Paper of the week: Nanoscale detection of metal-labeled copolymers in patchy polymersomes

Ruiz-Pérez et al. report the nanoscale detection of metal-labelled copolymers in patchy polymersomes.

The synthesis of polymersome-forming block copolymers using two different synthetic routes based on Atom Transfer Radical Polymerisation (ATRP) and Reversible Addition Fragmentation chain Transfer (RAFT) polymerisation is reported. Functionalisation with 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) allowed the block copolymer chains to be labelled with electron-dense metal ions (e.g. indium). The resulting metal-conjugated copolymers can be visualised by transmission electron microscopy with single chain resolution, hence enabling the study of polymer/polymer immiscibility and phase separation on the nano-scale.

Nanoscale detection of metal-labeled copolymers in patchy polymersomes by Lorena Ruiz-Pérez, Jeppe Madsen, Efrosyni Themistou, Jens Gaitzsch, Léa Messager, Steven P. Armes and Giuseppe Battaglia, Polym. Chem., 2015, 6, 2065-2068.

Remzi Becer is a web-writer and Advisory Board member for Polymer Chemistry. He is currently a Senior Lecturer in Materials Science and the director of the Polymer Science and Nanotechnology masters programme at Queen Mary, University of London. Visit www.becergroup.com for more information.

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Author of the Month: Dr. Antoine Debuigne

Dr. Antoine Debuigne is currently a Research Associate of the National Fund for Scientific Research (F.R.S. – FNRS) at the University of Liege, Belgium. He graduated in 1999 from the University of Namur, Belgium, following a master’s thesis in organic chemistry. In 2004, he obtained his Ph.D. degree from the Center for Education and Research on Macromolecules (CERM), University of Liege, Belgium, directed by Prof. R. Jérôme. He then moved to the University of Toronto, Canada, and conducted post-doctoral research in Prof. M.K. Georges’ group, who pioneered the field of controlled radical polymerisation. In 2006, he returned to the CERM in Liege as a FNRS post-doctoral researcher and was promoted to FNRS Research Associate in 2010 in the same group. His research interests include controlled radical polymerisation, organometallic chemistry, macromolecular engineering and emulsion polymerisation.

To find out more about the CERM please follow the link.

What was your inspiration in becoming a chemist?

Several members of my family are scientists, even chemists, so “I fell early into chemistry”. During my scholarship, I also met excellent science teachers who taught me how important science is for understanding the world we are living in. So, I decided to make it my job. Among all scientific fields, I chose chemistry because it appeared to me as a central and practical discipline.

What was the motivation to write your Polymer Chemistry article?

Recent progress in controlled radical polymerisation (CRP) is impressive. The increasing precision and complexity of polymer structures achievable and their use in a broad range of applications might suggest that challenges in CRP may soon be non-existent. However, this is not the case and efforts still need to be expended to improve the existing tools and discover new ones in order to finely tune polymer properties. This is what the present Polymer Chemistry article is about. Indeed, poly(N-vinylcaprolactam) (PNVCL) combines valued properties such as water solubility, biocompatibility and thermo-responsiveness, but has not reached its full potential so far due to limitations in macromolecular engineering techniques. Nevertheless, the Organometallic-Mediated Radical Polymerisation (OMRP), a CRP method developed in the lab for many years, permitted us to produce a series of well-defined N-vinylcaprolactam and N-vinylpyrrolidone-based copolymers including statistical, diblock and triblock copolymers, having single or dual thermo-responsive behaviour in water. The high level of control afforded by OMRP allowed us to highlight the crucial impact of the copolymer composition, block length and architecture on the cloud point temperature of each segment and to tune their multistep assembly behaviour. The reversible temperature triggered assembly of such block copolymers in water opens new perspectives in the field of stimuli-responsive encapsulation/release applications.

Why did you choose Polymer Chemistry to publish your work?

My co-authors and I chose Polymer Chemistry because it provides high quality manuscripts in polymer science to a broad audience. This last aspect was crucial in the selection of a journal because our contribution contains progress in both macromolecular engineering and characterisation of the thermal response of copolymers in solution.

In which upcoming conferences may our readers meet you?

My agenda is still unclear for the next few months but I really would like to attend the Gordon Research Conference on Polymers, South Hadley, MA, USA  in June 2015.

How do you spend your spare time?

I enjoy spending time with my 6-year old son, friends and relatives. I also like reading novels and practice more and more photography. In this respect, I warmly recommend a visit to the photography museum of Charleroi in Belgium.

