Star polymers are branched polymers characterized by multiple linear chains linked to a central core.1-4 The unique chain topology imparts valuable properties depending critically on the molecular
Star polymers are branched polymers characterized by multiple linear chains linked to a central core.1-4 The unique chain topology imparts valuable properties depending critically on the molecular
作者：
Fang FengRu ChengFenghua MengChao DengJan FeijenZhiyuan ZhongSchool of Chemical and Bioengineering
Jiangsu Key Laboratory for Environment Functional MaterialsSuzhou University of Science and TechnologySuzhou 215009China Biomedical Polymers Laboratoryand Jiangsu Key Laboratory of Advanced Functional Polymer Design and ApplicationCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China Biomedical Polymers Laboratory
and Jiangsu Key Laboratory of Advanced Functional Polymer Design and ApplicationCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China
作者：
Yaowen LiYujin ChenJiangsu Key Laboratory of Advanced Functional Polymer Design and Application
Department of Polymer Science and Engineering College of Chemistry Chemical Engineering and Materials Science Soochow University Suzhou 215123 P. R. China. Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application Department of Polymer Science and Engineering College of Chemistry Chemical Engineering and Materials Science Soochow University Suzhou 215123 P. R. China
The classic results of de Gennes and Odijk describe the mobility of a semiflexible chain confined in a nanochannel only in the limits of very weak and very strong confinement, respectively. Using Monte Carlo sampling ...
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The classic results of de Gennes and Odijk describe the mobility of a semiflexible chain confined in a nanochannel only in the limits of very weak and very strong confinement, respectively. Using Monte Carlo sampling of the Kirkwood diffusivity with full hydrodynamic interactions, we show that the mobility of a semiflexible chain exhibits a broad plateau as a function of extension before transitioning to an Odijk regime, and that the width of the plateau depends on the anisotropy of the monomers. For the particular case of DNA in a high ionic strength buffer, which has highly anisotropic monomers, we predict that this Rouse-like behavior will be observed over most of the measurable chain extensions seen in experiments.
A series of poly（p-phenylenevinylene）s （PPVs） with good solubility were synthesized from thermal elimination of precursor poly（2,5-didodecyloxy-p-phenylenevinylene） at different temperature via Wessling method. ...
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A series of poly（p-phenylenevinylene）s （PPVs） with good solubility were synthesized from thermal elimination of precursor poly（2,5-didodecyloxy-p-phenylenevinylene） at different temperature via Wessling method. The polymer photophysics were influenced by the thermal elimination condition, which was consistent with NMR and IR characterizations. The additional absorption peak at longer wavelength and the red-shifted emission maximum both in solution and in film, for PPVs obtained at high elimination temperature, indicated the existence of longer conjugated blocks in these systems. The emission maximum for drop-cast film （436 nm） for PPV obtained under 200 ℃ （PPV200） was 16 nm blue shifted to the spin-coated films （452 nm） or 29 nm to the solution （465 nm）. The SEM study showed drop-cast film had the morphology of isolated conjugated particles in the matrix while blurry linear structure was found for spin-coated film, which was consistent with the photophysics. The discussion about this difference was carried out based on the consideration of the flexibility of the polymer chains and different conjugated length of PPV in different states.
This study aimed at the synthesis of silica particles grafted with better-defined homopolymers and block copolymers by tandem approach.Z-functionalized Sbenzyl S’-(3-trimethoxysilyl)propyltrithiocarbonate(BTPT)was us...
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This study aimed at the synthesis of silica particles grafted with better-defined homopolymers and block copolymers by tandem approach.Z-functionalized Sbenzyl S’-(3-trimethoxysilyl)propyltrithiocarbonate(BTPT)was used as a couplable RAFT agent to synthesize the target inorganic-organic *** coupling reaction and RAFT process using silica particles and BTPT as raw materials efficiently afforded homopolymers grafted silica,and RAFTsynthesized macro chain transfer agents withω-terminal trimethoxysilane moiety were utilized to mediate graft reaction to prepare silica particles grafted with di-,tri-and tetrablock copolymers comprised of polymer segments such as polystyrene,polyacrylamides and *** the grafted chains had molecular weights ranging between 3920 and 24800 g/mol,the molar grafting ratios,which were dependent on reaction conditions and types and compositions of grafted chains,were estimated to be in the range of 15.2–101μmol/g,and grafted polymers usually had polydispersity indices lower than 1.3,revealing that the grafting process was almost *** the best of our knowledge,this versatile tandem approach is one of the most facile techniques to prepare silica particles grafted with polymeric chains with controlled molecular weight,low polydispersity and precise composition due to its minimal reaction steps,mild conditions,straightforward synthesis and satisfactory controllability.
4,4'-Biphenylene-silicas were prepared using the self-assemblies of a chiral low-molecular-weight amphiphile as templates,which exhibited chirality at both a nano and an angstrom *** CD spectra were simulated by t...
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4,4'-Biphenylene-silicas were prepared using the self-assemblies of a chiral low-molecular-weight amphiphile as templates,which exhibited chirality at both a nano and an angstrom *** CD spectra were simulated by the time-dependent density functional *** was found that the stacking and the twist of the biphenylene rings can be revealed from the first and second CD signals, *** chiral silicas have been widely developed,it is hard to know that they are chiral or not at angstrom *** on the result shown here,4,4'-bis(triethoxysilyl)-l,l'-biphenyl was used as a chiral sensor for ***,other UV active compounds with conformational chirality are proposed to be used as the chiral sensors for silicas and the other chiral materials.
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