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以四溴双酚A双环氧丙基醚、四氯化硅、环氧氯丙烷为主要原料合成新型硅、氯、溴三元素协同高效阻燃剂四溴双酚A双\[三(二氯丙氧基)硅酰氧基氯丙基\]醚,并用其阻燃聚氯乙烯(PVC)。探讨了反应溶剂、温度、时间、摩尔比等对反应及产率的影响,并通过傅里叶红外光谱、核磁共振及极限氧指数等测试手段表征了产物的结构及性能。结果表明,最佳工艺条件为:以乙腈为溶剂,四溴双酚A双环氧丙基醚∶四氯化硅∶环氧氯丙烷的摩尔比为1∶2∶7;四溴双酚A双环氧丙基醚与四氯化硅在70 ℃温度下保温反应4 h,再加入环氧氯丙烷在80 ℃温度下保温反应7 h,产率达99 %;目标产物对PVC有较好的阻燃性能。 相似文献
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Transparent conductive oxide (SnO2)/organic layers/aluminum thin film sandwich structures were obtained by vacuum evaporation. The organic component was either a thin carbazole film or a bilayer. In that case, the carbazole film was deposited onto a thin insulating polymer film. The polymer used was the poly(tetrabromo‐p‐phenyleneselenide) (PBrPDSe). Photoluminescence measurements have shown that the carbazole thin films emit blue light. (I‐V) measurements have shown that the structures exhibit diode characteristics. The forward direction is obtained when the transparent conductive oxide (TCO) is positively biased. However, the reproducibility of the results obtained with a single carbazole layer is poor. It appears that the stability of the sample is improved when a thin PBrPDSe film (40 nm) is introduced between the carbazole and the SnO2. The polymer film avoids the short circuit effect. In that case, the turn‐on voltage of the diode is about 3 V, when the thickness of the carbazole film is around 250 nm and the electroluminescence appears at a voltage of about 5 V. It is shown that the thermionic effect cannot be used to explain the I‐V characteristics, which are interpreted with the help of the Fowler–Nordheim tunnel effect. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 2042–2055, 2001 相似文献
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A. Godoy Y. Tregouet S. Yapi Abe P. Molinie F. R. Diaz J. C. Bernde 《应用聚合物科学杂志》2000,78(14):2511-2517
Poly(tetrabromo‐p‐phenylenediselenide) (PBrPDSe) has been doped by IBr, H2SO3, and CH3COOH acids. The samples have been studied by X‐ray photoelectron spectroscopy (XPS) and electron spin resonance (ESR). Conductivity measurements have also been performed on pressed pellet samples. It has been shown by XPS and ESR that, after doping, positive charges are localized on Se atoms. The conductivity of the acid‐doped PBrPDSe exhibits an increase by about four orders of magnitude. However, the limit of 10−7 Ω−1 cm−1 appears difficult to overcome. This saturation effect could be attributed not only to charge localization on Se atoms but also to steric hindrance related to the substituent introduced on the backbone of the polymer. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 2511–2517, 2000 相似文献
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