Polyamide aerogels
View Patent ↗A polyamide aerogel and method of making the same is disclosed. The aerogel includes para-substituted monomers without a cross-linking agent.
1. A method of creating a polyamide aerogel comprising:
preparing a solution including calcium chloride and a diamine in a first solvent;
cooling the solution to approximately 0° C.;
adding a solid diacid chloride to the solution;
allowing the solution to gel to form a gel;
soaking the gel in a second solvent to remove the first solvent and calcium chloride;
subjecting the gel to supercritical drying to remove the second solvent; and
drying the gel in a vacuum for a predetermined time period to form the polyamide aerogel, wherein the polyamide aerogel comprises a polymer backbone having a number of repeat units.
2. The method of claim 1 , wherein prior to allowing the solution to gel, the method further includes stirring the solution for a first time period until the solution becomes cloudy and the viscosity of the solution increases.
3. The method of claim 2 further comprising stirring the solution for a second time period.
4. The method of claim 3 further including pouring the solution into a mold and sealing the mold.
5. The method of claim 1 , wherein soaking the gel in a second solvent includes exchanging the second solvent a plurality of times during soaking.
6. The method of claim 1 , wherein the first solvent is N-methylpyrrolidinone.
7. The method of claim 1 , wherein the second solvent is selected from the group of ethanol and methanol.
8. The method of claim 1 , wherein the solid diacid chloride is at least one of terephthaloyl chloride and isophthaloyl dichloride and wherein the solution becomes transparent upon the adding of the solid diacid chloride.
9. The method of claim 1 , wherein the diamine is at least one of p-phenylene diamine, m-phenylene diamine, oxydianiline, dimethylbenzidine, and methylene dianiline.
10. The method of claim 1 , wherein the solid diacid chloride and the diamine are para-substituted monomers.
11. The method of claim 1 , wherein the number of repeat units is at least 20.
12. The method of claim 1 , wherein the number of repeat units is at most 60.