Author Archive

Editorial Board’s Top Picks: Emily Pentzer

Emily Pentzer is an Associate Editor for Polymer Chemistry and an Assistant Professor of Chemistry at Case Western Reserve University, USA. Her research addresses application-based materials problems in the areas of energy harvesting, management, and storage. She uses synthetic chemistry to tailor molecular design and control self-assembly for the preparation and study of novel conductive materials with controlled domain sizes and interfaces.

You can find all Editorial Board’s Top Picks papers in our web collection.



Focus on PAH building blocks for electronically active and porous polymers (Associate Editor: Prof Emily Pentzer Case Western Reserve University, USA)

Polyaromatic hydrocarbons (PAHs) are attractive building blocks for electronically active and porous organic polymers. For these applications, the preparation and isolation of appropriate polymeric structures is needed to provide the desired properties. PAHs are typically incorporated into conjugated polymers by transition metal-catalyzed cross-coupling reactions, and their solubility and solution processability is ensured by substitution with alkyl groups; recent interest has focused on accessing reduced band gap structures.  Alternatively, for the preparation of porous organic polymers, the tendency of PAHs to aggregate through p-p interactions must be overcome, and alkyl groups are disadvantageous for gas adsorption/storage.  Recent advances in the design and synthesis of PAH-containing polymers have helped expand the usefulness of these heteroatom-free systems.

1. Anthanthrene as a large PAH building block for the synthesis of conjugated polymers
Antoine Lafleur-Lambert, Jean-Benoît Giguère and Jean-Francois Morin
Polym. Chem., 2015, 6, 4859-4863

Aromatic anthanthrene is readily available from the common dye vat orange 3 and can be used to prepare PAH-containing polymers.  Morin and coworkers report the preparation of a series of anthanthrene-based conjugated polymers. The anthanthrene unit has branched alkyl substituents to control solubility and was copolymerized with electron rich and electron poor aryl comonomers. The absorption spectra of these polymers range from 450 to 850 nm, depending on the constituent materials. The series of novel polymers all showed similar LUMO levels, and variation of the HOMO levels show no trends based on the comonomer identity. These results indicate that both the HOMO and the LUMO orbitals are located on the anthanthrene units, and are not heavily influenced by the comonomer identity.

2. Dicyclopenta[cd,jk]pyrene based acceptors in conjugated polymers
Sambasiva R. Bheemireddy and Kyle N. Plunkett
Polym. Chem., 2016, Advance Article

In this study, Plunkett and Bheemireddy report the use of the PAH dicyclopentapyrene, as an acceptor unit in conjugated polymers. This alkylated monomer was copolymerized with various electron donor comonomers including thiophene, bithiophene, and diethynyl benzene. In the thin film, these polymers show broad absorption profiles, from ~320-720 nm, corresponding to band gaps of ~1.7 eV. The identity of the comonomer with the PAH had little influence on the HOMO and LUMO levels, inconsistent with traditional donor-acceptor theory for reduced bandgap materials.  In fact, DFT calculations show the LUMO orbital distribution across the series is essentially unchanged and mostly located on the PAH unit (as expected), but surprisingly, the HOMO orbitals are also localized to the PAH unit for the thiophene and bithiophene polymers.

3. Di(naphthalen-2-yl)-1,2-diphenylethene-based conjugated polymers: aggregation-enhanced emission and explosive detection
Mengxia Gao, Yue Wu, Bin Chen, Bairong He, Han Nie, Tingyan Li, Fupeng Wu, Wenjun Zhou, Jian Zhou and Zujin Zhao
Polym. Chem., 2015, 6, 7641-7645

Di(naphthalene-2-yl)-1,2-diphenylethene is used as a building block by Zhao and coworkers to prepare fluorescent conjugated polymers which show aggregation induced emission. Addition of the poor solvent water to these polymers in THF causes them to aggregate and essentially turns on the fluorescence of the materials by preventing non-radiative excited state decay. DFT calculations show the HOMO and LUMO orbitals are significantly distributed over both comonomers, as well as the pendant naphthyl groups, indicating good intramolecular orbital overlap. These materials further show potential to detect explosives under aqueous conditions, as the fluorescence is quenched in the presence of picric acid.

4. Facile approach for preparing porous organic polymers through Bergman cyclization
Xian-Mei Zhang, Xuesong Ding, Aiguo Hu and Bao-Hang Han
Polym. Chem., 2015, 6, 4734-4741

The Bergman cyclization reaction was used to prepare microporous polymers from a triphenylene-based monomer that contains three ene-diyne moieties. This catalyst-free and thermally induced intramolecular cyclization produces three 1,4-benzene biradical per monomer that undergo intermolecular coupling to yield the porous polymer. Although the monomers themselves are planar, they link together in a non-planar fashion to give a porous, high surface area material. Han and coworkers then demonstrate that the novel micorporous polymers show high adsorption capacity for both hydrogen and carbon dioxide.

