Polyformaldehyde-based microfluidics and application in enhanced oil recovery

Polyformaldehyde (POM) is one of the most commonly used engineering thermoplastics that has been widely used in the industry as well as in our daily life. Compared with other thermoplastics, POM has a relatively high thermal resistance and self-lubricating properties. In this study, the POM was used as the bulk material for microfluidic devices, with the microchannels directly laser ablated on the surface of POM plates. The profile of the microchannels with various CO2 laser energy and scan speed was also studied in detail. To enclose the channel, a layer of adhesive polyester film was attached to the surface of the POM plate to seal the fabricated microchannels, and the bonding strength was enhanced with a further compression procedure and then tested with a burst opening method. With the help of the high thermal resistance of POM, an enhanced oil recovery (EOR) test under high temperature was conducted in this study based on the POM-based microfluidic device to mimic the underground oil recovery process in the porous sandstone structure.