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聚对苯二甲酸丙二醇酯作为新型聚酯材料,具有非常优良的性能,但其易燃性很大的限制了它的应用范围。为了提高对苯二甲酸乙二醇酯的阻燃性能,本文以无卤膨胀型EPFR-300A为阻燃改性剂,马来酸酐接枝聚烯烃(POE-g-MAH)弹性体为增韧剂,对聚对苯二甲酸丙二醇酯树脂(PTT)进行阻燃改性。通过热重分析仪(TGA)、示差扫描量热仪(DSC)、扫描电子显微镜(SEM)、力学性能等技术手段研究了阻燃剂和增韧剂对PTT树脂力学、热学和阻燃性能的影响。结果表明,增韧剂POE和POE-g-MAH的添加提高了PTT树脂的综合力学性能。当质量分数相同时,POE-g-MAH对PTT树脂的增韧效果要优于POE,且当POE-g-MAH质量分数为7%时,综合力学性能最佳。当添加相同质量分数增韧剂,EPFR-300A质量分数达到20%时,阻燃PTT材料阻燃性能最佳,极限氧指数(LOI)达到28.0%,垂直燃烧阻燃等级达到UL94 V-0级。EPFR-300A阻燃剂与PTT树脂间相容性良好,可以有效地促进PTT树脂成炭并提高材料的阻燃性能。 相似文献
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Enhanced absorption properties of ordered mesoporous carbon/Co-doped ordered mesoporous carbon double-layer absorbers
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Ordered mesoporous carbon (OMC) and metal-doped (M-doped) OMC composites are prepared, and their electromagnetic (EM) parameters are measured. Using the measured EM parameters we calculate the EM wave absorption properties of a double-layer absorber, which is composed of OMC as an absorbing layer and M-doped OMC as the matching layer. The calculated results show that the EM wave absorption performance of OMC/OMC-Co (2.2mm/2.1mm) is improved remarkably. The obtained effective absorption bandwidth is up to 10.3 GHz and the minimum reflection loss reaches 47.6 dB at 14.3 GHz. The enhanced absorption property of OMC/OMC-Co can be attributed to the impedance match between the air and the absorber. Moreover, it can be found that for the absorber with a given matching layer, a larger value of -tanδε (= tan δε absorbing tan δε matching ) can induce better absorption performance, indicating that the difference in impedance between the absorbing layer and the matching layer plays an important role in improving the absorption property of double-layer absorbers. 相似文献
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