本研究為探討二苯亞甲基山梨醇(DBS)奈米纖維形成與聚乳酸(PLA)結晶成長之間的關係。利用溶液鑄膜法將DBS均勻分散於PLA中，添加不同的DBS含量與選用不同的結晶溫度，來進一步觀察PLA球晶成長之變化。我們發現在結晶溫度大於120℃且DBS含量大於3 wt％時，會在偏光顯微鏡(POM)的觀測下出現罕見的同心圓結構。因此我們進一步利用掃描式電子顯微鏡(SEM)來觀察球晶成長與纖維形成的時間關係，推得了一系列變化的時間軸，再經由核磁共振光譜儀(NMR)確認DBS的添加確實改變了PLA結晶的形態與雙折射性質。而在微差掃瞄熱卡計(DSC) 與X射線繞射儀(XRD)的分析中，我們發現DBS的添加影響了PLA結晶的臨界溫度，使PLA結晶更容易趨向規則性較高的α型態。 This research focus on the interaction between DBS nanofibrils formation and PLA crystallization. We use solution casting process to mix DBS and PLA, adding different quantity of DBS and using different crystallization temperature to observe the change of PLA. The observation of morphology by POM shows that when DBS content is over 3 wt% and crystallization temperature is higher than 120℃, a concentric circles structure will appear. Therefore, we make a further observation of SEM to find out the timeline of PLA spherulite growth and DBS nanofibrils formation. With the results of NMR spectrum, we can confirm that the addition of DBS truly changed the morphology and birefringence of PLA crystal. From the analysis of DSC and WAXD patterns, we found that the addition of DBS affect the critical temperature of the crystallization of PLA, and leading PLA crystallization to a higher order α form.
