US 7,410,607 B2 · Method of insulating a case of a solid propellant rocket motor

Abstract

This method permits manufacturing EPDM rocket motor insulation in which carbon fibers are dispersed and immobilized in the EPDM polymeric matrix but are not excessively fractured or fragmentized, i.e., broken into smaller fragments, when encountering degrees of shear necessary to homogeneously or otherwise distribute or disperse the carbon fibers in the EPDM polymeric matrix. The method is substantially solvent free and is performed via distributive/reduced shear mixing to distribute the fragile carbon fibers into a rubber matrix without excessive damage. According to one embodiment, at least about 50% of the elastomer composition introduced into the mixing apparatus is liquid EPDM terpolymer having sufficiently low molecular weight and high diene content to permit dispersion of the carbon fibers in the EPDM without substantial fragmentation of the fibers. According to another embodiment, mixing takes place in a kneader capable of rotating a screw having a discontinuous screw thread about the screw axis while superimposing an axially reciprocating stroke to the screw. The kneader imparts low shear distributive mixing of the carbon fibers in the EPDM terpolymer.

Claims11

Dependent claims

A method of insulating a case of a rocket motor loaded with a solid propellant, comprising:

providing a kneader comprising at least one housing module provided with a chamber, a plurality of kneader pins extending radially into the chamber from the at least one housing module, and a screw which is rotatable about a longitudinal axis thereof and movable along the longitudinal axis in a reciprocating motion, the screw having a peripheral surface including a plurality of screw flights arranged to collectively define a discontinuous screw thread extending along the longitudinal axis of the screw;
preparing insulation from a composition comprising at least one cross-linkable polymer and carbon fibers by introducing the composition into the kneader and rotating the screw along the longitudinal axis thereof while superimposing the longitudinal reciprocating motion to the screw under substantially solvent-free conditions;
curing the composition to form the insulation;
and
insulating a case of a rocket motor with the insulation.

2 more elements

Dependencies are inferred from the claim text.

Method of insulating a case of a solid propellant rocket motor

Life of this patent

Method of insulating a case of a solid propellant rocket motor

Life of this patent

Abstract

Claims11