Retracted: Effects of nanoparticles to the dynamical behavior of polymer chains in semidilute polymer solution: A dynamic light scattering study

The following article from the Journal of Polymer Science Part B: Polymer Physics: “Effects of nanoparticles to the dynamical behavior of polymer chains in semidilute polymer solution: A dynamic light scattering study,” by Mojammel H. Mondal, published online on 18 January 2011 in Wiley Online Library (onlinelibrary.wiley.com), has been retracted by agreement between the author, the journal Managing Editor, Dr. Victoria Cleave, and Wiley‐Blackwell. The retraction has been made as the research article was submitted without the author's PhD supervisor and principal investigator's knowledge or consent. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011     

Retracted: Determination of dextra–methylprednisolone conjugate with glycine linker in rat plasma and liver by high‐performance liquid chromatography and its application in pharmacokinetics

The following article from Biomedical Chromatography, Determination of dextra‐methylprednisolone conjugate with glycine linker in rat plasma and liver by high‐performance liquid chromatography and its application in pharmacokinetics by Shuang‐Qing Zhang and Reza Mehvar, published online on June 1^st 2009 in Wiley InterScience ( www.interscience.wiley.com ), has been retracted by agreement between the journal Editor in Chief, Dr Chang Kee Lim and John Wiley and Sons, Ltd. The retraction has been agreed as the research article was submitted without Dr. Mehvar's knowledge or consent.     

Structure–property relationships of polymer blend/clay nanocomposites: Compatibilized and noncompatibilized polystyrene/propylene/clay

Polymer blends represent an important class of materials in engineering applications. The incorporation of clay nanofiller may provide new opportunities for this type of materials to enhance their applications. This article reports on the effects of clay on the structure and properties of compatibilized and noncompatibilized polymer blends and presents a detailed process for quantitative analysis of the elastic moduli of polymer blend/clay nanocomposites, based on immiscible polystyrene/polypropylene (PS/PP) blends with or without maleated PP as the compatibilizer. The results show that in the noncompatibilized PS/PP/clay nanocomposite clay locates solely in the PS phase, whereas in the compatibilized nanocomposite clay disperses in both phases. The addition of clay to both polymer blends reduces the domain size significantly, modifies the crystallinity and improves the stiffness. The Mori–Tanaka and Christensen's models offer a reasonably good prediction of the elastic moduli of both types of nanocomposites. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012     

Reactions of Isocyanide Dihalides and their Derivatives

The readily obtainable isocyanide dichlorides can be used as starting materials for the preparation of many types of substances. Exchange reactions yield numerous derivatives of formic and carbonic acids, while heterocyclic products have been obtained by reaction with bifunctional partners. The present article deals not only with reactions that are known from the literature but also with the author's own work, some of which has not been published before.     

Retracted: Nanobubbles influence on BSA adsorption on mica surface

Retraction: The following article from the Surface and Interface Anlysis, 'Nanobubbles influence on BSA adsorption on mica surface' by Wu ZH, Zhang XH, Zhang XD, Li G, Sun J, Zhang Y, Li M and Hu J, published online on 1 September 2005 in Wiley InterScience ( www.interscience.com ) and in print Volume 37 Issue 10 pages 797‐801, 2005, has been retracted by agreement between the authors, the journal's Editor‐in‐Chief Professor John F. Watts and John Wiley & Sons, Ltd. The retraction has been agreed due to the article being subsequently published in Volume 38 Issue 6, pages 990‐995 of the journal as part of a Special Issue entitled 'Chinese‐German Forum on Fundamentals and Technological Perspectives of Nanoscience 26‐30 September 2004, Beijing, China.'     

