Rocket assembly ablative materials formed from, as a precursor, staple cellulosic fibers, and method of insulating or thermally protecting a rocket assembly with the same
View Patent ↗A rocket motor assembly is insulated or thermally protected with a rocket motor ablative material formed from a prepreg. The prepreg contains at least an impregnating resin matrix and, as a precursor prior to carbonization, carded and spun staple cellulosic fibers. When patterned and carbonized, the rocket motor ablative material can be lined or otherwise placed into a rocket motor assembly, such as between the solid propellant and case, in the bulk area of the exit nozzle liner, or at susceptible portions of a re-entry vehicle, such as the nose cone.
1. A method for insulating or thermally protecting a rocket motor assembly comprising a rocket motor casing containing a solid propellant, and a nozzle assembly coupled to the rocket motor casing, said process comprising (a) forming a rocket motor insulation from a prepreg comprising at least one resin matrix impregnated into a carbonized reinforcement, the carbonized reinforcement being formed from, as a precursor prior to carbonization, carded and yarn-spun staple cellulosic fibers and (b) insulating a portion of the rocket motor assembly with the rocket motor ablative material.
2. The process of claim 1 , wherein the staple cellulosic fibers comprise non-solvent-spun rayon fibers.
3. The process of claim 2 , wherein the non-solvent-spun rayon fibers have an average length in a range of from 38 mm to 225 mm, and are spun into yarn having a denier per fiber in a range of from 1.5 dpf to 9.0 dpf.
4. The process of claim 1 , wherein the staple cellulosic fibers are formed from a cellulose-derivative.
5. The process of claim 1 , wherein the staple cellulosic fibers are untreated.
6. The process of claim 1 , wherein said insulating comprises applying the rocket motor ablative material between the solid propellant and the casing surrounding the solid propellant.
7. The process of claim 1 , wherein said insulating comprises applying the ablative material as a bulk ablative material of an exit nozzle liner.
8. The process of claim 1 , wherein said insulating comprises applying the ablative material as a bulk ablative material of a reentry vehicle nose cone.
9. The process of claim 1 , further comprising carbonizing the prepreg at at least 1350° C.
10. The process of claim 1 , wherein the prepreg comprises 31.0-36.0 wt % phenolic resin, 13.0-17.5 wt % carbon black filler, and 46.5 to 56.0 wt % carbon fabric.
11. Rocket motor insulation comprising a prepreg, said prepreg comprising at least one carbonized reinforcement structure impregnated with at least one resin, said reinforcement structure being formed from, as a precursor prior to carbonization, carded and spun cellulosic fibers.
12. The rocket motor insulation of claim 11 , wherein the staple cellulosic fibers comprise non-solvent-spun rayon fibers.
13. The rocket motor insulation of claim 12 , wherein the non-solvent spin rayon fibers have an average length in a range of from 38 mm to 225 mm, and the yarn has a denier per fiber in a range of from 1.5 dpf to 9.0 dpf.
14. The rocket motor insulation of claim 11 , wherein the staple cellulosic fibers are formed from a cellulosic derivative.
15. The rocket motor insulation of claim 11 , wherein the staple cellulosic fibers are untreated.
16. A rocket motor assembly comprising the insulation of claim 11 .
17. The rocket motor assembly of claim 16 , wherein the insulation is constructed and arranged as a bulk insulation of an exit nozzle liner.
18. The rocket motor assembly of claim 16 , wherein the insulation is constructed and arranged as a bulk insulation of a re-entry vehicle nose cone.
19. The rocket motor assembly of claim 16 , wherein the insulation is interposed between a solid propellant and casing of the rocket motor assembly.
20. The process of claim 1 , wherein said insulating comprises lining the portion of the rocket motor assembly.
21. A method of thermally protecting a vehicle, the method comprising;
forming an ablative material comprising at least one resin matrix impregnated into a carbonized reinforcement including forming the at least one carbonized reinforcement from, as a precursor prior to carbonization, carded and yarn-spun staple cellulosic fibers; and
insulating at least a portion of the vehicle including applying the ablative material to the at least a portion of the vehicle.
22. A method of thermally protecting a surface exposed to combustion products, the method comprising:
forming an ablative material comprising at least one resin matrix impregnated into a carbonized reinforcement including forming the at least one carbonized reinforcement from, as a precursor prior to carbonization, carded and yarn-spun staple cellulosic fibers; and
insulating at least a portion of a surface along an expected flow path of the combustion products, insulating the at least a portion of the surface including applying the ablative material to the at least a portion of the surface along the expected flow path.