Synthesis and properties of oxetane monomers and oligomers with electro‐active pendent groups

BACKGROUND: Monomers and polymers carrying pendent electro‐active fragments are widely studied due to their application in various optoelectronic devices. Monomers containing triphenylamino, triphenyldiamino and carbazol‐9‐yl fragments with vinyl, epoxy or acryl functional groups are mostly used. The synthesized materials are used for preparation of hole transport layers as well as host materials for electrophosphorescent light‐emitting diodes. Much fewer presentations are reported on the preparation of monomers containing other electro‐active or functional groups. RESULTS: Here we describe oxetane monomers and their oligomers containing various electro‐active pendent groups. The weight‐average molecular weights of the oligomers are in the range 1420–3250 g mol^?1 with a molecular weight distribution of 1.7–4.1. The electron photoemission spectra of amorphous layers of the compounds established ionization potentials of 5.55–5.85 eV. Room temperature hole drift mobility in the layers of some oligomers exceeds 10^?7 cm² V^?1 s^?1 at high electric fields. CONCLUSION: The synthesized oligomers exhibit promising thermal and film‐forming properties. Amorphous layers of some of the materials demonstrate suitable ionization potentials and sufficient hole transport properties for their application in optoelectronic devices. Copyright © 2008 Society of Chemical Industry     

Optimal design of an imprinted preassembled system by quantum chemical calculations and preparation of a surface‐imprinted material for the selective removal of quinoline

In this study, we examined the rational preparation of molecularly imprinted polymers (MIPs) for the selective removal of quinoline from octane. Before the preparation, density functional theory, as one of the methods of quantum chemical calculation, was used for the simulation of a quinoline‐imprinted preassembly system. Methacrylic acid turned out to be the more suitable monomer for quinoline compared with acrylamide, and different template–monomer ratios, including 1:1, 1:2, and 1:3, were studied and are discussed. On the basis of the result of molecular simulation, quinoline‐imprinted polymers were prepared with a combination of surface imprinting and living polymerization. The prepared quinoline–MIPs were characterized and used as selective adsorbents for batch‐mode binding experiments. The fitting result of the adsorption data indicates that the adsorption kinetics and adsorption isotherms of the quinoline‐imprinted polymers fit well a pseudo‐second‐order kinetics model and the Freundlich model, respectively. A selective recognition ability was demonstrated by equilibrium binding analysis. This study will provide needful guidance and a theoretical basis for the preparation of imprinted materials in the field of industrial denitrification. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41730.     

Syntheses and the Main Properties of Fiban Fibrous Ion Exchangers

The works on synthesis and main properties of fibrous ion exchangers are reviewed in the paper. The main attention is paid to the FIBAN materials found practical applications in water treatment and air purification processes. The following methods for preparation of ion exchange fibers have been considered: mechanical mixing of inert fiber‐forming polymer solutions or melts with finely dispersed ion‐exchangers with their following spinning into fibers; preparation of composite fibers containing polymeric reinforcement in the polyelectrolyte body; spinning of specially prepared polymers containing ionizable groups and having fiber‐forming properties; grafting of ionogenic polymers (or polymers in which ionogenic groups can be introduced after grafting) onto polymer chains of the existing polymer fiber; polymer analogues conversion of existing polymeric fibers by introducing in their structure ionizable functional groups. Conditions for preparation of ion exchange fibers with high exchange capacity, optimal swelling and acceptable mechanical properties have been outlined.     

Conjugated polymers with tethered electron‐accepting moieties as ambipolar materials for photovoltaics

Conjugated polymers are of increasing interest as semiconductors for soft (opto)electronic devices, including photovoltaic elements. A promising conversion of solar energy into electrical energy is possible with blends of soluble electron donor‐type conjugated polymers and fullerenes as electron‐acceptor, transporting component. This approach, called bulk‐heterojunction, suggested the preparation of intrinsic ambipolar materials to control simultaneously the electronic and morphological properties. On these bases, the covalent grafting of acceptor moieties onto conjugated backbones seemed attractive for the preparation of intrinsically ambipolar polymeric materials (‘double‐cable’ polymers) as an alternative to donor–acceptor composites. The design, characterisation and application of this novel class of polymers are reviewed taking into account the current understanding of organic photovoltaics. Copyright © 2007 Society of Chemical Industry     

Nanofibrous nonwovens based on dendritic‐linear‐dendritic poly(ethylene glycol) hybrids