Effects of Moisture on the Mechanical Properties of Microcrystalline Cellulose and the Mobility of the Water Molecules as Studied by the Hybrid Molecular Mechanics–Molecular Dynamics Simulation Method

A hybrid molecular mechanics–molecular dynamics simulation method has been performed to study the effects of moisture content on the mechanical properties of microcrystalline cellulose (MCC) and the mobility of the water molecules. The specific volume and diffusion coefficient of the water increase with increasing moisture content in the range studied of 1.8–25.5 w/w%, while the Young's modulus decreases. The simulation results are in close agreement with the published experimental data. Both the bound scission and free‐volume mechanisms contribute to the plasticization of MCC by water. The Voronoi volume increases with increasing moisture content. It is related to the free volume and the increase enhances the mobility of the water molecules and thus increases the coefficient of diffusion of the water. Moreover, with increasing moisture content, the hydrogen bonding per water molecule between MCC–water molecules decreases, thus increasing the water mobility and number of free water molecules. © 2019 The Authors. Journal of Polymer Science Part B: Polymer Physics published by Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019 , 57, 454–464     

Hybrid metal–polymer composites from functional block copolymers

The combination of metals and polymers in hybrid materials is a research area of great current interest. A number of methods for controlling the positioning of metallic species within polymer matrices on the nanometer scale have been developed. This highlight focuses on the use of functional block copolymers for the localization of metal species, especially nanoparticles, on the nanometer scale through block copolymer phase segregation. Research from the author's group on the use of alkyne‐functional block copolymers for the preparation of cobalt‐containing materials is discussed in this context. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 4323–4336, 2005     

Polymer research in industry: Quo vadis?

Even more than in the past, the polymer industry has to adapt its future strategy to a changing environment. This has, of course, also a great influence on industrial research and development activities. An attempt will be made to give answers on how industrial polymer research is going to live with this situation. The lecture is divided into 3 chapters: • Quo vadis Polymer Synthesis • Quo vadis Polymer Products • Effects on R & D-Strategy and -Organization Each chapter begins with general remarks and ends with some detailed examples. The chapter on future R & D-Strategy and -Organization also contains some comments on the future role of polymer research in academia. An extended Abstract of this lecture has been published as:     

1,4‐Diiodobenzene with –COO–TEMPO (TEMPO = 2,2,6,6‐tetramethylpiperidine‐1‐oxyl‐4‐yl) substituents at 2,5‐positions: synthesis and use as a monomer for new π‐conjugated polymers having nitroxyl radicals in side chains

The reaction of 2,5‐diiodo‐1,4‐benzenedicarbonyl chloride, C₆H₂I₂(COCl)₂‐p, with 4‐hydroxy‐2,2,6,6‐tetramethyl‐1‐piperidinyloxy (TEMPO‐ol) gave I–Ph(COO–TEMPO)₂–I, Monomer‐1. Pd‐catalyzed polycondensation of Monomer‐1 with Me₃Sn‐Th‐SnMe₃ (2,5‐bis(trimethylstannyl)thiophene) and Bu₃Sn–CH = CH–SnBu₃ (1,2‐bis‐(tributylstannyl)ethylene) gave the corresponding π‐conjugated polymers, Polymer‐1 and Polymer‐2, respectively. Monomer‐1 was converted to a diethynyl compound, H–C ≡ C–Ph(COO–TEMPO)₂–C ≡ C–H (Monomer‐1'), and Pd‐catalyzed polycondensation between Monomer‐1 and Monomer‐1' gave a π‐conjugated poly(arylene ethynylene) type polymer, Polymer‐3. According to the expansion of the π‐conjugation system by the polymerization, the UV–vis peaks of Monomer‐1 (λ_max = 323 nm) and Monomer‐1' (327 nm) are shifted to longer wavelengths (λ_max = 365 nm, 385 nm, and 396 nm for Polymer‐1, Polymer‐2, and Polymer‐3, respectively). Polymer‐1–Polymer‐3 showed ESR signals at about g = 2.01 with reasonable intensities. They are electrochemically active and showed a peak current anodic (oxidation) peak at about 0.9 V versus Ag/AgCl, which is reasonable for TEMPO polymers. Copyright © 2013 John Wiley & Sons, Ltd.     

