Polyolefin-based aerogels
View Patent ↗The present invention relates to cross-linked polyolefin aerogels in simple and fiber-reinforced composite form. Of particular interest are polybutadiene aerogels. Especially aerogels derived from polybutadienes functionalized with anhydrides, amines, hydroxyls, thiols, epoxies, isocyanates or combinations thereof.
1. An aerogel material comprising a polybutadiene with cross-linkages, wherein the cross-linkages is a result of reactions between hydroxyl, amine, epoxy, anhydride, thiol or isocyanate groups in the polybutadiene and hydroxyl, amine, epoxy, anhydride, thiol or isocyanate groups of a hardner.
2. The material of claim 1 further comprising : B 4 C, Diatomite, Manganese ferrite, MnO, NiO, SnO, Ag 2 O, Bi 2 O 3 , TiC, WC, carbon black, titanium oxide, iron titanium oxide, zirconium silicate, zirconium oxide, iron (I) oxide, iron (III) oxide, manganese dioxide, iron titanium oxide (ilmenite), chromium oxide, silicon carbide or mixtures thereof.
3. The material of claim 1 further comprising fibers in the form of chopped fibers, a batting, a mat, a felt or a combination thereof.
4. The material of claim 1 wherein the thermal conductivity at temperatures of about 30° C. and atmospheric pressures is about 50 mW/mK or less.
5. The material of claim 1 wherein the density is between about 0.03 and about 0.3 g/cm 3 .
6. An aerogel material comprising a polybutadiene with cross-linkages, wherein the cross linkages between polybutadiene chains comprises an amic acid, amide, imide, ester, urea, carbamate or a combination thereof.
7. A method of preparing an aerogel material comprising the steps of:
dissolving an amount of a polybutadiene in a suitable solvent;
adding an amount of hardner to the polybutadiene solution;
adding a catalyst suitable for cross linking, to the solution;
allowing the solution to form a gel; and
drying said gel, wherein the polybutadiene comprises hydroxyl, epoxy, anhydride, thiol, isocyanate functional groups or a combination thereof.
8. The method of claim 7 wherein the gel is dried above the critical point of the solvent.
9. The method of claim 7 wherein the gel is dried in supercritical carbon dioxide.
10. The method of claim 7 further comprising a step of aging said gel before the drying thereof.
11. A product made by the method of claim 7 .
12. A method of preparing an aerogel material comprising the steps of:
dissolving an amount of a polybutadiene in a suitable solvent;
adding an amount of hardner to the polybutadiene solution;
adding a catalyst suitable for cross linking, to the solution;
allowing the solution to form a gel; and
drying said gel, wherein the hardner comprises hydroxyl, epoxy, anhydride, thiol, isocyanate functional groups or a combination thereof.
13. A method of preparing an aerogel material comprising the steps of:
dissolving an amount of a polybutadiene in a suitable solvent;
adding an amount of hardner to the polybutadiene solution;
adding a catalyst suitable for cross linking, to the solution;
allowing the solution to form a gel; and
drying said gel, wherein the polybutadiene comprises anhydride functionalized polybutadiene.