奈米二氧化鈦於有機懸浮液中之分散機制和懸浮穩定性研究

Dispersion Mechanisms and Stabilities of Titania Nanoparticles in Organic Suspensions

郭銘書(Ming-Shu Kuo)

指導教授 ： 李嘉甄

國立臺北科技大學/工程學院/材料科學與工程研究所/碩士(2014年)

摘要

本研究旨在針對經有機矽烷偶合劑改質之奈米二氧化鈦(TiO2)粉末(商用型號：NKT90)，希望藉由添加分散劑以使粉體表面接著有分散劑之TiO2能於有機系統中獲得足夠之立體排斥能或靜電排斥能而達到被穩定分散之效果。實驗上主要先藉由FT-IR 、XPS和表面電位(Zeta Potential)等分析方法以了解NKT90的表面化學特性；再透過不同性質之油系分散劑的添加，包括具磷酸、胺基、及羧基等類分散劑，觀察NKT90與各類分散劑之間的交互作用，及其交互作用對所製備之有機懸浮液分散性質的影響。此外，根據DLVO理論以計算分散劑作用後之TiO2粒子間交互作用所產生的位能變化可進一步得知不同分散劑對TiO2的主要分散機制，而流變分析(Rheological analysis)則可驗證由不同分散劑提供之分散機制所對應的懸浮穩定性。

關鍵字

奈米 ； 二氧化鈦 ； 流變 ； 有機懸浮液 ； 分散

並列摘要

In this thesis, the selectivity for the dispersant of a commercial nano-titania (nano-TiO2) overlaid with silane was studied. Several types of dispersants with the only difference in their functional groups, including oleic acid (OA), oleyl alcohol (OL), oleyl amine (OLA) and oleyl phosphate (OP), were chosen and introduced to the organic-based suspensions of nano-TiO2 to investigate and compare their providing steric and the electrostatic repulsions. In the experiments, the surface chemistries of nano-TiO2 were identified by using the techniques of Fourier-transferred infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS) and the zeta-potentials, and the interactions between nano-TiO2 and the different dispersants and also the resulted dispersion properties of the as-prepared suspensions were assessed by analyzing the rheologies. In addition, the possible dispersion mechanisms of these dispersants for nano-TiO2 were proposed and being verified through the theoretical calculations on the potential energies caused by the addition of dispersants.

並列關鍵字

Nano ； TiO2 ； Rheology ； Organic suspension ； Dispersion

參考文獻

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