(257g) Photochemical Bubble Generation on Polymer-Water Interface.

The ability to control solid-gas phase transitions using light as a stimulus has attracted significant interest in the field of materials science because it gives rise to a large volume change. In most cases, this transition is caused by photothermal heating of a volatile liquid. In this work, we use a photochemical mechanism for gas generation that is based on using organic azides undergoing UV photolysis to release gaseous nitrogen.

2-Anthraceneazide is doped into a 150µm thick polymer films that release nitrogen microbubbles on the film surface when irradiated in a water reservoir. The formation of nitrogen bubbles was observed using optical microscopy, and their size and distribution were characterized using image analysis. The effects of various irradiation conditions, such as irradiation time and light intensity, doping concentration of azide, and film surface on the formation of nitrogen bubbles were investigated. The results indicate that the size and distribution of the bubbles can be controlled by adjusting the irradiation conditions and film surface morphology.

The polymer film containing 2-anthracene azide, can be floated to the surface by the photoinduced bubble coating. The inherent property of a bubble is the air-water interface that attenuates ultrasound waves, making it a desirable option to use for acoustic blocking. Photochemical bubble generation provides a new avenue for the development of materials and devices that can be controlled by light and has potential applications in areas such as microfluidics, acoustic blocking, and nanotechnology.