The unusual shape memory properties in animal hair could be a basis for the development of new smart materials.
Read the full story by Emma Cooper in Chemistry World
This article is free to access until 10 October 2016
X Xiao et al., Polym. Chem., 2016, DOI: 10.1039/C6PY01283C
Athina Anastasaki selects her paper of the month.
Gavrilov et al. report the quantitative and in situ functionalization of PNIPAM in aqueous media.
One major issue in aqueous copper mediated approaches is the hydrolysis of the halide end group which significantly compromises the end group fidelity of the resulting materials and therefore limits post polymerization modifications. In this current contribution, Monteiro and co-workers have carefully investigated the kinetics of hydrolysis of poly(N-isoproplyacrylamide) (PNIPAM) obtained via a new single electron transfer (SET) polymerization method to reduce Cu(II) directly and quantitatively to Cu(0). It was shown that the rate of hydrolysis is independent of the molecular weight of the polymer and the copper content in solution and reaches completion in approximately 15 hours.
In order to circumvent the hydrolysis issue, the authors elegantly conducted an in situ azidation of the bromine end group resulting in the quantitative transformation of the bromine end groups in a matter of 30 seconds, as indicated by matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-ToF-MS). This is quite a remarkable achievement given that organic solvents facilitate the same process in much longer reactions times, ranging from 10 to 24 hours. The fast reaction rate can be attributed to the enhanced solubility of sodium azide in water and the greater ion pair separation that facilitates nucleophilic attack.
In an attempt to further confirm the data obtained by MALDI-ToF-MS, the azide terminated PNIPAM was subsequently coupled to alkyne functional polymers (after purification) with coupling efficiencies greater than 97%. Thus, it was demonstrated that this approach can not only overcome the hydrolysis issues but also allow rapid synthesis of functional materials.
Tips/comments directly from the authors:
Read this exciting research for free until 30/09/2016 through a registered RSC account:
M. Gavrilov, Z. Jia,, V. Percec and M.J. Monteiro
Polym. Chem., 2016, 7, 4802-4809
DOI: 10.1039/C6PY00968A
—————-
About the webwriter
Dr. Athina Anastasaki is a web writer for Polymer Chemistry. She is currently an Elings fellow working alongside Professor Craig Hawker at the University of California, Santa Barbara (UCSB).
Highlights by Dr. Fiona Hatton (@fi_hat)
Cationic polymerisation is a type of chain growth polymerisation which proceeds through the reaction of a cationic initiator with monomer, followed by further propagation. Cationic “living” polymerisation is well-known to produce precise polymers with narrow molecular weight distributions. Initial investigations in cationic polymerisation were reported as early as the beginning of the 20th century, whilst further developments in the 1970s and 80s have led to vast growth in this field of study. Now, many different monomer types can be successfully polymerised, including: styrenic, vinyl ethers, isobutene, and heterocyclic monomers, such as: lactones, lactams and cyclic amines.
Three articles appearing in Polymer Chemistry this month have described the use of cationic polymerisation to polymerise either oxazolidine based monomers or p-methylstyrene. In the case of the cyclic oxazolidine monomers the polymerisation is termed cationic ring-opening polymerisation, and in both cases the resulting polymers are interesting for biomedical applications. The polymerisation of p-methylstyrene was conducted in ionic liquids as a green substitute for organic solvents.
1. Cationic ring-opening polymerization of protected oxazolidine imines resulting in gradient copolymers of poly(2-oxazoline) and poly(urea)
Meike N. Leiske, Matthias Hartlieb, Fabian H. Sobotta, Renzo M. Paulus, Helmar Görls, Peter Bellstedt, Ulrich S. Schubert
Polym. Chem., 2016, 7, 4924-4936; DOI: 10.1039/C6PY00785F
A Boc-protected oxazolidine monomer was synthesised and utilized to prepare poly(urea)s through cationic ring opening polymerisation. The polymerisations were studied and resulting homopolymers and copolymers were characterised and subsequently deprotected. Through deprotection and solvent switch to water self-assmebled nanostructures were obtained, which will be further investigated for their biological application.
