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1.
Kai Du Aihua H. He Xin Liu Charles C. Han 《Macromolecular rapid communications》2007,28(24):2294-2299
Highly exfoliated poly(propylene) (PP)/clay nanocomposites with obvious improvements in both the tensile strength and toughness have been prepared by a novel TiCl4/MgCl2/imidazolium‐modified montmorillonite (IOHMMT) compound catalysts. Through this approach, in situ propylene polymerization can actually take place between the silicate layers and lead not only to PP with a high isotacticity and molecular weight, but also to a highly exfoliated structure even at high clay content levels (as high as 19 wt.‐%).
2.
Sei‐ichi Ishii Rieko Furuyama Naoto Matsukawa Junji Saito Makoto Mitani Hidetsugu Tanaka Terunori Fujita 《Macromolecular rapid communications》2003,24(7):452-456
The catalytic properties of bis(phenoxy‐imine) Zr and Hf complexes incorporating perfluorophenyl groups with methylaluminoxane were investigated. The fluorinated complexes produced far higher‐molecular‐weight polyethylenes and ethylene/propylene copolymers with increased activities compared with the non‐fluorinated congeners. Moreover, the fluorinated complexes displayed a higher incorporation ability for propylene.
3.
Xuejing Zheng Makarand S. Pimplapure Günter Weickert Joachim Loos 《Macromolecular rapid communications》2006,27(1):15-20
Summary: A morphological investigation was carried out on different Ziegler‐Natta catalysts during the early stages of propylene homo‐ and propylene‐ethylene copolymerization. For similar polymerization conditions, but dependent on the nature of the catalysts, fragmentation occurs layer‐by‐layer or instantaneously into a large amount of small pieces. However, the incorporation of comonomer ethylene slows down the fragmentation progress. This is believed to be the result of the higher mobility of the just formed propylene‐ethylene copolymer molecules at the active sites.
4.
Julien Nicolas Giuseppe Mantovani David M. Haddleton 《Macromolecular rapid communications》2007,28(10):1083-1111
Combinations of synthetic and natural macromolecules offer a route to new functional materials. While biological and polymer chemistry may not be natural bedfellows, many researchers are focusing their attention on the benefits of combining these fields. Recent advances in living radical polymerization have provided methods to build tailor‐made macromolecular moieties using relatively simple processes. This has led to a plethora of block copolymers, end‐functional polymers and polymers with a whole range of biological recognition abilities. This review covers work carried out until late 2006 combining living radical polymerization with proteins and peptides in the rapidly‐expanding field of bioconjugation.
5.
Alexander A. Auer Antje Richter Anatoly V. Berezkin Daria V. Guseva Stefan Spange 《Macromolecular theory and simulations》2012,21(9):615-628
Twin polymerization is a novel technique for synthesizing hybrid polymers with domain sizes in the nanometer range. While a broad variety of monomers have been investigated, the mechanistic details and the most important influences on the nanostructure formation are unknown. A scale bridging approach is presented to simulate the twin polymerization of 2,2'‐spirobi[4H‐1,3,2‐benzodioxasiline]. This approach is based on detailed quantum chemical calculations that yield insight into reactivity and structure at the molecular level while the kinetics of the network formation process and the influences that govern structure formation are investigated at the mesoscopic level by a coarse‐grained simulation.
6.
Surbhi Mahajan Byoung‐Ki Cho Jürgen Allgaier Lewis J. Fetters Geoffrey W. Coates Ulrich Wiesner 《Macromolecular rapid communications》2004,25(22):1889-1894
Summary: Stepwise anionic polymerization, catalytic hydrogenation, and atom transfer radical polymerization were performed to synthesize an amphiphilic ABC triblock copolymer, poly(ethylene‐alt‐propylene)‐block‐poly(ethylene oxide)‐block‐poly(hexyl methacrylate) (PEP‐b‐PEO‐b‐PHMA), with hydrophilic PEO as the middle block. The resulting block copolymers have well‐defined molecular weights and narrow molecular weight distributions as revealed by 1H NMR spectroscopy and gel permeation chromatography.
7.
Per B. Zetterlund Md. Nur Alam Hideto Minami Masayoshi Okubo 《Macromolecular rapid communications》2005,26(12):955-960
Summary: The nitroxide‐mediated controlled/living free radical copolymerization of styrene and divinylbenzene using a polystyrene‐TEMPO macroinitiator in aqueous miniemulsion and in bulk have been investigated. The crosslink densities were estimated based on the content of pendant vinyl groups as determined by 1H NMR. Considerably lower crosslink densities were revealed in the miniemulsion than in the corresponding bulk system. The rate of polymerization in the miniemulsion increased with decreasing particle size, and was significantly higher than in bulk.