Which profession would you choose if you were not a scientist?

Maybe architect because this profession requires both technical and artistic skills. Having said that, I have no regret at all.

One of my pictures. “Building reflected on water”



Double thermo-responsive hydrogels from poly(vinylcaprolactam) containing diblock and triblock copolymers

Jean-Michel Thomassin,  Kevin Mathieu,   Anthony Kermagoret,   Charles-André Fustin,   Christine Jérôme and   Antoine Debuigne

The thermally-induced gelation and gel properties of concentrated aqueous solutions of double thermoresponsive poly(N-vinylamide)-based di- and triblock copolymers are studied by rheology. The copolymers under investigation, prepared by cobalt-mediated radical polymerisation and coupling reactions, are composed of poly(vinylcaprolactam) (PNVCL) blocks and of a statistical poly(vinylcaprolactam-stat-vinylpyrrolidone) segment with a cloud point temperature (TCP) higher than that of PNVCL. Heating the di- and triblock solutions beyond the first phase transition temperature favours gel formation while heating above the second TCP leads to opaque gels without macroscopic demixing. Moduli of the triblock hydrogels are systematically higher than those of the corresponding diblocks, even above the second transition. Rheological data suggest distinct micellar structures for each copolymer architecture: densely packed micelles of diblocks and 3-D networks of bridged micelles for triblocks. Strain sweep experiments also emphasize the positive effect of the micelle bridging on the elasticity and stability of the hydrogels. The formation and properties of the obtained gels are also shown to depend on the copolymer concentration, block length, and composition. Addition of salt also allows us to tune the phase transition temperatures of these double thermoresponsive hydrogels.


Cyrille Boyer is a guest web-writer for Polymer Chemistry. He is currently an Associate Professor and an ARC-Future Fellow in the School of Chemical Engineering, University of New South Wales (Australia).



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Paper of the week: Titin-mimicking polycyclic polymers with shape regeneration and healing properties

Schuetz et al. describe polycyclic polymers with shape regeneration and healing properties.

Polycyclic polymers based on cyclic (ABC)n-multiblock-copolymers are formed via stepwise polymerization of three individual blocks and exploiting the ring merging reaction of these ring polymers. The so-obtained precursor ring-polymers were interconnected via click reaction. Small blocks within the rings with the ability to form self-complementary hydrogen bonds lead to intra- and intermolecular links between polycyclic polymers. The obtained materials, which mimic nature’s paragon Titin, have some extraordinary material properties concerning elasticity and energy dissipation.

Titin-mimicking polycyclic polymers with shape regeneration and healing properties by Jan-Hendrik Schuetz, Peng Wentao and Philipp Vana, Polym. Chem., 2015,6, 1714-1726.

Remzi Becer is a web-writer and Advisory Board member for Polymer Chemistry. He is currently a Senior Lecturer in Materials Science and the director of the Polymer Science and Nanotechnology masters programme at Queen Mary, University of London. Visit www.becergroup.com for more information.

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Paper of the week: A fast track strategy toward highly functionalized dendrimers with different structural layers

Sharma et al. describe a fast track strategy toward highly functionalized dendrimers with different structural layers: an “onion peel approach”

An accelerated strategy depending on different chemical building blocks between each layer, coined “onion peel”, was used to construct a library of third generation dendrimers with 108, 180 and 252 hydroxyl surface groups using a combination of microwave assisted highly efficient CuAAC and thiol–ene reactions. These dendrimers were conveniently acquired with high purity and good yields in a divergent manner using a variety of orthogonal and dense AB3, AB5, and AB7building blocks. The resulting polyhydroxylated dendrimers tested in several human cell types did not impair mitochondrial metabolic function or cell viability suggesting that they are good candidates for applications in biological investigations.

A fast track strategy toward highly functionalized dendrimers with different structural layers: an “onion peel approach” by Rishi Sharma, Issan Zhang, Leïla Abbassi, Rabindra Rej, Dusica Maysinger and René Roy, Polym. Chem., 2015, 6, 1436-1444.

Remzi Becer is a web-writer and Advisory Board member for Polymer Chemistry. He is currently a Senior Lecturer in Materials Science and the director of the Polymer Science and Nanotechnology masters programme at Queen Mary, University of London. Visit www.becergroup.com for more information.

