HIGH TEMPERATURE NON-CROSSLINKED POLYETHYLENE-BASED FOAM AND METHOD OF MAKING THE SAME

1 . A high-temperature linear low density polyethylene-based foam comprising linear low density polyethylene foam, wherein the high-temperature linear low density polyethylene-based foam has a maximum operating temperature of about 220° F., wherein the low density polyethylene-based foam is formed from an linear low density polyethylene-based resin that is irradiated such that a melt index of the linear low density polyethylene-based resin is reduced from between 15 and 25 at 190° C. to between 0.7 and 5.0 at 190° C.

2 . The high-temperature linear low density polyethylene-based foam as claimed in claim 1 , wherein the linear low density polyethylene-based foam has a density in the range of from 0.6 to 10.0 lbs/ft 3 .

3 . The high-temperature linear low density polyethylene-based foam as claimed in claim 2 , wherein the high-temperature linear low density-based foam has density has a density in the range of from 1.0 to 2.0 lbs/ft 3 .

4 . The high-temperature linear low density polyethylene-based foam as claimed in claim 1 , wherein the linear low density polyethylene includes a long chain branch molecular structure.

5 . The high-temperature linear low density polyethylene-based foam as claimed in claim 1 , wherein the high temperature linear low density polyethylene-based foam is a non-crosslinked foam.

6 . The high-temperature linear low density polyethylene-based foam as claimed in claim 1 , further comprising one or more additives selected from the consisting of flame retardants, color pigments, nucleating agents, diffusion blockers, and blowing agents.

7 . The high-temperature linear low density polyethylene-based foam as claimed in claim 1 , wherein the high-temperature linear low density polyethylene-based foam meets the ASTM C411 standard for hot-surface performance of high-temperature thermal insulation when tested at temperatures up to about 220° F.

8 . A method of manufacturing a high-temperature linear low density polyethylene-based foam comprising:

processing a linear low density polyethylene resin to produce a long branch molecular structure in the linear low density polyethylene resin, wherein the linear low density polyethylene resin has a melt index of between 15 and 25 at 190° C. and is irradiated until the melt index of the linear low density polyethylene resin is reduced to between 0.7 and 5.0 at 190° C.; and

manufacturing a high-temperature linear low density polyethylene-based foam from the processed linear low density polyethylene resin.

9 . The method of claim 8 , wherein processing the linear low density polyethylene resin comprises irradiating the linear low density polyethylene resin.

10 . The method of claim 9 , wherein the irradiation is carried out without eliminating the thermoplastic property of the linear low density polyethylene resin.

11 . The method of claim 8 , wherein the linear low density polyethylene resin is a linear low density polyethylene resin having a melt temperature of about 255° F.

12 . The method of claim 8 , wherein manufacturing a high temperature linear low density polyethylene-based foam from the processed linear low density polyethylene comprises a step of melting the processed linear low density polyethylene resin.

13 . The method of claim 112 , wherein manufacturing a high temperature linear low density polyethylene-based foam from the processed linear low density polyethylene further comprises the steps of:

injecting a blowing agent into the melted linear low density polyethylene resin;

extruding the melted linear low density polyethylene resin; and

passing the melted linear low density polyethylene resin through a die.

14 . The method of claim 12 , wherein manufacturing the high-temperature linear low density polyethylene-based foam from the processed polyethylene resin comprises using manufacturing equipment configured to manufacture low density polyethylene foam.