2. Cationic polymerization of p-methylstyrene in selected ionic liquids and polymerization mechanism
Xiaoqian Zhang, Wenli Guo, Yibo Wu, Liangfa Gong, Wei Li, Xiaoning Li, Shuxin Li, Yuwei Shang, Dan Yang, Hao Wang
Polym. Chem., 2016, 7, 5099-5112; DOI: 10.1039/C6PY00796A
The authors describe extensive experimental and computational investigations of the cationic polymerisation of p-methylstyrene in ionic liquids. Using quantum chemically based computations (the COSMO-RS method) following by solubility and viscosity measurements, a range of ionic lquids were screened. Subsequently, cationic polymerisation were investigated using various initiating systems.
3. Formation of polyoxazoline-silica nanoparticles via the surface-initiated cationic polymerization of 2-methyl-2-oxazoline
G. Bissadi, R. Weberskirch
Polym. Chem., 2016, 7, 5157-5168; DOI: 10.1039/C6PY01034B
Silica nanoparticles were modified to bear initiating sites to polymerise 2-methyl-2-oxazoline from the surface. This cationic surface-initiated grafting-from polymerisation resulted in higher grafting densities compared to previous grafting-to studies, and the molecular weight of the grafted polymer could be tuned by varying the monomer/initiator ratio. The resulting polymer-grafted nanoparticles were conjugated with biomolecules for fluorescence imaging and targeting for biomedical applications.
—————-
About the webwriter
Dr. Fiona Hatton is a web writer for Polymer Chemistry. She is currently a postdoctoral researcher in the Armes group at the University of Sheffield, UK. Find her on Twitter: @fi_hat
Tom Davis is a member of Advisory Board for Polymer Chemistry and the Monash–Warwick Professor of medical nanotechnology at Monash University, Australia. Prof. Davis’ research focuses on the application of polymer science and nanotechnology to therapeutic applications, and enhancing the fundamental understanding of how nanomaterials interact with biological systems.
Nghia Truong is a member of the RSC Advances Reviewer Panel and a research fellow at Monash University, Australia. His research focuses on engineering the size, shape, surface, core, and function of polymeric nanoparticles for applications in nanomedicine, using a variety of techniques including emulsion polymerization, self-assembly, polymerization-induced self-assembly, temperature-induced morphological transformation, and click chemistry.
You can find all Advisory Board’s Top Picks papers in our web collection.
Focus on nanoparticle shapes (Prof. Tom Davis, Monash University, Australia and Dr. Nghia Truong, Monash University, Australia).
Shape plays an important role in functional properties of nanoparticles, and as a result, their utility in many applications. Polymer chemists with powerful synthetic techniques have recently made significant contributions expanding our ability to make complex nano-shapes. In 2016, many excellent Polymer Chemistry publications have appeared describing the synthesis and assembly of polymers into tertiary structures. Below we highlight some that have caught our eye.
Sen Li, Jinlin He, Mingzu Zhang, Hairong Wang and Peihong Ni
Polym. Chem., 2016, 7, 1773–1781
Li et. al. self-assemble fluorinated triblock terpolymers into five types of reproducible shapes including sphere, tube, rod, hamburger, and flower. Interestingly, rod-like aggregates have a uniform zig-zag pattern. This work reveals the fact that flexibility or rigidity of hydrophobic segment and polymer concentration have a big influence on the shape of nanoparticles.
2. Disk-like micelles with cylindrical pores from amphiphilic polypeptide block copolymers
Xue Lin, Xiaohua He, Chaoqun Hu, Yuxiang Chen, Yiyong Mai and Shaoliang Lin
Polym. Chem., 2016, 7, 2815–2820
A rare and complex shape such as a nanodisk with cylindrical pores has recently been achieved by self-assembly of the amphiphilic block copolypeptide poly(ethylene glycol)-block-poly(γ-benzyl-L-glutamate) (PEG-b-PBLG) in solution. Spherical micelles and vesicles can also be prepared by tuning the ratio between the hydrophilic block and hydrophobic block in PEG-b-PBLG copolymers.
Jianbing Huang, Hanjun Zhu, Hui Liang and Jiang Lu
Polym. Chem., 2016, 7, 4761–4770
Beside traditional self-assembly, RAFT-mediated emulsion and dispersion polymerization is a very useful technique to simultaneously synthesise block copolymers and form nanoparticles with different shapes. Using this technique, Huang et. al. can crosslink and functionalise spheres, worms, and vesicles with salicylaldazine moieties. These moieties endow the nano-objects with strong orange fluorescence in water, organic solutions or solid state via an aggregation-induced emission mechanism.
