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Two novel monovinyl β‐cyclodextrin (β‐CD) monomers are synthesized. Their chemical compositions are characterized by means of element analysis, NMR and FT‐IR spectroscopy. The results show that the synthesis techniques used are convenient and efficient. Using N‐isopropylacrylamide as a comonomer, two novel linear copolymers can also be synthesized.
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Bin Lin Frej Mighri Michel A. Huneault Uttandaraman Sundararaj 《Macromolecular rapid communications》2003,24(13):783-788
The deformation and breakup of a single polycarbonate drop in a polyethylene matrix is studied at high temperatures under simple shear flow using a transparent Couette device. We observed “parallel breakup” where the drop breaks after being stretched into a thin sheet parallel to the flow. The breakup occurs at a viscosity ratio greater than 3.5. Deborah number and a stress ratio incorporating elastic moduli can characterize the “parallel breakup”.
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Marco Aurilia Luigi Sorrentino Salvatore Iannace 《Macromolecular theory and simulations》2013,22(3):198-206
Dissipative mechanisms occurring at the interface between multiwall nanotubes (MWCNT) and an elastomeric matrix are investigated and quantitatively predicted through analytical equations derived from a micromechanical model. The effects of MWCNT aspect ratio on dissipative properties of the reinforced system are investigated at high strains (100–300%). Cyclic tensile tests illustrate that the fraction of dissipated strain energy increases with the amount of MWCNT and varies with their aspect ratio. Lower mean diameter MWCNT are able to dissipate a higher amount of strain energy. The model developed on the basis of the shear lag theory correctly predicts the dissipated strain energy at high strains, taking into account the different contributions to the mechanical behavior of nanotubes' different aspect ratios.
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Narong An Yanxia Li Yuming Yang Fusheng Yu Lisong Dong 《Macromolecular rapid communications》2006,27(12):955-960
Summary: Bisphenol A solid epoxy serves as an effective reaction compatibilizer to the bisphenol A polycarbonate (PC)/PMMA bilayer systems. Addition of epoxy to the bottom PMMA layer can retard or even prevent the dewetting of PC films by introducing crosslinking between both components at the interface. This is the first investigation of polymer bilayers stabilized by chemical reactions.
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Agnes Schulze Barbara Marquardt Sven Kaczmarek Rolf Schubert Andrea Prager Michael R. Buchmeiser 《Macromolecular rapid communications》2010,31(5):467-472
Poly(ethersulfone) membranes were surface modified in a one‐step procedure. For this purpose, the membranes were soaked with aqueous solutions of different low‐molecular weight molecules bearing diverse hydrophilic functionalities and subject to electron beam treatment. No catalysts, photoinitiators, organic solvents or other toxic reagents were used, and no additional synthetic or purification steps were required.
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Kazuki Miyake Per B. Zetterlund Bunichiro Yamada 《Macromolecular rapid communications》2004,25(22):1905-1911
Summary: Experimental and modeling studies of addition–fragmentation chain transfer (AFCT) during radical polymerization of methyl methacrylate in the presence of poly(methyl methacrylate) macromonomer with 2‐carbomethoxy‐2‐propenyl ω‐ends (PMMA‐CO2Me) at 60 °C are reported. The results revealed that AFCT involving PMMA‐CO2Me formed in situ during methyl methacrylate polymerization has a negligible effect on the molecular weight distribution.
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Henry D. Tran Koo Shin Won G. Hong Julio M. D'Arcy Robert W. Kojima Bruce H. Weiller Richard B. Kaner 《Macromolecular rapid communications》2007,28(24):2289-2293
A template‐free method for the production of polypyrrole nanofibers is presented. By adding a small amount of bipyrrole into the oxidative polymerization of pyrrole, a drastic change in the morphology of the observed material is observed from large, granular particles to nanofibrils with an average diameter of 20 nm. This simple procedure allows for the production of polypyrrole nanofibers without the presence of surfactants or other structural directing agents. The polypyrrole nanofibers can form stable water dispersions which can be cast into films of sufficient quality to function as chemical sensors for analytes such as ammonia.
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Tetsu Mitsumata Masashi Yuge Shinichi Morino Kenji Iwakura Kiyohito Koyama 《Macromolecular rapid communications》2002,23(17):1045-1048
The storage moduli, shear moduli and surface morphologies of poly(vinyl alcohol) (PVA) and alumina hybrid hydrogels were investigated. The storage moduli of hybrid hydrogels with higher alumina contents were found to be 1.5 times higher than those of PVA gels. This increase in modulus might be attributed to the cohesion of alumina to the PVA network.
