Barrier coating of a mixture of cured and uncured elastomeric polymers and a dispersed layered filler in a liquid carrier and coated articles

A method of producing a barrier coating film comprising:

• a) mixing pre-vulcanized elastomers and non-vulcanized elastomers to form an elastomeric polymer composition;
• b) modifying substantially exfoliated silicate filler material not functionalized with organic cations with an acid or base to form acid or base modified or treated silicate filler with an aspect ratio greater than about 25:
• c) applying to a substrate an aqueous dispersion comprising the elastomeric polymer composition, at least one additive, selected from the group consisting of surfactants, emulsifiers, anti-foaming agents, dispersing agents, wetting agents, leveling agents and thickeners, and the modified or treated silicate filler, wherein the modified or treated silicate filler is present in the dispersion at less than 60% of the solid content;
• and
• d) drying the dispersion to a barrier coating having the same polymer to filler ratio as in said dispersion wherein the coating exhibits an at least 50-fold reduction in gas permeability as compared with a coating formed of said elastomeric polymer composition alone and said coating retains its barrier properties under strain and the mixture of pre-vulcanized and non-vulcanized elastomers is effective to increase the strain resistance of the coating as compared with a like coating containing either pre-vulcanized elastomers alone or non-vulcanized elastomers alone, such that the coating has a strain to first damage of at least 10% biaxial elongation at 0% RH.