Elden T. Garrett, Yiwen Pei and Andrew B. Lowe
Polym. Chem., 2016, 7, 297–301
Andrew Lowe and coworkers have reported the use of microwaves to further assist RAFT-mediated dispersion polymerization and the formation of nanoparticles with various shapes. The work shows the benefits of microwave-assisted syntheses of nanoparticles in alcoholic solvents.
E. R. Jones, M. Semsarilar, P. Wyman, M. Boerakker and S. P. Armes
Polym. Chem., 2016, 7, 851–859
Besides using a microwave, the addition of water into alcoholic solvents also increases the rate of RAFT-mediated dispersion polymerization. On the other hand, Armes and coworkers find that in the presence of water, only kinetically-trapped spheres are obtained. This work and other works using aqueous RAFT-mediated emulsion polymerizations create a currently unclear question about the mechanism of the in-situ formation of various nanoparticle shapes in water.
Review article
Theoretical simulations of nanostructures self-assembled from copolymer systems
Zhanwen Xu, Jiaping Lin, Qian Zhang, Liquan Wang and Xiaohui Tian
Polym. Chem., 2016, 7, 3783–3811
Beside powerful synthetic techniques, theoretical simulations offer a useful approach for the understanding and prediction of the formation of polymeric nanostructures. The review by Xu et al. gives a nice overview of the simulation investigations of many self-assembled nanostructures. By tailoring the molecular architectures of block copolymers, nanoparticles with desired shapes can be achieved. Challenges and further developments for theoretical simulations are also discussed in this useful review.
5th – 8th August 2016 in Dublin, Ireland
We are proud to announce the 5th Zing Polymer Chemistry Conference will take place in Dublin (Ireland).
The field of polymer chemistry has experienced a renaissance over the last few last years with the discovery of novel mechanisms to control polymer structure, molecular weight, and functionality. Moreover, the preparation of new polymeric materials with stimuli-responsive or dynamic characteristics have led to novel biomedical materials, polymers for electronic applications, and many other advanced materials. Indeed, polymer science is more exciting than ever before.
This conference will be held 5th – 8th August 2016 and will feature recent developments in the area of polymer synthesis and applied science and intends to gather researchers interested in the forefront polymer science and its future applications.
Several Editorial Board members of Polymer Chemistry will be attending:
– Eva M. Harth (Vanderbilt University): Conference Chair
– David M Haddleton (University of Warwick): Plenary speaker with the talk ‘Sulfur free RAFT in emulsion for multi-block copolymer synthesis‘
– Emily B. Pentzer (Case Western Reserve University): Invited speaker with the talk ‘Polymerization of Silyl Ketenes‘
– Masami Kamigaito (Nagoya University): Invited speaker with the talk ‘New Developments in Controlled Radical and Cationic Polymerizations‘
We look forward to welcoming you for the 5th Zing Polymer Chemistry Conference!
19-23 September in France
The JEPO 2016 congress enables young researchers in polymer science to present and share their work with their peers (young and senior colleagues) in a privileged environment.
The 44th edition of the French Journées d’Etudes des Polymères will take place on the seaside at the VVF “Le Moulin de Praillane” at Piriac-sur-Mer from 19-23 September 2016
The congress in open to any contribution related to polymer science, ranging from synthesis and physico-chemical properties to applications, and from industrial and academic background.
The event will consist of seven invited conferences from renowned academic and industrial English and French scientists (45 min) and oral contributions from the congress participants (20 min). The language of the congress will be English.
Registration dates:
Submission dates:
Mark your calendar today and register now!
Highlights by Dr. Fiona Hatton (@fi_hat)
This month we focus on articles describing polymers designed for the detection of small organic molecules, published in Polymer Chemistry.
Here, polymers have been reported which, through incorporation of either functional groups or varying structural architecture, could be used to detect compounds including organic vapours, various anions and aromatic explosives. Detection of compounds is important in various applications, such as the detection of explosives in airports and border controls, doping in sports, contamination of water supplies and air pollution.
1. BODIPY based hyperbranched conjugated polymers for detecting organic vapors
Choong Ping Sen, Vanga Devendar Goud, Rekha Goswami Shrestha, Lok Kumar Shrestha, Katsuhiko Ariga Suresh Valiyaveettil
Polym. Chem., 2016, 7, 4213-4225; DOI: 10.1039/C6PY00847J
The authors describe the preparation of three soluble BODIPY containing hyperbranched polymers through Sonogashira coupling polymerisation. The sensing of organic solvents (toluene, benzene, acetone and methanol) was assessed using QCM, through preparing polymer films on the QCM crystal by solvent dropcasting. Varying masses adsorbed to the surface showed the different sensitivities of the hyperbranched polymers which showed a higher selectivity towards aromatic solvents.
