Mesomorphic phase transitions and electro-optical properties of benzyl fluoroalkyl ether derivatives

Three series of liquid crystalline (LC) compounds containing benzyl fluoroalkyl ether groups (BFE), 4-n-propylbicyclohexylbenzyl fluoroalkyl ethers (3-C2BFE-X,X: fluoroalkyl group), 4-n-alkylcyclohexylbenzyl fluoroalkyl ethers (m-C1BFE-X, m: carbon no. ofn-alkyl group)and 4-n-alkoxyphenylbenzyl fluoroalkyl ethers (mO-BBFE-X), were newly synthesized for several fluoroalkyl groups (X) such asn-fluoroalkyl, branched fluoroalkyl, and 2-perfluoropropoxy-2,3,3,3-tetrafluoropropyl. The mesomorphic phase transitions and electro-optical properties were investigated for BFE. 3-C2BFE-X and m O-BBFE-X have SmB phases, and SmA and/or E phases, respectively, while m-C1BFE-X showed no mesophases. The occurrence and thermal stability of the LC phases are related to the chemical structures of the rigid core part and the terminal groups. The electro-optical properties were investigated for 15 wt% of BFE in host ZLI-1132. It was found that the BFE compounds have a good solubility of more than 15 wt% in ZLI-1132 and can be u...