Carbide and nitride ternary ceramic glove and condom formers
A slip-cast article former containing ternary ceramics, particularly of carbide and nitride materials, having the formula M n+1 AX n (MAX), where M is a transition metal, A is an element from Groups IA and IVA of the periodic table, X is nitrogen or carbon and n is 1, 2, or 3. The ternary ceramic article may be a glove or condom former. A process for making a ternary ceramic article employing a slip cast method.
1. A hollow slip-cast article comprising:
a ternary ceramic material having chemical formula of M n+1 AX n , where M is a transition metal, where A is an element selected from the group consisting of Group IIIA elements, Group IVA elements, S, P, As, and Cd, where X is selected from the group consisting of carbon, nitrogen, and combinations thereof, and where n is selected from the group consisting of 1, 2, and 3.
2. The article of claim 1 , wherein the transition metal is selected from the group consisting of Ti, Nb, Zr, Hf, Cr, Ta, V, Mo, and Sc.
3. The article of claim 1 , wherein A is selected from the group consisting of Al, Ge, Sn, Pb, Ga, Tl, P, S, As, Cd, and In.
4. The article of claim 1 wherein the hollow slip cast article is in the shape of a hollow condom or glove former and being substantially resistant to pitting.
5. The article of claim 4 wherein the article is resistant to pitting after approximately two weeks of exposure to a 20% solution of potassium hydroxide at 170° F.
6. A method for forming a slip-cast article comprising:
preparing an aqueous dispersion of a ternary ceramic material having chemical formula of M n+1 AX n , where M is a transition metal, where A is an element selected from the group consisting of Group IIIA elements, Group IVA elements, S, P, As, and Cd, where X is selected from the group consisting of carbon, nitrogen, and combinations thereof, and where n is selected from the group consisting of 1, 2, and 3;
introducing a quantity of the aqueous dispersion into a mold, the mold having a cavity therein with an interior surface defining a preselected hollow shape, to substantially fill the cavity;
allowing a layer of the ternary ceramic material to develop on the interior surface of the cavity;
removing an excess of aqueous dispersion from the cavity;
forming the slip-cast article from the layer of ternary ceramic material;
separating the mold and the slip-cast article;
drying the slip-cast article; and
sintering the slip-cast article.
7. The method of claim 6 comprising forming the slip-case article in the shape of a hollow condom or glove former wherein the article is substantially resistant to pitting.
8. The method of claim 7 wherein the article is resistant to pitting after approximately two weeks of exposure to a 20% solution of potassium hydroxide at 170° F.
9. The method of claim 6 wherein the preparing step further comprises selecting Ti 3 SiC 2 as the ternary ceramic material.
10. The method of claim 6 , wherein the transition metal is selected from the group consisting of Ti, Nb, Zr, Hf, Cr, Ta, V, Mo, and Sc.
11. The method of claim 6 , wherein A is selected from the group consisting of Al, Ge, Sn, Pb, Ga, Tl, P, S, As, Cd, and In.
12. The method of claim 6 wherein the preparing step further comprises blending (w/w) between about 15 to about 83% of the ternary ceramic material, between about 1 to about 20% of a binder, and about 1 to about 5% of a viscosity modifier to form the aqueous dispersion.
13. The method of claim 12 wherein the preparing step further comprises selecting a binder from the group consisting of cellulose powder, derivatives of cellulose, and combinations thereof.
14. The method of claim 12 wherein the preparing step further comprises selecting a viscosity modifier from the group consisting of carboxymethylcellulose, polyacrylate acid polymer, and combinations thereof.
15. The method of claim 12 wherein the preparing step further comprises preparing an aqueous dispersion having a solids content from about 25 to about 85% solids.
16. The method of claim 15 wherein the preparing step further comprises preparing an aqueous dispersion having a solids content from about 80 to about 85% solids.
17. The method of claim 6 wherein the mold is formed from plaster of Paris.
18. The method of claim 6 wherein the step of drying further comprises air drying the article for from about ½ to about 5 hours.
19. The method of claim 6 wherein the step of sintering the ternary ceramic material further comprises firing the article in an oven for from about 1 hour to about 8 hours at a temperature from about 1,000 to about 1,500° C.
20. A condom or glove former made by the method of claim 6 .
21. A condom or glove former made by the method of claim 8 .