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Macromolecular Rapid Communications

Lun Peng, Zhiyun Li, Xiaohui Li, Hui Xue, Weidong Zhang, Gaojian Chen
Glycopolymers attached to a surface possess the ability to bind to certain carbohydrate binding proteins in a highly specific manner, and because of this, the fabrication of glycopolymer-modified surfaces has evolved as an effective route toward bioresponsive systems. Poly(N-3,4-dihydroxybenzenethyl methacrylamide-co-2-(methacrylamido) glucopyranose) copolymers, containing sugar and catechol functionalities, are for the first time successfully prepared in a well-controlled manner via room temperature single-electron transfer initiation and propagation through radical addition fragmentation chain transfer technique...
December 1, 2016: Macromolecular Rapid Communications
Yiwen Pei, Andrew B Lowe, Peter J Roth
Polymerization-induced self-assembly (PISA) is an extremely versatile method for the in situ preparation of soft-matter nanoparticles of defined size and morphologies at high concentrations, suitable for large-scale production. Recently, certain PISA-prepared nanoparticles have been shown to exhibit reversible polymorphism ("shape-shifting"), typically between micellar, worm-like, and vesicular phases (order-order transitions), in response to external stimuli including temperature, pH, electrolytes, and chemical modification...
November 30, 2016: Macromolecular Rapid Communications
Silvana Hurrle, Andrea Lauer, Hartmut Gliemann, Hatice Mutlu, Christof Wöll, Anja S Goldmann, Christopher Barner-Kowollik
An alkyne functional radical photoinitiator, 2-(4-(2-hydroxy-2-methylpropanoyl)phenoxy)ethyl hex-5-ynoate, and evidence that both reactive moieties - the alkyne and the photoinitiator terminus - can be independently addressed with light of disparate wavelength (λ-orthogonality) are introduced. The alkyne functionality is subjected to a visible light (420 nm) induced copper-catalyzed Huisgen reaction, which is employed for the selective functionalization of the initiator with a poly(ethylene glycol) (PEG) chain...
November 29, 2016: Macromolecular Rapid Communications
Jinlong Zhang, Nan Shi, Jie Zhang, Yan Guan, Weihong Qiao, Xinhua Wan
A novel co-assembly based on the block copolymer bearing photocleavable groups and macroanionic polyoxometalates Na9 [Ln(W5 O18 )2 ] (LnW10 , Ln = Eu, Dy) triggered by UV light is realized in aqueous solution. The copolymer synthesized by atom transfer radical polymerization (ATRP) undergoes irreversible cleavage upon UV irradiation to generate primary amine (pKa ≈ 8-9) residues which are completely protonated under a neutral pH in aqueous solution. Electrostatic attractions between the resulting positively charged copolymers and anionic LnW10 drive the formation of assemblies...
November 28, 2016: Macromolecular Rapid Communications
Simon Schoelch, Jaana Vapaavuori, Frédéric-Guillaume Rollet, Christopher J Barrett
Humidity detection, and the quest for low-cost facile humidity-sensitive indicator materials is of great interest for many fields, including semi-conductor processing, food transport and storage, and pharmaceuticals. Ideal humidity-detection materials for a these applications might be based on simple clear optical readout with no power supply, i.e.: a clear color change observed by the naked eye of any untrained observer, since it doesn't require any extra instrumentation or interpretation. Here, the introduction of a synthesis-free one-step procedure, based on physical mixing of easily available commercial materials, for producing a humidity memory material which can be easily painted onto a wide variety of surfaces and undergoes a remarkable color change (approximately 100 nm blue-shift of λMAX ) upon exposure to various thresholds of levels of ambient humidity is reported...
November 23, 2016: Macromolecular Rapid Communications
Gaigai Duan, Melissa Koehn-Serrano, Andreas Greiner
This study reports on gold nanoparticles (AuNPs) immobilized in a sponge made of short electrospun fibers (Au-sponge), which show surprisingly high reaction rates at extremely low gold amount. Au-sponges are made by freeze-drying of dispersions of short electrospun fibers with preimmobilization of AuNPs. The resulting Au-sponges show very low densities around 7 mg cm(-3) corresponding to a pore volume of about 150 mL g(-1) , but low surface area and very low amount of AuNPs in the range of 0.29-3.56 wt%. In general, catalysts with immobilized AuNPs show much low reaction rates compared to systems with dispersed AuNPs...
November 23, 2016: Macromolecular Rapid Communications
Gregory T Carroll, Jeffrey R Lancaster, Nicholas J Turro, Jeffrey T Koberstein, Angela Mammana
This report demonstrates the electroless deposition of Ni onto micropatterns of poly (acrylic acid) (PAA) photografted to phthalimide-terminated self-assembled monolayers (SAMs). PAA is spin-coated onto phthalimide SAMs and covered with a photomask. UV irradiation selectively binds PAA to exposed regions of the surface, allowing PAA on unexposed regions to be rinsed off. A Pd catalyst is then selectively adsorbed to regions of the surface where PAA is bound. The adsorbed catalyst selectively initiates Ni plating upon immersion of the substrate into a Ni(SO4 ) bath...
