A process analysis for microchannel deformation and bonding strength by in-mold bonding of microfluidic chips

A novel combination of thermal bonding and in-mold assembly technology was created to produce microfluidic chips out of polymethylmethacrylate (PMMA), which is named in-mold bonding technology. In-mold bonding experiments of microfluidic chips were carried out to investigate the influences of bonding process parameters on the deformation and bonding strength of microchannels. The results show that bonding temperature has the greatest impact on the deformation of microchannels, while bonding pressure and bonding time have more influence on deformation in height than in top width. Considering the bonding strength, the bonding temperature and the bonding pressure have more impact than the bonding time. The time is crucial for the sealing of the chips. By setting the bonding parameters reasonably, the microchannel deformation is <10%, while the bonding strength of the chips is 350 kPa. The production cycle of the chip is reduced to <5 min.