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Macromolecular Rapid Communications

Gaoyang Deng, Zhonggang Wang
The motivation of this work is to build micro and mesopores within phenolic resins to extend their applications to the heterogeneous catalysis field. For this purpose, porous hyper-cross-linked phenolic resin (PFN-P) with Brunauer-Emmett-Teller (BET) surface area of 775 m(2) g(-1) is synthesized through one-step polycondensation from tri(4-formylphenyl)phosphine and 2,5-dihydroxy-1,4-benzoquinone, which simultaneously contains abundant hydroxyl and triphenylphosphine moieties in the network. The resultant palladium-coordinated Pd@PFN-P possesses hierarchical porous structure with pore sizes ranging from 1...
November 17, 2017: Macromolecular Rapid Communications
Peixi Wang, Yishi Dong, Xiaowen Lu, Zhaoqiang Wu, Hong Chen
"Click" type reactions represent the currently most prevalent postpolymerization strategy for the preparation of functional polymeric materials. Herein, a novel photoiniferter agent 4-(fluorosulfonyl)benzyl diethylcarbamodithioate (FSB-DECT) containing both dithiocarbamates and sulfonyl fluoride moieties is developed to act as both photoinitiator and click sulfur(VI)-fluoride exchange (SuFEx) agent. The photopolymerization behavior of FSB-DECT is demonstrated via standard photoiniferter-mediated polymerization for various types of monomer including N-isopropylacrylamide (NIPAAm), glycidyl methacrylate, and vinyl acetate (VAc)...
November 16, 2017: Macromolecular Rapid Communications
Sensu Celasun, Filip E Du Prez, Hans G Börner
A straightforward access route to multifunctional block copolymers, combining a poly(ethylene glycol) (PEG) block and a monodisperse segment with discrete monomer sequence based on thiolactone chemistry, is described. Exploiting an inverse conjugation strategy on a PEG preloaded poly(styrene) synthesis resin enables the convenient introduction of a predefined PEG-block at the α-terminus of thiolactone-based sequence-defined oligomers. Reaction conditions for the stepwise, submonomer synthesis at polar solid supports are optimized, using sequential synthesis on a model resin that enables to isolate and determine the purity of the oligomer segments by liquid chromatography-electrospray ionization mass spectrometry analysis...
November 16, 2017: Macromolecular Rapid Communications
Mordjane Boukhet, Niklas Felix König, Abdelaziz Al Ouahabi, Gerhard Baaken, Jean-François Lutz, Jan C Behrends
Nanopore analysis, which is, currently, chiefly used for DNA sequencing, is also an appealing technique for characterizing abiotic polymers. As a first step toward this goal, nanopore detection of non-natural monodispersed poly(phosphodiester)s as candidate backbone structures is reported herein. Two model homopolymers containing phosphopropyl repeat units (i.e., 56 or 104 r.u.) and a short thymidine nucleotide sequence are analyzed in the present work. They are tested in two different biological nanopores, α-hemolysin from Staphylococcus aureus, and aerolysin from Aeromonas hydrophila...
November 16, 2017: Macromolecular Rapid Communications
Niklas Felix König, Sofia Telitel, Salomé Poyer, Laurence Charles, Jean-François Lutz
A photoregulated phosphoramidite iterative process is studied for the synthesis of non-natural, digitally encoded oligo(phosphodiester)s. The oligomers are prepared using two reactive phosphoramidite monomers containing a 2-(2-nitrophenyl)propoxycarbonyl (NPPOC) protected OH group. The stepwise synthesis is performed on an OH-functional soluble polystyrene support, which allows recycling by precipitation in a nonsolvent. Repeating cycles involving phosphoramidite coupling, oxidation of phosphite to phosphate, and NPPOC deprotection by light irradiation at λ = 365 nm are performed in order to prepare oligomers with different lengths and sequences...
November 16, 2017: Macromolecular Rapid Communications
Rachelle M Choueiri, Anna Klinkova, Samuel Pearce, Ian Manners, Eugenia Kumacheva
Chemical and topographic surface patterning of inorganic polymer-functionalized nanoparticles (NPs) and their self-assembly in nanostructures with controllable architectures enable the design of new NP-based materials. Capping of NPs with inorganic polymer ligands, such as metallopolymers, can lead to new synergetic properties of individual NPs or their assemblies, and enhance NP processing in functional materials. Here, for gold NPs functionalized with polyferrocenylsilane, two distinct triggers are used to induce attraction between the polymer ligands and achieve NP self-assembly or topographic surface patterning of individual polymer-capped NPs...
