以前置物法與同時聚合法包覆碳氫化合物之研究

本研究以溶膠-凝膠法（sol-gel method）製備碳氫化合物微膠囊，利用矽氧烷化物的溶膠-凝膠反應和乳化技術將可耐高溫之材質包覆在碳氫化合物的表面，形成緻密之無機包覆層以改善相轉移材料的熱性質，進而達成避免碳氫化合物在加工時熱處理所造成的損失情形。本實驗分為前置物以及同時聚合法兩部份。在前置物法的部份，是將無機系統中之四乙氧基矽烷、乙醇及水先在酸性環境下進行水解-縮合反應後，再與含相轉移材料之有機系統進行後續反應。而在同時聚合法部份，是同時導入有機及無機部份，藉由四乙氧基矽烷在有機石蠟的油滴表面進行水解縮合反應，而形成緻密的網狀結構。實驗所得之碳氫化合物-石蠟微膠囊產物性質以微差掃描熱分析儀（DSC）、熱重分析儀（TGA）以及掃描式電子顯微鏡（SEM）等儀器進行分析，由儀器分析的結果得知利用同時聚合法可成功地製備出產率高達98%之具有良好的矽包覆石蠟微膠囊產物，該產物之熱裂解溫度不但由原本的250℃提升至310℃，且其石蠟包覆率在經由280℃、3分鐘之處理後仍高達66wt%以上。

關鍵字

溶膠-凝膠法；四乙氧基矽烷；碳氫化合物；前置物法；同時聚合法

並列摘要

The microcapsules containing hydrocarbon were prepared by the sol-gel method. The sol-gel reaction of siloxane and the emulsion technique were utilized to encapsulate the hydrocarbon. Then the high temperature durable material was coated on the surface of hydrocarbon. For avoiding the weight loss of hydrocarbon during heat treatment process, this method was used to form a dense inorganic encapsulated film to improve the heat durable properties of the phase change material. There are two works were administered, including precursor and in-situ process for sol-gel method. In the part of precursor, the inorganic system-tetraethylorthosilicate (TEOS), ethanol and water were hydrolyzed and condensated in the acid solution. Then this precursor was reacted with the organic system-phase change material. In the part of in-situ, the inorganic system and the organic system were added in the bulk solution simultaneously. The TEOS administered the hydrolysis-condensation reaction to form a dense web construction on the paraffin droplets. The properties of the microcapsules prepared by the method mentioned previously were determined by TGA (Thermo gravimetric analyzer), DSC (Differential scanning calorimeter) and SEM (Scanning Electron Microscope). The results show that the paraffin microcapsules possess good encapsulation, its encapsulated yield could reach to 98% and its cracking temperature was from 250℃ raise up to 310℃. Moreover, the encapsulated rate of microcapsules was 66wt% after paraffin microcapsules suffered the high temperature 280℃ for 3 minutes.

並列關鍵字

sol-gel method ； tetraethylorthosilicate ； hydrocarbon ； precursor ； in-situ process

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以前置物法與同時聚合法包覆碳氫化合物之研究

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