Dendritic‐linear‐dendritic (DLD) hybrids are highly functional materials combining the properties of linear and dendritic polymers. Attempts to electrospin DLD polymers composed of hyperbranched dendritic blocks of 2,2‐bis(hydroxymethyl) propionic acid on a linear poly(ethylene glycol) core proved unsuccessful. Nevertheless, when these DLD hybrids were blended with an array of different biodegradable polymers as entanglement enhancers, nanofibrous nonwovens were successfully prepared by electrospinning. The pseudogeneration degree of the DLDs, the nature of the co‐electrospun polymer and the solvent systems used for the preparation of the electrospinning solutions exerted a significant effect on the diameter and morphology of the electrospun fibers. It is worth‐noting that aqueous solutions of the DLD polymers and only 1% (w/v) poly(ethylene oxide) resulted in the production of smoother and thinner nanofibers. Such dendritic nanofibrous scaffolds can be promising materials for biomedical applications due to their biocompatibility, biodegradability, multifunctionality, and advanced structural architecture. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45949.     

Conjugated polymers with regularly spaced m‐phenylene units and post‐polymerization modification to yield stimuli‐responsive materials

Two π‐conjugated polymers featuring main‐chain m‐phenylene linkers as well as iodo substituents were initially prepared. The presence of the iodo functionality allowed for the preparation of six additional polymers from the initial two iodo‐substituted polymers via facile post‐polymerization modification using Sonogashira‐type coupling chemistry. The post‐polymerization modification led to crosslinking, to the incorporation of a pyridyl‐bearing functionality for potential use as a ligand for transition metals or to the introduction of a ferrocenyl substituent as a possible redox‐active unit. The m‐phenylene units were incorporated into the polymer main‐chain structure in order to periodically disrupt conjugation, thereby allowing for more uniformity in the effective conjugation length and thus in absorption and emission profiles. The thermal stability and photophysical properties of all eight polymers, as well as the stimuli‐responsiveness of relevant materials to nitroaromatics and metal ions, are reported. © 2015 Society of Chemical Industry     

Soybean oil‐based shape‐memory polyurethanes: Synthesis and characterization

Shape‐memory polymers (SMPs) have wide range of applications due to their ability to sense environmental stimuli and reshape from a temporary shape to a permanent shape. Plant oil‐based polymeric materials are highly concerned in recent years in consideration of petroleum depletion and environmental pollution. However, plant oil‐based polymers are rarely investigated regarding their shape‐memory characteristics though bio‐based SMPs are highly desired nowadays. In this study, a series of soybean oil‐based shape‐memory polyurethanes (SSMPUs) are prepared through a mild chemo‐enzymatic synthetic route, and their properties are fully characterized with tensile testing, DSC, dynamic mechanical analysis (DMA), and shape‐memory testing. Results show that SSMPUs are soft rubbers with tensile strength in the range of 1.9–2.2 MPa and glass transition temperature in the range of 2–5°C, and possess good shape recoveries at RT when stretching ratio is 10, 20, and 30%, respectively. This work would promote the development of high‐value‐added plant oil‐based shape‐memory polyurethanes. Practical applications: Using annual renewable plant oil as feedstock, the synthesized SSMPUs show good shape recovery properties, which will make them applicable as potential alternatives to petroleum‐based shape‐memory materials. The simple and mild preparation process also contributes to the further exploration of plant oil to value‐added functional materials.     

Polymers and nanocomposites: synthesis and metal ion pollutant uptake

This paper is an overview of the versatile polymer materials containing different functional groups at the main or side chain to remove hazardous inorganic species. These materials include water‐insoluble, nanocomposite and water‐soluble polymers. Water‐insoluble polymers and nanocomposites are used in adsorption and ion exchange processes, whereas water‐soluble polymers are employed with ultrafiltration membranes in the liquid‐phase polymer‐based retention technique. © 2015 Society of Chemical Industry     