2. Well-defined polymers containing a single mid-chain viologen group: synthesis, environment-sensitive fluorescence, and redox activity
Zhaoxu Wang, Nicolay V. Tsarevsky
Polym. Chem., 2016, 7, 4402-4410; DOI: 10.1039/C6PY00628K
Viologen containing polymers were prepared which exhibited strong fluorescence in solution. A di-functional ATRP initiator containing a viologen group was used to polymerise methyl methacrylate. The addition of salts with polarisable anions resulted in a reduction of the fluorescence, as did the presence of nitrobenzene, highlighting possible detection capabilities. In addition to this the polymers also showed efficient catalysis of the oxidation of phenylhydrazine by air.
3. Fiber-optic detection of nitroaromatic explosives with solution-processable triazatruxene-based hyperbranched conjugated polymer nanoparticles
Yuxiang Xu, Xiaofu Wu, Yonghong Chen, Hao Hang, Hui Tong, Lixiang Wang
Polym. Chem., 2016, 7, 4542-4548; DOI: 10.1039/C6PY00930A
Two conjugated polymer nanoparticle systems, based on triazatruxene and fluorine units, were prepared by Pd-catalysed Suzuki coupling in mini-emulsion. Films were assessed for their vapour detection to TNT and DNT, and were also prepared on fibre optic tips and papers. Owing to the steric hindrance of spirobifluorene units in one of the systems, the sensitivity of detection of nitroaromatic vapours was increased in solid state and TNT was visually detectable using the coated paper.
—————-
About the webwriter
Dr. Fiona Hatton is a web writer for Polymer Chemistry. She is currently a postdoctoral researcher in the Armes group at the University of Sheffield, UK. Find her on Twitter: @fi_hat
Photolytic stability of RAFT agents under blue LED irradiation has been investigated with regard to photopolymerization reactions
McKenzie et al. report the stability of a wide range of RAFT agents during photopolymerization.
The use of external stimuli to mediate the polymerization process has recently received significant attention with light being one of the most popular stimuli mainly due to its natural abundance and the possibility for spatiotemporal control. Photopolymerizations involving reversible addition fragmentation chain transfer (RAFT) have been widely investigated and studied exhibiting impressive characteristics such as fast reaction rates, good spatiotemporal control, and high-end group fidelity.
However, a report on the stability of these RAFT agents has been clearly missing from the literature. Qiao and co-workers recently discovered an initiator-free photopolymerization where the RAFT agent is activated by a blue LED. Following this work, they have investigated the photolytic stability of a range of RAFT agents under blue light irradiation. Careful NMR studies regarding the initiation process and the induction period revealed that the photopolymerization reaction is strongly dependent on the structure of the employed trithiocarbonates (TTCs).
Degradation studies under polymerization relevant conditions showed that photolytic degradation of TTCs with more labile R-groups is observable within the reaction time scale up to 12% for a cyanosubstituted tertiary fragmenting group. On the contrary, when less stable (i.e. primary and secondary) R-group-derived radicals are employed, no degradation is detected.
Two main conclusions can be derived from these studies. Firstly, under identical photochemical conditions, the polymerization of acrylates will lead to higher end group fidelity polymers when compared to the polymerization of methacrylates. In addition, the induction period is dependent on the ability of the RAFT agent to fragment photolytically. As such, this work significantly contributes towards the understanding of the RAFT mechanism and side reactions during photopolymerization processes.
Tips/comments directly from the authors:
Read this exciting research for free until 31/08/2016 through a registered RSC account:
Investigation into the photolytic stability of RAFT agents and the implications for photopolymerization reactions
T. G. McKenzie, L. P. da M. Costa, Q. Fu, D. E. Dunstan and G. G. Qiao
Polym. Chem., 2016, 7, 4246-4253
DOI: 10.1039/C6PY00808A
—————-
About the webwriter
Dr. Athina Anastasaki is a web writer for Polymer Chemistry. She is currently an Elings fellow working alongside Professor Craig Hawker at the University of California, Santa Barbara (UCSB).
