本研究中主要使用對稱型嵌段共聚物聚苯乙烯-b-聚(甲基丙烯酸甲酯)(PS21k-b-PMMA21k，通過混摻未氘化聚苯乙烯(PS)與氘化聚苯乙烯(Deuterated Poly-styrene-d8, dPS)不同分子量的均聚物。利用光學顯微鏡(OM)、原子力顯微鏡(AFM)、掃描電子顯微鏡(SEM)等對真實空間的表面呈像，使用低掠角小角度X光散射儀(GISAXS)分析薄膜內部結構。
靜態GISAXS在230 ℃及270 ℃分別進行1 h與24 h的熱處理，以獲得奈米結構。透過量測一系列的入射角角度變化得到入射角解析(incident-angle-resolved, IAR) GISAXS圖與散射公式相互搭配，通過在out-of-plane擬合繞射點定性定量分析薄膜結構資訊如水平圓柱(Parallel Cylinder, C//)、穿孔層(Perforated layers, PL)與雙螺旋(Double Gyroids, G)，過程中使用繞射點映射(mapping)晶面，量化微域間距等方法，更深入的解析薄膜結構與GISAXS 2D 圖。
臨場(in-situ) GISAXS在210-280 ℃進行連續升溫，探討嵌段共聚物混摻的有序-有序(order-order transition, OOT)與有序-無序相轉變(order-disorder transition, ODT)，了解不同樣品相轉變發生範圍、結構變化、發生機制等，配合靜態GISAXS確認結構在降溫過程中是否發生改變。
最後靜態實驗結果顯示，230 ℃下結構已形成但有序性較差，270 ℃則需要更長時間達到平衡。臨場實驗中發現，混摻低分子量均聚物的樣品在升溫過程中可觀察到TODT，揭示低分子量均聚物會屏蔽介面交互作用使TODT降低。而高分子量均聚物混摻樣品顯示出對介穩態結構的穩定性，更長時間的存在。比較後觀察到，在未超過TODT的溫度下，結構在降溫過程中無明顯變化，表明可快速升溫至所需結構溫度。這項研究提供了BCP混摻結構形成的關鍵資訊，對高分子材料設計和製程具有重要意義。

In this study, we primarily use symmetric block copolymer polystyrene-b-poly(methyl methacrylate) (PS21k-b-PMMA21k) blended with polystyrene and deuterated polysty-rene (dPS) homopolymers of different molecular weights. The surface morphology was analyzed using optical microscopy (OM), atomic force microscopy (AFM), and scan-ning electron microscopy (SEM), while the internal structures of the thin films were analyzed by grazing-incidence small-angle X-ray scattering (GISAXS).
In static GISAXS, samples were annealed at temperatures of 230 and 270°C for 1 and 24 hours to obtain nanostructures. By measuring a series of incident angle variations, incident-angle-resolved (IAR) GISAXS patterns were obtained and combined with scattering formulas. Through out-of-plane fitting of diffraction points, structures such as parallel cylinders (C//), perforated layers (PL), and double gyroids (G) were re-vealed. This analysis enabled the mapping of diffraction points to Miller indices, quan-tification of microdomain spacing, and a deeper understanding of the thin film struc-ture and GISAXS 2D patterns.
In-situ GISAXS was performed with continuous heating from 210 to 280 °C to investi-gate order-order transitions (OOT) and order-disorder transitions (ODT) of blended block copolymers. The study aimed to understand the range, structural changes, and mechanisms of phase transitions in different samples. Static GISAXS was also used to confirm whether the structure changed during the cooling process.
The static GISAXS experiment results showed that structures formed at 230 °C but had poor ordering, while at 270 °C, longer times were required to reach equilibrium. In the in-situ GISAXS experiments, samples blended with low molecular weight homopoly-mers exhibited TODT during the heating process, with low molecular weight homopol-ymers screening interfacial interactions and resulting in a lower TODT. Samples with high molecular weight homopolymers displayed stable metastable structures that per-sisted for longer times. Comparatively, we observed that at temperatures below TODT, the structures did not change significantly during cooling, suggesting that rapid heating to the desired structural temperature is feasible. This study provides critical insights into the formation of BCP blended structures, offering significant implications for the design and processing of polymer materials.

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