PMMA奈米複合材料與奈米級蒙脫石溶液的製備及性質分析

Abstract

本論文主要分成兩部分，第一部份是採用先前實驗室製備幾丁聚醣/蒙脫石奈米複合材料的技術，並改良一些實驗步驟，製備奈米級矽酸鹽幾丁聚醣溶液，並嘗試將其當作PMMA乳化聚合的乳化劑，以期藉由脫層蒙脫石改善PMMA的性質。 第二部份則為本論文的重點，以過硫酸鉀改質後的蒙脫石當作PMMA乳化聚合的起始劑，藉由聚合反應時產生之大量能量，使蒙脫石脫層，則可以製成PMMA奈米複合材料。另一方面，利用甲苯經由萃取將PMMA乳液移除，可得到奈米級矽酸鹽溶液。藉由TGA、DSC、TMA和MHT的分析，可得知藉由此法所得之PMMA奈米複合材料的熱性質跟機械性質皆有明顯的改善，由此可得知脫層蒙脫石已均勻分散於高分子乳液中。最後藉由TEM和AFM的分析，將脫層後之蒙脫石的大小尺寸確定出來，長與寬皆約為100 nm ~ 3000 nm，而厚度約為6~8 nm。

This thesis contains two parts. In the first part, we adopted the previous method to produce the chitosan/montmorillonite nanocomposites. With some modification, we obtained a nanoscale silicate chitosan solution (NSCS) and it can be used as emulsifier for PMMA emulsion polymerization to improve the properties of PMMA. In the second part, we employed KPS-modified montmorillonite as an initiator for PMMA emulsion polymerization. During polymerization, montmorillonites were exfoliated and intermingled with PMMA in polymer particles to form a will-dispersed nanocomposite. On the basis of the analysis of TGA, DSC, TMA, and MHT, the thermal and mechanical properties of such-formed nanocomposite have been significantly improved. On the other hand, nanoscale silicate solution (NSS) can be afforded after removal of PMMA by extraction with toluene. Both length and width of exfoliated montmorillonite are about 100 ~ 3000 nm and the thickness of exfoliated montmorillonite is about 6 ~ 8 nm which are confirmed by TEM and AFM analysis.