November 22, 2016: Macromolecular Rapid Communications
Ye Sha, Dongliang Qi, Shaochuan Luo, Xinghua Sun, Xiaoliang Wang, Gi Xue, Dongshan Zhou
Novel difunctional initiators that incorporate Förster/fluorescence resonance energy transfer (FRET) pairs are generated to carry out atom transfer radical polymerization of styrene, methyl methacrylate, and n-butyl methacrylate monomers by an efficient manner. Based on the chemical structures of the initiators, the locations of the fluorophore moiety are dictated to be in the center of the chain with accurately quantified chain functionality (>90% labeling ratio). The site-specific integration of FRET dyes into separate polymer chain centers allows for characterization of the well-defined interchain distance quantitatively based on the response between these fluorescent probes...
November 22, 2016: Macromolecular Rapid Communications
Xiaojin Zhang, Yu Dai
Biodegradable and bioabsorbable poly(lactic acid)s are one of the most important biomedical materials. However, it is difficult to introduce the functional groups into poly(lactic acid)s in order to improve their hydrophilicity and degradation rate. Here the authors describe the synthesis of functionalized cyclic lactide monomer 3,6-bis(benzyloxymethyl)-1,4-dioxane-2,5-dione (BnLA) using an advanced synthetic route. Water-soluble hydroxyl-functionalized homopoly(lactic acid) (P(OH)LA) is synthesized via ring-opening polymerization (ROP) of BnLA, followed by a hydrogenolytic deprotection reaction...
November 18, 2016: Macromolecular Rapid Communications
Mathamsanqa N Bhebhe, Eva Alvarez De Eulate, Yiwen Pei, Damien W M Arrigan, Peter J Roth, Andrew B Lowe
(Co)Polymers containing pentafluorophenylacetylene (F5 PA) have been prepared for the first time mediated by [Rh(nbd)Cl]2 /NEt3 to give materials with properties typical of poly(phenylacetylene)s prepared with this catalyst/co-catalyst combination. It is demonstrated that the F5 PA repeat units in these new (co)polymers serve as convenient reactive species for post-polymerization modification with thiols via para-fluoro aromatic nucleophilic substitution reactions to give an entirely new family of novel thioether-functional polyene materials accompanied by absorption maxima shifts of up to 130 nm...
November 18, 2016: Macromolecular Rapid Communications
Merid Haile, Owais Sarwar, Robert Henderson, Ryan Smith, Jaime C Grunlan
Multilayer coatings consisting of oppositely charged polyelectrolytes have proven to be extraordinarily effective oxygen barriers but require many processing steps to fabricate. In an effort to prepare high oxygen barrier thin films more quickly, a polyelectrolyte complex coacervate composed of polyethylenimine and polyacrylic acid is prepared. The coacervate fluid is applied as a thin film using a rod coating process. With humidity and thermal post-treatment, a 2 µm thin film reduces the oxygen transmission rate of 0...
November 18, 2016: Macromolecular Rapid Communications
Jennifer Collins, Sacha J Wallis, Alexandre Simula, Michael R Whittaker, Michelle P McIntosh, Paul Wilson, Thomas P Davis, David M Haddleton, Kristian Kempe
The controlled synthesis of poly(oligo(2-ethyl-2-oxazoline)methacrylate) (P(OEtOxMA)) polymers by Cu(0)-mediated polymerization in water/methanol mixtures is reported. Utilizing an acetal protected aldehyde initiator for the polymerization, well-defined polymers are synthesized (>99% conversion, Ð < 1.25) with subsequent postpolymerization deprotection resulting in α-aldehyde end group containing comb polymers. These P(OEtOxMA) are subsequently site-specifically conjugated, via reductive amination, to a dipeptide (NH2 -Gly-Tyr-COOH) as a model peptide, prior to conjugation to the functional peptide oxytocin...
November 17, 2016: Macromolecular Rapid Communications
Gioia Della Giustina, Stefano Giulitti, Laura Brigo, Michele Zanatta, Maximilian Tromayer, Robert Liska, Nicola Elvassore, Giovanna Brusatin
In this work, an engineered hydrogel system with a 2D and 3D tunable cross-linking degree is presented. A precise chemical design by the introduction of cross-linkable units, having reaction orthogonality, allows to control the network formation both in time and space and to selectively alter the hydrogel physical properties. Hydrogel chemistry has been tailored in order to produce spatially controlled stiffness changes and drive cell morphology through mechanical cues. Elastic modulus rises by more than double after photocross-linking, as shown by atomic force microscopy measurements...
November 17, 2016: Macromolecular Rapid Communications
Jianhua Wu, Cuifang Wang, Dandan Zhou, Xiaojuan Liao, Meiran Xie, Ruyi Sun
Metathesis cyclopolymerization of mono- or bissubstituted 1,6-heptadiynes is undergone to generate the ionic polyacetylenes (iPAs) with branched 1,2,3-ttriazolium pendants, which possess relatively high intrinsic ionic conductivities of 1.4 × 10(-5) -2.1 × 10(-5) S cm(-1) at 30 °C. The doping treatment with lithium bis(trifluoromethanesulfonyl)imide endows iPAs with enhanced ionic conductivities of 2.5 × 10(-5) -4.3 × 10(-5) S cm(-1) . Further doping with iodine, iPAs show ionic and electronic dual conductivities of 4...
