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Mianyang, China

Dong Y.,Southwest University of Science and Technology | Wang H.,Southwest University of Science and Technology | Wang W.,Changhong Electrical Co. | Liang Q.,Sichuan Em Technology Co | And 3 more authors.
Kuei Suan Jen Hsueh Pao/Journal of the Chinese Ceramic Society | Year: 2013

Eu3+ doped CaCO3 phosphor (CEP) was prepared by a microwave method. The CEP coated with stearic acid (c-CEP) was added into polypropylene (PP). The structure and physicochemical properties of PP/c-CEP composites were characterized by photoluminescence and photoluminescence excitation spectroscopy, scanning electron microscopy and differential scanning calorimetry, respectively. The results demonstrate that c-CEP can be dispersed in the PP composites. Compared to PP/c-CEP and CEP, the luminescent intensity of c-CEP is stronger. The luminescent intensity of PP/c-CEP increases with the increase of c-CEP. The maximal emission peaks of CEP and PP/c-CEP appear at 614 nm, corresponding to the electric-dipole transition 5D0→7F2 of Eu3+ ion, and showing red under UV light. Moreover, the mechanical properties of PP/c-CEP composite unchanged. Compared to the pure PP, a faster crystallization rate, a higher melting point and a lower crystallization degree in the PP/c-CEP composite were detected.


Sichuan EM Technology Co. | Date: 2009-08-25

Insulating materials of mica; insulating materials.

Li Y.,Southwest University of Science and Technology | Li Z.-Q.,Southwest University of Science and Technology | Huang H.-C.,Sichuan Em Technology Co | Pei C.-H.,Southwest University of Science and Technology
Hanneng Cailiao/Chinese Journal of Energetic Materials | Year: 2013

A kind of antistatic nitrocellulose (NC) membrane was successfully prepared via the liquid phase mixing complex method using NC as raw materials and selecting carbon series conductive filler to NC. The antistatic performance, mechanical property and microstructure of antistatic NC membrane were characterized by high resistance meter, static sensitivity tester, electronic universal testing machine and field emission scanning electron microscope, respectively. The results show that when 1.0% conductive filler is added, the surface resistivity and volume resistivity of the antistatic NC membrane are 2.2×109 Ω and 7.5×109 Ω·m. respectively. Compared with unmodified NC, the surface resistivity and volume resistivity of the antistatic NC membrane are reduced by 6 orders of magnitude and 3 orders of magnitude, respectively. The electrostatic spark sensitivity of the antistatic NC membrane is 2.31 J. Compared with unmodified NC the electrostatic spark sensitivity of the antistatic NC membrane is increased by 14%, revealing that the antistatic NC membrane has better antistatic performance. The mechanical property parameters of the antistatic NC membrane are improved, showing that the addition of conductive filler does not degrade the mechanical property of NC. The formation of interlaced conductive networks in the products is conduciue to the electrostatic charge dissipate.

Li X.-C.,Southwest University of Science and Technology | Wu X.-M.,Sichuan Em Technology Co | Tang A.-B.,Southwest University of Science and Technology | Tang A.-B.,Sichuan Em Technology Co
Xiandai Huagong/Modern Chemical Industry | Year: 2010

Dicyclopentadien diepoxide (ERL-4207) is synthesized by epoxidation of dicyclopentadiene (DCPD) with hydrogen peroxide and water in the presence of catalyst of quaternary ammonium heteropolyphosphato tungstates in a microemulsion. The conversion rate of DCPD and the selectivity of ERL-4207 are 99.99% and 97.47%, respectively. This process has the advantages of mild conditions, simple operation, easy isolation, high yield and environment-friendliness. The catalyst can be easily recycled and reused for several times efficiently.

Li X.,Southwest University of Science and Technology | Liao D.,Southwest University of Science and Technology | Ma H.,Southwest University of Science and Technology | Xu K.,Sichuan Em Technology Co | Tang A.,Sichuan Em Technology Co
Advanced Materials Research | Year: 2012

An intumescent flame retardant (IFR) system containing phosphorus-silicon (EMPZR) and ammonium polyphosphate (APP) was used to improve the flame retardancy of poly(ethylene-co-vinyl acetate)(EVA). The influence of EMPZR contents on the flame retardance of EVA/EMPZR/APP composites has been studied. It was found that the reasonable mass ratio of EMPZR/APP in EVA/EMPZR/APP composites is 20/20, whose limiting oxygen index (LOI) value was improved from 19.0 for EVA to 28.6, and the burning grading reached to UL-94 V-0. The thermal behavior of EVA and IFR-EVA was investigated by dynamic thermo gravimetric analysis (TGA) at different heating rates and then the thermal degradation activation energies of EVA and IFR-EVA were determined by using Flynn-Wall-Ozawa method. Meanwhile, morphology of the char residue obtained from burning IFR-EVA in LOI test was studied through the scanning electron microscopy SEM observation, the rich compact char layer in which could explain the good flame retardance and the synergistic effect between EMPZR and APP. © (2012) Trans Tech Publications, Switzerland.

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