【作者】 王敏；

【导师】 武湛君；

【作者基本信息】 大连理工大学 ， 工程力学， 2015， 硕士

【摘要】 众所周知,环氧树脂因其优异的性能而被广泛应用于各个方面,但是另一方面因为其本身阻燃性能较差的原因,其极限氧指数只有19.8%,这限制了它在一些领域的应用。同时如果高分子材料的阻燃性能足够好,而力学等性能达不到要求,在特定条件下也不会得到广泛的应用。本篇论文旨在研究提高环氧树脂的阻燃性的同时又保证不严重破坏其物理机械性能。采用双酚A型环氧树脂E-51,固化剂采用4,4-二氨基二苯砜(DDS)。通过分别添加无机阻燃剂氢氧化镁阻燃剂、气相纳米二氧化硅和有机阻燃剂磷酸三苯酯(TPP)三种阻燃剂来制备并改性环氧树脂,并通过力学拉伸实验、扫描电镜SEM、差示扫描量热(DDS:Differential Scanning Calorimetry)分析、氧指数等多种手段来表征其力学性能、热性能及阻燃性能,其中无机阻燃剂氢氧化镁和气相纳米二氧化硅的表面用硅烷偶联剂KH-550进行改性处理。通过研究分析发现,采用硅烷偶联剂KH-550进行表面改性,有助于粒子的分散,改善粒子与基体的相容性,同时也有助于改善加工工艺性。通过对比三种添加型阻燃剂发现：经过氢氧化镁阻燃剂、气相纳米二氧化硅和磷酸三苯酯(TPP)改性后的环氧树脂的拉伸强度分别提高了8.3%、23%、52%；断裂伸长率分别提高了131.9%、31%、328.7%。对比发现添加有机阻燃剂磷酸三苯酯(TPP)对环氧树脂的力学性能改善效果最佳。通过比较三种添加型阻燃剂,环氧树脂经氢氧化镁阻燃剂改性和气相纳米二氧化硅改性后的玻璃态转化温度(Tg)分别提高了40℃左右,而经过有机阻燃剂磷酸三苯酯(TPP)改性的环氧树脂的玻璃态转化温度(Tg)却呈现下降趋势。通过比较三种添加型阻燃剂,经过氢氧化镁阻燃剂、气相纳米二氧化硅和磷酸三苯酯(TPP)改性后的环氧树脂的氧指数分别提高了43.4%、26.%、66.2%,LOI值分别达到28.4,25,32.9。综合评价发现环氧树脂经过添加有机阻燃剂磷酸三苯酯(TPP)改性的效果在三种添加型阻燃剂中表现最佳。最终得出,添加型阻燃剂改性环氧树脂的改性效果并不是添加含量越高效果越好,每种阻燃剂的最佳添加含量都不一样。综合考虑,在保证力学性能不被严重破坏的基础上,氢氧化镁阻燃剂添加含量为20wt%的时候改性效果最佳；气相纳米二氧化硅添加含量为3wt%的时候改性效果最佳；有机阻燃剂磷酸三苯酯(TPP)的添加含量质量为40wt%的效果最佳。更多还原

【Abstract】 As is known to all, due to its excellent properties, epoxy resin have been widely used in many fields, however, its limit oxygen index is only 19.8%, which limits its application in some fields. Therefore, this paper aims to improve the flame retardancy of epoxy resin, at the same time, without serious damage to the relevant aspects of the physical and mechanical properties. In this paper, the type of epoxy resin is E-51, and the curing agent is 4-4’-Diaminodiphenyl sulfone (DDS). By adding inorganic flame retardant Mg(OH)2, nano silica and organic flame retardant TPP to the resin matrix to prepare the modified epoxy resin. Through mechanical tensile test, scanning electron microscope (SEM), differential scanning calorimetry (DDS), and oxygen index to characterize its performance, meanwhile, the flame retardant Mg(OH)2 and nano silica particles were surface modified by 3-Glycidoxypropyltrimethoxy silane (KH-550).Through analysis, we found that the surface modified by silane coupling agent KH-550 is beneficial for the dispersion of the particles and the compatibility of the particles and the matrix, also beneficial for the processing technology.Experimental results indicate that the tensile strength increase up to 8.3%,23% and 52% respectively; elongation at break increase up to 131.9%,31%, and 328.7% respectively. We found that through adding the organic flame retardant TPP is the better way to improve the mechanical properties compared to other two flame retardants.The addition of the Mg(OH)2 and SiO2 particles can remarkably enhance the glass transition temperatures of the resultant composites, compared to the neat epoxy resin. The glass transition temperatures increase up to about 40℃.However, with the addition of TPP, the glass transition temperature was on a declining line curve.The limit oxygen index increase up to 43.4%,26% and 66.2%, respectively. This indicated that the organic flame retardant TPP had a better flame retardant effect on epoxy resin.The opinion of more content of flame retardant better effect is wrong. Each flame retardant’s best content is different. In this paper, considering the comprehensive properties, the best content of the three flame retardants are 20wt%,3wt% and 40wt%, respectively.更多还原