【作者】 王宏；

【导师】 梁国正；

【作者基本信息】 苏州大学 ， 材料科学与工程， 2016， 硕士

【摘要】 电子信息、绝缘材料、新能源和航空航天等尖端领域的不断发展很大程度上取决于应用于其中材料的性能。氰酸酯(CE)树脂是耐热热固性树脂的代表,其最大的性能优势是在较宽频率范围内具有优异的介电性能。基于这些优点,CE固化树脂在上述领域中显示出巨大的应用前景。但是高固化温度和高脆性是热固性树脂的现有不足。建立一种同时克服这两大不足的方法,获得兼具低固化温度和高韧性的改性CE树脂一直是材料领域的重要研究内容。本文基于以上问题展开,将氧化石墨烯(GO)和锰离子金属有机骨架(MnMOF)进行掺杂,分别采用水热合成法和机械搅拌法制备了不同粒径以及不同Mn2+/配体比例的新型氧化石墨烯/锰离子金属有机骨架杂化体(GO/MnMOF),并对其结构进行了分析表征。研究表明这种杂化体不是GO与MnMOF的简单物理共混,而是两者之间以化学键相连,杂化体表面的有机基团能够使之与CE树脂良好的结合,从而提高其在CE树脂中的分散性。在此基础上,为了达到更佳的催化增韧效果,本文又制备了超支化聚硅氧烷氧化石墨烯/锰离子金属有机骨架(HBPGO/MnMOF),然后将这两种兼备催化和增韧作用的杂化体来改性CE树脂。详细探讨了 GO/MnMOF2(m)(由机械搅拌法制备的Mn2+与有机配体比例为1:1的GO/MnMOF)和HBPGO/MnMOF对CE的固化反应性的影响。制备了一系列改性树脂,并研究了其介电性能、热性能和力学性能等关键性能。研究表明GO/MnMOF2(m)及HBPGO/MnMOF的加入能够大幅度降低CE的固化反应温度,加入0.5wt%GO/MnMOF2(m)便能使改性体系的后处理温度由240℃降至220℃,其催化剂的作用不是GO和MnMOF2(m)的简单组合,而是表现出显著的协同催化效果。改性剂的加入能够显著地提升固化树脂的综合性能,包括热稳定性、介电性能、韧性和刚性。通过加入GO/MnMOF2(m)或HBPGO/MnMOF的改性方法,为解决CE树脂的两大瓶颈做出了巨大贡献,改性树脂这些优异的性能证明GO/MnMOF2(m)及HBPGO/MnMOF是一种高效的多功能改性剂。本文通过控制交联网络结构显著提升CE树脂综合性能的机理为发展高性能热固性树脂提供了一种新的方法。更多还原

【Abstract】 The development of cutting-edge fields,such as electronic information,electrical insulation,new energy and aerospace,etc.,is greatly dependent on the performances of materials.Cyanate ester(CE)resin is a representative of thermally resistant thermosetting resins,of which the biggest feature is extremely low and stable dielectric constant and loss over a wide frequency range,and thus showing great potential in applying for these fields.However,as other thermosetting resins,CE resin also has two bottlenecks,they are high curing temperature and big brittleness.Therefore,developing new method to fabricate high performance resins with low curing temperature and high toughness has been one important topic of materials’ researchesBased on above issues,a series of novel hybrids(GO/MnMOF)with different partical sizes and Mn2+/ligand ratio,consisting of GO and manganese-centered metal organic framework(MnMOF),were synthesized by hydrothermal synthesis method and mechanical stirring method.Their structures were characterized.Results show that these hybrids consist of GO and MnMOF with chemical bonding,but are not a simple physical blend of GO and MnMOF.The organic groups on the surfaces of hybrids provide good interfacial adhesion between hybrids and CE resin,this also improves the dispersion of hybrids in CE matrixBesides,in order to achieve better catalytic and toughening effects,hyperbranched polysiloxane modified graphene oxide/manganese-centered metal organic framework hybrids(HBPGO/MnMOF)were also prepared.Either GO/MnMOF2(m)(GO/MnMOF synthesized by mechanical stirring method with the ratio of Mn2+ to organic ligand is 1:1)or HBPGO/MnMOF hybrids were used to modify CE resin.The influences of GO/MnMOF2(m)and HBPGO/MnMOF on the curing of CE were discussed.A series of modified CE resins were also prepared and their dielectric,thermal and mechanical properties were studied.Results show that the curing temperature can be significantly reduced by adding GO/MnMOF2(m)or HBPGO/MnMOF.The addition of only 0.5 wt%of GO/MnMOF2(m)can reduce the postcuring temperature of CE from 240℃ to 220℃and there is a synergistic catalytic effect on the curing of CE rather than simple combination of GO and MnMOF2(m).Adding these modifiers can also improve the overall performances of cured resin,including thermal resistance,dielectric properties,toughness and rigidity.The modified methods by adding GO/MnMOF2(m)or HBPGO/MnMOF make tremendous progress for overcoming the two bottlenecks of CE resin.These excellent performances of modified CE resins prove that GO/MnMOF2(m)and HBPGO/MnMOF are effective and multifunctional modifiers.The mechanism for significantly improve the overall performances of CE resin through controlling the crosslinked structure developed in this thesis provides a new approach to develop high performance thermosetting resins更多还原