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1.
We report a new type of step‐growth radical addition‐coupling polymerization (RACP) involving consecutive addition of carbon‐centered radical derived from α,α′‐dibromo dibasic ester to NO double bond of C‐nitroso compound followed by cross‐coupling of carbon‐centered radical and in situ formed nitroxyl radical, which produces alternating copolymers with high molecular weight and unimodal molecular weight distribution from saturated and unsaturated monomers.
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Summary: Nanocomposites were formulated by curing a sonicated mixture of epoxy resin, C18 clay, and acrylic rubber dispersants. At 5.5 phr (parts per hundred) organoclay loading and a rubber concentration of 15 phr, the tensile‐failure strain of the nanocomposite was found to be higher than that of epoxy nanocomposite, rubber‐dispersed epoxy, and pristine epoxy. A plausible mechanism for improvement of the failure strain of nanocomposites is proposed.
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Andrew P. Vogt Thomas Tischer Udo Geckle Alexandra M. Greiner Vanessa Trouillet Michael Kaupp Leonie Barner Thorsten Hofe Christopher Barner‐Kowollik 《Macromolecular rapid communications》2013,34(11):916-921
Intrinsically glucoside‐based microspheres are prepared in olive oil via a water in oil inverse suspension polymerization. The microspheres are characterized by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) microscopy, and X‐ray photoelectron spectroscopy (XPS), evidencing the intrinsic glucose character of the spheres. A novel boronic acid fluorescent molecule was subsequently conjugated to the microspheres in an aqueous environment, exhibiting the spatial and uniform distribution of glucoside as well as the affinity of the microspheres to bind with boron, evidenced via fluorescence spectroscopy measurements.
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Jiangxuan Song Jin‐Han Jeon Il‐Kwon Oh K. C. Park 《Macromolecular rapid communications》2011,32(19):1583-1587
We report here a facile synthesis of high performance electro‐active polymer actuator based on a sulfonated polyimide with well‐defined silver electrodes via self‐metallization. The proposed method greatly reduces fabrication time and cost, and obviates a cation exchange process required in the fabrication of ionic polymer‐metal composite actuators. Also, the self‐metallized silver electrodes exhibit outstanding metal‐polymer adhesion with high conductivity, resulting in substantially larger tip displacements compared with Nafion‐based actuators.
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Michael J. Bojdys Nikolai Severin Jürgen P. Rabe Andrew I. Cooper Arne Thomas Markus Antonietti 《Macromolecular rapid communications》2013,34(10):850-854
The carbon nitride poly(triazine imide) with intercalated bromide ions is a layered, graphitic material of 2D covalently bonded molecular sheets with an exceptionally large gallery height of 3.52 Å due to the intercalated bromide anions. The material can be cleaved both mechanically and chemically into thin sheets and scrolls analogous to the carbon‐only systems graphite and graphene.
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Wayne L. Mattice Numan Waheed Fatih Erguney 《Macromolecular theory and simulations》2006,15(7):529-537
Summary: Nonrandomness in the distribution of rotational isomeric states along a flexible unperturbed chain reduces its conformational entropy. Pairwise interdependence of the bonds is a necessary, but not sufficient, condition for a significant reduction. The reduction in conformational entropy from this source can be as severe as a factor of three. It is generally more severe for isotactic chains than for the syndiotactic chains constructed from the same monomer. Surprising effects are sometimes seen, such as the nearly identical reductions in conformational entropy for polydimethylsiloxane, a very flexible chain, and for poly(methyl methacrylate), a much stiffer chain.
