Analysis of Surface Properties of DPPC/Long-Chain Alcohol Langmuir-Blodgett Films

• Main Authors: Lin, Cheihung, 林志宏
• Other Authors: Yu Min Yang
• Format: Others
• Language: zh-TW
• Published: 1998
• Online Access: http://ndltd.ncl.edu.tw/handle/02211545249630620333

碩士 === 國立成功大學 === 化學工程學系 === 86 === Abstract In this study, mixed DPPC/long-chain alcohol Langmuir-Blodgett (LB) films were deposited at different surface pressures, and the contact angles of water on the LB films were measured by using a dynamic contact angle analyzer. The goal is to investigate the effects of monolayer composition at the air/ water interface and deposited surface pressure on the wettability of the LB film surface. The results show that when the LB film is deposited at the surface pressure of 25 mN/ m, the monolayer composition has no effects on the advancing contact angle of water on the LB film. However, at the deposited surface pressure of 35 mN/m, the advancing contact angle increases with the mole fraction of DPPC, except for the pure DPPC LB film. Moreover, based on the FTIR analysis, one can find that there is no relationship between the molecular orientation and the wettability of the LB film. We also prepare the LB films of long-chain alcohol and find that the wettability of the LB film is not affected by the chain length, but increases with deposited surface pressure. When the LB films are dried under different conditions, the advancing contact angle of water on the LB film surfaces can change significantly from 30o to 112 o.