Ultrasonic bonding of thermoplastic microfluidic devices

Abstract

Microfluidic devices see many advantages in using plastics that include low cost and easily available manufacturing methods, as compared to glass and silicon. Regardless of the bonding method, mass manufacturing development always imposes a unique set of challenge to overcome.

Ultrasonic welding offers advantages including compatibility with any thermoplastic, the ability to weld two different plastics or materials. Therefore the effects of ultrasonic welding of PMMA microfluidics were investigated using an adaptive one-factor-at-a-time method in this report. The parameters under investigation are vibration amplitude, welding pressure, welding time and holding time.

The optimised welding parameters had been identified and were used for further analysis on the dimension loss and bond strength. Defects were found on the microfluidic devices causing it to leak. However, good quality micro features and bond strength was observed from the optimised microfluidic devices tested.