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

[Display omitted] •An increased deposition efficiency of MAPLE process by the non-solvent addition.•Deposition of high molecular weight EVA copolymer with well-preserved chemical structure.•Crystallization of the coatings induced by self-organization of EVA copolymer in three component system, i.e. solvent/non-solvent/polymer. 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.