Synthesis and properties of poly(arylene ether)s bearing sulfonic acid groups on pendant phenyl rings

Two kinds of new aromatic poly(arylene ether)s containing sulfonic acid groups were synthesized. Polymer 1 composed of tetraphenylphenylene ether and perfluorobiphenylene units was sulfonated with chlorosulfonic acid. Sulfonation took place only at the para position of the pendant phenyl rings. The average degree of sulfonation per repeating unit (m) was controlled from 1 to 4. Sulfonated polymer 2 with m = 3 was soluble in methanol and dimethyl sulfoxide and swelled in water. Incorporating bis(3,5‐dimethylphenyl)sulfone moieties into the sulfonated polymer imparts less methanol affinity. Polymers 4 with 30–65 mol % tetrakis(sulfophenyl)phenylene ether units has high decomposition temperatures above 300 °C, hydrophilicity, and good hydrolytic stability. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3211–3217, 2001     

Synthesis of well‐designed polymers carrying saccharide moieties via RAFT miniemulsion polymerization

Two hydrophobic vinyl saccharide monomers based on D ‐glucose and D ‐fructose were polymerized by employing the reversible addition‐fragmentation transfer (RAFT) miniemulsion polymerization technique to prepare well‐designed glycopolymers. Three dithiobenzoate‐RAFT agents [S?C(Ph)S? R], 1‐phenylethyl dithiobenzoate (PED), 2‐phenylprop‐2‐yl dithiobenzoate (PPD), and 2‐cyanoprop‐2‐yl dithiobenzoate (CPD), were used to control the growth of polymer chains. The best results were obtained in the presence of the PPD‐RAFT agent and the formed polymers have polydispersity index's (PDI) lower than 1.15. Under adequate miniemulsion polymerization conditions, a glycopolymer with PDI of 1.1 and molecular weight of 5 × 10⁴ g/mol has been successfully synthesized in a short reaction time of 100 min. Furthermore, some block copolymers containing saccharide segment with butyl or methyl methacrylate were prepared. Copyright © 2007 John Wiley & Sons, Ltd.     

Crown Ethers and Phase Transfer Catalysis in Polymer Chemistry

Abstract

This paper is the first half of a two part review on the applications of crown ethers, cryptands, glymes and various onium ion salts to polymer chemistry. Part 1 surveys the use of these phase transfer catalysts (PTC's) in the synthesis and modification of macromolecules. Applications to ring-opening and vinyl polymerizations generally have involved solubilization and activation by PTC's of organic and inorganic salts which serve as anionic initiators. Change in the polymerization rates, polymer yields and product microstructure often resulted from association of the PTC with the active chain end.

Polymer modification and functionalization reactions have been enhanced by the use of PTC's. Macromolecular substrates have included both soluble and insoluble polymers, although the most popular have been the readily-available Merrifield resins. Generally these two-phase reactions have involved polymer solutions interacting with insoluble reagents or insoluble polymers reacting with the reagent solution. Some of the groups incorporated have been thiols, nitriles, carboxylic acids, esters, and crown ether analogs themselves. Most of this work has aimed at synthesis of polymer derivatives which can serve as chelating agents, catalysts and reagents in subsequent reactions. In almost all cases described, phase transfer catalysis offers definate advantages in selectivity and yield over conventional methods. The outline below gives the general subject areas of both Part 1 and Part 2; the latter will be published shortly.     

Solution‐crystallization and related phenomena in 9,9‐dialkyl‐fluorene polymers. I. Crystalline polymer‐solvent compound formation for poly(9,9‐dioctylfluorene)

Polymer‐solvent compound formation, occurring via co‐crystallization of polymer chains and selected small‐molecular species, is demonstrated for the conjugated polymer poly(9,9‐dioctylfluorene) (PFO) and a range of organic solvents. The resulting crystallization and gelation processes in PFO solutions are studied by differential scanning calorimetry, with X‐ray diffraction providing additional information on the resulting microstructure. It is shown that PFO‐solvent compounds comprise an ultra‐regular molecular‐level arrangement of the semiconducting polymer host and small‐molecular solvent guest. Crystals form following adoption of the planar‐zigzag β‐phase chain conformation, which, due to its geometry, creates periodic cavities that accommodate the ordered inclusion of solvent molecules of matching volume. The findings are formalized in terms of nonequilibrium temperature–composition phase diagrams. The potential applications of these compounds and the new functionalities that they might enable are also discussed. © 2015 The Authors. Journal of Polymer Science Part B: Polymer Physics published by Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 1481–1491     

