具備快速成膜性與自修復能力之可調控式超分子網絡材料

Abstract

本研究利用氫鍵作用力作為超分子的非共價鍵作用力，將兩個分子量低於一千之寡聚物進行改質，以自然界的含氮鹼基互補對做為修飾官能基，導入後進行混摻，製備出具有高分子特性的薄膜。藉由氫鍵作用力所形成的物理交聯，此材料呈現的是一種非晶相(amorphous)的本質，具備快速成膜性與良好的機械性質，且可依不同的混摻比例來進行調控(依據不同混摻的薄膜，楊式模量36.8MPa~16.9MPa，延展性則從10%至最高600%)。此外，從變溫流變的結果探討中，我們證實了物理交聯的存在，材料從升溫實驗中展現了穩定的”鍵結破壞/再鍵結”的網絡系統，致使我們的材料能以簡單的加熱重製損壞或形變後的材料，並具有極佳的自修復能力。最後，與一般常見的高分子自修復薄膜相比，我們的材料藉由這種動態的超分子作用力，可以達到更好的修復效率(回復率高達92%)且材料呈現均相的微結構而無任何相分離的狀況，由以上結果，可以證明我們設計的新一代超分子混摻材料所具備之發展潛力。

In this thesis, we successfully introduced complementary nitrogenous bases into two different kind of low molecular weight oligomer, which exhibit amorphous nature, rapid film-forming and mechanical properties (Young's modulus= 36.8MPa ~ 16.9MPa, elongation= 10~600%, depends on different blending ratio) in solid state owing to the formation of complementary pairs by induced physical cross-linking. Surprisingly, Temperature dependent rheology data demonstrated the physical cross-linking of our material and confirmed the extremely stable reversibility for the re-bonding/dissociation of the network system and enabled the tuning of the mechanical properties using controlled blending of various ratios as powerful method to adapt and optimize the material system to specific requirements. In addition, compare with common polymer films used in self-healing ability and re-processing processing, our material can be effectively used as a dynamic crosslinker for the design of self-healing suparmoleuclar films, which show excellent self-healing capability(recovery rate could reach to 92%) without any phase separation occurred. Thus, this newly developed material provides a potential route toward design and fabrication of next-generation supramolecular polymers.