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Corinna M. Preuss Anja S. Goldmann Vanessa Trouillet Andreas Walther Christopher Barner‐Kowollik 《Macromolecular rapid communications》2013,34(8):640-644
Mussel adhesives function as tools for surface modifications of a wide variety of materials due to their remarkable adhesion properties. Herein, a combination of bioinspired mussel adhesives based on a dopamine derivative, polymer chemistry, and well‐established Diels–Alder (DA) chemistry leads to a bioinspired switchable surface system that possesses the capability of attaching and detaching specific polymers on demand. A dopaminemaleimide compound, which has been attached to a gold surface under maritime conditions undergoes DA‐ and retro‐DA‐click‐conjugations with cyclopentadiene‐carrying PEG chains. The surface attachment and the subsequent DA/rDA cycles are evidenced via XPS analysis.
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Zhenglong Yang Junwei Wang Kun Huang Jin Ma Zhenzhong Yang Yunfeng Lu 《Macromolecular rapid communications》2008,29(5):442-446
Novel mesoporous polymers functionalized with carboxylic, sulfonic, and amino groups were synthesized by self‐organization of surfactant and functionalized phenolic building oligomers followed by surfactant removal. These materials have relatively large surface area, with a large number of functional groups on the pore walls, which may provide this new class of materials with enhanced adsorption capability and selectivity.
10.
Hitoshi Sashiwa Naoki Yamamori Yoshifumi Ichinose Junzo Sunamoto Sei‐ichi Aiba 《Macromolecular bioscience》2003,3(5):231-233
The Michael reaction of chitosan with acrylic acid was carried out successfully, even in water alone as the reaction medium. As a consequence of its good solubility in water, the reaction product, N‐carboxyethylchitosan, showed excellent biodegradable properties with standard activated sludge.
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Carlos Peniche Mar Fernndez Alberto Gallardo Antonio Lpez‐Bravo Julio San Romn 《Macromolecular bioscience》2003,3(10):540-545
Porous microspheres have been prepared by suspension free radical polymerization of acrylic acid (AA) in the presence of chitosan (CHI). The microspheres were characterized by FTIR and environmental SEM. The PAA content of the microspheres was estimated to be in the range 45–50 wt.‐%. The swelling degree of these particles is almost constant in the range 2 < pH < 5, but it increases considerably as the pH is raised from 5 to 10. The release profiles of microspheres loaded with meclofenamic acid (MF) were determined at pH 2, 7.4, and 10. The in vitro release of MF at different pHs was modulated by the solubility of the drug. These microcapsules are biodegradable and presented good biocompatibility and biodegradability during in vivo experiments.
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Arkadiy D. Litmanovich Vadim V. Podbelskiy Yaroslav V. Kudryavtsev 《Macromolecular theory and simulations》2010,19(5):269-277
An algorithm was developed to generate an ensemble of statistical multiblock AB copolymer chains via a polymer‐analogous reaction with acceleration. Ordering in the cylindrical ensemble of such chains is simulated via successive rotation of chains until an arrangement with the maximum energy of attraction between each two nearest chains is attained. The master relation of the ordering and the relations between AA, BB and AB contact fractions were found. Those relations permit to estimate the adequacy of modeling polymers of finite length. Influence of a chain structure, length, and interchain interactions on the ordering efficiency was studied.
13.
Tatsuo Kaneko Ayako Ichikawa Jian Ping Gong Yoshihito Osada 《Macromolecular rapid communications》2003,24(13):789-792
The complexation of bile acids with various solvated polycations was studied. A one‐to‐one complex was precipitated when an aqueous solution of cholic acid sodium salt (CA) was mixed with aqueous solutions of 3,3‐ionene and grew to form crystals with needle‐like morphology, 3 millimeters in length. Hydrogen bonding of hydroxyls at the steroid face and the spacing between cationic sites of polycations were crucial for the formation of the giant needle.
14.
Xiaohu Guo Marco Pinna Andrei V. Zvelindovsky 《Macromolecular theory and simulations》2007,16(9):779-784
Cell dynamics simulation (CDS) is a very promising approach to model dynamic processes in block copolymer systems at the mesoscale level. It is difficult to implement a real time and experimental‐scale simulation with traditional serial algorithms because of the expensive computation. A parallel, spatial decomposition‐based algorithm for large‐scale CDS is proposed. With the efficient strategy of domain decomposition and the fast method of neighbouring points location, we greatly reduce the calculating and communicating cost. The numerical results indicate that the proposed parallel algorithm can provide an efficient procedure for computer simulation of block copolymer systems of experimental size.
