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1.
A versatile approach to fabricate monodisperse poly[styrene‐co‐(divinyl benzene)] (PS‐co‐DVB) microcapsules that contain a single gold nanoparticle (AuNP) has been demonstrated. Using the PS‐co‐DVB microcapsule as a microreactor, aqueous HAuCl4 and NaBH4 solutions are subsequently infiltrated. The size of the resulting AuNP inside of the PS‐co‐DVB microcapsules is easily tunable by controlling the repeated infiltration cycles of aqueous HAuCl4 and NaBH4. PS‐co‐DVB microcapsules that contain a single silver and palladium nanoparticle are also obtained by following a similar protocol.
2.
Summary: Octa(propylglycidyl ether) polyhedral oligomeric silsesquioxane (OpePOSS) was used as the crosslinking agent to prepare the nanocrosslinked poly(4‐vinylpyridine) (P4VP) with POSS content up to 55.2 wt.‐%. The formation of the crosslinked structure is ascribed to the macromolecular reaction between pyridine rings of P4VP and epoxide groups of OpePOSS. The POSS‐crosslinked P4VP displayed enhanced glass transition temperatures (Tgs) and an improved thermal stability in terms of the results of thermal analysis.
3.
Jing Lv Canbin Ouyang Xiaodong Yin Haiyan Zheng Zicheng Zuo Jialiang Xu Huibiao Liu Yuliang Li 《Macromolecular rapid communications》2008,29(19):1588-1592
A novel water‐soluble poly(para‐phenylene) derivative with pendant thymine and sulfonate units (PBTS) has been prepared and its metal ion sensing properties have been investigated. PBTS exhibited a reversible and selective fluorescence quenching behavior toward Hg2+ ions as compared to Ag+, Ni2+, Mg2+, Ca2+, Hg2+, Co2+, Cd2+, Cu2+, Pb2+, Ba2+, Fe3+, and Zn2+ ions in aqueous solution. The fluorescence quenching resulted from the interpolymeric π‐stacking aggregation which was induced by the specific thymine–Hg–thymine interaction.
4.
Chun Zhang Scott M. Husson Douglas E. Hirt 《Macromolecular rapid communications》2006,27(14):1173-1179
Summary: A new approach is introduced to create submicrometer patterned surfaces using multilayer polymer films that contain alternating layers of two polymers, linear low‐density polyethylene (LLDPE) and ethylene‐co‐(acrylic acid) copolymer (EAA). Patterned templates have been prepared by microtoming the multilayer molded sheets. Regionally confined chemical functionality is confirmed by grafting an amine‐terminated biotin and adsorbing streptavidin specifically on the alternating layers of EAA.
5.
Santosh Kumar Mohammad Changez C. N. Murthy Shigeru Yamago Jae‐Suk Lee 《Macromolecular rapid communications》2011,32(19):1576-1582
Low‐molecular weight amphiphilic diblock copolymers, polystyrene‐block‐poly (2‐vinylpyridine) (PS‐b‐P2VP), and (P2VP‐b‐PS) with different block ratios were synthesized for the first time via organotellurium‐mediated living radical polymerization (TERP). For both the homo‐ and block copolymerizations, good agreement between the theoretical, and experimental molecular weights was found with nearly 100% yield in every case. The molecular weight distribution for all the samples ranged between 1.10 and 1.24, which is well below the theoretical lower limit of 1.50 for a conventional free radical polymerization. Furthermore, a very simple approach to producing highly dense arrays of titania nanoparticles (TiO2) is presented using a site‐selective reaction of titanium tetraisopropoxide within the P2VP domains of micellar film of P2VP‐b‐PS in toluene through the sol–gel method.
6.
Seok‐Ho Hwang Pingshan Wang Charles N. Moorefield Jae‐Chang Jung Jeong‐Yeol Kim Sang‐Won Lee George R. Newkome 《Macromolecular rapid communications》2006,27(21):1809-1813
Summary: An O‐hexyl‐3,5‐bis(terpyridine)phenol ligand has been synthesized and transformed into a hexagonal Zn(II)‐metallomacrocycle by a facile self‐assembly procedure capitalizing on terpyridine‐Zn(II)‐terpyridine connectivity. The structural composition was confirmed by NMR and mass spectral techniques; photo‐ and electroluminescence properties were also investigated. The OLED device shows green electroluminescent emission at 515 nm with a maximum luminance of 39 cd · m−2 and maximum efficiency of 0.16 cd · A−1.
