奈米中空及核殼材料之製備方法研究

Preparations of nano hollow and core-shell materials

黃思絜(Szu-Chieh Huang)

指導教授 ： 李嘉甄

國立臺北科技大學/工程學院/材料及資源工程系研究所/碩士(2014年)

https://doi.org/10.6841/NTUT.2014.00358

摘要

本研究以奈米複合粒子為研究主軸，分為奈米核殼結構與微膠囊材料兩大部分。第一部分我們將奈米貴金屬以核殼結構的概念製備成奈米中空銀球，減少奈米貴金屬運用在電子產品上之高成本問題。實驗中利用簡單且高效率的化學合成法，以葡萄糖作為還原劑在聚苯乙烯微球表面還原銀，製備奈米銀金屬包覆聚苯乙烯微球，再進一步利用有機溶劑去除核心材料後形成奈米中空銀球。然而，由此法所合成之奈米中空銀球在未進行表面改質之前，在水溶液中的分散穩定性不佳，為改善此現象，我們將在合成過程中添加分散劑進行表面改質，使粉體表面產生互斥作用力，以達到良好之分散穩定性，提高粉末應用價值。
第二部分主要利用尿素與甲醛聚合而成之尿醛樹脂作為微膠囊之殼層材料，並探討兩種不同合成方式所製備出之微膠囊的差異性，經由實驗條件的改變來調整微膠囊的情形，包含轉速改變、內容物替換與實驗配方調整等等，逐步改善微膠囊製程以期得到表面光滑、形貌完整且強度穩定之尿醛樹脂微膠囊；並嘗試在所包覆之核心材料中添加奈米銀粒子，製備出含有奈米銀粒子之微膠囊，增加微膠囊未來發展的應用範圍。最後將所得到之微膠囊核心材料添加奈米粒子，提高微膠囊強度，並使微膠囊能有更廣泛的運用。

關鍵字

奈米 ； 核殼結構 ； 中空粒子 ； 微膠囊

並列摘要

This thesis primarily focuses on the investigations about two structural composite powder materials, the polystyrene-silver core-shell (PS@Ag) structured materials and the urea-formaldehyde resin based (PUF) microcapsules. To break through the application limitations of noble silver particles, such as its high cost and its difficulty of less being compatible with other materials, an idea about preparing hollow-structured silver particles was proposed. The hollow silver particles were fabricated via the method of using glucose as the reduction agent for reducing silver (Ag) on the surface of polystyrene (PS) particles at the first step. Then the hollow Ag can be easily obtained by removing the core PS by dissolving it in the organic solvent. However, the as-prepared hollow Ag particles are too hydrophilic to be dispersed in aqueous-based system. Therefore, some appropriate dispersants were added during the particle preparation process to modify the particles’ surface to improve the dispersion property.
On the other hand, the other subject in this thesis investigates the effects of different experimental procedures and parameters on the resulted morphologies of synthesized PUF microcapsules. In this research, some experimental conditions including reaction parameters and species of core materials were modified and adjusted in order to have more consolidated microcapsules with improved mechanical strength and better surface microstructure. In addition, we also tried to have nanoparticles, such as Ag or inorganic oxides, embedded in the polymeric shell of PUF microcapsules in order to increase the application potentials of capsules in the future.

並列關鍵字

nano ； core-shell ； hollow particles ； microcapsules

參考文獻

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