Retracted: EMI shielding effectiveness of expanded graphite and reduced graphene oxide

Retraction: Gairola, SP, Gairola, P, Shah, SK, Gupta, R. EMI shielding effectiveness of expanded graphite and reduced graphene oxide. J. Chin. Chem. Soc. 2018. https://doi.org/10.1002/jccs.201800189 . The above article, published online on 1 October 2018 in Wiley Online Library ( https://onlinelibrary.wiley.com ), has been retracted by agreement between the corresponding author, the journal's Editor‐in‐Chief, Dr. Yu‐Tai Tao, the Chemical Society Located in Taipei, and Wiley‐VCH Verlag GmbH & Co. KGaA. The retraction has been agreed due to several images across Figures 1, 2 and 3 within the article having been duplicated from other publications. The corresponding author apologizes for the inconvenience caused.     

My life with polymer science

This article describes the scientific investigations and accomplishments in the life of the author. After a dissertation on steroids, several years were spent on alkaloids and research on heterocyclic compounds. Much of the author's career was devoted to research on aldehyde polymerization, the discovery of the polymerization of higher aldehydes and their isotactic polymers, and haloaldehyde polymerization. The latter led to our work on the ceiling temperature of polymerization, on new polymerization techniques [involving the ceiling temperature and the concept of macromolecular asymmetry (polymer helicity)], and the genesis of chloral polymerization. Another important period was devoted to functional polymers, polymeric stabilizers, and polymeric drugs. Other research activities included studies of unusual polymers, head-to-head polymers, spacer groups in polymers, and oriental lacquers. Attention was also paid to the use of novel and unusual polymer intermediates, polymerization under extreme conditions and the preparation and behavior of uncommon polymer structures. Finally, it was recognized that macromolecules can be categorized with increasing frequency as polymers with broad and narrow molecular weight distributions and uniform polymers. The ultimate unity is isotopically pure uniform polymers, single macromolecular species. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 795–818, 2004     

Retracted: Prediction of posttranslational modification sites from sequences with kernel methods

The following article from the Journal of Computational Chemistry, “Prediction of Posttranslational Modification Sites from Sequences with Kernel Methods,” by Xiaobo Wang, Yongcui Wang, Yingjie Tian, Xiaojian Shao, Ling‐Yun Wu, and Naiyang Deng, published online on 21 April 2010 in Wiley Online Library (wileyonlinelibrary.com), DOI: 10.1002.jcc.21526, has been retracted by agreement between the authors, the journal's editors, and Wiley Periodicals, Inc. The retraction has been agreed because a computational error produced results that led the authors to overstate the level of performance of their computing model.     

Polyolefin analysis by single‐step crystallization fractionation

Temperature rising elution fractionation (TREF) fractionates polymer chains with respect to their crystallizability, independently of molecular weight effects. In order to achieve a good fractionation, TREF requires a time‐consuming polymer deposition step over an inert support before the elution step. A single‐step crystallization fractionation method has been developed recently,^1,2 Crystallization Analysis Fractionation (CRYSTAF), in which the chemical composition (or short chain branching) distribution of olefin copolymers can be measured by monitoring on‐line polymer concentration in solution at decreasing temperatures. For the present experimental investigation, a CRYSTAF‐prototype has been assembled and used to fractionate several linear low‐density polyethylene (LLDPE) samples. These results were compared to the ones measured by the commercial CRYSTAF apparatus from Polymer ChAR. Additionally, CRYSTAF results from Polymer ChAR were compared to analytical TREF results. © 1999 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 37: 539–552, 1999     

Dependence on material choice of degradation of organic solar cells following exposure to humid air

Electron microscopy has been used to study the degradation of organic solar cells when exposed to humid air. Devices with various different combinations of commonly used organic solar cell hole transport layers and cathode materials have been investigated. In this way the ingress of water and the effect it has on devices could be studied. It was found that calcium and aluminum in the cathode both react with water, causing voids and delamination within the device. The use of poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) was found to increase the degradation by easing water ingress into the device. Replacing these materials removed these degradation features. © 2015 The Authors. Journal of Polymer Science Part B: Polymer Physics published by Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016, 54, 216–224