through one-step proton transfer polymerization. The structure of HBPEE was confirmed by Fourier transform infrared spectroscopy (FTIR), and nuclear magnetic resonance (NMR) measurements. It was proved to be one high efficient modifier in toughening and reinforcing epoxy matrix. In particular, unlike most other hyperbranched modifiers, the glass transition temperature (T_g) was also increased. Compared with the neat DGEBA, the hybrid curing systems showed excellent balanced mechanical properties at 5 wt % HBPEE loading. The great improvements were attributed to the increased cross-linking density, rigid skeletons, and the molecule-scale cavities brought by the reactive HBPEE, which were confirmed by dynamical mechanical analysis (DMA) and thermal mechanical analysis (TMA). Furthermore, because of the reactivity of HBPEE, the hybrids inclined to form a homogenous system after the curing. DMA and scanning electron microscopy (SEM) results revealed that no phase separation occurred in the DGEBA/HBPEE hybrids after the introduction of reactive HBPEE. SEM also confirmed that the addition of HBPEE could enhance the toughness of epoxy materials as evident from fibril formation. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1064-1073, 2013

Diglycidyl ether of bisphenol A (DGEBA)/fluoro-terminated hyperbranched poly(phenylene oxide) (FHPPO) composites with improved mechanical and dielectric performances were prepared by blending a FHPPO with DGEBA. The low-polarity building blocks, abundant fluorinated terminal groups, and the inherent free volume brought by FHPPO efficiently lowered the dielectric constant and the dissipation factor. The free volumes of the cured DGEBA/FHPPO composites, which were quantified by positron annihilation lifetime spectroscopy, increased with the FHPPO loading. The moisture absorption of composites also decreased after the introduction of FHPPO due to the hydrophobicity of fluorinated substituents. Dynamic mechanical analysis tests and scanning electron morphology revealed that FHPPO phase separated from the composites during the curing process. The average diameter of dispersed FHPPO particles increased proportionally with the FHPPO loading. Composites with dispersed particle size of around 150 nm showed the best comprehensive mechanical performance. In addition, incorporation of FHPPO, which has lots of aromatic structures, into DGEBA also increased the thermal stabilities. POLYM. COMPOS., 34:1051–1060, 2013. © 2013 Society of Plastics Engineers

A series of novel poly(thienylene vinylene) derivatives (PTVs), P20-P24, with imide substituents were designed and synthesized by palladium-catalyzed Stille coupling polymerization, wherein the imide substituent density was decreased gradually, which allowed us to explicitly study the effect of electron-deficient substituent on the optical, electrochemical, and photovoltaic properties of the PTVs. All of the four polymers showed broad absorption bands with optical bandgaps between1.66 and 1.78 eV. By reducing density of electron-deficient imide group, the LUMO energy levels of the polymers could be tuned gradually from −3.75 to −3.43 eV, with HOMO levels upshifted from −5.64 to −5.16 eV. Bulk heterojunction solar cells with the polymers as donor and PC₇₁BM as acceptor demonstrated very different excitons dissociation behavior. With decreasing the imide-fused unit density, the open-circuit voltage (V_OC) values in the devices decreased from 0.78 to 0.62 V, whereas the short-circuit currents (J_SC) increased from 0 to 2.26 mA cm⁻² and then decreased to 1.01 mA cm⁻². By adjusting the electron-withdrawing imide substituent density, power conversion efficiency of the PTVs-based solar cells can be increased to four times, reached 0.86%. To the best of our knowledge, this is the first systematic study of the relationship between molecular energy level and photovoltaic properties of PTVs. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 4975–4982

Two novel porphyrin-based D-A conjugated copolymers, PFTTQP and PBDTTTQP, consisting of accepting quinoxalino[2,3-b′]porphyrin unit and donating fluorene or benzo[1,2-b:4,5-b′]dithiophene unit, were synthesized, respectively via a Pd-catalyzed Stille-coupling method. The quinoxalino[2,3-b′]porphyrin, an edge-fused porphyrin monomer, was used as a building block of D-A copolymers, rather than the simple porphyrin unit in conventional porphyrin-based photovoltaic polymers reported in literature, to enhance the coplanarity and to extend the π-conjugated system of polymer main chains, and consequently to facilitate the intramolecular charge transfer (ICT). The thermal stability, optical, and electrochemical properties as well as the photovoltaic characteristics of the two polymers were systematically investigated. Both the polymers showed high hole mobility, reaching 4.3 × 10⁻⁴ cm² V⁻¹ s⁻¹ for PFTTQP and 2.0 × 10⁻⁴ cm² V⁻¹ s⁻¹ for PBDTTTQP. Polymer solar cells (PSCs) made from PFTTQP and PBDTTTQP demonstrated power conversion efficiencies (PCEs) of 2.39% and 1.53%, both of which are among the highest PCE values in the PSCs based on porphyrin-based conjugated polymers. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013