7.
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.
8.
Francisco‐Javier Lpez‐Villanueva Frederik Wurm Andreas F. M. Kilbinger Holger Frey 《Macromolecular rapid communications》2007,28(6):704-709
A facile two‐step synthesis for branched poly(isoprene)s (PI) based on polyaddition of ABn‐type macromonomers is described. The synthesis of the macromonomers was achieved by anionic polymerization of isoprene and subsequent end‐capping of the polymers by addition of chlorodimethylsilane to the living carbanions. This led to PI‐based macromonomers with narrow polydispersity ( / < 1.15) and molecular weights in the range of 1 700 – 22 100 g · mol−1. Synthesis of the branched polymers was carried out by a hydrosilylation‐based polymerization of the macromonomers. Characterization via SEC, SEC‐MALLS, coupled SEC‐viscosimetry and 1H‐NMR‐spectroscopy supported the formation of branched structures. Interestingly, these branched polymers exhibited α‐values that were similar to those reported for hyperbranched polymers based on AB2‐monomers.
9.
Yue Cui Cheng Tao Suping Zheng Qiang He Sufen Ai Junbai Li 《Macromolecular rapid communications》2005,26(19):1552-1556
Summary: Thermosensitive polymer nanotubes can be fabricated within an aminopropylsilane‐modified porous anodic aluminum oxide membrane by surface‐initiated atom transfer radical polymerization (ATRP) followed by template removal. DSC experiments prove that the synthesized PNIPAM‐co‐MBAA copolymer nanotubes have a reversible thermosensitive behavior. The temperature‐induced changes in dimension and shape of the nanotubes were studied by AFM in real time in an aqueous environment. It indicates that the nanotubes undergo a shape alteration from an “ellipse” to “circular” shape in water upon heating to LCST or above.
10.
Severin J. Sigg Farzad Seidi Kasper Renggli Tilana B. Silva Gergely Kali Nico Bruns 《Macromolecular rapid communications》2011,32(21):1710-1715
The hemoprotein horseradish peroxidase (HRP) catalyzes the polymerization of N‐isopropylacrylamide with an alkyl bromide initiator under conditions of activators regenerated by electron transfer atom transfer radical polymerization (ARGET ATRP) in the absence of any peroxide. This is a novel activity of HRP, which we propose to name ATRPase activity. Bromine‐terminated polymers with polydispersity indices (PDIs) as low as 1.44 are obtained. The polymerization follows first order kinetics, but the evolution of molecular weight and the PDI upon increasing conversion deviate from the results expected for an ATRP mechanism. Conversion, and PDI depend on the pH and on the concentration of the reducing agent, sodium ascorbate. HRP is stable during the polymerization and does not unfold or form conjugates.
11.
Min Sang Kim Su Jong Hwang Jong Kwon Han Eun Kyung Choi Heon Joo Park Jin Seok Kim Doo Sung Lee 《Macromolecular rapid communications》2006,27(6):447-451
Summary: A pH‐sensitive block copolymer is synthesized by step polymerization and its pH‐sensitive micellization‐demicellization behavior is studied. This polymer has a hydrophilic MPEG (shell) and hydrophobic but pH‐sensitive poly(β‐amino ester) (core), which can form a self‐assembled micelle. As confirmed by fluorescence spectroscopy and dynamic light scattering (DLS), this polymer shows a sharp pH‐sensitive micellization‐demicellization behavior. It is confirmed that the pH sensitivity is affected by the molecular weight ratio between the MPEG and poly(β‐amino ester).
12.
Bo Zhu Yong He Naoki Asakawa Naoko Yoshie Haruo Nishida Yoshio Inoue 《Macromolecular rapid communications》2005,26(8):581-585
Summary: A new crystal morphology (δ form) of poly(3‐hydroxypropionate) (PHP) is found in cast and melt‐crystallized PHPs with low molecular weight, in which the PHP chains possibly adopt a 21 helix rather than the trans conformation found in the β or γ form. The fusion temperature‐ and the crystallization temperature‐dependent polymorphism are responsible for the dual morphologies and the unique growth kinetics of spherulites in the melt‐crystallized PHPs.