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Author of the Month: Prof. Feihe Huang

Feihe Huang was born in Shaodong, Hunan, China in 1973. He obtained his Bachelor of Polymer Materials Science and Engineering degree from Hefei University of Technology in July 1996 and a Masters in Polymer Chemistry and Physics from the University of Science and Technology of China in July 1999. After a year of studying at the University of Washington, he transferred to Virginia Polytechnic Institute and State University (VT) where he joined Prof. Harry W. Gibson’s group in August 2000. He earned the degree of Master of Science in Chemistry in August 2003. He finished his coursework and research for his PhD in Chemistry during the spring of 2005 with the aid and guidance of Prof. Harry W. Gibson. He joined Prof. Peter J. Stang’s group at the University of Utah as a postdoctoral fellow in March 2005. In December 2005, he became a professor of chemistry at the Department of Chemistry, Zhejiang University. In March 2008, he became a Qiushi Chair Professor of Zhejiang University. His current research interests are supramolecular polymers and pillar[n]arene supramolecular chemistry.

Awards and honours he has received to date include the William Preston Award for a MS Thesis from VT, a 2004 Chinese Government Award for Outstanding Self-Financed Students Abroad, The Sigma Xi Research Award for Ph.D. Degree Candidates from the VT Chapter of Sigma Xi Research Society, Outstanding Ph.D. Dissertation Award from VT, the Thieme Chemistry Journals Award, the Outstanding Recent Graduate Alumnus Award from VT, a Humboldt Fellowship for Experienced Researchers from the Humboldt Foundation, The National Science Fund for Distinguished Young Winner (China), Fellow of the Royal Society of Chemistry, and the Chinese Chemical Society AkzoNobel Chemical Sciences Award. He has published more than 160 supramolecular chemistry papers in journals such as PNAS (2), J. Am. Chem. Soc. (18), Angew. Chem., Int. Ed. (5), Adv. Mater. (5), Chem. Soc. Rev. (5), Acc. Chem. Res. (5), Prog. Polym. Sci. (1). His publications have been cited more than 7700 times and he has a h-index of 49. He has served as a guest editor for Chem. Soc. Rev.Acc. Chem. Res.Chem. Rev.and Chem. Commun. He currently sits on the Advisory Boards of Chemical Society ReviewsChemical Communications, Acta Chim. SinicaMacromoleculesACS Macro Letters and Polymer Chemistry.

For more information about Feihe Huang’s research group visit the website

What was your inspiration in becoming a chemist?

I wanted to make new materials for us to have better lives and a greener world.

What was the motivation to write your Polymer Chemistry article?

Supramolecular crosslinked polymer gels have tremendous potential as smart materials because they offer a special combination of the elastic behaviour of solids and the microviscous properties of fluids. From many published reports related to supramolecular crosslinked polymer gels, one can reach two general conclusions: 1) there are many kinds of non-convalent interactions that can be used to crosslink polymeric chains to yield supramolecular gels and 2) usually these supramolecular gels contain only one kind of noncovalent crosslink. The consequence of using a single type of supramolecular crosslink is that above some level of external stimulation, sufficient cross-links are broken and subsequently a gel to sol transition usually occurs. This transition, which can occur across a narrow stimulus window, can limit applications in several ways. In order to solve this problem, we are interested in the fabrication of supramolecular crosslinked polymer gels containing two types of physical crosslinks based on two orthogonal supramolecular interactions. In such a system, one supramolecular crosslink can be used to maintain the gel state and the other to change the crosslinking density of the gel under external stimuli, thereby giving rise to the macroscale expansion-contraction behaviour of the gel without the gel-sol transition. The roles of the two networks can be reversed, allowing for a multi-responsive, expansion-contraction system that will be more adaptive. Finally, addition of both stimuli will allow breakdown of the gel. In this Polymer Chemistry article, we report that exactly such a double supramolecular crosslinked polymer gel based on hydrogen bonding and a macrocycle threading process achieves these properties.

Why did you choose Polymer Chemistry to publish your work?

Firstly, Polymer Chemistry is a very good journal and it is great to publish my work in it. Secondly, I am an Advisory Board member for Polymer Chemistry and I want to contribute to the development of this journal.

In which upcoming conferences may our readers meet you?

I am attending the First Artificial Molecular Switches and Motors Gordon Research Conference which will be held at Stonehill College, Easton, MA (USA) on 7th-12th June 2015. Follow the link for more information about this conference.

How do you spend your spare time?

Playing with my son, reading, listen to music, and travelling.

Which profession would you choose if you were not a scientist?

