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.
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.
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.
Bai F.,Southwest University of Science and Technology |
Huang J.,Sichuan EM Technology Co. |
Zhi X.,Sichuan EM Technology Co. |
Ma H.,Southwest University of Science and Technology |
And 2 more authors.
Gaofenzi Cailiao Kexue Yu Gongcheng/Polymeric Materials Science and Engineering | Year: 2016
A highly branched benzoxazine (II) based on cyclotriphosphazene was synthesized by self-made hexa (4-hydroxyphenoxy) cyclotriphosphazene (I), aniline and formaldehyde in a solvent of toluene, the yield is 68.9%. The structures and properties of (II) and its cured resin (III) were characterized by FT-IR, 1H-NMR, DSC, TGA, limiting oxygen index (LOI) and vertical burning test. In addition, the properties of (II) and III were studied in comparison with that of common benzoxazine. The results show that the initial temperature and peak temperature of ring-opening polymerization are 186.0℃ and 235.4℃ respectively, which are lower than those of common benzoxazine. Furthermore, the temperatures of (III) at 5% and 10% mass loss are 344.1℃ and 392.7℃ respectively, and the char yield of (III) is 64.97% at 800℃. Moreover, the LOI of (III) is 43.5% and (III) can also achieve a UL94 V-0 rating in vertical burning test. These results suggest that (III) has more excellent thermostability and flame retardancy than common benzoxazine and can be used in flame retardant area which has higher requests. © 2016, Chengdu University of Science and Technology. All right reserved.
Wei C.,Guilin University of Technology |
Zeng S.,Guilin University of Technology |
Zeng S.,Sichuan em Technology Co. |
Tan Y.,Guilin University of Technology |
And 3 more authors.
Advances in Materials Science and Engineering | Year: 2015
The renewable cationic polyelectrolyte chitosan (CH) and anionic nanomontmorillonite (MMT) layers were alternately deposited on the surface of sisal fiber cellulose microcrystals (SFCM) via layer-by-layer (LBL) self-assembly method. The structure and properties of the composites were characterized by zeta potential, thermal gravimetric analysis (TGA), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), Fourier transform infrared spectrometer (FTIR), microcalorimeter (MCC), and so forth. The zeta potential results show that the cellulose microcrystalline surface charge reversed due to the adsorption of CH and MMT nanoplatelets during multilayer deposition. MMT characteristic diffraction peaks appear in XRD patterns of SFCM(CH/MMT)5 and SFCM(CH/MMT)10 composites. Additionally, FESEM reveals that the SFCM(CH/MMT)10 surface is covered with a layer of material containing Si, which has been verified by elemental analysis. TGA results show that the initial decomposition (weight loss of 5%) temperature of SFCM(CH/MMT)5 is increased by 4°C compared to that of pure SFCM. On the other hand, carbon residue percentage of SFCM(CH/MMT)10 is 25.1%, higher than that of pure SFCM (5.4%) by 19.7%. Eventually, it is testified by MCC measurement that CH/MMT coating can significantly reinforce the flame retardant performance of SFCM. © 2015 Chun Wei et al.