双烯烃四甲基二硅氧烷环化聚合物结晶以及介电性能研究

发布时间：2018-01-04 04:17

本文关键词：双烯烃四甲基二硅氧烷环化聚合物结晶以及介电性能研究　出处：《中国科学技术大学》2017年硕士论文　论文类型：学位论文

【摘要】：现代电子器件正在不断地向小型化、柔性化和低成本化发展。未来的电子器件很可能是柔性可穿戴的,这样就要求其组成材料必须具有一定的柔韧性,并且要易于加工。而传统的无机材料由于其相对的脆性以及相对苛刻的加工条件,逐渐不能满足这些需求。聚合物虽然相对柔韧,具有良好的延展性,但是需要在其结构上引入相应的功能基团,或者进行掺杂,才能具备相应的电学性能。由于热力学熵增原理,聚合物链段自发蜷曲,会形成无定型区域,导致功能基团在空间中无序排布,严重影响聚合物材料的电学性能。所以控制聚合的有序度,使功能基团可以在空间有序排布,对研发和制备下一代聚合物电子材料至关重要。环化聚合具有提高聚合物热稳定性的优点,热稳定性对电子材料非常重要。环化聚合物的特殊拓扑结构,往往有利于分子进行自组装,有利于提高材料的有序度,并形成具有特殊理化性质的结构。这些对制备聚合物电子材料都是有帮助的。我们制备的双烯烃四甲基二硅氧烷环化聚合物就可以在一些界面上自组装形成原子晶体。在这篇工作中我们研究了双烯烃四甲基二硅氧烷环化聚合物的结晶性能以及介电性能。论文分为聚合物的合成表征、结晶性能研究和介电性能研究三个部分。(1)在合成部分,我们通过RAFT自由基环化聚合手段聚合双烯烃四甲基二硅氧烷单体(bMA与bSt),得到了双烯烃四甲基二硅氧烷环化聚合物(PbMA)以及嵌段聚合物(PbMA-b-PbSt),通过核磁共振检测证明了环化聚合的成功。(2)在结晶性能研究部分,我们摸索了 PbMA结晶薄膜的成膜条件,并通过偏光显微镜观察,确定了最佳的结晶条件。之后我们通过多种成膜手段制备PbMA薄膜,并使用X射线衍射、广角X射线散射、掠入射X射线衍射和高分辨透射电子显微观察和研究了 PbMA薄膜的结晶结构,发现其在水面自组装形成薄膜具有埃米级有序的原子晶体结构。(3)在介电性能研究部分,我们将PbMA溶液旋涂在高掺杂单晶硅片表面,再镀上电极,制备了简单的器件。通过器件测试了 PbMA薄膜的介电常数以及I-V曲线。发现PbMA有较低的介电常数,表明其有作为高频介电材料的潜力。通过I-V曲线,我们发现PbMA器件具有二极管的特性,并且其导通方向可以通过蒸镀在薄膜表面的金属电极种类(金和铝)进行控制。
[Abstract]:Modern electronic devices have been miniaturized, flexible and low cost. The development of electronic devices in the future is likely to be flexible and wearable, this requires the material must have a certain degree of flexibility, and easy processing. But the traditional inorganic materials due to its relative brittleness and relatively harsh processing conditions gradually, do not meet these needs. Although a relatively flexible polymer, has good ductility, but need the corresponding introduction of functional groups in its structure, or by doping can have electrical properties accordingly. Due to the thermodynamic entropy principle, the polymer chain will form spontaneously curled, amorphous regions, leading to functional groups in space the disordered arrangement, seriously affect the electrical properties of polymer materials. So the control of polymerization degree of order of the functional groups in the space can be arranged in order, the research and preparation of A generation of electronic polymer material is essential. Ring polymerization has the advantages of increasing the polymer thermal stability, thermal stability is very important for electronic materials. The special topology cyclopolymer, often in favor of molecular self-assembly, is conducive to improve the order of the materials, and the formation of structure with special physical and chemical properties of these preparation. Polymer electronic materials are helpful. Double olefin four methyl siloxane we prepared two cyclopolymer can in some interface self-assembly to form atomic crystal. In this blog work we studied four methyl siloxane ring two double olefin polymer crystallization properties and dielectric properties. The thesis is divided into synthesis and characterization the three part of the polymer, crystallization properties and dielectric properties were studied. (1) in the synthesis part, we through the RAFT free radical cyclization polymerization polymerization of dienes four methyl two silicon Siloxane monomers (bMA and bSt), the double four methyl siloxane ring two olefin polymer (PbMA) and block copolymer (PbMA-b-PbSt), detected by nuclear magnetic resonance proved cyclopolymerization success. (2) in the part of research of crystallization, we explored the film-forming conditions of crystallization of PbMA thin film and, through the microscope, the optimum conditions for crystallization. After we have adopted a variety of PbMA thin film coating method, and using X ray diffraction, wide angle X ray scattering, the crystal structure of grazing incidence X - ray diffraction and high resolution transmission electron microscopic observation and study of the PbMA film on the surface of the water, found its self assembly to form a film with a crystal structure. Amy order (3) on the dielectric properties of the part, we will PbMA solution spin coating on high doped silicon wafer surface, and then plated on the electrode, a simple device was fabricated. The test device through the thin PbMA Film dielectric constant and I-V curve. It is found that PbMA has a low dielectric constant, indicating that it has as high frequency dielectric material potential. Through the I-V curve, we found that the characteristics of PbMA devices with a diode, and the conduction direction can be plated on the metal electrode type film surface by evaporation (gold and aluminum) control.

【学位授予单位】：中国科学技术大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O634.41

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