I would be a high-school teacher because I want to work with and help young people.


Feihe Huang's group


A double supramolecular crosslinked polymer gel exhibiting macroscale expansion and contraction behavior and multistimuli responsiveness

Xiaofan Ji, Kecheng Jie, Steve Zimmerman and Feihe Huang

Supramolecular crosslinked polymer gels show special properties largely as a result of the combined mechanical properties contributed by the covalently linked polymer chains and the reversible, stimuli-responsive supramolecular crosslinks. Most supramolecular crosslinked polymer gels contain only one kind of physical cross-link. Herein we report a novel supramolecular polymer gel containing two types of physical crosslinks based on two kinds of non-covalent interactions that are orthogonal: DAN-DeUG quadruply hydrogen-bonding interactions and benzo-21-crown-7/dialkylammonium salt host-guest interactions. One of the crosslinked networks is used to maintain the gel state while the other modulates the crosslink density through an external stimuli, thereby causing a volume change of the gel. This double supramolecular crosslinked polymer gel shows macroscale expansion and contraction behaviour and multistimuli responsiveness. Therefore, we successfully demonstrate that the macroscopic property changes of supramolecular systems can be induced by controlled self-assembly on the molecular scale.


Cyrille Boyer is a guest web-writer for Polymer Chemistry. He is currently an Associate Professor and an ARC-Future Fellow in the School of Chemical Engineering, University of New South Wales (Australia) and deputy director of the Australian Centre for NanoMedicine.


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Paper of the week: Dynamic intracellular delivery of antibiotics via pH-responsive polymersomes

Lane et al. report the intracellular delivery of antibiotics via pH-responsive polymersomes.

Reversible addition-fragmentation chain transfer (RAFT) polymerisation was employed to prepare a series of copolymers consisting of 2-hydroxyethyl methacrylate (HEMA) and poly(ethylene glycol) methyl ether methacrylate (FWavg [similar] 950 Da) (O950) with variable comonomer compositions and molecular weights for use as polymeric scaffolds. Reactivity ratios for the monomer pair were determined to be 1.37 and 0.290 respectively. To these scaffolds, trithiocarbonate-based RAFT chain transfer agents (CTAs) were grafted using carbodiimide chemistry. The resultant graft chain transfer agents (gCTA) were subsequently employed to polymerise dimethylaminoethyl methacrylate (DMAEMA) and N-(2-hydroxypropyl)methacrylamide (HPMA) between degrees of polymerisation (DP) of 25 and 200. Kinetic analysis for the polymerisation of DMAEMA targeting a DP of 100 from a 34 arm graft gCTA show linear Mn conversion and pseudo first order rate plots with narrow molecular weight distributions that move toward lower elution volumes with monomer conversion. Đ values for these polymerisations remain low at around 1.20 at monomer conversions as high as 70%. pH-responsive endosomalytic brushes capable of spontaneously self-assembling into polymersomes were synthesised and a combination of dynamic light scattering (DLS), cryoTEM, and red blood cell haemolysis were employed to evaluate the aqueous solution properties of the polymeric brush as a function of pH. Successful encapsulation of ceftazidime and pH-dependent drug release properties were confirmed by HPLC. Intracellular antibiotic activity of the drug-loaded polymersomes was confirmed in a macrophage coculture model of infection with Burkholderia thailandensis and RAW 264.7 cells.

Dynamic intracellular delivery of antibiotics via pH-responsive polymersomes by D. D. Lane, F. Y. Su, D. Y. Chiu, S. Srinivasan, J. T. Wilson, D. M. Ratner, P. S. Stayton and A. J. Convertine, Polym. Chem., 2015,6, 1255-1266.

Remzi Becer is a web-writer and Advisory Board member for Polymer Chemistry. He is currently a Senior Lecturer in Materials Science and the director of the Polymer Science and Nanotechnology masters programme at Queen Mary, University of London. Visit www.becergroup.com for more information.

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IP’15 – International Symposium on Ionic Polymerization

IP’15 - International Symposium on Ionic Polymerization

The 11th International Symposium on Ionic Polymerization (IP’15) will be held at Bordeaux University in the South West of France from 5th – 10th July 2015, organized and hosted by the Polymer Institute.

IP’15 will be the latest in a series of successful meetings, the most recent of which were held in Awaji (Japan, 2013), Akron (USA, 2011), Krakow (Poland, 2009), Kloster Banz (Germany, 2007), Goa (India, 2005), Boston (USA, 2003), Crete (2001, Greece).

