聚乙二醇末端基對雙分子量聚乙二醇混摻物結晶行為的影響

Abstract

本研究主要是探討小分子量聚乙二醇(PEG)不同的末端基(1OH-1CH3、2OH、2CH3、2NH2)混摻大分子量聚乙二醇(PEO)之二元結晶系統的相容性、結晶行為、與形態學的影響。相容性的探討方面，我們以微分掃瞄卡計(DSC)測定PEO平衡熔點的下降程度，並計算相互作用參數值。結晶動力學方面，則以偏光顯微鏡(POM)來觀測PEO的球晶成長速率，計算出不同系統中PEO折疊鍊端表面自由能；PEO結晶後PEG的總體結晶速度也以DSC量測之。不同PEG末端基對摻合系統的影響同時也以傅利葉紅外線光譜儀(FTIR)分析之。

The effects of end groups (1OH-1CH3, 2OH, 2CH3, 2NH2) of Poly(ethylene glycol) (PEG) on miscibility, crystallization behavior, and morphology of binary crystalline blends of PEG/Poly(ethylene oxide) (PEO) were investigated. Miscibility and Flory interaction parameter χ12 in different blend systems were derived with differential scanning calorimetry (DSC) according to depression of equilibrium melting point. Crystal growth rate of PEO was analyzed with polarizing optical microscope (POM), which led to the calculation of folding chain surface free energy of PEO in different blend systems. Overall crystallization rate of PEG was also studied after the crystallization of PEO. Effects of end groups were also investigated with Fourier Transform infrared spectroscopy (FTIR).