15.
A novel semi‐interpenetrating polymer network based on alginate and poly(N‐isopropylacrylamide) (PNiPAAm) has been synthesized that shows response to temperature and magnetic fields. Highly homogeneous porous hydrogels are obtained by copolymerizing N‐isopropylacrylamide and bis‐acrylamide in the presence of an aqueous alginate solution. The synthesis of magnetic iron oxides by in‐situ oxidation of iron cations coordinated to the alginate network results in a hydrogel with an enhanced deswelling rate with respect to pure PNiPAAm.
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Xiyan Liu Zhongwei Niu Huifang Xu Meili Guo Zhenzhong Yang 《Macromolecular rapid communications》2005,26(12):1002-1007
Summary: Crosslinkable composite microspheres were prepared by heterocoagulation of epoxy resin nanoparticles onto polystyrene microspheres. The corresponding hollow microspheres were created after removal of the core. The surface morphology was tunable from smooth to rough by controlling the degree of crosslinking of the shell nanoparticles. A positively charged polyelectrolyte could be easily adsorbed onto the composite microspheres to facilitate further synthesis, e.g., layer‐by‐layer deposition and a sol‐gel process to form inorganic materials.
17.
Liviu Sacarescu Angeliki Siokou Rodinel Ardeleanu Gabriela Sacarescu Mihaela Simionescu 《Macromolecular rapid communications》2006,27(13):1054-1059
Summary: This paper presents the structural influence of the Si H functionality on the physicochemical properties of polysilanes. New low‐temperature restructuring processes were discovered using thermal analysis (TGA, DSC). Photoluminescent (FL) and X‐ray photoelectron spectroscopy (XPS) measurements revealed the optoelectronic properties‐chemical structure relationship of the synthesized polymers.
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Synthesis of Aromatic Macrocyclic Amphiphiles and their Self‐Assembling Behavior in Aqueous Solution
A triblock amphiphilic macrocycle consisting of a macrocyclic aromatic segment, a hydrophilic oligo(ethylene oxide) branch, and a hydrophobic alkyl dendron is successfully synthesized and characterized. The resulting cyclic amphiphile is observed to self‐assemble into hollow double‐layered capsules in aqueous solution, as confirmed by dynamic light scattering and cryogenic transmission electron microscopy investigations. The capsules are able to encapsulate hydrophobic guest molecules through aromatic interactions with high stability.
19.
Summary: The coordinative polymerization/cyclization of a flexible monodisperse di‐terpyridine ligand with iron(II ) chloride is reported. Matrix‐assisted laser desorption ionization time‐of‐flight (MALDI‐TOF) investigations showed the preferred formation of a [2 + 2] macrocycle, but also larger aggregates (cycles or linear oligomers) with up to 10 monomer units were found. Because of its C16‐spacer, the solubility is sufficient for performing viscosity experiments in CHCl3/MeOH solution. A viscosity titration revealed a maximum in viscosity at the 1‐to‐1 ratio of iron(II ) ions to di‐terpyridine‐ligands, which indicates the formation of extended oligomers, polymers, catenanes and/or cycles at that ratio.
20.
Klaus Tauer Samira Nozari A. M. Imroz Ali Steffen Kozempel 《Macromolecular rapid communications》2005,26(15):1228-1232
Summary: Optical absorption measurements are used for the first time to investigate the uptake of pure organic solvents or solutions by latex particles. Sorption into glassy polymer particles is a two‐stage process with distinctly different characteristic times, which reflects that an initial softening of the outer particle layer facilitates further uptake. The sorption of solutions containing highly water‐insoluble compounds allows the preparation of composite nanoparticles, which are hardly accessible by other routes.