本研究觀察melt-quenched sPS薄膜在結晶前的液-液相分離行為(包括動態結晶以及等溫結晶)，實驗上以OM搭配phase contrast鏡頭實際觀測相分離結構，藉由小角度光散射法拍攝Hv影像判斷結晶的時刻，Hv除了可以判斷球晶尺寸外，也可積分得散射不變量QHv以探討晶體的體積分率。以FTIR結合加熱裝置，搭配timebase軟體，形成一組time-resolved FTIR，探討等溫結晶、動態結晶之結晶行為，以及結晶前的微結構變化。

在10 oC/min升溫的動態結晶中，實驗顯示相分離往往都是在晶體生成後，對比增加了，才得以被觀察到，且當相對結晶度達90%時，晶體會由深色domain跨到鄰近的淺色domain內，降低對比，另外在晶體開始熔化時，相分離結構的對比又開始增加，使相連結構又再次出現，換句話說，melt-quenched薄膜升溫時有兩種機制同時存在，液-液相分離以及液-固結晶。此外，在等溫結晶實驗中，可觀測到結晶前的光強度皆以對數的形式增加，並且在110 oC的等溫結晶實驗中，可以藉由phase contrast鏡頭觀測到結晶前的相分離行為。本實驗也嘗試以未安裝檢光板的SALS來觀測相分離，但由於相分離對比太弱，因而無法觀測到相分離產生的ring structure。

在1 oC/min升溫的動態結晶中，亦可觀測到結晶前的相分離行為，有趣的是，在晶體消失後，相分離結構並不會馬上消失，可知單成份高分子sPS在結晶前確實會先形成類似SD型的相分離。

Liquid-liquid phase separation preceding the crystallization of melt-quenched syndiotactic polystyrene (sPS) film upon dynamic crystallization and isothermal crystallization was observed via OM with phase contrast lens. Hv images of SALS were used to detect cystallization. In addition to the scattering peak for determining the spherulitic size, the integrated scattering intensity, invariant QHv, was capable to probe the volume fraction of spherulites. The crystallization and conformational change of the sample during heating could also be monitored by time-resolved FTIR.

From dynamic crystallization with a heating rate of 10 oC/min, it was showed that the phase-separation contrast was too low to observe morphological features under OM until crystallization was took place. While the relative crystallinity was about 90 %, the growing crystals spread across the phase boundary, so the interconnected domains were hardly discernible. However, the phase-separation contrast increased again and interconnected domains appeared when crystals started to melt. In other words, there were two kinds of phase transition, i.e., liquid-liquid phase separation and liquid-solid crystallization. Besides, the logarithmic increase of Hv intensities could be observed in the induction period from isothermal crystallization. Our results showed that the interconnected domains preceding crystallization could be clearly seen from isothermal crystallization at 110 oC. We also tried to observe the phase separation by using SALS without analyzer. But, the phase contrast was too low to detect the phase-separated structure and no ring pattern was seen.

From dynamic crystallization with a heating rate of 1 oC/min, the interconnected domains preceding crystallization was also observable. Interestingly, the interconnected domains did not immediately disappear when all crystals were melted. In a nutshell, phase separation induced by SD in single component sPS really took place prior to the formation of stable nuclei.

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