對排聚苯乙烯 (sPS)非晶相膜在不同熱處理下，利用偏光顯微鏡(POM)搭配phase contrast鏡頭，觀察晶體形態變化。為了消除薄膜的熱歷史，在275到300 oC之間選取數個溫度 (Tmax)來熔化樣品。

試片的熱處理程序為由室溫升溫到不同Tmax，於Tmax下等溫不同時間後，冷卻至結晶溫度 (Tc)，於Tc下等溫結晶。由實驗中可發現當試片由室溫升溫到Tmax時會發生冷結晶，在134 oC可發現晶體和相連結構 (interconnected structure)，隨著樣品的熔化，晶體和相連結構會逐漸縮小，然而這些結構在熔融結晶過程時又會再重新出現

於冷結晶過程中，可觀察到類似於SD型相分離的相連結構。當Tmax為275 oC熔化的試片，熔融結晶時可得到與上述冷結晶相似的結構，此晶體很小且結晶形態呈現α晶型的特性。對於在Tmax高於280 oC時熔化的試片，在初始結晶時無法觀察到相連結構，但會有零星的晶體存在，晶體長滿後可觀察到較大的球晶及相連結構。由結晶時的穿透光強度變化圖可知，當結晶溫度介於280與285 oC時將可觀察到。

Syndiotactic polystyrene (sPS) in the amorphous form films were used to observe the morphological transition under heat treatments. The morphology was observed using phase contrast and cross polarized microscope. Several maximum temperatures (Tmax) ranging from 275 to 300oC were used to melt the samples.
Heat treatment sequences applied to samples include heating from room temperature to Tmax, annealing at Tmax, cooling from Tmax to crystallization temperature (Tc) and annealing at Tc. Cold crystallization of samples occurred while heating samples from room temperature to Tmax. Crystals and interconnected structures started to appear at 134oC. Crystals and interconnected structures diminished when samples melted. They reappeared after melt crystallization process took place.
During cold crystallization process, interconnected structure, which is similar with SD-type phase separation structure. Similar structure also obtained during melt crystallization process for samples melted previously at 275oC. Crystals obtained by cooling from this Tmax were tiny and showed the characteristic of α-form sPS. For sample melted at Tmax higher that 280oC, in the beginning of crystallization time, no interconnected structure was observed but crystals were formed sporadically throughout the sample. In the end of crystallization process, larger spherulites and interconnected structure were obtained for those samples. From light intensity profile during crystallization, profile transition occurred between Tmax of 280 and 285oC.

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