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Inside Front Cover: polymer–Silicon Flexible Structures for Fast Chemical Vapor Detection (Adv. Mater. 23/2007)

Advanced Materials 2007年第23期19卷

作者： S. Singamaneni M. E. McConney M. C. LeMieux H. Jiang J. O. Enlow T. J. Bunning R. R. Naik V. V. Tsukruk School of Materials Science and Engineering and School of Polymer Textile and Fiber Engineering Georgia Institute of Technology Atlanta GA 30332 (USA) Chemical Engineering Department Stanford University Stanford CA 94305 (USA) Materials and Manufacturing Directorate Air Force Research Laboratory Wright‐Patterson Air Force Base OH 45433

Vladimir Tsukruk and co‐workers demonstrate on p. 4248 the application of plasma‐polymerized organic/silicon bimaterial structures as highly sensitive and agile chemical sensors. Owing to their unique nanoscale topology, highly crosslinked structure, and precise choice of the precursors, polymer films coated on microcantilevers exhibited record sensitivity to water vapor and other volatile organic compounds in conjunction with fast response times. The inside cover image by Brian Schrank shows the bimaterial structure deflection in the presence of a stimuli vapor.

关键词： Coatings Plasma polymerization polymer composites Sensors Silicon

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Structure development and physical properties achieved in the drawing and/or annealing of PEN fibers

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Journal of polymer science 2000年第11期38卷

作者： Gang Wu Ming Liu Xiaoning Li John A. Cuculo College of Material Science and Engineering Beijing University of Chemical Technology Beijing 100029 China Department of Fibrous Material Engineering Beijing Institute of Clothing Technology Beijing 100029 China Fiber & Polymer Science Program College of Textiles North Carolina State University Raleigh North Carolina 27695

As-spun poly(ethylene-2,6-naphthalate) (PEN) fibers (i.e., precursors) prepared from high molecular weight polymer were drawn and/or annealed under various conditions. Structure and property variations taking place during the treatment process were followed via wide-angle X-ray scattering (WAXS), small-angle X-ray scattering, differential scanning calorimetry (DSC), and mechanical testing. Both the WAXS and DSC measurements of the cold-drawn samples stretched from a low-speed-spun amorphous fiber indicate that strain-induced crystallization can occur at a temperature below the glass-transition temperature and that the resultant crystal is in the α-form modification. In contrast, when the same precursor was subjected to constrained annealing, its amorphous characteristics remained unchanged even though the annealing was performed at 200 °C. These results may imply that the application of stretching stress is more important than elevated temperatures in producing α-form crystallization. The crystalline structure of the hot-drawn samples depends significantly on the morphology of the precursor fibers. When the precursor was wound at a very low speed and in a predominantly amorphous state, hot drawing induced the formation of crystals that were apparently pure α-form modification. For the β-form crystallized precursors wound at higher speeds, a partial crystalline transition from the β form to the α form was observed during the hot drawing. In contrast with the mechanical properties of the as-spun fibers, those of the hot-drawn products are not improved remarkably because the draw ratio is extremely limited for most as-spun fibers in which an oriented crystalline structure has already formed. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 1424–1435, 2000

关键词： poly(ethylene-2,6-naphthalate) fiber drawing annealing structural change crystalline transition

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Monomer and Excimer Emission in a Conformational and Stacking-Adaptable Molecular System

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Angewandte Chemie 2022年第4期135卷

作者： Xueru Shan Weijie Chi Hengbing Jiang Zhangyuan Luo Prof. Cheng Qian Prof. Hongwei Wu Prof. Yanli Zhao State Key Laboratory for Modification of Chemical Fiber and Polymer Materials Key Lab of Science and Technology of Eco-Textile Ministry of Education College of Chemistry and Chemical Engineering Donghua University Shanghai 201620 China Department of Chemistry School of Science Hainan University Haikou 570228 China School of Chemistry Chemical Engineering and Biotechnology Nanyang Technological University Singapore 637371 Singapore

A design strategy that combines molecular conformation, alkyl chain length, and charge-transfer effects has been developed to obtain conformational and stacking-adaptable donor-acceptor-π type molecules for precisely regulating the monomer and excimer emission in a single luminous platform under different environments. These fluorophores can exhibit bright monomer emissions when they are in the dispersed state based on their planar conformation. However, when the luminous molecules with short alkyl side chains are in the crystalline state, their molecular conformation can become distorted, further inducing strong intermolecular interactions and staggered π-π stacking for bright excimer emission. More importantly, their dispersed and aggregated states can be reversibly regulated in a phase-change fatty acid matrix, to achieve temperature-responsive fluorescence for temperature monitoring and advanced information encryption.