A novel fused ladder alternating D–A copolymer, PIDT–DPP, with alkyl substituted indacenodithiophene (IDT) as donor unit and diketopyrrolopyrrole (DPP) as acceptor unit, was designed and synthesized by Pd-catalyzed Stille-coupling method. The copolymer showed good solubility and film-forming ability combining with good thermal stability. PIDT–DPP exhibited a broad absorption band from 350 to 900 nm with an absorption peak centered at 735 nm. The optical band gap determined from the onset of absorption of the polymer film was 1.37 eV. The highest occupied molecular orbital level of the polymer is as deep as −5.32 eV. The solution-processed organic field-effect transistor (OFETs) was fabricated with bottom gate/top contact geometry. The highest FET hole mobility of PIDT–DPP reached 0.065 cm² V⁻¹ s⁻¹ with an on/off ratio of 4.6 × 10⁵. This mobility is one of the highest values for narrow band gap conjugated polymers. The power conversion efficiency of the polymer solar cell based on the polymer as donor was 1.76% with a high open circuit voltage of 0.88 V. To the best of our knowledge, this is the first report on the photovoltaic properties of alkyl substituted IDT-based polymers. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012

A light-emitting partially conjugated hyperbranched polymer (2,5-dimethoxy-substituted hyperbranched poly(p-phenylene vinylene), MOHPV) based on rigid fluorescent conjugated segments, 2,5-dimethoxy-substituted distyrylbenzene (a derivative of oligo-poly(p-phenylene vinylene)), and flexible non-conjugated spacers, trioxymethylpropane, was synthesized via an A₂ + B₃ approach. The weight-average molecular weight was 2.48 × 10⁴ g mol⁻¹. The introduction of two methoxy groups into central rings of the oligo-poly(p-phenylene vinylene) imparted to MOHPV better solubility in common organic solvents and processability than its analogues reported in our previous work, especially the fully conjugated hyperbranched polymers. The effect of the molar ratio of monomer A₂ to monomer B₃ on the molecular weight and molecular weight distribution was investigated. A single-layer light-emitting diode was fabricated employing MOHPV as an emitter. A double-layer light-emitting diode was also fabricated by doping an electron transport material, 2-(4-biphenylyl)-5-phenyl-1,3,4-oxadiazole, into the emitting layer and inserting a thin layer of tri(8-hydroxyquinoline)aluminium as electron-transporting/hole-blocking layer. A maximum luminance of 1500 cd m⁻² at 12 V and a maximum electroluminescence efficiency of 1.38 cd A⁻¹ at 14 mA cm⁻³, which are approximately 43.5 and 12.9 times greater, respectively, than those of the single-layer device, were achieved. The synthetic simplicity, excellent solubility and solution processability, and less of a propensity to aggregation make MOHPV a novel type of emitter for polymer light-emitting displays. Copyright © 2010 Society of Chemical Industry

To simplify the preparation of unsaturated polymers, a new type of divinyl monomer was designed in this article. The double bonds of the divinyl monomer are different not only in reactivity but also in electron density. Based on quantum chemistry calculation, (z)-4-(2-(acryloyloxy)ethoxy)-4-oxobut-2-enoic acid (cis-AEOEA) was selected as the nonelectron-donating divinyl monomer in which inactive double bond was electron deficient and can be activated by electron-donating comonomers by forming charge transfer complex (CTC) copolymerization system. So, cis-AEOEA can be used to simplify the preparation of unsaturated polymers and the content of inactive double bonds left in the polymer is controlled by electron-donating ability of comonomers. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

In this article, electrochemical behaviors and their topography observation for four organic coatings used in seawater, by using both electrochemical impedance spectroscopy (EIS) and atomic force microscopy (AFM) methods to study environment behaviors of different coatings as well as the effects of their film formation, pigments, and fillers on anticorrosion behaviors, were measured. The results show that polyurethane, epoxy, and chlorinated rubber coatings all present one capacitive loop in their tested EIS which contains phenomenally only one time constant, whereas alkyd coating presents two capacitive semicircle arcs. With two capacitive loops, the capacitive semicircle in the high frequency range represents barrier layer property, but the semicircle in the low frequency range represents corrosion reaction of metals under the film. Polyurethane coating used in seawater has well anticorrosion property in seawater immersion test. The appearance features of different layers are visible different between different layers of tested coatings at their surface topography. The property of polyurethane paint film coated on metal is better than other layers, and film of alkyd coating has many pits at its surface by observing the layer's images. AFM photos imaged have also been used to further detail surface topography for four organic coatings, and to approve effects of topography of these coatings on its electrochemical behaviors, from two views of both height and phase modes. It is beneficial to explain deeply the environment behaviors and degradation mechanism of organic coatings. To further study failure of these organic coatings and dynamic processes of corrosion of metal under the film, two equivalent circuit models, according to these tested EIS, have been suggested to explain the corrosive kinetics of these four coatings. To polyurethane, epoxy, and chlorinated rubber coatings used in seawater which have good protection effects for substrate metal, the diffusion process for water, from their layer's surface to interface of film/metal, is mainly controlled factor for degradation. However, the electrochemical reaction process has may become a control procedure for corrosion of alkyd coated metal. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008