乳液安定性控制因素

Stabilization factors of oil-in-water emulsion

賴碧玉(Chris Lai)

指導教授 ： 余子隆

元智大學/工程學院/化學工程與材料科學學系/碩士(2002年)

摘要

乳液不安定的因素非常復雜,但歸究其原因可分兩個方向來討論, 一是從乳化過程中所考慮到的變因 : 攪拌速率 ' 操作溫度 ' 乳化劑的用量 ' 乳化劑種類的選擇及不同添加順序等 ; 二是乳液的立體障礙作用及儲存環境的因素
從實驗結果中說明了: (1)攪拌速度越高所提供的能量就越大,可使分散相液滴粒徑(particle size)更小, (2)乳化劑的親水基會因為溫度的提高使水合作用下降,並大大地減少其乳化效果,(3)界面膜強度與否決定了乳化劑的用量,濃度太低界面膜的強度不夠, 濃度太高反而使乳液不穩定, 因此最適量才能達到乳化效果 (4)混合乳化劑的結構與界面膜強度有關, 當界面活性劑分子吸附在界面膜上排列方式是緊密時,有利於乳液的安定,(5)對於O/W型乳液來說此時HLB值偏親水性且與水的溶解度高,所以是選擇將油相加入乳化劑-水相中,(6)配方中添加天然或合成的高分子聚合物這類增稠劑,可增加連續相的黏度以達到界面膜之間的立體障礙作用,藉此穩定乳液的安定性,(7)存放溫度過高易使液滴之間的互相碰撞機會提高,更增加乳液的不穩定度
因此,乳化的方式以及乳液配方的選擇,對於能否製作成乳液穩定狀態 是本報告的重點

關鍵字

乳液 ； 乳化 ； 乳化劑 ； 界面膜

並列摘要

The factors concerning the unstability of emulsion are very complex. Two of the most important factors are emulsification process and storage environment . In this report the effects of emulsification process including mixing speed, operation temperature, emulsifier concentration and emulsify type etc, on the stability of emulsion was discussed. The storage environment was controlled under 40C in oven.
The experiment results indicate that : (1) high mixing speed causes a reduction in particle size. (2) raising temperature reduces the extend of hydration of emulsifier. (3) the concentration of emulsifier depends on the stability of film surface. (4) close packing of surfactant molecular chains on surface film improves the emulsion stability. (5) addition of oil phase into emulsifier-water phase is a better process for making a for oil-in-water emulsion system. (6) addition of a polymer as thickener increase the viscosity of a continue phase which improve stabilization of emulsion. (7) collision among oil droplets would cause unstability of oil-in-water emulsion when temperature is above 40C.

並列關鍵字

emulsion ； emulsification ； emulsifier ； surface film

參考文獻

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Clayton W., The theory of emulsion and their technical treatment . 4th ed., The Biskiston Co., New York ,1943.

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