关键词： Aggregated State Conformational Flexibility Dispersed State Monomer-Excimer Fluorescence Temperature Responsivity

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Inside Front Cover: Field‐Driven Biofunctionalization of polymer fiber Surfaces during Electrospinning (Adv. Mater. 1/2007)

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Advanced Materials 2007年第1期19卷

作者： X.‐Y. Sun R. Shankar H. G. Börner T. K. Ghosh R. J. Spontak Department of Chemical & Biomolecular Engineering North Carolina State University Raleigh NC 27695 USA Department of Materials Science & Engineering North Carolina State University Raleigh NC 27695 USA Fiber & Polymer Science Program North Carolina State University Raleigh NC 27695 USA Department of Colloid Chemistry Max‐Planck Institute of Colloids & Interfaces 14424 Potsdam Germany

Surface‐biofunctionalized synthetic polymer fibers composed of a fiber‐forming host polymer and an oligopeptide conjugate can be prepared from electrospinning, report Spontak and co‐workers on p. 87. The conjugate consists of a polypeptide segment and a polymer block that is compatible with the host polymer. Because the more polarizable peptide segment migrates to the surface during electrospinning, peptide surface‐enrichment is achieved in a single step without further treatment.

关键词： Biocompatible materials Block copolymers Electrospinning fibers Peptides Poly(ethylene oxide) Surface functionalization

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Vibration-Regulated Multi-State Long-Lived Emission from Star-Shaped Molecules

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Angewandte Chemie 2022年第48期134卷

作者： Yiran Li Dr. Glib V. Baryshnikov Dr. Farhan Siddique Dr. Peng Wei Prof. Hongwei Wu Prof. Tao Yi State Key Laboratory for Modification of Chemical Fiber and Polymer Materials Key Lab of Science and Technology of Eco-Textile Ministry of Education College of Chemistry and Chemical Engineering Donghua University Shanghai 201620 China State Key Laboratory of Molecular Engineering of Polymers Department of Chemistry Fudan University Shanghai 200433 China Laboratory of Organic Electronics Department of Science and Technology Linköping University 60174 Norrköping Sweden

How to utilize molecular vibration to tune triplet-involved emissions in multiple states is highly challenging. Here, star-shaped triphenylamine derivatives have been employed as model systems to understand how molecular vibration affects thermally activated delayed fluorescence (TADF) and room temperature phosphorescence (RTP) emissions in multiple states. Nonplanar, star-shaped conformations allow molecules to generate appropriate vibrations in the solution state, facilitating vibronic coupling between their T 1 and T 2 states to generate effective TADF. More importantly, a relatively dispersed state can allow the molecules to efficiently vibrate in the solid state, and a crystalline environment further promotes a more efficient TADF. Lastly, by suppressing molecular vibration to inhibit the TADF, ultra-long RTP was observed upon doping these molecules into polymers. These molecules can be used in information encryption and storage as well as bioimaging.

关键词： Anti-Counterfeiting Bioimaging Room Temperature Phosphorescence Thermal Activation Delayed Fluorescence Vibronic Coupling

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Amino acid-based bioanalogous polymers. Synthesis, and study of regular poly(ester amide)s based on bis(α-amino acid) α,ω-alkylene diesters, and aliphatic dicarboxylic acids

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Journal of polymer science 2000年第4期37卷

作者： R. Katsarava V. Beridze N. Arabuli D. Kharadze C. C. Chu C. Y. Won Centre for Medical Polymers and Biomaterials of Ministry of Health and Institute of Molecular Biology & Biophysics of Georgian Academy of Sciences P.O. Box 24 380079 Tbilisi-79 Georgia Fiber and Polymer Science Program Department of Textiles & Apparel & Biomedical Engineering Program Cornell University Ithaca New York 14853-4401

The purpose of this research was to synthesize new regular poly(ester amide)s (PEAs) consisting of nontoxic building blocks like hydrophobic α-amino acids, α,ω-diols, and aliphatic dicarboxylic acids, and to examine the effects of the structure of these building block components on some physico-chemical and biochemical properties of the polymers. PEAs were prepared by solution polycondensation of di- p -toluenesulfonic acid salts of bis-(α-amino acid) α,ω-alkylene diesters and di- p -nitrophenyl esters of diacids. Optimal conditions of this reaction have been studied. High molecular weight PEAs ( M w = 24,000–167,000) with narrow polydispersity ( M w / M n = 1.20–1.81) were prepared under the optimal reaction conditions and exhibited excellent film-forming properties. PEAs obtained are mostly amorphous materials with T g from 11 to 59°C. α-Chymotrypsin catalyzed in vitro hydrolysis of these new PEA substrates was studied to assess the effect of the building blocks of these new polymers on their biodegradation properties. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 391–407, 1999