This month sees the following articles in Polymer Chemistry that are in the top 10 most accessed from April – June 2016:
Lignocellulosic biomass: a sustainable platform for the production of bio-based chemicals and polymers
Furkan H. Isikgor and C. Remzi Becer
Polym. Chem., 2015, 6, 4497-4559
DOI: 10.1039/C5PY00263J
Thiol-ene “click” reactions and recent applications in polymer and materials synthesis
Andrew B. Lowe
Polym. Chem., 2010, 1, 17-36
DOI: 10.1039/B9PY00216B
Thiol–ene “click” reactions and recent applications in polymer and materials synthesis: a first update
Andrew B. Lowe
Polym. Chem., 2014, 5, 4820-4870
DOI: 10.1039/C4PY00339J
Investigation into thiol-(meth)acrylate Michael addition reactions using amine and phosphine catalysts
Guang-Zhao Li, Rajan K. Randev, Alexander H. Soeriyadi, Gregory Rees, Cyrille Boyer, Zhen Tong, Thomas P. Davis, C. Remzi Becer and David M. Haddleton
Polym. Chem., 2010, 1, 1196-1204
DOI: 10.1039/C0PY00100G
Oxidant-induced dopamine polymerization for multifunctional coatings
Qiang Wei, Fulong Zhang, Jie Li, Beijia Li and Changsheng Zhao
Polym. Chem., 2010, 1, 1430-1433
DOI: 10.1039/C0PY00215A
Thermoresponsive polyelectrolytes derived from ionic liquids
Yuki Kohno, Shohei Saita, Yongjun Men, Jiayin Yuan and Hiroyuki Ohno
Polym. Chem., 2015, 6, 2163-2178
DOI: 10.1039/C4PY01665C
Bringing d-limonene to the scene of bio-based thermoset coatings via free-radical thiol–ene chemistry: macromonomer synthesis, UV-curing and thermo-mechanical characterization
Mauro Claudino, Jeanne-Marie Mathevet, Mats Jonsson and Mats Johansson
Polym. Chem., 2014, 5, 3245-3260
DOI: 10.1039/C3PY01302B
Effect of gold nanoparticle shapes for phototherapy and drug delivery
Nik N. M. Adnan, Y. Y. Cheng, Nur M. N. Ong, Tuan T. Kamaruddin, Eliza Rozlan, Timothy W. Schmidt, Hien T. T. Duong and Cyrille Boyer
Polym. Chem., 2016, 7, 2888-2903
DOI: 10.1039/C6PY00465B
Facile and efficient chemical functionalization of aliphatic polyesters by cross metathesis
Lucie Fournier, Carine Robert, Sylvie Pourchet, Alice Gonzalez, Lewis Williams, Joëlle Prunet and Christophe M. Thomas
Polym. Chem., 2016, 7, 3700-3704
DOI: 10.1039/C6PY00664G
Toughening of photo-curable polymer networks: a review
Samuel Clark Ligon-Auer, Martin Schwentenwein, Christian Gorsche, Jürgen Stampfl and Robert Liska
Polym. Chem., 2016, 7, 257-286
DOI: 10.1039/C5PY01631B
Why not take a look at the articles today and blog your thoughts and comments below.
Fancy submitting an article to Polymer Chemistry?
Then why not submit to us today!
To keep up-to-date with all the latest research, sign up for the e-alerts or RSS feeds, and follow us on Twitter.
Polymer Chemistry is pleased to announce that its latest Impact Factor is 5.687.
Polymer Chemistry is the home for the most innovative and exciting polymer research, with an emphasis on the synthesis of polymers and their applications. Led by Editor-in-Chief David Haddleton, and our expert team of international Associate Editors and Editorial Board members, Polymer Chemistry has the highest immediacy index (1.408) of any primary research journal in the Polymer Science category.
Immediate impact: Our Immediacy Index has been consistently higher than those of our competitors since our launch.
High citation rate: We have a higher fraction of articles cited than our competitors, with 98% of papers receiving at least 1 citation.*
Rapid publication: We have an average time from receipt to publication of just 50 days, and less than 19 days from receipt to first decision.
Continued growth: For the 6th year in a row both our number of publications and our impact factor have increased.
We are extremely grateful to all our readers, authors and referees for their contribution to Polymer Chemistry’s continued success, and to our Editorial and Advisory Board members for their hard work and dedication.
Join the many leading scientists who have already chosen to publish in Polymer Chemistry and submit today!
Find out how other Royal Society of Chemistry journals were ranked in the latest Impact Factor release.
*As of 29 June 2016, based on citations to articles published in 2013 and 2014.
