Xu F.J.,State Key Laboratory of Chemical Resource Engineering |
Wang Z.H.,State Key Laboratory of Chemical Resource Engineering |
Yang W.T.,State Key Laboratory of Chemical Resource Engineering
Biomaterials | Year: 2010
The ability to manipulate and control the surface properties, without altering the substrate properties, is of crucial importance in the designing of biomedical materials. In this work, surface-initiated atom transfer radical polymerization (ATRP) is employed to tailor the functionality of polycaprolactone (PCL) film surfaces in a well-controlled manner. Functional polymer brushes of glycidyl methacrylate (GMA) were prepared via surface-initiated ATRPs from the PCL film surfaces. Kinetics study revealed that the chain growth from the PCL films was consistent with a controlled process. The dense and reactive epoxide groups of the grafted P(GMA) brushes were used for the direct coupling of cell-adhesive collagen and Arg-Gly-Asp-Ser (RGDS) peptides to improve the cell-adhesion properties of the PCL film surface. These modified surfaces were evaluated by culturing of a cell line, 3T3 fibroblasts. The cell attachment and proliferation were improved remarkably on the collagen (or RGDS) functionalized PCL film surfaces. The adhesion results also indicated that the collagen-coupled PCL film surface is better for the cell-adhesion process. With the versatility of surface-initiated ATRP and the good biocompatibility nature of biomolecules, the PCL films with desirable surface functionalities can be precisely tailored to cater to various biomedical applications. © 2010 Elsevier Ltd. All rights reserved.
Luo X.,State Key Laboratory of Chemical Resource Engineering |
Luo X.,Beijing University of Chemical Technology |
Li L.,State Key Laboratory of Chemical Resource Engineering |
Li L.,Beijing University of Chemical Technology |
And 5 more authors.
Chemical Communications | Year: 2010
Achiral substituted acetylene monomers undergo aqueous catalytic emulsion asymmetric polymerizations in chiral micelles consisting of SDS and amino acid, providing optically active helical polymer emulsions. The asymmetric polymerizations lead to one-handed helical polymers, which are the origin of the optical activity of polymer emulsions. © 2010 The Royal Society of Chemistry.
Zou L.,East China Institute of TechnologyJiangxi |
Zou L.,State Key Laboratory of Chemical Resource Engineering
Advanced Materials Research | Year: 2010
Crosslinked amphoteric starches (CAS) with quaternary ammonium cationic and carboxymethyl anionic groups were prepared by a microwave radiation method. Their adsorption behavior for Cr(VI) was investigated. The results showed that high the degree of substitution (DS) of modified starch was favorable to the synthesis by the microwave heating and crosslinked amphoteric starches prepared with higher the adsorption capacity than by the drying reaction. The adsorption capacity increases with the increasing cationic groups and decreased with increasing degree of substitution of anionic groups. The adsorption capacity was found to follow the Langmuir isotherm. © (2010) Trans Tech Publications.
Atif M.,Polytechnic University of Turin |
Atif M.,University Road |
Bongiovanni R.,Polytechnic University of Turin |
Yang J.,State Key Laboratory of Chemical Resource Engineering
Polymer Reviews | Year: 2015
This review article is a comprehensive study of different approaches utilized by various researchers for UV-cure epoxy composites through the cationic route in the form of transparent or colored composites either in thin films or thick dimensions. Generally UV curing is applied on thin and transparent materials, yet attempts are being made to cure intensely colored and thick composite samples. In recent times, thick sample UV-curing has been actively explored to decrease the processing and fabrication expenses of complex assemblies. In this article, data has been reviewed about epoxy curing with methodological trends, not only in thin films but also in thick samples. © 2015 Taylor and Francis Group, LLC.
Zhou C.,State Key Laboratory of Chemical Resource Engineering |
Xu J.,State Key Laboratory of Chemical Resource Engineering
Current Organic Synthesis | Year: 2013
A variety of chiral bisamide ligands have been prepared and widely used in asymmetric catalytic syntheses with highly regio-and enantioselective products, especially in the transition-metal-catalyzed asymmetric allylic alkylation reactions. The achievements in the asymmetric allylic alkylation reactions with various nucleophiles have been reviewed. The applications of some typical chiral bisamides in decarboxylative asymmetric allylic alkylation of enol carbonates, [3+2] cycloaddition of vinyl cyclopropanes and alkylidene azlactones, and aldol reactions are also introduced. © 2013 Bentham Science Publishers
Wang L.,State Key Laboratory of Chemical Resource Engineering |
Wang L.,Beijing University of Chemical Technology |
Guo Z.-X.,Tsinghua University |
Yu J.,Tsinghua University
Industrial and Engineering Chemistry Research | Year: 2014
The morphology and properties of polyamide 6 (PA6)/poly(butylene terephthalate) (PBT) blends filled by three types of glass fibers (GF) with different surface properties were investigated. The GF were unmodified or surface-modified for PA6 or PBT, denoted as GF(Pris), GF(PA6), and GF(PBT), respectively. The incorporation of 15 wt % of GF with different surface properties all led to a transition from a cocontinuous (at least a part of each phase penetrates the whole volume in a coherent and continuous manner) to a sea-island (separated domains dispersed in a continuous matrix) morphology with PA6 being the matrix phase when PA6/PBT equaled 45/55. GF(Pris) was always encapsulated by PA6, while the encapsulating layers on the surfaces of GF(PA6) and GF(PBT) changed from PBT to PA6 with increasing PA6 contents. The morphological changes induced by GF caused more PBT to crystallize at a lower temperature and enhanced the alkali tolerance of the blend significantly. © 2013 American Chemical Society.
