Composition comprising non-newtonian fluids for hydrophobic, oleophobic, and oleophilic coatings, and methods of using the same
A composition for forming a protective coating on an electronic device that is in the form of a non-Newtonian fluid that exhibits both viscous and elastic properties, and that forms at least one coating that is hydrophobic, oleophobic, or oleophilic is disclosed. The viscous and elastic properties associated with the non-Newtonian fluid allows the composition to redistribute after being applied as a coating an electronic device. Methods for protecting an electronic device from liquid contaminants by applying the disclosed composition and electronic devices comprising the composition are also disclosed. An electronic device, such as a printed circuit board, having a film made of the composition is also disclosed.
1. A conformal coating on an assembled printed circuit board, the conformal coating made from a composition comprising:
(a) at least one hydrophobic fluid, and,
(b) one or more functionalized polysiloxanes, linear and cyclic silicones, styrene-ethylene/butylene-styrene or styrene-ethylene/propylene-styrene materials swelled with mineral oils or diesters, long chain fatty alcohols, functionalized fluoropolymers, functionalized or non-functionalized poly oligomeric silsesquioxanes, and polyolefins,
wherein the conformal coating is hydrophobic, electrically insulating, has a thickness ranging from 25 nm to 200 μm and exhibits viscoelastic or non-Newtonian properties when applied to the assembled printed circuit board.
2. The conformal coating of claim 1 , wherein said coating is able to redistribute after being applied to the substrate.
3. The conformal coating of claim 1 , wherein the composition further comprises one or more metal oxides, fumed functionalized silica, fluoropolymer particles, clay particles, mica, metal alkoxide particles, rare earth and transition metals, carbon-based materials selected from graphene, graphite, and carbon nanotubes, and metal organic frameworks.
4. The conformal coating of claim 1 , wherein the composition further comprises one or more additives selected from a surfactant, a dispersant, or a rheological modifier.
5. The conformal coating of claim 1 , wherein the composition is suspended in a carrier solvent comprised of at least one compound chosen from low molecular weight mineral oils, paraffins or iso-paraffins, alkanes or iso-alkanes, low molecular weight linear silicones or cyclic silicones, alkyl acetates, ketones, fully or partially halogenated hydrocarbons, or aldehydes.
6. The conformal coating of claim 1 , wherein the conformal coating increases resistance of the substrate to liquid or particulate contaminants or combinations thereof.
7. The conformal coating of claim 1 , which is oleophobic or oleophilic.