請用此 Handle URI 來引用此文件:
http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/25395
標題: | 以相分離法製備微膠囊包覆精油 Preparation of Oil-containing Poly (vinyl alcohol) Microcapsules through Phase Separation |
作者: | Keng-Chao Wu 吳庚釗 |
指導教授: | 徐治平(Jyh-Ping Hsu) |
關鍵字: | 微膠囊,相分離法,聚乙烯醇, microcapsules,phase separation,poly(vinyl alchol), |
出版年 : | 2007 |
學位: | 碩士 |
摘要: | 本實驗使用聚乙烯醇Poly(vinyl alcohol) (PVA)為殼材,以香精油為核材,利用相分離原理,以簡單凝膠法,以戊二醛為交聯劑進行微膠囊包覆。討論攪拌速率、反應溫度、精油及乳化劑體積比率對所製備之微膠囊形態、粒徑分佈及包覆率的影響,並使用Design-expert 5,進行變因間交互影響分析。得知攪拌速率越高,得到粒徑越小,但造成精油揮發較多,易產生PVA聚集的粒子。反應溫度較高時,精油揮發較多,得到粒徑較小,但在精油量足夠時,由於溫度高,交聯反應較快,粒徑較大。精油量若過低,則容易形成PVA聚集,若提高精油量,乳化劑的量也需相對提高,以提供足夠的分散效果與保護。此時精油量越大所製備之微膠囊粒徑越大。由Design-expert 5軟體分析結果顯示,固定乳化劑,對微膠囊粒徑影響的因素重要性為:精油體積>攪拌速率>反應溫度,包覆率影響的因素重要性為:精油重量>反應溫度>攪拌速率。改以精油與乳化劑總體積為油相體積,進行分析,則對粒徑影響的因素重要性為:反應溫度>攪拌速率>油相體積,對包覆率影響的因素重要性為:油相體積>反應溫度,攪拌速率幾乎不影響。 Oil-containing poly (vinyl alcohol) (PVA) microcapsules were prepared by simple coacervation followed by the chemical cross-linking of coacervated PVA membrane with glutaric aldehyde through phase separation method. The effect of the process parameters such as agitation speed, temperature and the amount of oil and emulsifier on the capsule size distribution and capacity were investigated and Design-expert 5 was used to find out the interaction between process parameters. It was shown that high agitation rates resulted in a reduction of the size of microcapsules, but more oil evaporated and more PVA aggregation as the effect of higher temperature with less oil . On the contrary, with sufficient oil the higher temperature made the crosslinking rate and the size of microcapsules increase. If more oil is used, more emulsifier was needed to protect the oil droplets so that the capsules size increased. The analysis through Design-expert 5 shown that with constant emulsifier volume, the order of the influence on the capsules size distribution was oil volume ratio>agitation speed>temperature and oil volume ration>temperature>agitation on the capacity. Combining oil and emulsifier as oil phase volume, the order of the influence on the capsules size distribution was temperature>agitation speed>oil phase volume and oil volume ratio>temperature and agitation speed had no effect on the capacity. |
URI: | http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/25395 |
全文授權: | 未授權 |
顯示於系所單位: | 高分子科學與工程學研究所 |
文件中的檔案:
檔案 | 大小 | 格式 | |
---|---|---|---|
ntu-96-1.pdf 目前未授權公開取用 | 1.97 MB | Adobe PDF |
系統中的文件,除了特別指名其著作權條款之外,均受到著作權保護,並且保留所有的權利。