| 摘要: | 結晶工程已發展出以自組裝現有分子產生新型固體而不需破壞或形成共價鍵的方法。以共晶化合物來量身訂做材料特性，已激發許多研究人員在結晶工程領域的興趣。 冠醚是超分子化學的代表之一。不僅是廣泛用在超分子化學和結晶工程中作為不同類型陽離子如水合氫離子(H3O+)、銨離子(NH_4^+)的主體而且也能藉由形成氫鍵和鹼金屬/過渡金屬離子和氫化陽離子形成穩定的錯合物。不同的冠醚有不同的分子孔洞大小且大部分可和特定陽離子有緊密鍵結。本論文中，硝酸銨被選用希望能改變其晶貌並希望誘導出新的具有特殊物理化學性質的同質異構物。 首先，利用23種有機溶劑篩選的方式，有關構形IV 硝酸銨的溶解度(solubility)、多形性(polymorphism)、結晶度(crystallinity)、晶貌(crystal habit)以及多晶形表(Form Space)的資料被完整收集。其次，基於硝酸銨和冠醚的多晶形表，利用反溶劑法可生成一新的1:1硝酸銨—苯并18冠6醚共晶化合物。分析工具，如LTDSC, TGA, FT-IR, OM, PXRD, SXD被用來了解其超分子結構和確定其分子間的化學劑量比。同時，也進行1:1硝酸銨—苯并18冠6醚共晶化合物的球型結晶研究。最後進行此共晶化合物的燃燒速率、溶解度和溶解速率的測量以便了解其性質。 Crystal engineering had developed a manner that it applied self-assembly of existing molecules to generate a new solid without the need to break or form covalent bonds. Cocrystals have excited the interest of many researchers in the crystal engineering field as a way to tailor-make material properties. Crown ethers are one of the symbols of supermolecular chemistry. This is not only because of their extensive utilization in supermolecular chemistry and crystal engineering as hosts for variety of cationic species such as hydronium ion (H3O+), ammonium ion (NH_4^+) but also because crown ethers are able to form stable complexes with alkali or transition-metal ions and hydrogenate cations via hydrogen bonding. The different crown ethers have different cavity szies and can be chosen to bind most strongly with a given cation. In this thesis, ammonium nitrate was selected in order to change the crystal habit and to hopefully induce new polymorph of AN which possessed special physicochemical properties. Firstly, engineering data of solubility, polymorphism, crystallinity, crystal habit and Form Space by solvent screening for Form IV ammonium nitrate (AN) was established. Secondly, a new cocrystal of AN and benzo-18-crown-6 (B18C6) was found by antisolvent method based on Form Space of AN and crown ether. Analytical tools such as LTDSC, TGA, FT-IR, OM, PXRD, SXD were used for understanding the supramolecular architectures and to ensure the stoichiometry of cocrystal. In the mean time, a spherical crystallization study for 1:1 cocrystal of AN-B18C6 was carried out based on Form Space of AN and B18C6. Finally, 1:1 cocrystal of AN-B18C6 was manufactured for burning characteristic, solubility and dissolution rate measurement to understand its properties. |
