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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

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. Source

Xia C.,Capital Medical University | Xia C.,State Key Laboratory of Chemical Resource Engineering | Yanjun X.,Beihang University | Ning W.,Beihang University
Electrochimica Acta

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. Source

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

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. Source

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.

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. Source

Sun F.,State Key Laboratory of Chemical Resource Engineering | Sun F.,Beijing University of Chemical Technology | Hu Y.,Beijing University of Chemical Technology | Du H.-G.,State Key Laboratory of Chemical Resource Engineering | Du H.-G.,Beijing University of Chemical Technology
Journal of Applied Polymer Science

MQ silicone resins, which represent a broad range of hydrolytic condensation products of monofunctional silane (M) and tetrafunctional silane (Q), were synthesized by reaction of water glass with hexamethyldisiloxane. The optimum reaction time and the optimal reaction temperature is 30 min and 30-40°C, respectively. Concentrated hydrochloric acid is the best one among those catalysts tested. In large-scale experiments (420-1680 mL), the favorable feeding order is catalyst first, and then water glass, the mixture of hexamethyldisiloxane and ethanol last and most MQ silicone resin was observed. The structure of MQ silicone resin was characterized by FT-IR and GPC spectra. The MQ silicone resin shows narrow molecular weight distribution and the number average molecular weight of MQ silicone resin is 2917. The silicone pressure sensitive adhesive prepared from as-synthesized MQ resin has good tack (29#) and 180° peel adhesion (5.630N/20 mm). Copyright © 2012 Wiley Periodicals, Inc. Source

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