【摘要】：聚合物及復合材料以其優(yōu)異的性能得到廣泛應用。但在加工和使用過程中,不可避免地會產(chǎn)生微裂紋等損傷,從而導致材料的綜合性能下降并產(chǎn)生隱患。在此背景下,聚合物及復合材料自修復性能的研究應運而生�；贒iels-Alder(DA)化學的自修復材料具有制備靈活、反應條件溫和、可多次修復等特點而得到廣泛研究。但是,當前基于DA化學的自修復研究工作集中于聚合物基自修復材料及其基本物性研究,而聚合物材料自身功能有限,大大限制其實際應用。同時,針對DA體系的修復方式往往局限于加熱,修復時間長、效率較低。因此,開展基于DA化學的聚合物基復合材料的制備、應用及新型修復方式的研究意義重大。石墨烯是一種新型二維材料,具有極大的比表面積、優(yōu)異的機械性能,同時也是電和熱的優(yōu)良導體,構(gòu)建石墨烯/自修復聚合物復合材料具有重要的研究價值。本文通過引入石墨烯納米片及三維石墨烯,研究自修復復合材料的綜合性能及其在可修復柔性電子材料領域中的應用。同時,利用石墨烯對微波的吸收-轉(zhuǎn)熱作用,拓展新的高效修復方式。主要研究工作如下:1.基于DA化學的自修復酚醛環(huán)氧樹脂的制備及性能研究。利用商用的酚醛環(huán)氧樹脂,通過簡單的化學改性在環(huán)氧體系中引入呋喃基團,然后以雙馬來酰亞胺交聯(lián)得到具有優(yōu)異綜合性能和可修復性能的環(huán)氧樹脂。該材料不僅具有類似傳統(tǒng)環(huán)氧樹脂的優(yōu)異的力學性能和耐熱性能,同時具有優(yōu)異的熱可逆性質(zhì),具體表現(xiàn)為可逆的溶膠-凝膠、熱可修復及熱可溶解等特點。該材料可應用于自修復電子封裝材料等領域。2.原位聚合制備氧化石墨烯/聚氨酯自修復復合材料及性能研究。以原位聚合逐步反應制備氧化石墨烯/聚氨酯復合材料,同時引入呋喃-馬來酰亞胺體系作為自修復的單元。在較低添加量時,氧化石墨烯可以均勻分散在復合材料中,并顯著提高所制備材料的楊氏模量、斷裂強度及斷裂伸長率等性能;此外,由于大量存在由DA化學構(gòu)成的可逆六元環(huán)使得所制備的復合材料具有優(yōu)異的可修復能力,并通過原子力顯微鏡及應力-應變測試進行表征。3.石墨烯海綿的設計、制備及其在傳感器上的應用。由于強烈的π-π相互作用,石墨烯納米材料在與聚合物復合的過程中,極易產(chǎn)生團聚。本章設計制備三維石墨烯海綿作為新型納米填料并驗證其在柔性傳感器上的應用。首先,使用新型還原劑硫化銨,通過還原自組裝得到石墨烯水凝膠。然后,經(jīng)過增強、冷凍干燥等工藝制備出可壓縮-回彈的三維石墨烯,并將其應用于電阻式壓力傳感器。另一方面,利用三維石墨烯中豐富的孔洞結(jié)構(gòu),在其內(nèi)部原位聚合聚二甲基硅氧烷制備出柔性拉伸傳感器。所制備的柔性應變傳感器具有優(yōu)異的拉伸性能、高靈敏度、良好的穩(wěn)定性,并可對人體運動信號進行檢測,表現(xiàn)出了優(yōu)異的穩(wěn)定性和靈敏性。4.共價鍵連接石墨烯/聚氨酯復合材料及其在可修復柔性電子中的應用。為提高自修復材料的修復效率,本章利用石墨烯顯著的微波吸收-轉(zhuǎn)熱效應,制備基于DA化學的石墨烯復合材料。通過呋喃甲胺對氧化石墨烯進行功能化并還原制備出還原功能化氧化石墨烯(RFGO),并利用呋喃與馬來酰亞胺的共價鍵結(jié)合將RFGO引入復合材料體系中。RFGO具有優(yōu)異的分散性及高效的微波吸收-轉(zhuǎn)熱能力,不僅顯著的提高了復合材料的機械性能和熱穩(wěn)定性,也使其具有優(yōu)異的微波修復能力。此外,將三維石墨烯海綿破碎制備成三維導電網(wǎng)絡與之復合制備出可修復的柔性電子材料,并成功應用于柔性導體及檢測手指彎曲等信號的應變傳感器。最后,所制備的柔性電子材料在完全切斷后可通過微波作用5分鐘完成修復,具有在可修復柔性電子材料中的應用潛力。5.三維石墨烯基自修復柔性電子材料的制備及應用。為增強三維石墨烯與基于DA化學的自修復聚合物的結(jié)合能力,本章以呋喃甲胺作為還原劑和功能化分子制備三維石墨烯海綿。通過控制三維石墨烯海綿內(nèi)部結(jié)構(gòu),并采用灌注-原位凝膠-干燥等方式制備出具有優(yōu)異拉伸性能、熱穩(wěn)定性、低溫DA逆反應響應的三維石墨烯基自修復復合材料。所制備的材料可以直接應用于人體運動檢測的柔性應變傳感器,并可通過加熱、微波等多種方式進行修復,有望應用于可修復柔性電子中。
[Abstract]:The polymer and the composite material are widely used in the performance of the polymer and the composite material. but in the process of processing and using, the damage of micro-cracks and the like is inevitably generated, so that the comprehensive performance of the material can be reduced and a hidden danger is generated. In this background, the self-healing properties of the polymer and the composites have come into being. The self-repairing material based on Diels-Alder (DA) chemistry has the characteristics of flexible preparation, mild reaction condition and multiple repair. However, the self-repair work based on DA chemistry is focused on the polymer-based self-repairing material and its basic physical properties, and the self-function of the polymer material is limited, and its practical application is greatly limited. At the same time, the repair method for the DA system is often limited to the heating, the repair time is long, and the efficiency is low. Therefore, the preparation, application and new repair methods of the polymer-based composite based on DA chemistry are of great significance. Graphene is a novel two-dimensional material, which has a great specific surface area, excellent