IP’15 has roots from the series of international symposia on Cationic, Anionic, and Ring-Opening Polymerizations, which were merged as International Symposium on Ionic Polymerization in 1995, held in Istanbul (Turkey). Decision of the merger was made in the 11th International Symposium on Cationic Polymerization and Related Processes, held in Borovetz, Bulgaria, in 1993, with the recognition of closer relationship and interplay among these polymerization methods, in view of precise control of polymer structures and macromolecular architectures. Thus this symposium on Ionic Polymerization will be the 22nd symposium as the Cationic series as well as the 11th one named “Ionic Polymerization“.

Topics will cover academic and applied research in the areas of anionic, cationic, and related polymerization mechanisms. Contributions related to other methods of living/controlled polymerization (catalytic, controlled free-radical, and step-growth polymerizations) are welcome, as well as industrial applications and processes of these well-controlled polymerizations. For further details about the conference visit the website or email the organising committee.

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Paper of the week: Efficient microencapsulation of a liquid isocyanate with in situ shell functionalization

Nguyen et al. outline the efficient microencapsulation of a liquid isocyanate with in situ shell functionalization.

Nguyen et al. report on a one-pot, facile approach for the encapsulation of the liquid hexamethylene diisocyanate isocyanurate trimer in polyurea microcapsules formed via the oil-in-water interfacial reaction of an uretonimine-modified diphenyl methane diisocyanate trimer with triaminopyrimidine; with in situ shell functionalization/modification using different types of hydrophobic agents. Remarkably, the use of hexamethylenedisilazane resulted in microcapsules of about 70 μm in diameter, with a smooth outer surface and a high isocyanate core content up to 85 wt% as determined by quantitative online FT-IR analysis of the extracted core. On the other hand, the use of an alkylamine, fluorinated aromatic amine and/or perfluoride amine provided microcapsules of approximately 100 to 150 μm in diameter containing around 65–75 wt% of the isocyanate core content, with the outer shell surface bearing pendant hydrophobic groups as confirmed by SEM-EDX. The effects of the functionalizing compound on the microcapsule properties such as shell morphology, size distribution and stability were assessed. After one day immersion in water, the initial isocyanate content of the microcapsules with a non-functionalized shell dropped rapidly from 49 to 15 wt%, whereas the ones with the modified shell structure maintained their core content, suggesting a significantly enhanced microcapsule stability.

Efficient microencapsulation of a liquid isocyanate with in situ shell functionalization by Le-Thu T. Nguyen, Xander K. D. Hillewaere, Roberto F. A. Teixeira, Otto van den Berg and Filip E. Du Prez, Polym. Chem., 2015, 6, 1159-1170.

Remzi Becer is a web-writer and Advisory Board member for Polymer Chemistry. He is currently a Senior Lecturer in Materials Science and the director of the Polymer Science and Nanotechnology masters programme at Queen Mary, University of London. Visit www.becergroup.com for more information.

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Author of the Month: Prof. Jacques Lalevée

Prof. Jacques Lalevée was born in Remiremont (France) in 1976. After studying Physical Chemistry at the University of Nancy (now University of Lorraine), he received his Ph.D. degree in Materials Chemistry under the supervision of Prof. Jean Pierre Fouassier from Mulhouse in 2002. After approximately one-year of postdoctoral research with Prof. Gerd Kothe (Germany), he joined the “Ecole Nationale Supérieure de Chimie de Mulhouse (ENSCMu)” in September, 2004. He was promoted to full professor in September, 2009. Since 2011, Jacques has been a Professor at the “Institut Universitaire de France (IUF-Paris)”. His current research interests encompass free radical chemistry, the design of new (photo)polymerisation initiating systems and new polymers, as well as mechanistic elucidation in polymer chemistry. He has published nearly 200 peer-reviewed papers with an H-index of 29.

He was awarded the Guy Ourisson 2013 Prize as well as the national prize of the French polymer group (GFP) in 2014.

What was your inspiration in becoming a chemist?

I became really interested in chemistry at high school. I was fascinated by chemical reactions and the possibility of understanding events at this molecular scale. I have always been interested in free radical chemistry as many different reaction pathways can be expected from these chemical species. The “positive” use of free radicals in polymerisation processes was always a challenge for me; particularly the possibility of triggering processes by light for perfect time and spatial controls.

What was the motivation to write your Polymer Chemistry article?

