INORGANIC/ORGANIC HYBRID NANOLAMINATE BARRIER FILM
An inorganic/organic hybrid nanolaminate barrier film has a plurality of layers of an inorganic material that alternate with a plurality of layers of an organic material. Such a barrier film can be fabricated using nanocomposite self-assembly techniques based on sol-gel chemistry.
1 . A method for making an inorganic/organic hybrid nanolaminate barrier film, comprising:
combining an alkoxide, an alcohol, water dilute HCl and heating the resulting mixture. Introducing a coupling agent to the mixture,
introducing a surfactant to the mixture in a quantity sufficient that the initial surfactant concentration is below the critical micelle concentration;
adding to the mixture one or more polymer precursors suitable for the formation of a polymer selected from the group of, polyethylene naphthalate (PEN), polyether etherketone (PEEK), polyether sulfone (PES), fluorinated or non-fluorinated styrene polymer precursors, fluorinated or non-fluorinated methyl styrene polymer precursors, fluorinated or non-fluorinated (meth)acrylate polymer precursors, and combinations and/or derivatives of two or more of these precursors;
adding a cross-linker agent and an initiator to the mixture;
coating a substrate with the mixture; and
allowing the alcohol to evaporate so that the sol forms a film having alternating organic and inorganic layers.
2 . The method of claim 1 further comprising incorporating one or more hydrophobic groups into the polymer precursors or eliminating one or more hydrophobic groups from the polymer precursors to increase and/or decrease the hydrophobicity of the organic layers.
3 . The method of claim 2 wherein the one or more hydrophobic groups are selected from the group of non-polar hydrophobic groups, methyl groups, benzyl (aromatic) groups, PO 4 3− , SO 4 2− , CH 3 COOO − , Br − , NO − , ClO 4 − , I − , SC − anions, NH 4 + , Rb + , K + , Na + , Cs + , Li + , Mg 2+ , Ca 2+ , Ba 2+ cations, tryptophan, isoleucine, phenylalanine, tyrosine, leucine, valine, methionine, alanine
4 . The method of claim 3 wherein the surfactant includes one or more Gemini surfactants.
5 . The method of claim 1 wherein the alkoxide includes tetraethylorthosilicate (Si(OCH 2 CH 3 ) 4 and the alcohol is ethanol.
6 . The method of claim 5 wherein in molar ratios of the tetraethylorthosilicate, ethanol, water, and HCl are present in the mixture in molar ratios of 1:3.8:1:5×10 −5 respectively.
7 . The method of claim 6 , wherein the coupling agent is 7-octenlytrimethoxysilane, or methacryloxypropyl trimethoxysilane.
8 . The method of claim 7 wherein the surfactant is cetyltrimethylammonium bromide.
9 . The method of claim 1 wherein the one or more polymer precursors include 2,6-Dimethylnaphthalene, or a set of monomers such as bisphenol A and di-para-fluorophenylsulfone.
10 . The method of claim 1 , further comprising annealing the film at a temperature of about 125° to about 150° C. or greater and/or below the lowest decomposition temperature of any of the organic materials in the film.
11 . The method of claim 1 wherein coating a substrate with the mixture includes depositing the mixture on the substrate by dip coating, spin coating, spray coating, web coating, or microgravure web coating.