mechanical properties, and is also an excellent conductor of electricity and heat, and the construction of the graphene/ self-repairing polymer composite material has important research value. In this paper, the comprehensive performance of self-repairing composite and its application in the field of repairing flexible electronic material are studied by introducing the graphene nanosheet and the three-dimensional graphene. meanwhile, the absorption of the microwave by the graphene is utilized, and the novel high-efficiency repair mode is expanded. The main research work is as follows: 1. Preparation and performance of self-repairing phenolic epoxy resin based on DA chemistry. By means of a commercial phenolic epoxy resin, an epoxy group is introduced in an epoxy system by a simple chemical modification, and then an epoxy resin with excellent comprehensive performance and excellent properties can be obtained by crosslinking with a double-maleimide. The material not only has excellent mechanical property and heat resistance similar to that of the traditional epoxy resin, but also has excellent heat reversible property, and the material has the characteristics of reversible sol-gel, heat-curable and heat-soluble, and the like. the material can be applied to the fields of self-repairing electronic packaging materials and the like. Self-repair of graphene/ polyurethane self-repairing composite and its properties by in-situ polymerization. The graphene/ polyurethane composite material is prepared by the in-situ polymerization step-by-step reaction, and simultaneously the polyoxyalkylene-maleimide system is introduced as a self-repairing unit. in that low adde amount, the graphene oxide can be uniformly dispersed in the composite material, and the properties of the Young's modulus, the breaking strength and the elongation at break of the prepared material can be obviously improved; in addition, Due to the large number of reversible six-membered rings made of DA chemistry, the prepared composite material has excellent fixability and is characterized by an atomic force microscope and a stress-strain test. The design, preparation and application of graphene sponge. The graphene nano material is very easy to be agglomerated in the process of compounding with the polymer due to the strong oxygen-to-sulfur interaction. This chapter is designed to prepare three-dimensional graphene sponge as a new type of nano-filler and to verify its application on the flexible sensor. First, a new type of reducing agent is used to cure the sulfur, and the graphene hydrogel is obtained by reduction and self-assembly. then, the compressible-rebound three-dimensional graphene is prepared through the processes of reinforcement, freeze drying and the like, and is applied to a resistance type pressure sensor. on the other hand, the flexible tensile sensor is prepared by in-situ polymerization of the polydimethylsiloxanes in the internal in-situ polymerization of the polydimethylsiloxanes with a rich pore structure in the three-dimensional graphene. The prepared flexible strain sensor has excellent tensile property, high