利用表面改質調控嵌段共聚物在奈米柱狀孔洞中微結構的方向性

Abstract

本實驗以BPO/TEMPO所形成之氮氧自由基的方式合成無規則共聚物P(S-r-BCB-r-4VP)，以此無規則共聚物熱交聯在陽極氧化鋁的奈米孔壁上，形成一層網狀交聯的奈米管，以達到孔洞改質的目的，探討嵌段式共聚物在改質後的奈米孔洞之微相分離的變化性。 以溶液潤濕法將P(S-r-BCB-r-4VP)溶液藉由毛細作用滲入陽極氧化鋁的奈米孔洞裡，待溶劑蒸發後，形成奈米管來達到孔洞改質的目的，再將嵌段式共聚物以熔融態灌入P(S-r-BCB-r-4VP)奈米管，形成外圍有一層P(S-r-BCB-r-4VP)之嵌段式共聚物奈米柱，發現在特定組成比例之無規則共聚物的孔洞改質下，可以改變嵌段式共聚物兩鏈段對於管壁的親好程度。在層狀系統，原本平行於孔壁的層狀結構將會轉變成垂直於孔壁的層狀結構，而在柱狀系統，原本平行於孔壁作排列的柱狀結構，經改質後也在形態上發現到與以往不同的螺旋狀結構。

A series of benzocyclobutene-functionalized random copolymers of styrene and 4-vinylpyridine were synthesized by nitroxide-mediated controlled radical polymerization. Our goal was to use these crosslinked random copolymers of P(S-r-BCB-r-4VP) as surface-modifiers to control the orientation of microdomains in lamella-forming and cylinder-forming of block copolymers in cylindrical nanopores of anodized aluminum oxide (AAO) membranes. We introduced P(S-r-BCB-r-4VP) into the cylindrical nanopores of the AAO to form nanotubes. The block copolymers were then drawn through capillary forces from melt into P(S-r-BCB-r-4VP) nanotubes and phase separated in a confined environment where air-film interfaces are eliminated. For the compositions of random copolymers which are neutral to PS and P4VP blocks, we observed the orientation of the lamellae will change from parallel to perpendicular to the walls. For the cylinder-forming block copolymers, the morphology has changed from simple cylinders oriented parallel to the nanopores to a morphology where the cylinders form helices within the nanopores after nanopores modification.