In-air Polymerization and Crosslinking of Monomers during Electrospray Deposition

Electrospray deposition is a coating technique in which a solution is passed through a charged capillary, causing the solution to disperse into child droplets through a series of Coulomb fissions until the droplets reach a grounded target. This process is advantageous due to its ability to create nanostructured self-limiting electrospray deposition (SLED) coatings with certain solutions. A large disadvantage is its use of a large amount of solvent. This is wasteful and causes sprays to take a long time to deposit a film. To alleviate this, this study focuses on spraying monomers, which can be sprayed at a much higher weight percentage than their corresponding polymers, blended with a photoactivated polymerizing agent (Omnirad 819 and Esacure 1001M blends) and crosslinker (polyethylene glycol diacrylate) under ultraviolet light to create polymers mid-spray. It was found that the spray, using methyl methacrylate as the monomer, deposited a film consisting of oligomeric polymers that could be optionally crosslinked. Translating this to additional monomers will allow for a large reduction of waste and cost in the rapid, controlled coating of complex surfaces with hierarchical composites of tunable chemistry.