- 學位論文
檸檬酸添加劑於溶液法製備澱粉/聚丙稀酸膜之改質
The effect of citric acid on starch/PAA blend films using the solution-blend method
摘要
澱粉/共聚物之溶液共混於多元醇添加劑下，具備良好的性能並常用於材料開發與應用。本篇論文使用一系列的熱分析儀器在共混複合材料的研究，其中包括了動態及非動態性熱分析及其它基本分析項目。 研究主要針對澱粉/聚丙烯酸/檸檬酸共混物成膜後的性質分析；改質過程中不使用醇類塑化劑及共混程序的實驗設計。為得到特殊的澱粉改質作用而使用額外量的檸檬酸，並且使用5組不同比例量的澱粉/聚丙烯酸/檸檬酸共混物於適當溫度(70℃)下，以溶液混合法與糊化後的澱粉摻混。 由傅立葉轉換紅外光譜(FT-IR)指出在摻混及乾燥過程中有部分酯化反應的發生。對於熱重分析(TGA)的結果，具有檸檬酸存在時的熱穩定性提升及熱重損失減小，更加確信檸檬酸的添加能增強共聚物分子間作用力。萬能拉力機(BOSE)及楊氏模數測量表示，當有足量的檸檬酸加入聚丙烯酸/澱粉共混改質時，其延展性大幅提高。再由動態機械分析(DMA)測得儲存模數變化與檸檬酸/聚丙烯酸含量比有關。另一方面，玻璃轉移溫度於熱機械分析(TMA)及微分熱差分析(DSC)中吾人可知，檸檬酸能有效達到塑化作用及交聯度提升，但兩者是相互抵制的效應。再者，水滴於改質澱粉膜上的接觸角測試，將數據與聚丙烯酸及檸檬酸含量關係繪製成密度圖來呈現抗水性效果分佈；所有改質後的優勢可歸於檸檬酸及聚丙烯酸添加於聚醣分子結構中而產生交互作用。
並列摘要
Solution blending of starch/polymer with some polyol have good performance to be used in development and application of materials. In this work the behavior of blended compound is not only investigated by a range of thermal analysis instrumentation including dynamic or non-dynamic, but also the other terms of the analysis would be considered. This study concerns are the properties of the blend films of starch/PAA/citric acid copolymers without any glycerol influence and the elaborately process for preparing samples.The extra citric acid(CA) content was used for a special effect on starch films. A range of ratios of blended film of starch/polyacrylic acid(PAA) containing citric acid has been prepared at moderate temperature(70℃) from gelatinised starch by treatment in the solution-blending method. Results from Fourier Transform Infrared(FTIR) show that partial esterification occurred during the blending and drying process. As shown from thermogravimetric analysis(TGA), the excellence of thermal stability and weight loss decreased in the presence of the CA confirms that intermolecular force in copolymers was enhanced with the addition of the CA. BOSE ElectroForce and Young’s modulus test revealed the perfectly ductility capacity when the adequate quantity of the CA blended with PAA/starch. Storage modulus varies depending on addition of the CA and PAA ,that detected by Dynamic Mechanical Analysis(DMA). On the other hand, a interesting results can be seen at the glass transition temperature(Tg) by thermomechanical analysis(TMA) and Differential scanning calorimetry(DSC).Efficient plasticization and sufficient crosslinking are desired by using the CA, but they are frequently competitive event.Moreover, the contact angle of water on the film are plotted against the concentration of PAA and CA with density-figure to show improvement in water resistance properties. These advantages could be attributed to the good interaction between CA and PAA filler in the polysaccharide matrix.