- 學位論文
利用恆溫滴定卡計對高分子溶液之溶劑性質之研究
Solvent Quality of Polymer Solution: Isothermal Titration Calorimeter (ITC)
摘要
高分子溶液性質的研究，是高分子科學領域的重要內容之一，而由Flory及Huggins 所提出的相互作用參數(interaction parameter,χ)，則是用以了解高分子溶液性質的重要指標，可以有效幫助我們了解高分子溶液內，分子間的相互作用，不過一般最常用以估算χ值的方法，乃是藉由溶解參數(solubility parameter ,δ)計算而得；而本文則是採實驗方法，利用恆溫滴定卡計(Isothermal Titration Calorimeter , ITC )直接測量溶液混合或稀釋所產生的微小熱量，再換算成χ；並輔以滲透壓凝固點下降法加以佐證。 本文主要探討數種不同中性高分子於水溶液中之χ，以及高分子之分子量與其濃度對於χ的影響。由實驗結果發現：χ受濃度影響不大，而分子量的影響效應則較為顯著，且χ隨分子量上升而上升。此外我們也發現，由溶解參數(δ)計算得到之χ必為正值；但利用ITC針對水溶性較好的高分子，直接測得其水溶液之χ，則其值皆小於零。
並列摘要
Solvent quality of polymer solution is an important quality of polymer science, and it affects the thermodynamic parameter of polymer solution. However, in the context of a binary mixture of polymer and solvent, “the interaction parameter (χ)”represents the solvent quality. In this thesis, the “Isothermal Titration Calorimeter (ITC)” is applied to measure the χ parameter of polymer solution. It is found that “the interaction parameter (χ)”of PEG、PVP、Dextran aqueous solution are negative and they are increased with increasing molecular weight of polymer solution. In addition to molecular weight effect, we has study the concentration effect. For PEG aqueous solution, χ parameter of different concentration is nearly constant. For PVP aqueous solution, in low concentration region, χ parameter is increased with increasing concentration of polymer solution. But in high concentration region, χ parameter is nearly constant.