Preparation and Characterization of Colorless Polyimide / Two - dimensional nanosheet composite film
| Autor: | Chi-Wei Chung, 鐘琦瑋 |
|---|---|
| Rok vydání: | 2014 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 102 In this study the asymmetric structure of the aromatic diamine (3,4 '-ODA) monomers, alicyclic dianhydride (BCDA) monomer with a mixed solvent (DMAc and GBL) .With one-step synthesis of colorless polyimide film. By adding graphene oxide (GO), covering the aluminum hydroxide of graphene oxide(Al-GO), two-dimensional alumina nano sheet (Alns) to prepare colorless and good water vapor barrier properties of polyimide nanocomposite films. Part I: Preparation of two-dimensional alumina nano sheet. This study using sol-gel method, covering aluminum hydroxide on the GO surface prepared Al-GO, and using high-temperature decomposition of the GO successfully prepared Alns. Identification of binding energy in XPS, At Al-GO and Alns alumina can be found in 74.8ev of a binding energy in Al2p, and all three are confirmed sheet structure by TEM, using EDX analysis Alns does contain Al and O with TEM mutual reflection, covering the aluminum hydroxide content of graphene oxide explore different proportions to be respectively 1:3, 1:1.5, 1:1 (AlIP: GO) of Al-GO, by SEM, images as the ratio increases, the degree of surface wrinkles vary GO, TGA test different ratios of Al-GO heated in air to 800 ℃, can be found in the highest proportion (1:1) of the Al-GO has a maximum amount of residue.Then the highest proportion (1:1) of the Al-GO to explore different temperatures, respectively, 600 ℃, 650 ℃, 700 ℃, finally from the SEM imagesat 700 ℃ high temperature Alns have a more complete burning solution sheet structure. Part II: Preparation of colorless polyimide / two-dimensional nano sheet composite films This study is the first part of the three kinds of two-dimensional sheet nanostructures were added in different proportions in the colorless polyimide, after adding three different two-dimensional sheets on the thermal properties of nanostructures; good thermal stability can be maintained(Td5%>400℃), and dimensional stability (coefficient of thermal expansion, CTE) are obviously decreased; with increasing the mechanical properties are also increased significantly, water vapor transmission rate (WVTR) analysis can be observed, PI / Alns series have the most excellent barrier properties in the same amount of 1 wt%, PI / Alns the WVTR was 6.9 g-mil / m2-day, PI / GO and PI / Al-GO can be decreased to 10.6 and 13.8 g-mil / m2-day, relative to the pure polyimide (181.3 g / m2-day), the decreased high 96.1%. Water absorption tests to PI / Alns 1wt% has the lowest water absorption (3.3%), relative to the pure polyimide (7.3%), decreased by about 54.8%. After adding GO 1wt% and Al-GO 1wt%, the optical penetration has significantly decreased to 90.3% and 85.0%, after adding Alns 1wt%, remains in excellent optical transmittance of 96.3%. This proves add Alns in colorless polyimide, the impact on the optical transmittance is very small. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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