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Macromolecular Rapid Communications

Chenxiao Xiong, Meiran Xie, Ruyi Sun
The synthesis and characterization of a linear supramolecular polymer formed by dual host-guest recognitions is presented. The polymer linked by the orthogonal interactions of azobenzene with β-cyclodextrin and methyl viologen with sulfonatocalix[4]arene is constructed, and the morphology change along with the formation and vanishment of host-guest interaction is investigated. The reversible disassembly-reassembly of the polymer induced by light and the redox process are monitored by UV-vis and cyclic voltammetry, respectively...
August 16, 2017: Macromolecular Rapid Communications
Jennifer L Poole, Scott Donahue, David Wilson, Yuk Mun Li, Qi Zhang, Yibei Gu, Rachel Ferebee, Zhao Lu, Rachel Mika Dorin, Lawrence F Hancock, Larry Takiff, Ilhem F Hakem, Michael R Bockstaller, Ulrich Wiesner, Jeremy Walker
The functionalization with phosphotriesterase of poly(isoprene-b-styrene-b-4-vinylpyridine)-based nanoporous membranes fabricated by self-assembly and nonsolvent induced phase separation (SNIPS) is shown to enable dynamically responsive membranes capable of substrate-specific and localized gating response. Integration of the SNIPS process with macroporous nylon support layers yields mechanically robust textile-type films with high moisture vapor transport rates that display rapid and local order-of-magnitude modulation of permeability...
August 15, 2017: Macromolecular Rapid Communications
Yang Zheng, Yucheng Huang, Brian C Benicewicz
The preparation of well-defined block copolymers using controlled radical polymerization depends on the proper order of monomer addition. The reversed order of monomer addition results in a mixture of block copolymer and homopolymer and thus has typically been avoided. In this paper, the low blocking efficiency of reversed monomer addition order is utilized in combination with surface initiated reversible addition-fragmentation chain-transfer polymerization to establish a facile procedure toward mixed polymer brush grafted nanoparticles SiO2 -g-(PS (polystyrene), PS-b-PMAA (polymethacrylic acid))...
August 14, 2017: Macromolecular Rapid Communications
Anne Fuhrmann, Kevin Broi, Stefan Hecht
To reduce the environmental footprint of the modern society, it is desirable to elongate the lifetime of consumer products, for example by implementing healable coatings and protective layers. However, since most healing processes carried out by heat or light suffer from material degradation, improving the robustness and integrity of healable materials is of tremendous importance to prolong their lifetime. In recent work, a prototype is created of a dynamic covalent polymer network, whose thermal healing ability can be switched "on" and "off" by light to provide a means to locally control repair of a damaged coating...
August 10, 2017: Macromolecular Rapid Communications
Milena Nadgorny, Dillon T Gentekos, Zeyun Xiao, S Parker Singleton, Brett P Fors, Luke A Connal
Molecular weight and dispersity (Ð) influence physical and rheological properties of polymers, which are of significant importance in polymer processing technologies. However, these parameters provide only partial information about the precise composition of polymers, which is reflected by the shape and symmetry of molecular weight distribution (MWD). In this work, the effect of MWD symmetry on thermal and rheological properties of polymers with identical molecular weights and Ð is demonstrated. Remarkably, when the MWD is skewed to higher molecular weight, a higher glass transition temperature (Tg ), increased stiffness, increased thermal stability, and higher apparent viscosities are observed...
August 10, 2017: Macromolecular Rapid Communications
Yu Dai, Xiaojin Zhang, Fan Xia
Click chemistry, one of the most important methods in conjugation, plays an extremely significant role in the synthesis of functional aliphatic polycarbonates, which are a group of biodegradable polymers containing carbonate bonds in their main chains. To date, more than 75 articles have been reported on the topic of click chemistry in functional aliphatic polycarbonates. However, these efforts have not yet been highlighted. Six categories of click reactions (alkyne-azide reaction, thiol-ene reaction, Michael addition, epoxy-amine/thiol reaction, Diels-Alder reaction, and imine formation) that have been afforded for further post-polymerization modification of polycarbonates are reviewed...
August 10, 2017: Macromolecular Rapid Communications
Hao Xing, Zhengtao Li, Zi Liang Wu, Feihe Huang
A new strategy is introduced to prepare an adaptive polymer gel that has a unique adaptability in response to environmental stimuli. This gel is prepared by the thiol-ene "click" reaction between a bisvinyl [2]catenane and a poly(ethylene glycol) derivative containing multiple thiol groups. The catenane crosslinker is responsive to external stimuli due to the existence of intercomponent hydrogen bonding (IHB). The strong IHB restricts the rotation and movement of the crosslinker, giving it a rigid feature; however, the crosslinker becomes flexible when the IHB is destroyed...
