Thermoplastic sheets and articles with variable lofting capacity
AssigneeHanwha Azdel, Inc.
InventorsYune Seo Park, Anthony J Messina
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Abstract
Certain configurations are described herein of a thermoplastic sheet or article comprising a plurality of porous layers coupled to each other. In one configuration, the thermoplastic article may comprise a core layer, a first layer disposed on one surface of the core layer and a second layer disposed on another surface of the core layer. In some instances, each of the core layer, the first layer and the second layer may comprises a web of open celled structures formed by a plurality of reinforcing materials bonded together with a thermoplastic material and optionally may also include a lofting agent. The lofting capacity in different layers can be selected or tuned to provide desired properties.
Claims20
A method of forming a thermoplastic sheet comprising:
- forming a porous core layer by:
- combining a thermoplastic polyolefin resin material, reinforcing fibers and a lofting agent in an aqueous solution, wherein the lofting agent comprises at least one of expandable microspheres and expandable graphite materials;
- mixing the aqueous solution comprising the thermoplastic polyolefin resin material, reinforcing fibers and lofting agent to disperse the reinforcing fibers and the lofting agent in the thermoplastic polyolefin resin material to provide an aqueous foam dispersion;
- disposing the aqueous foam dispersion onto a moving wire screen forming element;
- removing liquid from the disposed aqueous foam using a vacuum to provide a formed porous core layer comprising a web comprising the thermoplastic polyolefin resin material, the reinforcing fibers and the lofting agent;
- forming a first porous layer by:
- combining a thermoplastic polyolefin resin material and reinforcing fibers in an aqueous solution;
- mixing the aqueous solution comprising the thermoplastic polyolefin resin material and the reinforcing fibers to disperse the reinforcing fibers in the thermoplastic polyolefin resin material to provide an aqueous foam dispersion;
- disposing the aqueous foam dispersion onto a moving wire screen forming element;
- removing liquid from the disposed aqueous foam using a vacuum to provide a formed first porous layer comprising a web comprising the thermoplastic polyolefin resin material and the reinforcing fibers;
- forming a second porous layer by:
- combining a thermoplastic polyolefin resin material and reinforcing fibers in an aqueous solution;
- mixing the aqueous solution comprising the thermoplastic polyolefin resin material and the reinforcing fibers to disperse the reinforcing fibers in the thermoplastic polyolefin resin material to provide an aqueous foam dispersion;
- disposing the aqueous foam dispersion onto a wire screen forming element;
- removing liquid from the disposed aqueous foam using a vacuum to provide a formed second porous layer comprising a web comprising the thermoplastic polyolefin resin material and the reinforcing fibers;
- disposing the formed first porous layer on a first surface of the formed porous core layer;
- and
- disposing the formed second porous layer on a second surface of the formed porous core layer to provide a thermoplastic sheet, wherein each of the formed porous core layer, the formed first porous layer and the formed second porous layer have a lofting capacity to alter a thickness of each of the formed porous core layer, the formed first porous layer and the formed second porous layer after lofting, wherein the lofting capacity of the formed porous core layer is different than the lofting capacity of the formed first porous layer at a first loft temperature and is different than the lofting capacity of the formed second porous layer at the first temperature so a resulting overall thickness in two or more of the formed porous core layer, the formed first porous layer and the formed second porous layer is different after lofting of the thermoplastic sheet at the first loft temperature.
Dependencies are inferred from the claim text.