Title: Photodeformable CLCP Material: Study on Photo-activated Microvalve Applications

Author: Maolin Chen, Haitao Huang, Yutian Zhu*, Zhao Liu*, Xing Xing, Futao Cheng, Yanlei Yu*

Journal: Appl. Phys. A, 2011, 102, 667-672

Abstract:

A kind of photodeformable polymer material, crosslinked liquid-crystalline polymer (CLCP) incorporated with azobenzene moieties, is studied as microvalve membrane actuator for microfluidic system applications. In the photomechanical analysis, the photo-induced bending effect of such polymer film is equivalent to a moment Tm and an axial force Nm applied on it, which are related to irradiation time and intensity of the driving UV light. A linear elastic beam model is established to calculate the maximal force that the valve actuator can resist and to analyze the deformation at any irradiation time in FEA. An experimental setup is built to record the flow rate in one operate cycle under various irradiation or preload conditions. The open time can reach 8 s and the close time 6 s. The results show that CLCP films have great potential in microvalve applications in biological engineering, drug delivering, etc. It has advantages of wireless, remote control and green energy.

Fulltext Link: https://link.springer.com/article/10.1007/s00339-010-6103-4

This study utilizes crosslinked liquid-crystalline polymer (CLCP) incorporated with azobenzene moieties as microvalve membrane actuator for microfluidic system applications. The photodeformability of azobenzene CLCP leads to the bending effect of polymer film and let the fluid flow. Based on the theory, a linear elastic beam model (consists of one CLCP film and two PMMA housings) is established and the maximal force that the valve actuator can resist is calculated, which finds out that the bending is related to irradiation time and intensity of the driving UV light. Furthermore, an experimental setup is built to record the flow rate under various irradiation or preload conditions. The results show that CLCP films, suitable for wireless, remote control and green energy, have great potential in microvalve applications in biological engineering, drug delivering, etc.