One part activator and blowing agent for foaming plastics

Claim 1

A method of making a stable one-part alkali metal borohydride concentrate comprising: (a) dry blending a mixture of an inert resinous polymer, an alkali metal borohydride, and a salt hydrate; (b) heating the mixture to a temperature above the melting point of the resin but a temperature less than that which would result in the release of a substantial amount of the water of hydration of the salt hydrate to form a molten mixture; (c) extruding the molten mixture and cooling to form a solid stable concentrate; and (d) forming the extruded and cooled concentrate into pellets.

Claim 2

A method of making a stable one-part alkali metal borohydride concentrate comprising: (a) dry blending a mixture of an inert resinous polymer, an alkali metal borohydride, and a salt hydrate; (b) heating the mixture to a temperature above the melting point of the resin but a temperature less than that which would result in the release of a substantial amount of the water of hydration of the salt hydrate to form a molten mixture; (c) extruding the molten mixture and cooling to form a solid stable concentrate; and (d) forming the extruded and cooled concentrate into pellets.

Claim 7

A method of making a stable one-part alkali metal borohydride activator system comprising: (a) dry blending a mixture of an inert resinous polymer and an alkali metal borohydride; (b) dry blending a mixture of an inert resinous polymer and a salt hydrate; (c) heating the mixture of (a) to a temperature above the melting point of the resin to form a molten mixture; (d) heating the mixture of (b) to a temperature above the melting point of the resin but a temperature less than that which would result in the release of a substantial amount of the water of hydration of the salt hydrate to form a molten mixture; (e) extruding the molten mixture of (c) to form a solid stable concentrate; (f) extruding the molten mixture of (d) to form a solid stable salt hydrate concentrate; (g) forming the extruded and cooled concentrate of (e) into pellets; (h) forming the extruded and cooled concentrate of (f) into pellets; (i) mixing the pellets of (g) with the pellets of (h) in an appropriate ratio.

Claim 8

A method of making a stable one-part alkali metal borohydride activator system comprising: (a) dry blending a mixture of an inert resinous polymer and an alkali metal borohydride; (b) dry blending a mixture of an inert resinous polymer and a salt hydrate; (c) heating the mixture of (a) to a temperature above the melting point of the resin to form a molten mixture; (d) heating the mixture of (b) to a temperature above the melting point of the resin but a temperature less than that which would result in the release of a substantial amount of the water of hydration of the salt hydrate to form a molten mixture; (e) extruding the molten mixture of (c) to form a solid stable concentrate; (f) extruding the molten mixture of (d) to form a solid stable salt hydrate concentrate; (g) forming the extruded and cooled concentrate of (e) into pellets; (h) forming the extruded and cooled concentrate of (f) into pellets; (i) mixing the pellets of (g) with the pellets of (h) in an appropriate ratio.