November 16, 2017: Macromolecular Rapid Communications
Niels Ten Brummelhuis, Patrick Wilke, Hans G Börner
Peptide sciences developed dramatically as a result of routine use of solid-phase peptide synthesis and nowadays offer a rich set of well-established strategies to design and identify functional peptide sequences for advanced applications in materials sciences. Appropriate sequences for a wide range of interesting material targets, ranging from molecules to materials surfaces and internal interfaces, can be selected via combinatorial means, and sequence specificities within the resulting peptide-target interactions can be routinely investigated...
November 7, 2017: Macromolecular Rapid Communications
Yamin Abdouni, Gökhan Yilmaz, C Remzi Becer
In this work the synthesis and use of a novel β-cyclodextrin-based single electron transfer-living radical polymerization (SET-LRP) initiator are reported. Three different approaches toward the synthesis of this initiator, based on several "click"-like reactions (copper(I)-catalyzed azide-alkyne cycloaddition, nucleophilic thiol-ene reaction, and radical thiol-ene reaction), are explored and discussed. Synthesis via radical thiol-ene proves to be most successful in achieving this. The β-cyclodextrin-based initiator is subsequently used for the polymerization of several acrylates in a controlled fashion, yielding 7-arm multiblock copolymers...
November 7, 2017: Macromolecular Rapid Communications
Feng Wang, Charles E Diesendruck
o-Phthalaldehyde is, to this day, the only aromatic aldehyde that can be homopolymerized through chain-growth polymerization. The product, polyphthalaldehyde (PPA), is a brittle white solid, and, having a polyacetal main chain, presents the ability to depolymerize quite rapidly in the presence of an acid. This review highlights the unique polymerization chemistry of o-phthalaldehyde since its discovery over half a century ago, describing the different methods for the preparation of PPA and its derivatives, how the polymerization chemistry affects the structure and thermomechanical properties of the obtained PPA, and summarizes recent developments in PPA chemistry as a responsive material...
November 6, 2017: Macromolecular Rapid Communications
Marcin L Ślęczkowski, Egbert W Meijer, Anja R A Palmans
The synthesis and characterization of graft copolymers are reported based on linear poly(dimethyl siloxane) (PDMS) and chiral, pendant benzene-1,3,5-tricarboxamides (BTAs). The copolymers differ in degree of polymerization (DP) and BTA graft density. Characterization of the bulk materials at room temperature reveals that the BTAs aggregate in a helical fashion via threefold hydrogen-bond formation within the PDMS matrix. A significant degree of hydrogen bonding persists up to 180 °C, regardless of DP and BTA content...
November 6, 2017: Macromolecular Rapid Communications
Ya-Min Wang, Min Pan, Xiang-Yong Liang, Bang-Jing Li, Sheng Zhang
Electromagnetic wave absorption coatings can effectively minimize electromagnetic radiation and are widely used in the military and civil field. However, even small scratches on the coating can lead to a large decline of absorption ability and bring serious consequences. To enhance the lifetime of electromagnetic wave absorbing coating, a kind of self-healing electromagnetic wave absorbing coating is developed by introducing host-guest interactions between the absorbing fillers and polymer matrix. After being damaged, the cracks on this coating can be healed completely with the aid of small amounts of water...
November 2, 2017: Macromolecular Rapid Communications
Sascha Morlock, Jennifer M Kübel, Timo F Beskers, Bernhard Lendl, Manfred Wilhelm
The development of coupled techniques based on chemically sensitive detectors, such as FTIR or NMR spectrometers, for size exclusion chromatography (SEC) provides sophisticated methods for determining the molecular-weight-dependent chemical composition in polymers. However, the detection of rare functionalities such as end groups or branching points presents a challenge, especially for online coupled SEC detection, which is based on low-concentration chromatography. To address this issue, for the first time, an external cavity quantum cascade laser (EC-QCL) infrared spectrometer is coupled to an SEC...
November 2, 2017: Macromolecular Rapid Communications
Assala Al Samad, Audrey Bethry, Olga Janouskova, Jérémie Ciccione, Christiane Wenk, Jean-Luc Coll, Gilles Subra, Tomas Etrych, Fawaz El Omar, Youssef Bakkour, Jean Coudane, Benjamin Nottelet
Advanced drug delivery systems (DDS) are easily designed following a photoiterative strategy. Multifunctional polymers are obtained by coupling building blocks of interest to an alkynated poly(ε-caprolactone) (PCL) platform via an efficient thiol-yne photoaddition. Fine-tuning over the design is achieved, as illustrated with targeting and enzyme-responsive DDS.
