此研究主要是在不同晶相成長溫度，探討膜厚改變以及添加成核劑，對於高分子低維度晶相成長之影響。所研究的系統分別為膜厚13 nm和27 nm的聚左乳酸分子Poly-(L-lactic acid) (PLLA)薄膜，以及利用矽氧烷寡聚物OctaIsobutyl polyhedral oligomeric silsesquioxanes (IPOSS)作為成核劑，與聚左乳酸分子(PLLA)混摻比製作成膜厚13 nm之薄膜。13 nm薄膜厚度，約相當於單層的板晶厚度，因此有利於觀察低維度的結晶成長。另外也就探討四氫呋喃Tetrahydrofuran (THF)溶劑蒸氣對於聚左乳酸分子(PLLA)晶相成長以及再結晶行為之影響。
透過電子顯微鏡的觀察，發現膜厚增加對於聚左乳酸分子(PLLA)晶相成長行為有顯著的影響，不止晶相成長速度大幅提升，結晶形態也發生變化。原本在低溫(80 °C)晶相成長所生成的edge-on板晶，具有朝順時針彎曲的趨勢存在，形成S形曲線(S-curve)。但當膜厚增加(27 nm)時，edge-on板晶分支在結晶初期就出現，且與膜薄時不同，板晶分支是從同ㄧ個點向外，順時針與逆時針彎曲同時發生的對稱成長。
此外，透過矽氧烷寡聚物(IPOSS)的混摻，也可改變聚左乳酸分子(PLLA)的晶相成長行為。利用偏光顯微鏡做in-situ觀察發現，混摻IPOSS的聚左乳酸(PLLA)薄膜，在等速降溫的過程中，結晶成長開始發生的溫度明顯提高。但當混摻薄膜厚度降至13 nm時，透過電子顯微鏡的觀察指出，薄膜內的結晶成長速率大幅下降。且在低溫(80 °C)結晶成長時，edge-on板晶分支(lamellar branching)現象也較不容易產生。而在高溫(120 °C)結晶成長所生成的flat-on板晶，在混摻過後也變得粗大且不規則，連原本不易生成的edge-on板晶也伴隨著大量出現。因此可知，當薄膜厚度減少，矽氧烷寡聚物(IPOSS)於聚左乳酸分子(PLLA)中雖然可以扮演成核劑的角色，增加edge-on板晶的成長，但在另一方面，卻抑制了分子鏈段的擴散與晶相的成長速率。
除上述透過膜厚及混摻成核劑，來改變聚左乳酸分子(PLLA)低維度的晶相成長外，也嘗試利用溶劑蒸氣來誘發薄膜晶相成長及再結晶。將未經持溫的13 nm聚左乳酸分子(PLLA)薄膜，直接置放於四氫呋喃(THF)溶劑蒸氣中。由電子顯微鏡觀察可發現，溶劑蒸氣可以很快的誘發晶相成長，原本在不同晶相成長溫度所形成的flat-on板晶和edge-on板晶可以同時在室溫成長。且所生成edge-on板晶朝逆時針彎曲成長，與直接在晶相成長溫度持溫形成的結晶剛好相反。另外也分別將已經在高溫及低溫晶相成長溫度結晶完的薄膜，置於四氫呋喃 (THF)溶劑蒸氣中數小時，發現隨著置放的時間增加，原本的結晶會先溶解，然後發生再結晶的現象。

This research was intended to improve the mechanical properties and degradation rate of PLLA by changing film thickness and mixing in POSS as the nucleating agent. The chemical formula of PLLA is (C3H4O2)n and that of POSS is (RSiO1.5)n.
The experiment result suggested that the increase of film thickness contributes greatly to the growth rate of crystals, whereas the addition of POSS particles did the completely the opposite. The lamellar morphology also had been changing, when the film thickness increased and POSS-mixed. The branching of edge-on lamella were somewhat symmetric as the film thickness increased. And the POSS particles preferentially induced the growth of edge-on lamellae at a higher selected temperature of 120 °C; both the edge-on lamella and flat-on lamella were observed.

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