BURN PROTECTIVE MATERIALS
A method is described for reducing the afterflame of a flammable, meltable material. A textile composite is described comprising an outer textile comprising a flammable, meltable material, and a heat reactive material comprising a polymer resin-expandable graphite mixture.
1 . A method for reducing the afterflame of a flammable, meltable material to less than 20 seconds, comprising:
a) providing an outer textile comprising a flammable, meltable material, and comprising an inner side and an outer side,
b) providing a heat reactive material comprising a polymer resin-expandable graphite mixture, wherein the expandable graphite has an expansion of at least 900 μm upon heating to 280° C.,
c) applying the polymer-expandable graphite mixture to the inner surface of the outer textile material to form the heat reactive material,
wherein the outer side of the outer textile is exposed to a flame.
2 . The method of claim 1 wherein the polymer resin comprises thermoplastic polymers.
3 . The method of claim 1 wherein the polymer resin comprises a crosslinkable polyurethanes.
4 . The method of claim 1 wherein the polymer resin-expandable graphite mixture is applied to the inner surface of the outer textile discontinuously.
5 . The method of claim 1 wherein the polymer-expandable graphite mixture is applied to the inner surface of the outer textile as discrete, discontinuous dots.
6 . The method of claim 1 wherein the flammable, meltable material comprises nylon or polyester.
7 . The method of claim 1 wherein the outer textile has a weight between 1 oz/yd2 to 10 oz/yd2.
8 . The method of substantially increasing the break-open time of a textile composite having an outer textile comprising a meltable material comprising the steps:
a) providing an outer textile comprising a meltable material, comprising an inner surface and an outer surface;
b) providing a thermally stable convective barrier;
c) providing a heat reactive material between the convective barrier and the inner surface of the outer textile, by applying a polymer resin-expandable graphite mixture wherein the expandable graphite has an expansion of at least 900 μm upon heating to 280° C.,
wherein the textile composite has a break-open time that is at least 20 seconds greater than the outer textile without a heat reactive material.
9 . The method of claim 8 wherein the polymer resin-expandable graphite mixture is applied as discrete dots that cover an area of less than 50%.
10 . The method of claim 8 wherein the polymer resin-expandable graphite mixture bonds the outer textile and the convective barrier together.
11 . The method of claim 8 wherein the heat reactive material comprises less than 50 wt % of the expandable graphite.
12 . The method of claim 8 wherein the break-open time of the textile composite is greater than 30 seconds.
13 . The method of claim 8 wherein the afterflame of the textile composite is less than 10 seconds.
14 . A method of reducing the percent burn of a garment in a 4-second Pyroman exposure by at least 10% comprising
a) providing a textile composite comprising
an outer textile comprising a meltable material,
a thermally stable convective layer, and
a heat reactive material between the outer textile and the thermally stable convective barrier, wherein the heat reactive material comprises a polyurethane-expandable graphite mixture
b) constructing a garment wherein the outer surface of the outer textile is oriented toward a flame, and
c) subjecting the garment to a 4 second Pyroman exposure test,
wherein the percent body burn is decreased by at least a 10 percentage points in a 4-second exposure to Pyroman compared to a garment without the heat reactive material between the outer textile and the thermally stable convective barrier.
15 . An article comprising a flame resistant textile composite comprising
a) an outer textile comprising a meltable material,
b) a heat reactive material comprising a polymer resin and an expandable graphite that expands at least 900 μm upon heating to 280° C., the heat reactive material applied to one surface of the meltable textile and,
c) a thermally stable convective barrier adjacent the heat reactive material,
wherein the article has a break-open time at least 30 seconds greater than a substantially similar article without the heat reactive material between the outer textile and the thermally stable convective barrier.
16 . The article of claim 15 wherein the meltable textile is flammable.
17 . The article of claim 15 wherein the flame resistant textile composite has an afterflame of less than 10 seconds.
18 . The article of claim 15 wherein the thermally stable convective barrier is bonded to the meltable textile by the heat reactive material, and the heat reactive material covers an area of less than 80%.
19 . The article of claim 15 wherein the flame resistant textile composite has an MVTR>1000.
20 . The article of claim 15 further comprising a thermally stable textile backer disposed adjacent to the convective barrier on the side opposite the heat reactive material.
21 . A garment, tent, glove or footwear article comprised of the flame resistant textile composite of claim 15 .
22 . The article of claim 15 , wherein the flame resistant textile composite exhibits no melt-dripping during the horizontal flame test.
23 . A flame resistant textile composite article comprising
a) a meltable flammable textile and
b) a heat reactive material comprising a polymer resin and an graphite that expands at least 900 μm upon heating to 280° C., the heat reactive materials disposed on one surface of the meltable textile and,
wherein the article has an after-flame of less than 20 seconds.
24 . The article of claim 23 wherein the polymer resin-expanded graphite mixture expands to form a plurality of tendrils comprising expanded graphite wherein the tendrils have an aspect ratio of at least 5 to 1.