Modifying and managing the surface properties of polymers

An ongoing challenge in polymer science is the preparation of materials with bespoke surface properties which differ from that of the bulk, for example hydrophobicity, wettability, chemical resistance, adhesion or biocompatibility. We highlight here recent efforts in the design, development and application of (multi)end‐functionalized polymers as additives for the efficient modification of polymer surface properties. Aryl‐ether moieties bearing up to eight functional groups have been used as initiators for the controlled polymerization of both styrene and methyl methacrylate by atom transfer radical polymerization (ATRP) and of lactide by ring opening polymerization (ROP). The resulting polymers have been used as additives to modify the surfaces of the corresponding bulk polymers. Fluorinated polymer surfaces are particularly appealing in terms of their liquid repellence, chemical inertness and low coefficient of friction. When an additive consisting of a low molecular weight polystyrene chain, end‐capped with four C₈F₁₇ groups, is present in a matrix of polystyrene at levels as low as 0.1%, near polytetrafluoroethylene‐like surface properties result. Copyright © 2007 Society of Chemical Industry     

Recent advances in photorefractive and photoactive polymers for holographic applications

The current state‐of‐the‐art of photorefractive and photoactive polymers for holographic applications is summarized and reviewed. Photorefractive polymers and some kinds of photoactive materials based on the azobenzene chromophore have great potential for updatable holographic applications. Updatable three‐dimensional holographic displays of large size have been developed using photorefractive polymers as well as photoactive azobenzene materials. Time responses of photorefractive polymers of the order of seconds and hundreds of milliseconds are currently improved to be of the order of milliseconds to hundreds of microseconds with high diffraction efficiency and high optical gain. © 2016 Society of Chemical Industry     

锂离子电池聚合物正极材料研究进展

高储能的锂电池聚合物正极材料是近年来新型电化学能源研究发展的热点。本文综述了自由基聚合物、导电聚合物、有机多硫聚合物以及多骨架碳硫交联聚合物正极材料的结构、制备、导电机理和电化学性能。重点介绍了自由基聚合物氮氧结构的特点和快速充放电性能,导电聚合物的合成方法和掺杂机理,以及有机多硫聚合物和多骨架碳硫交联聚合物中—(S—S)n—键的高效储能特性和超高比容量性质。最后提出了解决聚合物材料容量的衰减和易降解性以保证稳定的循环性能以及完善合成及制备工艺是未来的研究重点。     

Hydroxyl‐functional polyurethanes and polyesters: synthesis,properties and potential biomedical application

This mini review gives an overview of the synthesis of polyurethanes and polyesters with pendant hydroxyl groups performed mainly in our group. Significant for the synthesis of most of these polymers with hydroxyl‐functional side groups is that no protection groups are needed. This is realised either by generating the OH group during polymer synthesis—demonstrated by the preparation of hydroxyl‐functional polyurethanes from dicarbonate monomers and diamines—or by using catalysts which discriminate between primary and secondary OH groups—demonstrated by the synthesis of hydroxyl‐functional polyesters based on malic acid using scandium triflate as catalyst. In addition, the potential of carbonate couplers for the synthesis of multifunctional polyurethane is presented. The application of such multifunctional polyurethanes as antimicrobial polymers and coatings is briefly discussed. Copyright © 2012 Society of Chemical Industry     

聚合物材料的微波制备技术

介绍了微波对聚合物材料的作用原理和影响因素,综述了微波技术在聚合物微球、热固性聚合物、功能性聚合物和聚合物泡沫材料制备方面的应用。指出微波技术具有选择性加热的特性,将在功能性高分子复合材料的制备方面具有独特的优势。     

Synthesis of highly efficient D‐naproxen imprinted polymer and investigation of their specific performance

D‐naproxen was selected as the imprinted molecule. An original ultraviolet spectrum analysis method based on proof of solvent effects was designed to verify the realization of the noncovalent self‐assembly between naproxen and functional monomers under the influence of the solvents with different nature. The facts proved that it is a more scientific way to effectively implement the pre‐selection of functional monomer. Then, a series of molecular imprinted polymers (MIPs) were synthesized by different ratios of raw materials. These products were detected by infrared spectroscopy as well as adsorption experimentation to analyze their structure and performance. Meanwhile, the transmission electron microscopy (TEM) was first used to observe the morphology of MIPs, by which the pore‐forming mechanism and the effect of the solvent (porogen) were investigated. The MIPs with morphology of different structure were also tested in the adsorption kinetics experiments to testify the influence of morphology factors on the materials' adsorption properties. Through the evaluation of the imprinting efficiency, the best condition accessing to the preparation of highly efficient D‐naproxen imprinted polymer was obtained. The apparent imprinting efficiency of the ultimate product was as high as 90.39%. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Spray‐dried microspheres as a route to clay/polymer nanocomposites

