Pressure-sensitive adhesives including expandable graphite
A building material comprising a substrate layer and a pressure-sensitive adhesive layer, where the pressure-sensitive adhesive layer includes expandable graphite.
1. A method of preparing a building material, the method comprising the steps of:
i. providing a polymeric sheet having first and second planar surfaces;
ii. extruding a hot-melt pressure-sensitive adhesive to provide a pressure-sensitive adhesive sheet having first and second planar surfaces;
iii. dropping expandable graphite on to the first planar surface of the pressure-sensitive adhesive sheet; and
iv. applying the first planar surface of the pressure-sensitive adhesive sheet to the second planar surface of the polymeric sheet.
2. The method of claim 1 further comprising the step of applying a release liner to the second planar surface of the pressure-sensitive adhesive sheet.
3. The method of claim 1 wherein the hot-melt pressure-sensitive adhesive includes a polystyrene block copolymer.
4. The method of claim 1 wherein the hot-melt pressure-sensitive adhesive includes butyl rubber.
5. The method of claim 1 wherein the step of applying the first planar surface of the pressure-sensitive adhesive sheet to the second planar surface of the polymeric sheet forms an interface where the pressure-sensitive adhesive sheet contacts the second planar surface of the polymeric sheet.
6. The method of claim 5 , wherein the step of dropping the expandable graphite on the first planar surface of the pressure-sensitive adhesive sheet forms a concentrated region of the expandable graphite proximate the interface.
7. The method of claim 1 wherein the hot-melt pressure-sensitive adhesive is an extrudable hot-melt pressure-sensitive adhesive.
8. The method of claim 7 further comprising the step of applying a release liner to the pressure-sensitive adhesive sheet.