頁籤選單縮合
題 名 | 超臨界流體製備氣凝膠之研究=Aerogels Formation and Drying with the Aid of Supercritical Fluid |
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作 者 | 張育誠; 吳國光; 焦鴻文; | 書刊名 | 石油季刊 |
卷 期 | 48:2 2012.06[民101.06] |
頁 次 | 頁17-26 |
分類號 | 460.04 |
關鍵詞 | 溶膠凝膠法; 氣凝膠; 超臨界流體; 乾燥; Sol-gel method; Aerogel; Supercritical fluid; Drying; |
語 文 | 中文(Chinese) |
中文摘要 | 一般為獲得高性能之氣凝膠,多數於乾燥過程中採用超臨界流體乾燥方式,將藉由流體於超臨界狀態下,可比一般液體的滲透能力更佳,並呈現親有機性有效溶解有機溶劑,進而製備出多孔、低密度、低熱傳導係數之氣凝膠。本研究中將可能影響氣凝膠以超臨界乾燥製程之因素,予以歸納,大致可分為乾燥條件、膠體置放方式、膠體原料性質及超臨界流體種類等四項因素。藉由所歸納之四項因素,進行實驗設計與製程控制,提升乾燥效果。本研究結果顯示,以二氧化碳超臨界乾燥方式,進行二氧化矽氣凝膠與二氧化矽-二氧化鈦氣凝膠之乾燥製備,其材料孔隙率可達90~95 %、密度為0.1~0.12 g/立方公分,且熱傳導係數可達到0.04 W/m-K。 |
英文摘要 | Currently aerogel, one of the advanced light thermal insulated materials, is capable with high specific surface area, high pore ratio, low density and low thermal conductivity. Monolithic silica aerogels can then only be produced when the ethanol is removed in the absence of capillary forces in the gel pores, because even small capillary forces will result in a collapse of the gel skeleton and will crack the gels. Supercritical drying techniques must be applied to exchange the pore liquid with air while maintaining the solid network. In this study, aerogel were prepared through sol-gel processing with supercritical drying method. |
本系統中英文摘要資訊取自各篇刊載內容。