New PEG‐Modified Ladder‐Like Silsesquioxane as an Antifoaming Agent

Abstract New ladder‐like silsesquioxane modified with polyethylene glycol as an antifoaming agent based on silicone was synthesized. Silsesquioxane containing polyethylene glycol fragments was successfully fabricated through the reaction of silsesquioxane bearing cyanuric chloride as a linker molecule with polyethylene glycol groups. The structure of the modified silsesquioxane was characterized by middle infrared spectroscopy (MIR), proton nuclear magnetic resonance ( 1 H‐NMR), field emission scanning electron microscopy (FE/SEM), energy‐dispersive X‐ray spectroscopy (EDX), and transmission electron microscopy (TEM). In addition, thermogravimetric analysis (TGA) showed that the new silsesquioxane had excellent thermal stability. This modified structure was used as antifoaming agent for prevention of carryover in boiler systems. Furthermore, the results indicate that the combination of silsesquioxane and polyethylene glycol groups tends to increase the antifoaming properties of the new silicone‐based agent.