Processes for making shaped honeycomb and honeycombs made thereby

1. A process of making a honeycomb comprising cells having edges forming a face of the honeycomb, the face defined by a plurality of points, at least two of the points located in different tangential planes, comprising the steps of:

a) forming a honeycomb having expanded cells from a plurality of sheets comprising thermoplastic material having a melting point of from 120 to 350° C. and high modulus fiber having a modulus of 600 grams per denier (550 grams per dtex) or greater;

b) impregnating the honeycomb with a thermoset resin which requires curing;

c) curing or partially curing the thermoset resin of b) to form a cured or partially cured honeycomb;

d) pressing the cured or partially cured honeycomb in a direction perpendicular to a plane of parallel lines of adhesive to fracture at least a portion of the thermoset resin;

e) pulling the pressed honeycomb apart in a direction perpendicular to a plane of parallel lines of adhesive to fracture at least a portion of the cured or partially cured thermoset resin to collapse at least a portion of cells of the honeycomb;

f) bending, molding, or forming the honeycomb in a mold or over a form;

g) heating the honeycomb to allow the thermoplastic material to flow; and

h) cooling the honeycomb to substantially retain the shape of the mold or form.

2. The process of making a honeycomb of claim 1 wherein the high modulus fiber is present in an amount of from about 50 to 95 parts by weight and the thermoplastic material is present in an amount of from 5 to 50 parts by weight.

3. The process of making a honeycomb of claim 2 wherein the high modulus fiber is present in an amount of from about 60 to 80 parts by weight.

4. The process of making a honeycomb of claim 2 wherein the thermoplastic material is present in an amount of from 20 to 40 parts by weight.

5. The process of making a honeycomb of claim 1 wherein the high modulus fiber comprises para-aramid polymer.

6. The process of making a honeycomb of claim 5 wherein the para-aramid polymer is poly (paraphenylene terephthalamide).

7. The process of making a honeycomb of claim 1 wherein the high modulus fiber is selected from the group consisting of carbon fiber, polybenzazole fiber, polypyridazole fiber, and mixtures thereof.

8. The process of making a honeycomb of claim 1 wherein the thermoplastic material comprises polyester polymer.

9. The process of making a honeycomb of claim 8 wherein the polyester polymer is a liquid crystalline polymer.

10. The process of making a honeycomb of claim 1 wherein the thermoplastic material is selected from the group consisting of polyolefin, polyamide, polyetherketone, polyetheretherketone, polyamide-imide, polyether-imide, polyphenylene sulfide, and mixtures thereof.

11. The process of making a honeycomb of claim 1 wherein the pressing of step d) is accomplished while also laterally supporting or restraining the faces of the honeycomb.

12. A honeycomb made by the process of claim 1 wherein after the cooling step less than 25 percent of the honeycomb cells have a re-entrant angle of greater than 180 degrees.