关键词： α-amino acids biodegradable polymers regular poly(ester amide)s α-chymotrypsinolysis

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Macromol. Rapid Commun. 22/2016

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Macromolecular Rapid Communications 2016年第22期37卷

作者： Syamal S. Tallury Behnam Pourdeyhimi Melissa A. Pasquinelli Richard J. Spontak Fiber & Polymer Science Program North Carolina State University Raleigh NC 27695 USA Department of Materials Science & Engineering North Carolina State University Raleigh NC 27695 USA The Nonwovens Institute North Carolina State University Raleigh NC 27695 USA Department of Chemical & Biomolecular Engineering North Carolina State University Raleigh NC 27695 USA

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Lithium-Ion Batteries: Excimer Ultraviolet-Irradiated Carbon Nanofibers as Advanced Anodes for Long Cycle Life Lithium-Ion Batteries (Small 38/2016)

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Small 2016年第38期12卷

作者： Zhen Shen Yi Hu Yanli Chen Renzhong Chen Xia He Lei Geng Xiangwu Zhang Keshi Wu Key Laboratory of Advanced Textile Materials and Manufacturing Technology Ministry of Education Zhejiang Sci-Tech University Hangzhou 310018 P. R. China Engineering Research Center for Eco-Dying & Finishing of Textiles Ministry of Education Zhejiang Sci-Tech University Hangzhou 310018 P. R. China Dyeing and Finishing Institute of Zhejiang Sci-Tech University Zhejiang Sci-Tech University Hangzhou 310018 P. R. China Fiber and Polymer Science Program Department of Textile Engineering Chemistry and Science North Carolina State University Raleigh NC 27695–8301 USA

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Crosslinking of chitosan fibers with dialdehydes: Proposal of a new reaction mechanism

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Journal of polymer science 1999年第11期37卷

作者： Jonathan Z. Knaul Samuel M. Hudson Katherine A. M. Creber Department of Chemistry and Chemical Engineering Royal Military College PO Box 17000 Station Forces Kingston Ontario K7K 7B4 Canada Fiber and Polymer Science Program Box 8301 Centennial Campus North Carolina State University Raleigh North Carolina 27695-8301

A highly deacetylated chitosan from shrimp with a degree of deacetylation of 95.28 ± 3.03% was prepared and spun into a monofilament fiber using a solution of 4% (w/v) chitosan in 4% (v/v) aqueous acetic acid. Samples of the spun fibers were immersed in aqueous solutions containing glutaraldehyde and glyoxal, and subsequently washed and dried. When the concentration of crosslinking agent was varied at room temperature over a constant time of 1 h, dry mechanical properties improved up to a point after which increasing concentrations resulted in degradation. Immersion time was also varied between 1 and 60 min at 25.8°C, and temperature was varied between 25.8 and 70.0°C, at fixed concentrations of both glyoxal and glutaraldehyde. It was demonstrated that mechanical improvements might be rendered at higher temperatures over lesser times. However, it was also shown that at higher temperatures, fiber mechanical properties would begin to diminish. Chitosan films were subjected to similar treatments in aqueous crosslinking solutions. Fourier transform infrared data (FTIR) on the films suggest that some interaction is occurring between the glutaraldehyde or glyoxal and the amine group on the chitosan backbone. © 1999 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 37: 1079–1094, 1999

关键词： chitosan fiber crosslinking mechanical films FTIR wet spinning

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Publisher's Note: “Communication: Molecular-level insights into asymmetric triblock copolymers: Network and phase development” [J. Chem. Phys. 141, 121103 (2014)]

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The Journal of Chemical Physics 2014年第16期141卷

作者： Syamal S. Tallury Kenneth P. Mineart Sebastian Woloszczuk David N. Williams Russell B. Thompson Melissa A. Pasquinelli Michal Banaszak Richard J. Spontak 1Department of Materials Science and Engineering North Carolina State University Raleigh North Carolina 27695 USA 2Fiber and Polymer Science Program North Carolina State University Raleigh North Carolina 27695 USA 3Department of Chemical and Biomolecular Engineering North Carolina State University Raleigh North Carolina 27695 USA 4Faculty of Physics Adam Mickiewicz University 61-614 Poznan Poland 5Department of Physics and Astronomy and Waterloo Institute for Nanotechnology University of Waterloo Waterloo Ontario N2L 3G1 Canada

This article was originally published online on 29 September 2014 with an error in the journal title of Ref. 36. The corrected reference appears below:

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