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L. Tom Hillegers Aart Blokhuis Johan J. M. Slot 《Macromolecular theory and simulations》2012,21(6):400-410
A fast method is presented for the calculation of the MSD and the MWD of polymers obtained via step‐growth polymerization of polyfunctional monomers bearing identical reactive groups (i.e., systems of type “Afi”). Using this method, the complete distribution can be calculated rapidly, not just the statistical averages of the polymer population such as or . The computed MSD and MWD give more insight than these averages and can be compared to similar data measured on actual polymer systems. The low‐ and intermediate molecular size/weight part of the distribution curves are calculated using a recurrence scheme, while the high‐molecular tail (large and very large polymers) of the distributions is derived from an asymptotic approximation of the associated generating functions.
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Antje Britze Katrin Moosmann Evelin Jhne Hans‐Jürgen Adler Dirk Kuckling 《Macromolecular rapid communications》2006,27(22):1906-1912
Summary: Phosphonate groups were introduced into block copolymers of styrene derivatives either as single end‐groups or as small blocks using nitroxide‐mediated radical polymerization. In order to combine the hydrophobic and hydrophilic segments, block copolymers with N,N‐dimethyl acrylamide were synthesized. After hydrolysis to phosphonic acid groups, adsorption of the polymer onto metal oxides was possible.
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Tingyang Dai Kai Chen Xutang Qing Yun Lu Jinsong Zhu Feng Gao 《Macromolecular rapid communications》2010,31(5):484-489
Polymeric core–shell microstructures have been constructed through a new method, namely sequential precipitation, which is intrinsically a self‐assembly and phase separation process. High‐quality poly(vinyldene fluoride)–polycarbonate–lithium perchlorate composite films with spherical core–shell microstructures have been prepared and determined to consist of conducting cores and insulating shells. Because of the percolation effect, the resulting materials present a dielectric constant as high as 104–107 at the threshold.
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We describe an enzyme‐responsive polymeric vehicle, which is of great interest in controlled drug delivery, biosensing, and other related areas. The polymer synthesized using lipase as catalyst in DMSO has a favorable molecular structure that is quickly hydrolyzed by lipase in aqueous phase, and allows a fast release of encapsulated molecules.
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Yue Jin Xiao‐Ding Xu Chang‐Sheng Chen Si‐Xue Cheng Xian‐Zheng Zhang Ren‐Xi Zhuo 《Macromolecular rapid communications》2008,29(21):1726-1731
A series of bioactive amphiphilic peptide derivatives that contain the RGD (Arg‐Gly‐Asp) sequence have been designed and prepared by the standard solid‐phase peptide synthesis (SPPS) technique. The influence of the molecular structure and pH change on the morphology of the amphiphilic peptide derivatives in aqueous solution is investigated. The results reveal that the amphiphilic peptide derivatives with different molecular structures exhibit different self‐assembly behavior in response to environmental changes. Furthermore, by adjusting the pH, the molecular interactions of amphiphilic peptide derivatives are tuned, which results in a morphology change.
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In this work, the process of spin dewetting of a polymer solution on a topographically patterned PDMS mold was used for fabrication of micro‐ and nanaoscale polymer structures. Spin coating was used to provide a fast and reproducible coating. This simple technique was capable of producing a wide range of polymer feature geometries from a single microfabricated mold. This experimental study looks at the effects of the original mold feature geometry as well as the polymer solution concentration on the resultant microstructures. Polystyrene and poly(propyl methacrylate) were used as model polymers. Features with film thickness ranging from <100 nm to >5 µm were obtained using this technique. The process was also extended to fabrication of nanoscale features.
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Tjasa Vrlinic Dominique Debarnot Gilbert Legeay Arnaud Coudreuse Benaissa El Moualij Willy Zorzi Armand Perret‐Liaudet Isabelle Quadrio Miran Mozetic Fabienne Poncin‐Epaillard 《Macromolecular bioscience》2012,12(6):830-839
New non‐fouling tubes are developed and their influence on the adhesion of neuroproteins is studied. Recombinant prion proteins are considered as a single component representative of hydrophobic proteins. Samples are stored for 24 h at 4 °C in tubes coated with two different coatings: poly(N‐isopropylacrylamide) as a hydrophilic surface and a plasma‐fluorinated coating as a hydrophobic one. The protein adhesion is monitored by ELISA tests, XPS and confocal microscopy. It appears that the highest recovery of recombinant prion protein in the liquid phase is obtained with the hydrophilic surface while the hydrophobic character of the storage tube induces an important amount of biological loss. However, the recovery is not complete even for tubes coated with poly(N‐isopropylacrylamide).