13.
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.‐%).
14.
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.
15.
Feng Chen Satoshi Akasaka Tomohiro Inoue Mikihito Takenaka Hirokazu Hasegawa Hiroshi Yoshida 《Macromolecular rapid communications》2007,28(22):2137-2144
The morphology of a thin film was studied for a binary mixture of asymmetric PS‐b‐PMMA block copolymers on a flat silicon wafer coated with 50 nm thick silicon oxide. AFM and TEM reveal that the PMMA cylinders orient perpendicular to the substrate by tuning the film thickness. Furthermore, grating substrates with different width and depth are used to guide the alignment of the perpendicular cylinders. As a result, an array of highly ordered, hexagonally packed PMMA cylinders in the PS matrix with a domain spacing of less than 25 nm has been produced.
16.
Xi Chen Yang Liu Yingli An Juan Lü Junbo Li Dean Xiong Linqi Shi 《Macromolecular rapid communications》2007,28(12):1350-1355
We report a simple procedure to prepare a novel Au‐micelle composite with a core‐shell‐corona structure. This composite is prepared by reduction of tetrachloroauric acid (HAuCl4 · 3H2O) in dilute aqueous solution containing polystyrene‐block‐poly(4‐vinylpyridine) micelles and poly(ethylene oxide)‐block‐poly(4‐vinylpyridine) copolymers. The micelles with a polystyrene core and a poly(4‐vinylpyridine) shell are transformed into Au‐micelle composites with a polystyrene core, a swollen hybrid Au/poly(4‐vinylpyridine) inner shell, and a poly(ethylene oxide) corona by direct physisorption of gold particles with poly(4‐vinylpyridine) chains.
17.
Francesca Bennet Tara M. Lovestead Philip J. Barker Thomas P. Davis Martina H. Stenzel Christopher Barner‐Kowollik 《Macromolecular rapid communications》2007,28(16):1593-1600
The products of the thermal degradation at 95 °C over 10 months of ω‐saturated and non‐saturated poly(methyl methacrylate) (pMMA) model compounds were identified with high accuracy via quadrupole ion trap and quadrupole ion trap‐time of flight (Q‐ToF) mass spectrometry. Analysis of the samples taken via these techniques indicated that degradation of vinyl terminated pMMA proceeds via the incorporation of oxygen via the formation of ethylene oxide type end groups, which subsequently rearrange under the expulsion of formaldehyde and 2‐oxo‐propionic acid methyl ester. The corresponding saturated model compounds were demonstrated to be stable over the same time period. The present findings highlight for the first time that poly(methyl methacrylate) degradation does not necessarily and exclusively proceed via radical intermediates.
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19.
Xuping Sun Xiue Jiang Shaojun Dong Erkang Wang 《Macromolecular rapid communications》2003,24(17):1024-1028
Dendrimer‐protected gold nanoparticles have been facilely obtained by heating an aqueous solution containing third‐generation poly(propyleneimine) dendrimers and HAuCl4 without the additional step of introducing other reducing agents. Transmission electron microscopy (TEM) and UV‐vis data indicate the size, the nucleation, and growth kinetics of gold nanoparticles thus formed, which can be tuned by changing the initial molar ratio of dendrimer to gold.
20.
Ya‐Jun Cheng Shaoying Zhou Jochen S. Gutmann 《Macromolecular rapid communications》2007,28(13):1392-1396
Nanostructured TiO2 thin films were prepared using an amphiphilic PS‐b‐PEO block copolymer as a templating agent. A good–poor solvent pair‐induced pair phase separation process was coupled with sol–gel chemistry to control the morphology of the TiO2 film in a solution of 1,4‐dioxane, concentrated HCl, and titanium tetraisopropoxide (TTIP). By varying the block copolymer concentration from 0.25 to 4.0 wt.‐% while keeping the relative ratios among 1,4‐dioxane, conc. HCl, and TTIP constant, a morphology transition from pores to lamellae was observed. The photoluminescence (PL) properties of the film composed of different morphologies were studied, and the PL properties were found to be independent of the morphologies of the mesoporous films. The mechanism of the morphology evolution with respect to the copolymer concentration is further discussed.