多重性氫鍵作用力之超分子組裝與應用

Abstract

本論文以開發具高識別性的氫鍵超分子官能基，接支在不同之高分子主體(多面體矽氧烷寡聚物、聚醯亞胺聚合物、聚環氧乙烷、聚環氧丙烷)的超分子材料，並針對其特定混摻系統進一步探討，為研究主體，內容分為四大主題: 1.多面體聚矽氧烷與聚醯亞胺聚合物各嵌入超分子官能基: 利用接合反應製備了接上分子識別能力官能基的多面體矽氧烷(MD-POSS)，並另以開環聚合高分子自組裝的技術，製備末端Uracil(尿嘧啶)官能基的聚胜肽的材料(U-PBLG)，探討MD-POSS與U-PBLG混摻後，在氫鍵作用力下探討其特性變化。利用 FTIR(紅外吸收光譜) 及1 H NMR(核磁共振儀)光譜來觀察MD-POSS 和 U-PBLG 之間特殊的多重氫鍵作用力，並計算出在d-chloroform溶劑中的結合常數為 114 M -1。以及利用液相圓二色分光光譜儀，證實了分子間強烈氫鍵作用力的存在。廣角X光粉末繞射圖中，U-PBLG在混摻入MD-POSS後於固態下出現了較明顯的的布拉格特徵峰，顯示經過混摻後於氫鍵作用力下，促使結構出現結晶的有序排列。最後，由DSC與TEM圖中，在U-PBLG成分較少的混摻比例情況下，氫鍵作用力效應促使系統呈現均相；U-PBLG增加的比例下，因結構差異性效應提昇造成相分離，更觀察到特殊的二級平板(secondary lamella)聚集的形貌。 2.多面體聚矽氧烷與聚環氧乙烷各嵌入超分子官能基: 利用接合反應製備了接上分子識別能力官能基的多面體矽氧烷(MD-POSS)，並利用Michael addition製備單末端與雙末端含Uracil(尿嘧啶)官能基的聚環氧乙烷材料(U-PEG與U-PEG-U)，經由不一樣比例的混摻，利用電子顯微鏡與動態光散射儀探討超分子自組裝結構，且利用FTIR及NMR佐證多重性氫鍵分子間作用力的存在。 3.含尿嘧啶聚環氧乙烷之寡聚物材料與鋰鹽LiASF6混摻: 利用單末端與雙末端含Uracil(尿嘧啶)官能基的聚環氧乙烷材料(U-PEG與U-PEG-U)跟鋰鹽LiASF6進行部一樣比例的混摻。從交流阻抗儀可以得知各成分比例對於整體導電度的變化，以U-PEG為主體的混摻系統其導電度比對照組還高，因此利用差熱分析(DSC), WAXS(廣角X光散色儀),7Li NMR(鋰譜核磁共振儀)與FT-IR(紅外吸收光譜)去探討尿嘧啶在鋰離子傳導上的貢獻。 4.含特殊強氫鍵作用力官能基之聚環氧丙烷與多層石墨混摻: 合成出含尿素-尿嘧啶雙邊之聚環氧丙烷(Ur-Cy)2PPG，與對照組含尿嘧啶雙邊之聚環氧丙烷(Cy)2PPG，以差熱分析(DSC)，NMR(核磁共振儀)， FT-IR(紅外吸收光譜)，WAXS(廣角X光散色儀)，SAXS(小角X光散色儀)與 Rheology(流變儀)探討氫鍵強弱對於物質基本性質的變化原因，並且利用TEM (穿透式電子顯微鏡)與SEM (場發式掃描電子顯微鏡)得知其內部結構的自組裝變化。在與石墨混摻之後，利用Raman spectra(拉曼光譜), XPS(化學分析電子能譜儀), TEM(穿透式電子顯微鏡), and AFM(原子力顯微鏡)觀察出石墨經由超強超分子作用力之聚環氧丙烷(Ur-Cy)2PPG混摻後，其石墨狀態變為少層的石墨稀狀態。

In this study, we focus on four major subjects which based on different backbone (Polysilsesquioxane, Poly-Benzyl L-Glutamate, Poly(ethylene glycol) and Poly(propylene glycol)) of supramolecular materials for understanding the properties changes: 1.Block-copolymer-like supramolecules confined in nanolamellae This paper describes the development of a new concept in supramolecular assembly of existing functional polypeptides to form diblock-like molecular clusters through complementary hydrogenbonding interactions, providing a potential route toward design and fabrication of block copolymer-like supramolecular materials. 2.Supramolecular structures of uracil-functionalized PEG with multi-diamidopyridine POSS through complementary hydrogen bonding interactions In this study, we synthesized (i) a multi-diamidopyridine-functionalized polyhedral oligomeric silsesquioxane (MD-POSS) through nucleophilic substitution and click 1,3-cycloaddition reactions and (ii) both mono- and bis-uracil (U)-functionalized poly(ethylene glycol) derivatives (U–PEG and U–PEG–U, respectively) through Michael additions of U to acryloyl-functionalized PEG oligomers. Transmission electron microscopy (TEM) and dynamic light scattering (DLS) revealed that supramolecular structures self-assembled from mixtures of MD-POSS and U–PEG and from MD-POSS and U–PEG–U. Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopy confirmed the presence of multiple hydrogen bonding interactions between the diaminopyridine groups of MD-POSS and the U groups of U–PEG and U–PEG–U. Because of these strong reversible intermolecular multiple hydrogen bonds, the POSS-based polymer-like supramolecular materials exhibited improved thermal properties upon increasing the MD-POSS content. 3.Supramolecular Functionalities Influence the Thermal Properties, Interactions and Conductivity Behavior of Poly(ethylene glycol)/LiAsF6 Blends In this study, we tethered terminal uracil groups onto short-chain poly(ethylene glycol) (PEG) to form the polymers, uracil (U)-PEG and U-PEG-U. Through AC impedance measurements, we found that the conductivities of these polymers increased upon increasing the content of the lithium salt, LiAsF6, until the Li-to-PEG ratio reached 1:4, with the conductivities of the LiAsF6/U-PEG blends being greater than those of the LiAsF6/U-PEG-U blends. The ionic conductivity of the LiAsF6/U-PEG system reached as high as 7.81 × 10−4 S/cm at 30 °C. Differential scanning calorimetry, wide-angle X-ray scattering, 7Li nuclear magnetic resonance spectroscopy and Fourier transform infrared spectroscopy revealed that the presence of the uracil groups in the solid state electrolytes had a critical role in tuning the glass transition temperatures and facilitating the transfer of Li+ ions. 4.Properties Change of New Suprapolymer with Ureido-Substituted Cytosine Groups Tethered on Low Molecular Weight Poly (propylene glycol) and Exfoliation from Graphite to Few Layer Graphene in Graphite/Suprapolymer blends Suprapolymer (Ur-Cy)2PPG which has strong complimentary supramolecular recongnition between urea-cytosine functional group was successfully synthesized. The reversible properties after breaking H-bond by heating and shearing can be proved by temperature-dependant NMR, FT-IR, WAXS, SAXS and strain-dependant rheology. From DOSY measurement, the repeat unit of (Ur-Cy)2PPG would be about 2500. (Ur-Cy)2PPG makes the self-associational crystalline property to button up the building block in lamella structure compared with (Cy)2PPG which has an amorphous property. The exited result of exfoliation from graphite to few layer graphene by simple blending with suprapolymer (Ur-Cy)2PPG and ultra-sonication process and can be expected to have the insertional interaction between pi orbital by graphite and urea-cytosine groups, improved by Raman spectra, XPS, TEM, and AFM images.