November 2, 2017: Macromolecular Rapid Communications
Jie Cao, Xu Zhang, Canhui Lu, Yongyue Luo, Xinxing Zhang
Nowadays, it is still a challenge to prepare flexible sensors with great mechanical strength, stretchability, high sensitivities, and excellent self-healing (SH) abilities. Herein, a nanostructured supramolecular elastomer is reported with a dual noncovalent network of hydrogen bonding interactions and metal-ligand coordination. The resultant flexible sensor presents ultrafast (30 s), autonomous, and repeatable SH ability with high healing efficiency (80% after the 3rd healing process), as well as enhanced mechanical properties...
October 30, 2017: Macromolecular Rapid Communications
Qiujing Zhang, Sen Yu, Qian Wang, Qin Xiao, Yong Yue, Shijie Ren
Conjugated microporous polymers (CMPs) with strong fluorescence are great candidates for optoelectronic applications such as photocatalysis and chemical sensing. A series of novel fluorene-based conjugated microporous polymers (FCMPs) with different electronic structures are prepared by Yamamoto coupling reactions using rationally designed monomers. The FCMPs show a high degree of microporosity, decent specific surface areas, and variable fluorescence. FCMP3, which possesses a triazine knot in the network, exhibits the highest specific surface area of 489 m(2) g(-1) , the largest pore volume of 0...
October 30, 2017: Macromolecular Rapid Communications
Hai-Bo Zhao, Yu-Zhong Wang
Poly(ethylene terephthalate) (PET) is a fiber-forming polymer with the largest output and widest usage. Its flame retardation is well-achieved via a mechanism of promoting the melt dripping while ignited. However, the melt dripping leads to secondary damage and an immediate empyrosis during fire. How to address the contradiction between the flame retardation and the melt-dripping behavior of PET via an inherent flame-retardant approach becomes a real challenge. This feature article highlights the design and synthesis of novel PET-based copolyesters with flame-retardant and antidripping performance...
October 30, 2017: Macromolecular Rapid Communications
Han-Qing Wang, Huang Tan, Sun Hua, Zheng-Ying Liu, Wei Yang, Ming-Bo Yang
This article provides a novel and efficient method of "self-assembly/modification/dispersion" for the preparation of functionalized cellulose nanoparticles (CNPs) based on regenerated cellulose hydrogel (RCH). The process of the preparation of CNPs is simplified greatly, which contributes to broadening the utilization of CNPs. Under the given conditions, cellulose chains self-assemble into nanoparticles, which connect with each other to form strings and walls of nanoparticles inside RCH. Then, RCH acts as the hydrophilic precursor of the preparation of CNPs and is modified by oligo side chains to obtain functionalized RCH with imperfect cellulose II structures...
October 30, 2017: Macromolecular Rapid Communications
Wenkai Liu, Yun Zhao, Rong Wang, Jiehua Li, Jianshu Li, Feng Luo, Hong Tan, Qiang Fu
Shape-memory polymers are highly desirable in implant biomaterials for minimally invasive surgical procedures. However, most of them lack suitable transition temperature, mechanical properties, and biodegradability. Here, a series of shape-memory polyurethanes are synthesized by postcrosslinking in hard-segment domains using a flexible crosslinker. The materials used are all nontoxic and biodegradable. Through postcrosslinking of unsaturated linear polyurethanes with flexible and biodegradable crosslinker, the crosslinked polyurethanes (CPUs) show good mechanical properties, excellent shape-memory property, and repeatability...
October 30, 2017: Macromolecular Rapid Communications
Gilles B Desmet, Nils De Rybel, Paul H M Van Steenberge, Dagmar R D'hooge, Marie-Françoise Reyniers, Guy B Marin
Ab-initio-calculated rate coefficients for addition and fragmentation in reversible-addition fragmentation chain transfer (RAFT) polymerization of styrene with 2-cyano-2-propyl dodecyl trithiocarbonate initiated by azobisisobutyronitrile allow the reliable simulation of the experimentally observed conversion, number average chain length, and dispersity. The rate coefficient for addition of a macroradical Ri to the macroRAFT agent Ri X at 333 K (6.8 10(4) L mol(-1) s(-1) ) is significantly lower than to the initial RAFT agent R0 X (3...
October 27, 2017: Macromolecular Rapid Communications
Sonu Kumar, Stefanie Deike, Wolfgang H Binder
A synthetic strategy to efficiently prepare main-chain peptide-polymer conjugates probing their aggregation in solution is described. An in situ tandem reaction based on aminolysis/thio-bromo "click" reaction is performed to tether an amyloidogenic peptide fragment amyloid-β17-20 (Leu-Val-Phe-Phe (LVFF)) to the ω-chain end of poly(diethylene glycol methyl ether acrylate) (PDEGA), prepared via reversible addition fragmentation chain transfer polymerization. Structural confirmation of the constructed conjugates PDEGA-LVFF (Mn,SEC = 5600, Ð = 1...
October 27, 2017: Macromolecular Rapid Communications
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