Zheng X.,State Key Laboratory of Chemical Resource Engineering |
Zheng X.,Beijing University of Chemical Technology |
Yue M.,State Key Laboratory of Chemical Resource Engineering |
Yue M.,Beijing University of Chemical Technology |
And 6 more authors.
Polymer Chemistry | Year: 2012
The present article proposes a novel metal/odor/color-free strategy, called Cycloketyl Radical Mediated Living Polymerization (CMP). It is based on the use of the cyclo-compound 9,9′-bixanthene-9,9′-diol (BIXANDL), and proceeds similarly to Living Radical Polymerization (LRP) under mild thermal or photo stimuli. This technique shows significant potential for the practical large-scale production of industrial polymers. © 2012 The Royal Society of Chemistry.
Chen Y.,State Key Laboratory of Chemical Resource Engineering |
Liu L.,State Key Laboratory of Chemical Resource Engineering |
Liu L.,Key Laboratory of Carbon Fiber and Functional Polymers |
Yang Q.,State Key Laboratory of Organic Inorganic Composites |
And 5 more authors.
Langmuir | Year: 2013
In this work, nonequilibrium molecular dynamics simulations were performed to investigate the dispersion and spatial distribution of spherical nanoparticles (NPs) in polymer matrix under oscillatory shear flow. We systematically analyzed the influences of four important factors that consist of NP-polymer interfacial strength, volume fraction of NPs, shear conditions, and polymer chain length. The simulation results showed that the oscillatory shear can greatly improve the dispersion of NPs, especially for the polymer nanocomposites (PNCs) with high NP-polymer interfacial strength. Under specific shear conditions, the NPs can exhibit three different spatial distribution states with increasing the NP-polymer interfacial strength. Interestingly, at high interfacial strength, we observed that the NPs can be distributed on several layers in the polymer matrix, forming the PNCs with sandwich-like structures. Such well-ordered nanocomposites can exhibit a higher tensile strength than those with the NPs dispersed randomly. It may be expected that the information derived in present study provides a useful foundation for guiding the design and preparation of high-performance PNCs. © 2013 American Chemical Society.
Meng F.,State Key Laboratory of Chemical Resource Engineering |
Xu J.,State Key Laboratory of Chemical Resource Engineering
Amino Acids | Year: 2010
A series of phosphinopeptides containing C-terminal α- aminoalkylphosphinic acids were prepared in good yields directly in one-pot reactions of 2-(N-benzoxycarbonylamino)alkanamides/peptide amides, aldehydes, and aryldichlorophosphines, followed by hydrolysis. In the current method, the peptide bond was formed in a Mannichtype reaction. © Springer-Verlag 2010.
Xia C.,Capital Medical University |
Xia C.,State Key Laboratory of Chemical Resource Engineering |
Yanjun X.,Beihang University |
Ning W.,Beihang University
Electrochimica Acta | Year: 2012
In this paper, hollow hematite nano-polyhedrons (Fe-HNPs) were synthesized via a facile solution route. The abundance of high indexed facets was demonstrated by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD) analysis. A new electrochemical biosensor for nitrite determination was then proposed by using the hematite hollow nanopolyhedron as the sensing layer. Electrochemical tests showed that the Fe-HNPs could act as efficient enzyme-like electron mediators for nitrite oxidation. As a result, the Fe 2O 3 modified biosensor exhibited excellent performance for the determination of nitrite with a response time of <10 s, linear range between 0.009 and 3 mM, and sensitivity as 19.83 μA mM -1. A high selectivity and long-term stability toward nitrite oxidation in the presence of glucose and l-ascorbic (AA) was also observed at their maximum physiological concentrations, which made this novel Fe 2O 3 nanomaterial bounded with high indexed facets promising for sensing applications in medicine, biotechnology and environmental chemistry. © 2011 Elsevier Ltd. All Rights Reserved.