sensitivity, good stability, and can be used for detecting human body motion signals, and has excellent stability and sensitivity. The invention relates to a graphene/ polyurethane composite material which is covalently bonded and an application of the graphene/ polyurethane composite material in the repair of flexible electrons. In order to improve the repair efficiency of the self-repairing material, the graphene composite material based on DA chemistry is prepared by utilizing the remarkable microwave absorption-rotating effect of the graphene. the oxidized graphene is functionalized and reduced to prepare the reduced functionalized graphene oxide (RFGO) through the preparation of methylamine, and the RFGO is introduced into the composite material system by using the covalent bond of the disulfide bond and the maleimide. The RGO has excellent dispersibility and high efficient microwave absorption-rotating heat capacity, and not only obviously improves the mechanical property and the thermal stability of the composite material, but also has excellent microwave recovery capability. In addition, the three-dimensional graphene sponge is broken and prepared into a three-dimensional conductive network and a composite preparation of the flexible electronic material, and the flexible electronic material can be successfully applied to the strain sensor of the flexible conductor and the detection finger bending and the like. Finally, the prepared flexible electronic material can be repaired by microwave for 5 minutes after being completely cut, and has the potential of application in the repair of flexible electronic materials. Preparation and application of three-dimensional graphene-based self-repairing flexible electronic material. In order to enhance the binding ability of the three-dimensional graphene and the self-repairing polymer based on DA chemistry, the three-dimensional graphene sponge is prepared by using methylamine as a reducing agent and a functional molecule. The three-dimensional graphene-based self-repairing composite material with excellent tensile property, thermal stability and low-temperature DA reverse response response is prepared by controlling the internal structure of the three-dimensional graphene sponge, and adopting a perfusion-in-situ gel-drying method and the like. The prepared material can be directly applied to a flexible strain sensor for human motion detection, and can be repaired by a plurality of methods such as heating, microwave and the like, and is expected to be applied to the repair of flexible electrons.
【學位授予單位】：中國科學院大學(中國科學院深圳先進技術研究院)
【學位級別】：博士
【學位授予年份】：2017
【分類號】：TB33

【參考文獻】

相關期刊論文 前6條

1 龔征宇;張國平;孫蓉;汪正平;;基于非共價鍵的本征型自修復聚合物材料及其應用[J];高分子通報;2015年04期

2 江洪;王微;王輝;尹婧婧;;國內(nèi)外智能材料發(fā)展狀況分析[J];新材料產(chǎn)業(yè);2014年05期

3 李金輝;張國平;孫蓉;汪正平;;基于Diels-Alder反應的自修復聚合物材料[J];高分子通報;2014年03期

4 章明秋;容敏智;;結(jié)構(gòu)用自修復型高分子材料的制備[J];高分子學報;2012年11期

5 李思超;韓朋;許華平;;自修復高分子材料[J];化學進展;2012年07期

6 謝美然;李金欣;;微膠囊自愈合技術與自愈合材料[J];化學教學;2008年12期

相關博士學位論文 前1條

1 黃璐;石墨烯基智能材料的制備及應用研究[D];南開大學;2013年

相關碩士學位論文 前1條

1 龔征宇;基于氫鍵自修復的雙網(wǎng)結(jié)構(gòu)水凝膠的制備及性能研究[D];中國科學院深圳先進技術研究院;2016年

，

本文編號：2367982