本文選題：氧化石墨烯　切入點：功能化　出處：《華南理工大學》2015年碩士論文　論文類型：學位論文

【摘要】：本文以三聚氯氰(TCT)、己二胺(HDM)和4,4′-二氨基二苯基甲烷(DDM)為原料,通過調控溫度合成出兩種帶有四個碳氯鍵的高活性分子TCTHDM和TCTDDM,采用傅立葉紅外、核磁共振的方法對合成產物進行了結構表征。然后以氧化石墨烯(GO)為前驅體,通過一步法在表面分別接枝上兩種有機小分子TCTHDM和TCTDDM,成功制備出兩種功能化氧化石墨烯(TCTHDM-GO和TCTDDM-GO),通過紅外光譜、拉曼光譜、X射線衍射、掃描電子顯微鏡分析了功能化氧化石墨烯的結構和表面形貌,通過熱失重分析探究了其熱穩(wěn)定性,并對兩種功能化氧化石墨烯的分散性進行了探討。在接枝上兩種小分子后,石墨烯的熱穩(wěn)定性比氧化石墨烯有了提高,片層之間由于引入了有機小分子,無序性和層間距都有所增大。采用非等溫DSC法研究了功能化氧化石墨烯對環(huán)氧樹脂固化行為的影響,隨著石墨烯添加量的增大,固化體系達到最大熱釋放速率的溫度越低,固化體系總釋放熱也越少,而在同一溫度下所對應的轉化率卻越高,分別通過Kissinger和Ozawa兩種方法計算了固化反應的活化能,發(fā)現比純環(huán)氧樹脂的低,說明功能化氧化石墨烯的加入對環(huán)氧樹脂的固化行為有一定的催化作用。通過熱失重分析發(fā)現,功能化氧化石墨烯不會改變兩種復合材料體系的熱分解歷程。利用DMA法研究了在不同功能化氧化石墨烯含量下兩種固化體系TCTHDM-GO/Epoxy和TCTDDM-GO/Epoxy的儲能模量、損耗因子和玻璃化轉變溫度的變化,發(fā)現添加一定量的TCTHDM-GO和TCTDDM-GO能促進環(huán)氧樹脂交聯,提高環(huán)氧樹脂基體的儲能模量及玻璃化轉變溫度。當添加TCTHDM-GO的質量分數為1.4%時的復合材料,其儲能模量達到最大,提高了0.475GPa,而當質量分數為1.0%時,玻璃化轉變溫度出現極大值,為168.2℃。對于TCTDDM-GO的環(huán)氧樹脂復合材料,儲能模量在質量分數為1.0%處達到最大值,在質量分數為1.4%時,玻璃化轉變溫度出現極大值,提高了6.5℃。最后,對復合材料的力學性能進行了測試分析,發(fā)現少量的功能化氧化石墨烯的加入可提高復合材料的力學性能,拉伸強度最大提升了43%,彎曲強度最大提升了24%,抗沖擊強度最大提升了111%。
[Abstract]:In this paper, two kinds of highly active molecules (TCTHDM and TCTDDM) with four carbon-chlorine bonds were synthesized by controlling temperature by using trimelamine, hexanediamine (HDM) and 4Amino-diphenylmethane (DDM) as raw materials, and Fourier transform infrared spectroscopy (FT-IR) was used. The synthesized products were characterized by NMR. Then graphene oxide (GOO) was used as the precursor. Two kinds of functional graphene oxide (TCTHDM-GO) and TCTDDM-GOA (TCTDDM-GOA) were successfully prepared by one-step grafting of two kinds of organic small molecules (TCTHDM and TCTDDM) on the surface, respectively. The two kinds of functionalized graphene oxide TCTHDM-GO and TCTDDM-GOA were prepared by IR, Raman spectra and X-ray diffraction. The structure and surface morphology of functionalized graphene oxide were analyzed by scanning electron microscope (SEM). The thermal stability of functional graphene oxide was investigated by thermogravimetric analysis. The thermal stability of graphene is better than that of graphene oxide. The influence of functionalized graphene oxide on the curing behavior of epoxy resin was studied by non-isothermal DSC method. With the increase of the amount of graphene, the temperature at which the maximum heat release rate of the curing system reached the maximum heat release rate was lower. The lower the total heat release of curing system is, the higher the corresponding conversion is at the same temperature. The activation energy of curing reaction is calculated by Kissinger and Ozawa, respectively, and it is found that the activation energy of curing reaction is lower than that of pure epoxy resin. The results show that the addition of functionalized graphene oxide can catalyze the curing behavior of epoxy resin. The thermal decomposition mechanism of the two composites was not changed by functionalized graphene oxide. The storage modulus of TCTHDM-GO/Epoxy and TCTDDM-GO/Epoxy in two curing systems with different content of graphene oxide were studied by DMA method. With the change of loss factor and glass transition temperature, it is found that adding a certain amount of TCTHDM-GO and TCTDDM-GO can promote the crosslinking of epoxy resin, improve the storage modulus and glass transition temperature of epoxy resin matrix. The storage modulus reached the maximum, increased by 0.475 GPA, and the glass transition temperature reached the maximum of 168.2 鈩，

本文編號：1639769