August 10, 2017: Macromolecular Rapid Communications
Shaojian Lin, Jiaojiao Shang, Xiaoxiao Zhang, Patrick Theato
A well-defined amphiphilic triblock copolymer, poly[(ethylene glycol)methyl ether]-block-poly(N,N-dimethylamino ethyl methacrylate-co-2,2,2-trifluoroethyl methacrylate)-block-poly(4-(4-methoxy-phenylazo)phenoxy methacrylate) (PEG-b-P(DMAEMA-co-TFEMA)-b-PMEPPMA), is successfully synthesized by stepwise atom transfer radical polymerization. Owing to its amphiphilic nature, PEG-b-P(DMAEMA-co-TFEMA)-b-PMEPPMA can self-assemble into vesicles in aqueous solution and exhibits a reversible triple-responsive behavior toward CO2 , O2 , and light stimuli...
August 9, 2017: Macromolecular Rapid Communications
Byungjin Koo, Timothy M Swager
Commercial dyes are extensively utilized to stain specific phases for the visualization applications in emulsions and bioimaging. In general, dyes emit only one specific fluorescence signal and thus, in order to stain various phases and/or interfaces, one needs to incorporate multiple dyes and carefully consider their compatibility to avoid undesirable interactions with each other and with the components in the system. Herein, surfactant-type, perylene-endcapped fluorescent conjugated polymers that exhibit two different emissions are reported, which are cyan in water and red at oil-water interfaces...
August 3, 2017: Macromolecular Rapid Communications
Georgi Stoychev, Mir Jalil Razavi, Xianqiao Wang, Leonid Ionov
There exist many methods for processing of materials: extrusion, injection molding, fibers spinning, 3D printing, to name a few. In most cases, materials with a static, fixed shape are produced. However, numerous advanced applications require customized elements with reconfigurable shape. The few available techniques capable of overcoming this problem are expensive and/or time-consuming. Here, the use of one of the most ancient technologies for structuring, embroidering, is proposed to generate sophisticated patterns of active materials, and, in this way, to achieve complex actuation...
July 31, 2017: Macromolecular Rapid Communications
Heyu Shen, Hongwei Ma, Pibo Liu, Wei Huang, Li Han, Chao Li, Yang Li
By combining living anionic polymerization and the highly efficient Ugi four-component reaction (Ugi-4CR), in-chain, multicomponent, functionalized polymers are facilely synthesized with efficient conversation and abundant functionality. l-[4-[N,N-Bis(trimethylsilyl)-amino]phenyl]-l-phenylethylene, which is redefined as Ugi-DPE, is anionically copolymerized to synthesize the well-defined in-chain, multi-amino functionalized polystyrene (P(St/DPE-NH2 )), the backbone for the Ugi-4CR, via hydrolysis of the copolymerization (P(St/Ugi-DPE))...
July 31, 2017: Macromolecular Rapid Communications
Chenhao Yao, Jing Zhang, Ming Cheng, Qiang Sun, Yi Pan, Juli Jiang, Leyong Wang
By linking BMP32C10 and DB24C8 motifs together, a four-armed cryptand 1 is synthesized successfully, in which BMP32C10 motif can bind paraquat 2 while DB24C8 motif can complex dibenzylammonium salt 3 in spite of the electrostatic repulsion between guests 2 and 3. The base/acid-responsive supramolecular polymer is constructed further via two kinds of host-guest interactions between cryptand 1 and two homoditopic paraquat 4 and dibenzylammonium salt 5 similar to guests 2 and 3.
July 31, 2017: Macromolecular Rapid Communications
Anemar Bruno Kanj, Kai Müller, Lars Heinke
Metal-organic frameworks (MOFs) are nanoporous, crystalline hybrid materials, which enable various functionalities by incorporating functional organic molecules. By using organic linker molecules that possess photoswitchable azobenzene side groups, the remote control over certain properties was introduced to MOFs. Different MOF materials in the form of powders and thin films have been used to demonstrate the photoswitching. The applications of these stimuli-responsive nanoporous solids range from switching the adsorption capacity of various gases over remote-controlled release of guest molecules to continuously tunable membrane separation of molecular mixtures...
July 31, 2017: Macromolecular Rapid Communications
Zehuan Huang, Bo Qin, Linghui Chen, Jiang-Fei Xu, Charl F J Faul, Xi Zhang
Supramolecular polymers have attracted plenty of interest in the scientific community; however, developing controllable methods of supramolecular polymerization remains a serious challenge. This article reviews some recent developments of methods for supramolecular polymerization from controllable fabrication to living polymerization. Three facile methods with general applicability for controllable fabrication of supramolecular polymers have been established recently: the first method is a self-sorting approach by manipulating ring-chain equilibrium based on noncovalent control over rigidity of monomers; the second is covalent polymerization from supramonomers formed by noncovalent interactions; and the third is supramolecular interfacial polymerization...
