嵌段共聚物(Block copolymers)的自組裝特性可實現數十至數百奈米範圍內各種多樣形態的能力，而引起了極大的關注。其中調控薄膜中自組裝奈米微結構(nanodomain)的尺寸大小對於未來應用至關重要。在本研究中，嵌段共聚物溶解在選擇性溶劑中，形成具有核-殼結構的球形微胞，其中不溶性之嵌段傾向於形成核，而可溶性嵌段則優先形成殼。薄膜透過旋轉塗佈法(spin coating)製備而成。然後，將樣品在選擇性溶劑(丙酮)或中性溶劑(氯仿)的蒸氣中進行退火，使其從微胞至垂直取向的奈米微結構之結構演變。透過原子力顯微鏡(AFM)、掃描式電子顯微鏡(SEM)及低掠角小角度X光散射儀(GISAXS)對以不同溶劑蒸氣進行退火的聚苯乙烯-聚(2-乙烯基吡啶)(polystyrene-block-poly(2-vinyl pyridine), PS-b-P2VP)二嵌段共聚物的二元摻合物之自組裝特性和結構演變進行研究。結果證實，摻合兩種具有不同聚合度的嵌段共聚物可以控制薄膜中奈米微結構的大小。尤其在域間間距(inter-domain spacing)對於不同的溶劑種類觀察到相應的變化，且與暴露於不同的溶劑蒸氣下的二元混合物的薄膜之混合比例也有相異的依存性。這種方法容易使奈米微結構具有尺寸可調性以及形態多樣性。;Self-assembled of block copolymers (BCPs) have aroused great attention due to their ability to achieve diverse morphologies in the range of tens to hundreds of nanometer. Tailoring the dimension of self-assembled nanodomains in a thin film is essential for future applications. In this study, block copolymers were dissolved in a selective solvent, to form spherical micelles with a core-shell structure, in which the insoluble block formed the cores whereas the soluble block preferentially formed the shell. Thin micellar films were prepared by spin-coating. Then the as-spun specimens were annealed in a vapor of a selective (acetone) or neutral (chloroform) solvent to bring about the structural evolution from micelles to perpendicularly-oriented nanodomains. The self-assembly and structural evolution of binary blends of polystyrene-block-poly(2-vinyl pyridine) (PS-b-P2VP) diblock copolymers with various solvents were studied by atomic force microscopy (AFM), scanning electron microscopy (SEM), and grazing incident small-angle X-ray scattering (GISAXS). The results demonstrated that blending two block copolymers with different degrees of polymerization could control the domain size. In particular, the inter-domain distance varied in response to different solvent quality and behaved with different dependence of the blend ratios in thin films of binary mixtures under different solvent vapor. This approach easily allows nanodomains with size-tunability and morphological diversity.
