Abstract: A method of printing a cellular solid by direct bubble writing comprises introducing an ink formulation comprising a polymerizable monomer and a gas into a nozzle, which includes a core flow channel radially surrounded by an outer flow channel. The ink formulation is directed into the outer flow channel and the gas is directed into the core flow channel. The ink formulation and the gas are ejected out of the nozzle as a stream of bubbles, where each bubble includes a core comprising the gas and a liquid shell overlying the core that comprises the ink formulation. After ejection, the polymerizable monomer is polymerized to form a solid polymeric shell from the liquid shell, and the bubbles are deposited on a substrate moving relative to the nozzle. Thus, a polymeric cellular solid having a predetermined geometry is printed.

Abstract: A method of printing a cellular solid (120) by direct bubble writing comprises introducing an ink formulation (102) comprising a polymerizable monomer and a gas (104) into a nozzle (106), which includes a core flow channel (108) radially surrounded by an outer flow channel (110). The ink formulation is directed into the outer flow channel (110) and the gas is directed into the core flow channel (108). The ink formulation (102) and the gas (104) are ejected out of the nozzle (106) as a stream of bubbles (112), where each bubble includes a core (114) comprising the gas and a liquid shell (116) overlying the core that comprises the ink formulation. After ejection, the polymerizable monomer is polymerized to form a solid polymeric shell (118) from the liquid shell (116), and the bubbles are deposited on a substrate (122) moving relative to the nozzle (106). Thus, a polymeric cellular solid (120) having a predetermined geometry is printed.

Abstract: A method of printing a cellular solid (120) by direct bubble writing comprises introducing an ink formulation (102) comprising a polymerizable monomer and a gas (104) into a nozzle (106), which includes a core flow channel (108) radially surrounded by an outer flow channel (110). The ink formulation is directed into the outer flow channel (110) and the gas is directed into the core channel (108). The ink formulation (102) and the gas (104) are ejected out of the nozzle (106) as a stream of bubbles (112), where each bubble includes a core (114) comprising the gas and a liquid shell (116) overlying the core that comprises the ink formulation. After ejection, the polymerizable monomer is polymerized to form a solid polymeric shell (118) from the liquid shell (116), and the bubbles are deposited on a substrate (122) moving relative to the nozzle (106). Thus, a polymeric cellular solid (120) having a predetermined geometry is printed.