Nonwoven mat with reduced permeability and increased caliper
AssigneeOwens Corning Intellectual Capital, LLC
InventorJianhui Wu
Life of this patent
Estimating the term…
Abstract
A nonwoven mat and a method of making a nonwoven mat are provided. The nonwoven mat includes reinforcing fibers and a binder composition that includes a polycarboxy polymer and polymer microspheres. The binder composition may also include low-density fibers, such as microfibrillated cellulose fibers. The polymer microspheres have a thermoplastic shell that encapsulates a blowing agent. The thermoplastic shell has magnesium hydroxide on its outer surface. The components of the binder composition interact with one another and/or the reinforcing fibers to form a nonwoven mat having a less permeable structure and a higher caliper.
Claims13
A nonwoven mat comprising:
- a plurality of reinforcing fibers;
- and
- a binder composition comprising, on a dry weight basis, 70% to 95% by weight of a polycarboxy polymer and 1% to 30% by weight of a plurality of polymer microspheres, wherein the binder composition binds the plurality of reinforcing fibers together,
- wherein each of the polymer microspheres comprises a thermoplastic shell encapsulating a blowing agent, and magnesium hydroxide distributed throughout the thermoplastic shell, and
- wherein the nonwoven mat has an air permeability that is 5% to 35% lower than an otherwise identical nonwoven mat that does not include the polymer microspheres.
A method of forming a nonwoven mat, the method comprising:
- a) depositing an aqueous reinforcing fiber slurry onto a processing line to form a wet laid mat having a first major surface and a second major surface;
- b) applying a binder composition to at least one of the first major surface and the second major surface of the wet laid mat, wherein the binder composition comprises, on a dry weight basis, 70% to 95% by weight of a polycarboxy polymer and 1% to 30% by weight of a plurality of polymer microspheres, wherein each of the polymer microspheres comprises a thermoplastic shell encapsulating a blowing agent, and magnesium hydroxide distributed throughout the thermoplastic shell;
- and
- c) heating the wet laid mat to cure the binder composition and cause the polymer microspheres to expand, thereby forming the nonwoven mat,
- wherein the nonwoven mat has an air permeability that is 5% to 35% lower than an otherwise identical nonwoven mat that does not include the polymer microspheres.
Dependencies are inferred from the claim text.