A new strategy for the preparation of well‐dispersed clays in a polymer matrix by a spray‐drying method is presented. Scanning electron microscopy and transmission electron microscopy measurements show that the spray‐drying process produces clay/polymer microspheres in which the clay is trapped in a well‐dispersed state throughout the polymer matrix. The microspheres have been successfully extruded into clay/poly(methyl methacrylate) nanocomposite bulk structures without any perturbation of the well‐dispersed clay nanostructure in the original microspheres. Transmission electron microscopy and small‐angle X‐ray scattering show that the clay particles in the extruded materials range from single platelets to simple tactoids composed of a few stacked clay platelets, indicating an excellent degree of dispersion. The results show that sprayed microspheres are very good precursors for further processing such as extrusion or melt blending with other polymers for bulk nanocomposite fabrication. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Transforming polymer blends into composites: a pathway towards nanostructured materials

Polymer blends and polymer‐based composites are two of the most rapidly developing groups of materials being of industrial, as well as of academic, interest. More than a decade ago a new group of polymer materials was introduced, which became known under the name ‘microfibrilar composites’ (MFCs). They were obtained by the transformation of blends of thermoplastic polymers into micro‐ or nanostructured systems by combination of appropriate mechanical and thermal treatments. Since then, the importance of these novel materials, both for theory and for engineering practice, has increased significantly. It is an objective of this review to outline the place of MFCs within the whole variety of polymer‐based composites. Furthermore, the methods of their preparation, the ways of investigating their structure and the relation of the structure and mechanical properties are discussed. Ultimately, an evaluation of the future trends in this exiting interdisciplinary research field is attempted. Copyright © 2007 Society of Chemical Industry     

新型功能化高吸水性树脂的研究进展

高吸水性树脂是一类新型的功能高分子材料,因其特殊的性能而广泛应用于石油化工、医疗卫生、建筑工程、农林业生产等众多领域.综述了高吸水性树脂的合成方法、应用领域以及发展趋势,并提出了性能改进的方法.     

Material Advancements in Fabrication of Mixed‐Matrix Membranes

The mixed‐matrix membrane (MMM) is a new membrane material for gas separation and plays a vital role for the advancement of current membrane‐based separation technology. Blending between inorganic fillers like carbon molecular sieves, zeolite, metal oxides, silica and silica nanoparticles, carbon nanotubes, zeolitic imidazolate framework, metal organic framework, and glassy and rubbery polymers etc. is possible. Due to mechanical, thermal, and chemical stability, these membranes achieve high permeability and selectivity as compared to pure polymeric materials. Despite of these advantages, the MMM performances are still below industrial expectations because of membrane defects and related processing problems as well as the nonuniform dispersion of fillers in MMMs. Material selection for organic and inorganic phases, preparation techniques, material advancements, and performance of MMMs are discussed. Issues and challenges faced during MMM synthesis as well as problem solutions are highlighted.     

Controlled radical copolymerization of multivinyl crosslinkers: a robust route to functional branched macromolecules

Controlled radical polymerization (CRP) has both revolutionized the synthesis of linear polymers and enabled unprecedented topological complexity. While the synthesis of many polymeric architectures requires careful planning and specialized precursors, branched macromolecules such as segmented hyperbranched polymers (SHPs), knotted polymers, core‐crosslinked stars (CCSs), and more can be synthesized through the copolymerization of vinyl monomers and divinyl crosslinkers in only a few steps. In the nearly two decades since its discovery, this strategy has helped elucidate the fundamental polymerization behavior of crosslinkers and also yielded a variety of functional and stimuli‐responsive materials. The purpose of this mini‐review is to therefore overview critical fundamental aspects of CRP of crosslinkers and materials derived therefrom. The process by which both SHPs and CCS polymers are synthesized, the effect of key reaction parameters and intriguing recent advances are described with the intent of both educating new researchers and inspiring new directions in this area. © 2020 Society of Industrial Chemistry     

一类崭新的聚合型色素的合成与应用

聚合型色素由于分子中带有可聚合基团,可通过与高分子单体的共聚反应将发色母体以高浓度结合于聚合物分子主链或侧链上,从而具有优异的耐迁移性、耐溶剂性、与高分子材料的良好相容性以及较高的生理安全性等,并已被成功地开发应用于合成材料着色和功能材料等领域。本文综述了这一类色素的合成及应用。