US 11,999,834 B2
Precursor compositions for a protective article, protective articles comprising a reaction product of the precursor composition, related aerospace structures, and related methods
Cameron Hilton, Pleasant Grove, UT (US); Benjamin W. C. Garcia, Tremonton, UT (US); Matthew Armentrout, Salt Lake City, UT (US); Steven F. Stone, Irvine, CA (US); Christopher Deemer, Sandy, UT (US); and Brian Barber, Xenia, OH (US)
Assigned to Northrop Grumman Systems Corporation, Falls Church, VA (US)
Filed by Northrop Grumman Systems Corporation, Falls Church, VA (US)
Filed on Jun. 19, 2019, as Appl. No. 16/446,038.
Prior Publication US 2020/0399436 A1, Dec. 24, 2020
Int. Cl. C08J 9/00 (2006.01); B32B 5/18 (2006.01); B32B 5/32 (2006.01); B64C 7/00 (2006.01); C08J 9/228 (2006.01)
CPC C08J 9/0085 (2013.01) [B32B 5/18 (2013.01); B32B 5/32 (2013.01); B64C 7/00 (2013.01); C08J 9/0066 (2013.01); C08J 9/0071 (2013.01); C08J 9/228 (2013.01); B32B 2266/0207 (2013.01); B32B 2605/18 (2013.01); C08J 2203/22 (2013.01); C08J 2333/08 (2013.01)] 26 Claims
OG exemplary drawing
 
19. An aerospace structure comprising:
a protective article on at least a portion of an external surface of an aerospace structure, the protective article comprising a foamed protective material comprising a reaction product of a precursor composition comprising:
a primary polymer in an amount of from about 65.0% by weight to about 80.0% by weight based on a total weight of the precursor composition, wherein the primary polymer is an acrylic ethylene monomer (AEM);
expandable microspheres;
a strengthening additive in an amount of from about 2% by weight to about 20% by weight based on the total weight of the precursor composition, wherein the strengthening additive comprises one or more of nanotubes, platelets, rods, or disks of one or more of carbon, glass, metal, or ceramic;
a peroxide curing agent and a peroxide cure accelerator; and
one or more additional additives comprising a thermal ablation additive, a reflectivity additive, or an x-ray absorption additive; and
wherein the precursor composition is free of an amine curing agent.