oplossingcasting

Oplossingcasting, or solution casting, is a film-forming technique used to produce solid polymer films by dissolving a polymer in a suitable volatile solvent to form a homogeneous solution, which is then spread or cast onto a flat substrate and allowed to dry as the solvent evaporates.

The process typically involves preparing a polymer solution with a controlled concentration and temperature, removing any trapped air or bubbles, and applying the solution to a substrate such as glass or silicon using a casting knife, doctor blade, or bar coater. The solvent is gradually evaporated under ambient or controlled conditions, sometimes with temperature or humidity control, to form a continuous, freestanding or substrate-bound film. Optional post-treatment steps may include annealing, conditioning, or solvent exchange to tailor film properties.

Materials used in oplossingscasting include a wide range of polymers such as polyvinylpyrrolidone (PVP), polymethyl methacrylate (PMMA), polyvinylidene fluoride (PVDF), polystyrene, and more specialized polymers. Suitable solvents are chosen based on polymer solubility, volatility, and compatibility, with common examples including acetone, toluene, chloroform, DMF, THF, and ethanol. The method emphasizes simplicity and relatively low equipment cost, but relies on careful solvent selection to minimize residual solvent, environmental impact, and potential adverse effects on polymer morphology.

Applications span polymer membranes for filtration and separation, protective and functional coatings, electronics, and packaging films. Advantages include the ability to form uniform films over large areas and to control thickness through solution concentration and spreading parameters; limitations involve solvent management, drying conditions, and potential solvent-related health and safety concerns.