Solvent/non-solvent-based approach in MAPLE deposition of EVA coatings

A new approach to target preparation was applied for MAPLE deposition of poly(ethylene-co-vinyl acetate) (EVA) coatings. By adding a non-solvent (acetone) to EVA-chloroform solution, an almost threefold increase in the deposition efficiency was achieved and semicrystalline coatings with a modified surface morphology and high preservation of chemical structure were obtained. The chemical structure of the coatings was determined using IR and XPS techniques, the morphology and topography were characterized by AFM, SEM, XRD and profilometry. It is postulated that the addition of a non-solvent to the solvent mixture improves the spatial conformation of high molecular weight polymer chains, leading to lower entanglement and lower tendency to form larger clusters that have a detrimental effect on the coating morphology and composition. This hypothesis is supported by analysis of the rheological properties of the solutions. A change in the spatial conformation and physical interactions of EVA macromolecules was evaluated by viscosity and dynamic light scattering (DLS) measurements. The approach proposed can be applied to all oligomeric and polymeric materials to diminish the viscosity and entanglement of molecules to increase the deposition efficiency and represents an important step in the scaling-up of the MAPLE process.

Automated summary

A new approach was developed for the preparation of poly(ethylene-co-vinyl acetate) (EVA) coatings using a Modified Atmospheric Pressure Laser Enhanced Deposition (MAPLE) technique. By adding acetone as a non-solvent to the EVA-chloroform solution, the deposition efficiency was significantly increased compared to traditional methods. The resulting coatings exhibited modified surface morphology and high preservation of chemical structure. This approach can be applied to various oligomeric and polymeric materials to enhance deposition efficiency, making it a crucial step in scaling-up the MAPLE process.