Aqueous polymer dispersions and products from those dispersions
View Patent ↗A method for forming a heat sealable coating on a substrate, wherein the substrate is formed from at least one oriented polymer is shown. The method includes depositing an aqueous polymer dispersion on the substrate, wherein the aqueous polymer dispersion includes (A) at least one thermoplastic resin; (B) at least one dispersing agent; and (C) water; wherein the dispersion has a pH of less than 12, and drying the dispersion to form a first layer.
1. A film layer comprising:
a substrate; and
a coating associated with said substrate; wherein the coating is derived from an aqueous dispersion comprising (A) at least one thermoplastic resin, wherein the thermoplastic resin comprises an interpolymer of ethylene with at least one comonomer selected from the group consisting of a C 4 -C 20 linear, branched or cyclic diene, vinyl acetate, and a compound represented by the formula H 2 C═CHR wherein R is a C 2 -C 20 linear, branched or cyclic alkyl group or a C 6 -C 20 aryl group; (B) at least one dispersing agent; and (C) water; wherein the dispersion had a pH in the range of 8 to 11.
2. The film layer of claim 1 , wherein the coating is heat sealable.
3. The film layer of claim 1 , wherein said substrate comprises a polymer selected from the group consisting of polyesters, polycarbonates, polyarylates, polyamides, polyimides, polyamide-imides, polyether-amides, polyetherimides, polyaryl ethers, polyarylether ketones, aliphatic polyketones, polyphenylene sulfide, polysulfones, polystyrenes and their derivatives, polyacrylates, polymethacrylates, cellulose derivatives, polyethylenes, polypropylene, other polyolefins, copolymers having a predominant olefin monomer, fluorinated polymers and copolymers, chlorinated polymers, polyacrylonitrile, polyvinylacetate, polyvinylalcohol, polyethers, ionomeric resins, elastomers, silicone resins, epoxy resins, and polyurethanes, miscible or immiscible polymer blends, and copolymers of any of the constituent monomers of any of the above-named polymers.
4. The film layer of claim 3 , wherein the substrate comprises at least one selected from the group consisting of polypropylene, polyamides, polyesters, polyethylene, and polystyrene.
5. The film layer of claim 1 , wherein the thermoplastic resin has a density between 0.85 and 0.90 g/cc.
6. The film layer of claim 2 , wherein the coating is characterized as having a heat seal initiation temperature of less than 80° C.
7. The film layer of claim 6 , wherein the coating is characterized as having a heat seal initiation temperature of less than 70° C.
8. An article comprising the film layer of claim 1 .
9. The film layer of claim 1 , wherein said film layer is biaxially oriented polypropylene.
10. The film layer of claim 1 , wherein said substrate is biaxially oriented polypropylene.