Light-induced polymerisation technique is a promising approach for the fabrication of various polymeric materials due to its environmental, economic and production benefits. This technique is mainly based on the photochemically generated reactive species (e.g. radicals or cations, produced from the photochemical reactions of photoinitiating systems after the absorption of light) to rapidly transform the specially formulated reactive liquids to solids (3D polymeric networks for various materials) at room temperature. Recently, light-emitting diodes (LEDs) have attracted increased attention as potential irradiation sources for photopolymerisation processes substituting traditional mercury UV lamps; their advantages include being more environmentally friendly, having better light output, higher operating efficiency and lower cost and energy consumption.

Recently, the use of metal based complexes as photoredox catalysts in polymer science has generated lots of interest and is actually a huge challenge. In the present paper, we propose a new iridium complex (Ir(btp)2(tmd)) as a novel photoredox catalyst with enhanced efficiency under visible lights (laser diodes, LEDs and household halogen lamp) for i) cationic polymerisation, ii) free radical polymerisation, iii) controlled/living radical polymerisation and iv) polymer surface modification, including micropatterning by laser direct writing.

Why did you choose Polymer Chemistry to publish your work?

The Royal Society of Chemistry is clearly one of the leading societies and accordingly its polymer journal “Polymer Chemistry” has rapidly emerged as a leader journal in Polymer Science. The wide international readership, the quick submission and review system are also particularly interesting.

In which upcoming conferences may our readers meet you?

The European Polymer Congress (Dresden, Germany in June 2015) or 11th International Symposium on Ionic Polymerization (Bordeaux – France July 2015).

How do you spend your spare time?

Obviously, I am willing to spend more time with my family. I like cycling, and would like to dedicate more time to it.

Which profession would you choose if you were not a scientist?

I would become a teacher in middle school, it was my original idea, but I met excellent professors in the University and they have opened my mind to research.


Photoredox catalysis using a new iridium complex as an efficient toolbox for radical, cationic and controlled polymerizations under soft blue to green lights

Sofia Telitel, Frederic Dumur, Siham Telitel, Olivier Soppera, Marc Lepeltier, Yohann Guillaneuf, Julien Poly, Fabrice Morlet-Savary, Philippe Fioux, Jean-Pierre Fouassier, Didier Gigmes and Jacques Lalevée

A new iridium complex (nIr) was designed and investigated as a photoinitiator catalyst for radical and cationic polymerization upon very soft irradiations (lights ranging from 457 to 532 nm). A ring-opening polymerization (ROP) of an epoxy monomer was easily promoted through the interaction between nIr and an iodonium salt (Iod) upon light. In radical polymerization, nIr can be efficient in combination with phenacyl bromide (PBr) and optionally an amine. These photoinitiating systems work according to an original oxidative cycle and a regeneration of nIr is observed. A control of the methyl methacrylate polymerization (conducted under a 462 nm light) with 1.2–1.6 polydispersity indexes was displayed. Surface modifications by direct laser write was also easily carried out for the first time through surface re-initiation experiments, i.e. the dormant species being reactivated by light in the presence of nIr; the polymer surfaces were analyzed by XPS. The chemical mechanisms were examined through laser flash photolysis, NMR, ESR and size exclusion chromatography experiments.


Cyrille Boyer is a guest web-writer for Polymer Chemistry. He is currently an Associate Professor and an ARC-Future Fellow in the School of Chemical Engineering, University of New South Wales (Australia).


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Paper of the week: Highly regioselective Pd/C-catalyzed direct arylation toward thiophene-based π-conjugated polymers

Hayashi et al. have successfully developed a highly regioselective Pd/C-catalysed direct arylation toward thiophene-based π-conjugated polymers.

Pd/C heterogeneous catalysts were used in the direct arylation polycondensation of thiophenes. The efficient and highly regioselective polycondensation of thiophene monomers was achieved under phosphine-free conditions to give linear π-conjugated alternating copolymers with high molecular weight in high yield.

Highly regioselective Pd/C-catalyzed direct arylation toward thiophene-based π-conjugated polymers by Shotaro Hayashi, Yoshihisa Kojima and Toshio Koizumi Polym. Chem., 2015,6, 881-885.

Remzi Becer is a web-writer and Advisory Board member for Polymer Chemistry. He is currently a Senior Lecturer in Materials Science and the director of the Polymer Science and Nanotechnology masters programme at Queen Mary, University of London. Visit www.becergroup.com for more information.

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