Porous resin structures
A method providing direct access to porous three-dimensionally (3D) continuous polymer network structures and shapes by combining BCP-resol co-assembly with CO 2 laser-induced transient heating. The CO 2 laser source transiently heats the BCP-directed resol hybrid films to high temperatures at the beam position, inducing locally controlled resol thermopolymerization and BCP decomposition in ambient conditions. This enables shaping of BCP-directed porous resin structures with tunable 3D interconnected pores in a single process. Pore size can be varied from 10 nm to about 600 nm.
1. A method of making a hierarchically porous structure comprising:
a) forming a layer comprising a first polymeric material and a second polymeric material on at least a portion of a surface of a substrate, wherein the first polymeric material self assembles providing structured domains, and
b) exposing at least a portion of the layer in air to electromagnetic radiation, wherein the first polymeric material, if present, and the second polymeric material are organic materials after the exposing,
wherein at least a portion of the first polymeric material in the portion of the layer exposed to the electromagnetic radiation decomposes forming the hierarchically porous structure.
2. The method of claim 1 , further comprising repeating b) a desired number of times.
3. The method of claim 2 , wherein the repeating b) is carried out by rastering a laser beam across the layer.
4. The method of claim 1 , wherein the electromagnetic radiation is provided by a laser.
5. The method of claim 4 , wherein the laser is a carbon dioxide (CO 2 ) laser.
6. The method of claim 1 , wherein the first polymeric material self assembles in step a) providing hierarchical structured domains.
7. The method of claim 1 , wherein pores having a pore size from 10 nm to 600 nm are formed.
8. The method of claim 1 , wherein the electromagnetic radiation induces selective thermal degradation of the first polymeric material.
9. The method of claim 1 , wherein only a portion of the layer is exposed to the electromagnetic radiation and the unexposed portion(s) of the layer are removed by contacting the layer with a solvent.
10. The method of claim 1 , wherein the second polymeric material is thermally polymerized.
11. The method of claim 1 , wherein the second polymeric material is a negative tone material.
12. The method of claim 1 , further comprising thermal treatment of the hierarchically porous structure to form a carbonized hierarchically porous structure.
13. The method of claim 1 , wherein the electromagnetic radiation does not carbonize the first polymeric material.
14. The method of claim 1 , the method further comprising using the layer as a template to form a layer comprising a silicon material.
15. The method of claim 1 , wherein the electromagnetic radiation does not carbonize the second polymeric material.
16. The method of claim 1 , wherein the electromagnetic radiation does not carbonize the first polymeric material or the second polymeric material.
17. The method of claim 1 , wherein the substrate is heated by the exposing.
18. A method of making a hierarchically porous structure comprising:
a) forming a layer comprising a first polymeric material and a second polymeric material on at least a portion of a surface of a substrate, wherein the first polymeric material self assembles providing structured domains, and
b) exposing at least a portion of the layer in air to electromagnetic radiation, wherein the substrate is heated, and the first polymeric material, if present, and the second polymeric material are organic materials after the exposing,
wherein at least a portion of the first polymeric material in the portion of the layer exposed to the electromagnetic radiation decomposes forming the hierarchically porous structure.