側鏈型雙桿狀氫鍵藍相液晶高分子之合成及其研究

Abstract

本論文中合成出三種具有壓克力基之羧酸單體，及三種不同的吡啶配體，利用羧酸與配體之超分子作用力，自組裝出不同形式的不對稱雙分子，探討不同分子配對對藍相之影響。 並利用照光聚合，得到一系列利用氫鍵自組裝成的側鏈型藍相液晶高分子。從實驗結果得知，在軟鏈上有對掌中心之含氟單環酸A*FB之單聚高分子，與軟鏈上不含對掌中心之吡啶配體Py6CB之配對，具有8.2 oC的藍相溫寬。 為了更進一步的改善此高分子系統，我們採取了兩種方式，一是利用含氟單環酸A*FB與不含氟單環酸A*B共聚合，二是將A*FB之單聚物配上兩種不同之吡啶配體Py6CB及Py6*CB，前者並未能有效拓寬藍相溫寬，而後者在Py6CB:Py6*CB為9:1時，可成功將藍相溫寬提升至10.4 oC。

We designed three carboxylic acid monomers A*B, A*FB and A*FBB containing acrylate group, and three different H-acceptors with pyridyl moiety. Due to the supramolecular forces between the H-donors and H-acceptors, a series of novel asymmetric hydrogen-bonded dimeric complexes were self-assembled successfully. In addition, a series of Bi-Mesogenic Side-Chain Polymers were prepared by photo-polymerization. The result demonstrates that the combination of homopolymer pA*FB and the H-acceptor Py6CB, which have no chiral center on the alkyl chain, could induce the blue phase BP III. The temperature range of the pA*FB/Py6CB system is 8.2 oC. To further improve the blue phase polymer system, we have taken two ways. One way is that we used the copolymerization of A*B and A*FB to get the system p(A*FB+A*B)/Py6CB. The other is mixing two H-acceptors Py6CB and Py6*CB to increase the overall chirality of the polymer system. The former is fail to broaden the temperature range of BP, but the pA*FB/(Py6CB+Py6*CB) system can increase the temperature range to 10.4 oC when the ratio of Py6CB to Py6*CB is 9:1.