November 15, 2016: Macromolecular Rapid Communications
Jangwhan Cho, Seong Jong Park, Sung Min Lee, Jae Un Ha, Eun Soo Ahn, Suk Tai Chang, Soon-Ki Kwon, Dae Sung Chung, Yun-Hi Kim
A new random copolymer consisting of similarly shaped donor-acceptor building blocks of diketopyrrolopyrrole-selenophene-vinylene-selenophene (DPP-SVS) and DPP-thiophene-vinylene-thiophene (DPP-TVT) is designed and synthesized. The resulting P-DPP-SVS(5)-TVT(5) with an equal molecular ratio of the two building blocks produced significantly enhanced solubility when compared to that of the two homopolymers, PDPP-SVS and PDPP-TVT. More importantly, despite the maximum segmental randomness of the PDPP-SVS(5)-TVT(5) copolymer, its crystalline perfectness and preferential orientation are outstanding, even similar to those of the homopolymers thanks to the similarity of the two building blocks...
November 15, 2016: Macromolecular Rapid Communications
Todd Cowen, Mirko Busato, Kal Karim, Sergey A Piletsky
Molecularly imprinted polymer (MIP) synthetic receptors have proposed and applied applications in chemical extraction, sensors, assays, catalysis, targeted drug delivery, and direct inhibition of harmful chemicals and pathogens. However, they rely heavily on effective design for success. An algorithm has been written which mimics radical polymerization atomistically, accounting for chemical and spatial discrimination, hybridization, and geometric optimization. Synthetic ephedrine receptors were synthesized in silico to demonstrate the accuracy of the algorithm in reproducing polymers structures at the atomic level...
November 11, 2016: Macromolecular Rapid Communications
Tianchi Xu, Hongnan Yin, Xiaohong Li, Lifen Zhang, Zhenping Cheng, Xiulin Zhu
A new polymerization method, termed as step transfer-addition and radical-termination, is developed for the step-growth radical polymerization of α,ω-unconjugated dienes under irradiation of visible light at room temperature (25 °C) for the first time. α,ω-Diiodoperfluoroalkane monomers (signified as A) are added onto α,ω-unconjugated dienes (signified as B) alternatively and efficiently with the generation of perfluorocarbon-containing alternating copolymers (AB)n . Based on the combined analyses of polymerization kinetics and NMR spectra ((1) H and (19) F), the mechanism of the novel polymerization method, including the side reaction, is proposed...
November 11, 2016: Macromolecular Rapid Communications
Xuediao Cai, Yating Liu, Tian Lu, Rui Yang, Chuxin Luo, Qi Zhang, Yonghai Chai
This work describes the synthesis of π-conjugated polymers possessing arylene and 1,3-butadiene alternating units in the main chain by the reaction of α,β-unsaturated ester/nitrile containing γ-H with aromatic/heteroaromatic aldehyde compound. By using 4-(4-formylphenyl)-2-butylene acid ethyl ester as a model monomer, the different polymerization conditions, including catalyst, catalyst amount, and solvent, are optimized. The polymerization of 4-(4-formylphenyl)-2-butylene acid ethyl ester is carried out by refluxing in ethanol for 72 h with 1,8-diazabicyclo[5...
November 10, 2016: Macromolecular Rapid Communications
Mu-Huan Chi, Chun-Hsien Su, Ming-Hsiang Cheng, Pei-Yun Chung, Chi-How Peng, Jiun-Tai Chen
To manipulate the functions of nanomaterials more precisely for diverse applications, the controllability and critical influencing factors of their properties must be thoroughly investigated. In this work, the macroscopic and microscopic effects are studied on the photophysical properties of various pyrene-ended poly(styrene-block-methyl methacrylate) nanostructures. Fluorescent polymer nanospheres, nanorods, and nanotubes are prepared by different template-based methods using anodic aluminum oxide membranes...
November 9, 2016: Macromolecular Rapid Communications
Xuan Zhang, Youpeng Wang, Guo Li, Zhaotie Liu, Zhongwen Liu, Jinqiang Jiang
An amphiphilic block copolymer of poly(ethylene oxide)-b-poly((N-methacryloxy phthalimide)-co-(7-(4-vinyl-benzyloxyl)-4-methylcoumarin)) (PEO45 -b-P(MAPI36 -co-VBC4 )) is designed to improve the micellar stability during the photo-triggered release of hydrophobic cargoes. Analysis of absorption and emission spectra, solution transmittance, dynamic light scattering, and transmission electron microscopy supports that polymer micelles of PEO45 -b-P(MAPI36 -co-VBC4 ) upon the combinational irradiation of 365 and 254 nm light can be solubilized through the photolysis of phthalimide esters and simultaneously crosslinked via the partially reversible photo-dimerization of coumarins...
November 4, 2016: Macromolecular Rapid Communications
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