8.
Xiaobing Wang Xiaobin Ding Zhaohui Zheng Xinhua Hu Xu Cheng Yuxing Peng 《Macromolecular rapid communications》2006,27(14):1180-1184
Summary: Magnetic nanoparticles have been prepared by a co‐precipitation method and modified with methacryloxypropyltrimethoxysilane. Magnetic molecularly imprinted polymer particles have been prepared by suspension polymerization in silicone oil. The particles possess a high affinity to the template molecules and are rapidly separated under a magnetic field.
9.
Robert Eberhardt Markus Allmendinger Bernhard Rieger 《Macromolecular rapid communications》2003,24(2):194-196
Highly efficient formation of poly(propylene carbonate) can be achieved in the coupling of CO2 and propylene oxide assisted by 4‐(N,N‐dimethylamino)pyridine (DMAP) and catalyzed with salen chromium(III) chloride by using DMAP/Cr ratios of less than 2. Under these conditions a possible backbiting mechanism is suppressed, leading to only minor amounts of cyclic carbonate as a side product.
10.
Ronan C. Nicolas Carl‐Eric Wiln Michael Roth Rudolf Pfaendner Roswell E. King 《Macromolecular rapid communications》2006,27(12):976-981
Summary: The synthesis of azoalkanes such as azocyclohexane ( 1 ) and 4,4′‐bis(cyclohexylazocyclohexyl)methane ( 2 ) and their use as flame retardants in polymeric substrates is reported. For the first time it is demonstrated that azoalkanes alone can effectively provide flame retardancy and self‐extinguishing properties to poly(propylene) films at a very low concentration of 0.25 to 0.5 wt.‐%. All the poly(propylene) formulations passed DIN 4102‐1/B2 standards and the instant azoalkane‐containing poly(propylene) blends show no discoloration.
11.
Summary: Polyaniline‐vanadium oxide nanocomposite nanosheets with thickness between 10 and 20 nm, and lateral dimensions in the range of hundreds of nanometers to several microns have been synthesized by in situ intercalation polymerization of aniline with layered V2O5 under hydrothermal conditions. The product was characterized by field‐emission scanning electron microscopy (FE‐SEM), transmission electron microscopy (TEM), Fourier transform infrared (FT‐IR) spectroscopy, and X‐ray diffractometer (XRD). The effects of the concentration of aniline and reaction temperature on the morphologies of polyaniline‐vanadium oxide nanocomposites have also been investigated.
12.
Radislav A. Potyrailo Ronald J. Wroczynski James E. Pickett Malgorzata Rubinsztajn 《Macromolecular rapid communications》2003,24(1):123-130
A new general approach for rapid performance‐screening of polymer compositions is provided. Multiple compositions are generated as one‐dimensional libraries in a microextruder with step‐ or gradient‐composition changes in 2–10 g of polymer in < 1 min. To accelerate testing, environmental stress is applied to only local regions, followed by high‐sensitivity spatially resolved characterization. We applied our methodology for weathering of arrays of polymeric compositions and provided ranking of polymer/UV absorber compositions equivalent to traditional weathering data while achieved 20 times faster.
13.
Harsha D. Magurudeniya Prakash Sista Jacob K. Westbrook Taryn E. Ourso Khuong Nguyen Marie C. Maher Mussie G. Alemseghed Michael C. Biewer Mihaela C. Stefan 《Macromolecular rapid communications》2011,32(21):1748-1752
A nickel α‐diimine catalyst was used for Grignard metathesis (GRIM) polymerization of 2,5‐dibromo 3‐hexylthiophene and 2‐bromo‐5‐iodo‐3‐hexylthiophene monomers. GRIM polymerization of 2‐bromo‐5‐iodo‐3‐hexylthiophene generated regioregular polymers with molecular weights ranging from 3 000 to 12 000 g · mol−1. The nickel α‐diimine catalyst was also successfully used for the GRIM polymerization of a bulky benzodithiophene monomer.
14.