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Editorial Board’s Top Picks: Bin Liu

Bin Liu is an Associate Editor for Polymer Chemistry and Dean’s Chair Professor at the Department of Chemical & Biomolecular Engineering, National University of Singapore (NUS), Singapore. Her research focuses on the development of organic functional materials and the exploration of their applications in sensing, imaging and solar cells.

You can find all Editorial Board’s Top Picks papers in our web collection



Focus on Responsive Polymers (Associate Editor: Prof Bin Liu, NUS, Singapore)

1. Voltage-responsive micelles based on the assembly of two biocompatible homopolymers
Liao Peng, Anchao Feng, Huijuan Zhang, Hong Wang, Chunmei Jian, Bowen Liu, Weiping Gao and Jinying Yuan. Polym. Chem. 2014, 5, 1751-1759.

Effective drug delivery and drug release systems in vivo generally require drug carriers to specifically respond to external stimuli. J. Yuan and coworkers from Tsinghua University (China) have synthesized voltage-responsive biocompatible micelles based on two host and guest molecules, poly(ethylene glycol) homopolymer modified with beta-CD (PEG-beta-CD) and the poly(L-lactide) homopolymer modified with Fc (PLLA-Fc). A reversible assembly- disassembly transition of this micellar system was realized through electrochemical control and voltage-controlled drug release was also successfully demonstrated.

2. Reversibly crosslinked thermo- and redox-responsive nanogels for controlled drug release
Ji Liu, Christophe Detrembleur, Marie Hurtgen, Antoine Debuigne, Marie-Claire De Pauw-Gillet, Stéphane Mornet, Etienne Duguet and Christine Jérôme. Polym. Chem. 2014, 5, 77-88.

Micelle assembly using crosslinking could minimize the premature drug delivery usually observed in physically assembled micelles. C. Detrembleur, C. Jérôme and coworkers from the University of Liege (Belgium) have prepared reversibly crosslinked poly(vinyl alcohol)-b-poly(N-vinylcaprolactam) PVOH-b-PNVCL nanogel by using a redox-responsive crosslinking agent, and demonstrate its effectiveness in thermo- and redox responsive drug delivery using Nile red (NR) as a hydrophobic drug model.

3. Light-responsive linear-dendritic amphiphilles and their nanomedicines for NIR-triggered drug release
Lin Sun, Bangshang Zhu, Yue Su and Chang-Ming Dong. Polym. Chem. 2014, 5, 1605-1613.

Development of new-generation polymeric nanomedicines with spatiotemporal and/or on-demand drug-release behaviour is in high demand for clinical therapies and personalized medicines. Taking advantage of the stealthy properties of biocompatible PEO and the multivalent periphery properties of dendritic polymers, C. M. Dong and coworkers at Shanghai Jiao Tong University in China, have reported the synthesis of both ultraviolet (UV) and near-infrared (NIR) light-responsive linear-dendritic amphiphiles, which have been successfully used for light-triggered drug release.

Review article

1. Multi-stimuli responsive polymers – the all-in-one talents
Philipp Schattling, Florian D. Jochum and Patrick Theato. Polym. Chem. 2014, 5, 25-36.

The manifold applications of in stimuli-responsive polymers have spurred increasing research interest in the field.  The combination of multiple responsive groups into one polymer may produce a multi-functional polymer which exhibits a multifaceted change of material properties when applying one or more external stimuli.  In this review article, P. Theato et. al. at University Hamburg in Germany, summarised recent developments in the area of multi-stimuli responsive polymers with more than two responsive groups and highlighted a number of fascinating examples. These multi-responsive materials will open up opportunities for development of both life science and information technology.

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Photopolymerization Fundamentals Conference 2015

Congratulations to Brian Donovan, a PhD student in the Patton Group at the University of Southern Mississippi, USA, who was awarded the Polymer Chemistry Best Poster Award at the Photopolymerization Fundamentals Conference 2015 in Boulder, Colorado, USA. Brian received the award from Polymer Chemistry Associate Editor, Professor Christopher Barner-Kowollik, in the presence of the conference chair, Professor Christopher Bowman, for his work on the effects of phosphonic acid monomers on the network properties of UV polymerizable adhesives.

Pictured (left to right): Professor Christopher Bowman, Brian Donovan and Professor Christopher Barner-Kowollik.
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