本實驗利用Two-step溶液聚合法自行合成可供TEM型態研究之非極性式PU，其軟質段(soft segment)為HTpolyIP (Hydroxyl-terminated Polyisoprene)，硬質段(hard segment)則由二異氰酸鹽MDI(4,4`-diphenylmethane diisocyanate)與鏈延長劑(chain extender)BD( 1,4-butanediol )所構成。 過去本實驗室針對第二吸熱熔融峰(T2：long range order)上之研究，認為T2結構可能是屬於不完整的晶形(paracrystalline介穩晶態)，所以T2結構能夠經由長時間的回火逐漸轉變成T3微結晶結構。因此本實驗提出以相分離程度較完全之非極性PU為材料，以及過去實驗室發現由MDI-BD及Poly-IP，且硬質段含量為55%所合成出的非極性PU，發現其型態為長圓柱狀(cylinder)或是平板狀(lamellar)，而因為極為規則度，所以本實驗提出以此系列的樣品透過動態回火與靜態回火處理程序，透過TEM來觀察硬質相中在不同規則度下的排列變化情形，並找出各種規則度下PU結構與型態的關係。 另外，這些PU樣品可從FTIR證明其相分離(phase separation)程度很高，因此可以消除軟硬質相互溶所衍生的變數。而以DSC、TEM、WAXD等儀器嚴謹且有系統地探討經由動態與靜態回火之後，PU硬質相第二熔融峰(T2：long range order)與第三熔融峰(T3：microcrystalline)微結晶等性質關係。在硬質相第二熔融峰行為方面，從等溫回火、升溫掃描的研究結果發現，隨著回火溫度的提升，T2熔融峰會往高溫偏移，且最後併入T3熔融吸熱峰中。期許本研究能夠給予PU在型態、結構與性質上的關係，提供更進一步的解釋方向。 The experiment employed two step solution polymerization to synthesize nonpolar-based segment polyurethane offered to the study of morphology. Its chemical formula of soft segment is poly-IP (hydroxyl-terminated polyisoprene), and the hard segment is composed of MDI (4, 4´-diphenylmethane diisocyanate) and BD (1, 4-butadiol). Our previous research on T2 (long range order) had found that it transformed the structure gradually into T3 (microcrystalline) structure through long-time annealing; therefore we came out with a conclusion that its structure is probably paracrystalline. The experiment utilized better-performed phase-separated nonpolar-based PU, synthesized by MDI- BD, Poly-IP and hard segment content 55%, direct observation the morphology by TEM, discover its shape was a long cylinder or lamellar form, which it’s in a regular state. With this in mind, we proposed dynamic annealing and static annealing to observe the regularity of hard segment, searching for the connections between structures and morphology under different regularity thus. FTIR shows that the phase separation of these PU samples is to a great extent, so as to eliminate the variables of reciprocal dissolution of hard and soft segment. Furthermore, we combined the result of TEM with the results of DSC, WAXD, etc. We could determine how the properties between T2 and T3 by means of dynamic annealing and static annealing. With what we had obtained; we do expect to bring PU into further prospect.