July 28, 2017: Macromolecular Rapid Communications
Tzu-Hsuan Chang, Shisheng Xiong, Chi-Chun Liu, Dong Liu, Paul F Nealey, Zhenqiang Ma
The direct self-assembly of cylinder-forming poly(styrene-block-methyl-methacrylate) (PS-b-PMMA) block copolymer is successfully assembled into two orientations, according to the underlying guiding pattern in different areas. Lying-down and perpendicular cylinders are formed, respectively, depending on the design of chemical pattern: sparse line/space pattern or hexagonal dot array. The first chemical pattern composed of prepatterned cross-linked polystyrene (XPS) line/space structure has a period (LS ) equal to twice the intercylinder period of the block copolymer (L0 )...
July 27, 2017: Macromolecular Rapid Communications
Ruiyang Zhao, Jishu Han, Mei Huang, Fusheng Liu, Lei Wang, Yuguang Ma
Stable controlled release system, conjugated microporous polymers (CMPs) with stimuli-responsive properties can be ideal structures because their 3D microporous matrix structure and possible stimulated response provide inherent switchable acceptor sites to capture and release guest molecules. Herein, the in situ electrochemical deposition of precursors (DTCzAzo) is utilized to construct highly crosslinked photoresponsive CMP films, which can reversibly undergo the trans-to-cis isomerization alternately with irradiation by 355 and 480 nm laser beams...
July 27, 2017: Macromolecular Rapid Communications
Anton H Hofman, Mehedi Reza, Janne Ruokolainen, Gerrit Ten Brinke, Katja Loos
Involving supramolecular chemistry in self-assembling block copolymer systems enables design of complex macromolecular architectures that, in turn, could lead to complex phase behavior. It is an elegant route, as complicated and sensitive synthesis techniques can be avoided. Highly grafted double-comb diblock copolymers based on symmetric double hydrogen bond accepting poly(4-vinylpyridine)-block-poly(N-acryloylpiperidine) diblock copolymers and donating 3-nonadecylphenol amphiphiles are realized and studied systematically by changing the molecular weight of the copolymer...
July 27, 2017: Macromolecular Rapid Communications
Shiyu Long, Fei Lin, Changguang Yao, Dongmei Cui
The polymerization of a new polar diene-based monomer 2-(2-methylidenebut-3-enyl)furan (MBEF) without masking is achieved by using the bis(phosphino)carbazoleide-ligated yttrium (Y) alkyl complex upon the activation of [Ph3 C][B(C6 F5 )4 ]. Under mild conditions, the polymerizations under the monomer-to-Y ratios ranging from 100:1 to 500:1 perform fluently in high yields. The afforded polydienes bearing pendant terminal furan groups have high cis-1,4-regularity up to 98.6% and molecular weights close to the theoretic values and narrow polymer dispersity index(PDI) (1...
July 27, 2017: Macromolecular Rapid Communications
Kimio Sumaru, Toshiyuki Takagi, Taku Satoh, Toshiyuki Kanamori
The photo- and thermoresponse of poly(N-isopropylacrylamide) (pNIPAAm) functionalized with spiropyran chromophore is examined with respect to the influence of molecular recognition by cyclodextrin (CD). Characterization in aqueous solutions of spiropyran-functionalized poly(N,N-dimethylacrylamide) under coexistence of α-, β-, or γ-CD reveals that β-CD selectively includes the ring-closing isomer of the chromophore, which is dominant under light irradiation, while no inclusion is observed for the protonated ring-opening isomer, which is dominant in the dark before irradiation...
July 26, 2017: Macromolecular Rapid Communications
Zhi-Huang Zhang, Chen-Yang Qiao, Jian Zhang, Wen-Ming Zhang, Jun Yin, Zong-Quan Wu
Here, the fabrication of unimolecular micelles functionalized with helical polymeric chains as a chiral nucleating agent in enantioselective crystallization is reported. Starting from a fractionated hyperbranched polyester (Boltorn H30), the ring-opening polymerization of l-lactic acid (LLA) and subsequent terminal-group modification affords the alkyne-Pd(II)-anchored hyperbranched macroinitiator (H30-PLLA-Pd). By taking advantage of a Pd(II)-catalyzed living polymerization of chiral pendant modified l- or d-phenyl isocyanide (PI) monomers, well-defined chiral unimolecular micelles (H30-PLLA-PPI) grafted with radiating helical PPI coronas of one predominant screw sense are obtained...
July 25, 2017: Macromolecular Rapid Communications
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