Roman Tkachov Volodymyr Senkovskyy Ulrich Oertel Alla Synytska Marta Horecha Anton Kiriy 《Macromolecular rapid communications》2010,31(24):2146-2150
A ‘grafting‐from’ approach to synthesize microparticle‐supported conjugated polyelectrolyte brushes is presented. Poly(3‐bromohexylthiophene) is selectively grown from monodisperse organosilica microparticles by surface‐initiated Kumada catalyst‐transfer polycondensation (SI‐KCTP) and then ionizable amino groups are introduced by a two‐step polymer analogous transformation. Optical properties of the resulting microparticle‐supported conjugated polyelectrolyte brushes were found to be dependent on the surrounding chemical environment and thus the particles are promising materials for sensor applications.
15.
Qiong Zhang Zhijun Ning Yongli Yan Shixiong Qian He Tian 《Macromolecular rapid communications》2008,29(3):193-201
Resorting to ‘click chemistry’, four photochromic dendrimers, A‐Tri‐SP, B‐Tri‐SP, C‐Tri‐SP, and D‐Hex‐SP, have been synthesized facilely in sound yields of 85, 88, 94, and 80%, respectively. These dendrimers have been obtained by the straightforward coupling of azido‐attached photochromic spiropyran units to acetylenic‐terminated dendritic cores. The photochromic dendrimers show typical photochromic properties both in tetrahydrofuran solution and in poly(methyl methacrylate) film. They are demonstrated to be endowed with superior performance in comparison to the corresponding spiropyran monomer in terms of larger optical density, better stability of the open ring form, higher sensitivity towards the coordination of ferric ions, and better two‐photon absorption properties.
16.
Ryszard Szymanski 《Macromolecular theory and simulations》2013,22(4):221-224
The importance of taking into account the principle of microscopic reversibility in the analysis of complex copolymerization systems is demonstrated. The analysis of a reversible copolymerization system in which segmental exchange is possible from the point of view of the reaction microreversibility proves that hetero‐reshuffling rate constants depend on homo‐reshuffling rate constants and copolymerization thermodynamics.
17.
Min‐Min Fan Xi Zhang Jie Qin Bang‐Jing Li Xun Sun Sheng Zhang 《Macromolecular rapid communications》2011,32(19):1533-1538
This paper studies a kind of hollow nanospheres prepared by self‐assembly β‐cyclodextrins (β‐CDs) and poly(ethylene oxide)‐poly(propylene oxide)‐poly(ethylene oxide) (pluronic F127) for gene delivery. It was found that this kind of hollow nanospheres enable load PEI10K/DNA and the resulting F127 NH2 βCD/(PEI10K/DNA) with 0.08 µg/well DNA display equal or higher gene delivery capability compared to PEI10K/DNA with 1 µg/well DNA in the absence or presence of serum. The cytotoxicity of the nanospheres was over 100 times lower than that of PEI10K.
18.
Kalle Lintinen Niko Granqvist Alexander Efimov Helge Lemmetyinen 《Macromolecular rapid communications》2010,31(22):1977-1980
By using an advanced polarization modulation infrared reflection adsorption spectroscopy (PM‐IRRAS) device it is possible to study the photopolymerization of an ultrathin layer of a porphyrin monomer in real time. The method can be compared with the indirect UV/Vis method previously introduced by our group. With PM‐IRRAS it is possible to analyze polymerization kinetics of photopolymerization at various temperatures to determine the activation energy of the reaction.
19.
One‐dimensional methyl orange fibrils can be easily prepared. They are stable in acidic aqueous solutions and soluble in neutral water. When used to synthesize conducting polymer microtubules, the fibrils act as “hard templates” formally but as “soft templates” effectively. Microtubular structures of polypyrrole, polyaniline, and poly(3,4‐ethylenedioxythiophene) have been achieved successfully via such water‐soluble versatile templates.
20.
Juan Peng Yanchun Han Wolfgang Knoll Dong Ha Kim 《Macromolecular rapid communications》2007,28(13):1422-1428
We have systematically studied the thin film morphologies of asymmetric polystyrene‐block‐poly(ethylene oxide) (PS‐b‐PEO) diblock copolymer subjected to solvent vapors of varying selectivity for the constituent blocks. Upon a short treatment in neutral or PS‐selective vapor, the film exhibited a highly ordered array of hexagonally packed, cylindrical microdomains. In the case of PEO selective vapor annealing, such ordered cylindrical microdomains were not obtained. Instead, fractal patterns on the microscale were observed and their growth processes investigated. Furthermore, hierarchical structures could be obtained if the fractal pattern was exposed to neutral or PS selective vapor.