Use of benzoxazine as a structural thermal protective system (tps) and heat shield material

Abstract

A heat shield includes a substrate having a surface; and a benzoxazine composite material disposed onto the surface of the substrate, the benzoxazine composite material comprising a benzoxazine compound and a reinforcing fiber.

What is claimed is: 
     
         1 . A heat shield, comprising:
 a surface comprising a benzoxazine composite material, the benzoxazine composite material comprising a benzoxazine resin and a reinforcing fiber, the reinforcing fiber being present in an amount in a range from about 45 to about 70 weight % (wt. %) based on total weight of the benzoxazine composite material;   wherein the heat shield is a molded, free-standing structure without an additional supporting layer and forms at least part of a thermal protection system.   
     
     
         2 . The heat shield of  claim 1 , wherein the heat shield is attached to a spacecraft. 
     
     
         3 . The heat shield of  claim 1 , wherein the heat shield is a blast shield that protects from motor exhaust. 
     
     
         4 . The heat shield of  claim 1 , wherein the heat shield is a firewall. 
     
     
         5 . The heat shield of  claim 1 , wherein the heat shield is an ablative heat shield. 
     
     
         6 . The heat shield of  claim 1 , wherein the benzoxazine resin comprises a crosslinked bi-functional benzoxazine. 
     
     
         7 . The heat shield of  claim 1 , wherein the benzoxazine resin has the following structure: 
       
         
           
           
               
               
           
         
         wherein n is an integer from about 1 to about 2; R1 is a hydrogen, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C2-C20 alkenyl group, a substituted or unsubstituted C6-C20 aryl group, a substituted or unsubstituted C2-C20 heteroaryl group, a substituted or unsubstituted C4-C20 carbocyclic group, a substituted or unsubstituted C2-C20 heterocyclic group, a C3-C8 cycloalkyl group, a substituted or unsubstituted C1-C20 alkylene group, a substituted or unsubstituted C6-C20 arylene group, a substituted or unsubstituted C2-C20 heteroarylene group, a substituted or unsubstituted C1-C20 alkoxy group, an OH group, a halogen, or any combination thereof; and R2 is a single bond, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C2-C20 alkenyl group, a substituted or unsubstituted C6-C20 aryl group, a substituted or unsubstituted C2-C20 heteroaryl group, a substituted or unsubstituted C4-C20 carbocyclic group, a substituted or unsubstituted C2-C20 heterocyclic group, a C3-C8 cycloalkyl group, a substituted or unsubstituted C1-C20 alkylene group, a substituted or unsubstituted C6-C20 arylene group, a substituted or unsubstituted C2-C20 heteroarylene group, an oxygen, a sulfur, a carbonyl group, a S═O group, a O═S═O, or a combination thereof. 
       
     
     
         8 . The heat shield of  claim 1 , wherein the reinforcing fiber comprises carbon, silica, quartz, aramid, or any combination thereof. 
     
     
         9 . The heat shield of  claim 1 , wherein the benzoxazine resin comprises a monomer comprising a benzoxazine compound. 
     
     
         10 . The heat shield of  claim 1 , wherein the benzoxazine resin comprises a polymer comprising a benzoxazine compound. 
     
     
         11 . The heat shield of  claim 1 , wherein the benzoxazine resin comprises a crosslinked compound comprising a benzoxazine compound. 
     
     
         12 . The heat shield of  claim 1 , wherein the benzoxazine resin is a thermosetting resin. 
     
     
         13 . The heat shield of  claim 1 , wherein the benzoxazine composite material has a thickness in a range from about 0.1 millimeters (mm) to about 150 mm. 
     
     
         14 . The heat shield of  claim 1 , wherein the benzoxazine resin has the following structure: 
       
         
           
           
               
               
           
         
         wherein R1 is a hydrogen, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C2-C20 alkenyl group, a substituted or unsubstituted C6-C20 aryl group, a substituted or unsubstituted C2-C20 heteroaryl group, a substituted or unsubstituted C4-C20 carbocyclic group, a substituted or unsubstituted C2-C20 heterocyclic group, a C3-C8 cycloalkyl group, a substituted or unsubstituted C1-C20 alkylene group, a substituted or unsubstituted C6-C20 arylene group, a substituted or unsubstituted C2-C20 heteroarylene group, a substituted or unsubstituted C1-C20 alkoxy group, an OH group, a halogen, or any combination thereof; and R2 is a single bond, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C2-C20 alkenyl group, a substituted or unsubstituted C6-C20 aryl group, a substituted or unsubstituted C2-C20 heteroaryl group, a substituted or unsubstituted C4-C20 carbocyclic group, a substituted or unsubstituted C2-C20 heterocyclic group, a C3-C8 cycloalkyl group, a substituted or unsubstituted C1-C20 alkylene group, a substituted or unsubstituted C6-C20 arylene group, a substituted or unsubstituted C2-C20 heteroarylene group, an oxygen, a sulfur, halogen, a carbonyl group, a S═O group, a O═S═O, a halogen, or any combination thereof. 
       
     
     
         15 . The heat shield of  claim 1 , wherein the benzoxazine resin has the following structure: 
       
         
           
           
               
               
           
         
       
     
     
         16 . The heat shield of  claim 1 , wherein the benzoxazine composite material comprises syntactic foam. 
     
     
         17 . The heat shield of  claim 1 , wherein the benzoxazine composite material further comprises a polymer. 
     
     
         18 . The heat shield of  claim 1 , wherein the reinforcing fiber comprises a portion of a woven fabric, a nonwoven fabric, or a combination thereof. 
     
     
         19 . The heat shield of  claim 1 , wherein the benzoxazine composite material comprises about 25 to about 45 weight % of the benzoxazine resin. 
     
     
         20 . The heat shield of  claim 1 , wherein the benzoxazine composite material comprises about 35 to about 99 weight % of the benzoxazine resin.