MOISTURE SCAVENGING FILM STRUCTURES
In one aspect, a moisture scavenging film comprises a moisture barrier layer and a sealant layer comprising an active co-continuous polymer material, the sealant layer disposed on the moisture barrier layer. In another aspect, a method for producing flexible packaging film including a moisture scavenging film includes providing a moisture barrier layer and providing a sealant layer comprising an active co-continuous polymer material. The sealant layer is applied onto the moisture barrier layer while maintaining a co-continuous morphology of the active co-continuous polymer material. In yet another aspect, a packaging article formed from a moisture scavenging film is provided.
1 . A moisture scavenging film comprising:
a moisture barrier layer; and
a sealant layer comprising an active co-continuous polymer material, the sealant layer disposed on the moisture barrier layer, wherein the active co-continuous polymer material comprises:
a primary phase formed of a primary phase polymer material forming a first continuous phase;
a dispersed phase formed of an immiscible material forming a second continuous phase within the primary phase; and
an active component comprising particles formed of one or more moisture absorbing and/or moisture adsorbing materials disposed within at least the dispersed phase.
2 . The moisture scavenging film of claim 1 , further comprising an outer layer, wherein the moisture barrier layer is disposed between the outer layer and the sealant layer.
3 . The moisture scavenging film of claim 1 , wherein the sealant layer is a coextrusion comprising:
an outside sealant layer;
a middle sealant layer; and
an inside sealant layer;
wherein each of the outside sealant layer, middle sealant layer, and inside sealant layer, which may be the same or different, is formed of a composition comprising 0 to 100% by weight of the active co-continuous polymer material and 0 to 100% by weight of a diluent polymer composition, and further wherein the total weight of the active co-continuous polymer material in the sealant layer is in the range of 10% to 100% by weight based on the total weight of the sealant layer.
4 . The moisture scavenging film of claim 3 , wherein the total weight of the active co-continuous polymer material in the sealant layer is in the range of 25% to 70% by weight based on the total weight of the sealant layer.
5 . The moisture scavenging film of claim 3 , wherein the total weight of the active co-continuous polymer material in the sealant layer is in the range of 30% to 65% by weight based on the total weight of the sealant layer.
6 . The moisture scavenging film of claim 3 , wherein the diluent polymer composition comprises one or more additives selected from the group consisting of polymer stabilizers, antiblocking agents, anti-slip agents, and processing aids.
7 . The moisture scavenging film of claim 3 , wherein the diluent polymer composition comprises at least one polyolefin resin.
8 . The moisture scavenging film of claim 7 , wherein the diluent polymer composition comprises at least one polyolefin resin selected from the group consisting of a polyethylene resin, an ethylene C 6 -C 8 olefin copolymer resin, a metallocene-catalyzed polyethylene resin, a blown film resin, and any combination thereof.
9 . The moisture scavenging film of claim 1 , wherein the sealant layer is a coextrusion comprising:
an outside sealant layer comprising one or more diluent polymer resins and one or more optional additives;
a middle sealant layer 0 to 100% by weight of the active co-continuous polymer material and 0 to 100% by weight of the one or more diluent polymer resins and one or more optional additives; and
an inside sealant layer comprising 10-100% by weight of the active co-continuous polymer material and 0-90% by weight of the one or more diluent polymer resins and one or more optional additives.
10 . The moisture scavenging film of claim 9 , wherein, the total weight of the active co-continuous polymer material in the sealant layer is in the range of 10% to 100% by weight based on the total weight of the sealant layer.
11 . The moisture scavenging film of claim 1 , wherein the moisture scavenging film has a thickness in the range of 0.5 mil to 10 mil.
12 . The moisture scavenging film of claim 11 , wherein the moisture scavenging film has a thickness in the range of 1 mil to 6 mil.
13 . The moisture scavenging film of claim 1 , wherein the sealant layer comprises one or more extrusion coating layers disposed on the moisture barrier layer.
14 . A packaging article formed from the moisture scavenging film of claim 1 .
15 . A method for producing a flexible moisture scavenging packaging film, the method comprising:
providing a moisture barrier layer;
providing a sealant layer comprising an active co-continuous polymer material; and
applying the sealant layer onto the moisture barrier layer while maintaining a co-continuous morphology of the active co-continuous polymer material;
wherein the active co-continuous polymer material comprises:
a primary phase formed of a primary phase polymer material forming a first continuous phase;
a dispersed phase formed of an immiscible material forming a second continuous phase within the primary phase; and
an active component comprising particles formed of one or more moisture absorbing and/or moisture adsorbing materials disposed within at least the dispersed phase.
16 . The method of claim 15 , wherein providing a sealant layer comprises:
extruding the sealant layer with an extruder; and
during the extruding, controlling one or more of an extrusion temperature, an extrusion speed, and an extrusion time to maintain the co-continuous morphology of the active co-continuous polymer material.
17 . The method of claim 16 , wherein extruding the sealant layer comprises a multilayer coextrusion process.
18 . The method of claim 15 , wherein applying the sealant layer to the moisture barrier layer comprises a lamination process selected from the group consisting of extrusion lamination, adhesive lamination, extrusion coating, and coextrusion coating.
19 . The method of claim 15 , further comprising rolling the flexible moisture scavenging packaging film onto a roll and packaging the roll within a moisture-resistant packaging material.