新穎非對稱型偶氮苯之光響應超分子複合材料

Abstract

本篇論文是在研究利用互補氫鍵列陣的分子識別方式，使具有生物可相容性的接枝含氮鹼基聚酯材料與DAP之染色分子形成非共價鍵結的網狀結構。我們以開環聚合和點及化學的方式合成出一系列不同組成的poly(εCL-g-Uracil)，並且從WAXD、OM和DSC等方式發現聚酯材料在接枝多點式氫鍵的Uracil後，PCL的結晶性被破壞。我們更將本研究所合成的仿生接枝聚酯纖維材料送到食品工業研究所進行體外細胞毒性測試，送測結果顯示我們的材料並不具有細胞毒性，適合應用在生醫材料領域來進行研究或使用。此種類似於RNA形式的高分子-偶氮苯混摻系統的超分子相關的結構以及多點式氫鍵作用力有詳細的研究以及探討。這種”高分子-偶氮苯”複合材料可藉由光和熱的驅動而有不同的結構轉變，並且伴隨著材料熱性質的改變。此外由AFM的表面形貌量測以及接觸角的水滴測量有顯著的光響應變化，DLS更證明了我們的混摻系統具有光控制聚集的現象。

Nucleobase-grafted biocompatible polyester was transformed into non-covalent network film through biocomplementary hydrogen bonding recognition in the presence of diamidopyridine-based dye molecules (DAP). A series of biomimetic copolymers, poly(εCL-g-Uracil)were synthesized through combination of sequential ring-opening and click chemistry. Wide-angle X-ray diffraction, OM and Differential scanning calorimetry indicate that Grafting this multiple hydrogen bonding motif onto poly(ε-caprolactone) dramatically destroy the crystalline as a result of formation of supramolecular polymer. The Biomimetic graft polyesters prepared in this study are shown to be biocompatible by in vitro cytotoxicity, suggesting their suitability for biomaterial applications. Specific interactions between polymer-azobenzene supramolecular structures of RNA-like diblock copolymer and their molecular recognition mediated by hydrogen bonding interactions were investigated in detail. The polymer-azobenzene complexes can be used to alter material behavior with light, switching both optical and thermal properties. The AFM micrograph shows Remarkable changes in the surface morphology and the contact angle with water were also observed. In addition, dynamic light scattering analyses provided evidence for “light-controlled aggregation” in these blend systems.