Biopolymer-based electromagnetic interference shielding materials
An electromagnetic interference (EMI) shielded device which includes an object to be shielded and an EMI shielding material encompassing the object. The EMI shielding material is made up of, but not limited to a broadband biopolymer or polymer dissolved in organic solvents, and metal and carbon-based nano-powders or nanoparticles. The specific makeup of the shielding material and fabrication procedure of the shielding material is also included herein.
1. A method of making an EMI shielding material, the method comprising:
dissolving DNA in a first amount of de-ionized water for a first period of time to form a DNA solution;
dissolving CTMA in a second amount de-ionized water for a second period of time to form a CTMA solution;
making a DNA-CTMA complex by adding the DNA solution to the CTMA solution, thereby causing a DNA-CTMA precipitate to form;
making an alcohol based DNA-CTMA solution by dissolving the DNA-CTMA precipitate in alcohol; and
making the EMI shielding material by mixing nano-powders or nanoparticles, the nano-powders or nanoparticles being one of metal or semiconductor nano-powders or nanoparticles, with the alcohol based DNA-CTMA solution.
2. The method of claim 1 , wherein a temperature of the first and second amounts of de-inonized water is about 60° F. to about 80° F.
3. The method of claim 1 , wherein a ratio of DNA to de-ionized water is about 4 grams/liter.
4. The method of claim 1 , wherein the first period of time is about two hours.
5. The method of claim 1 , wherein a ratio of CTMA to de-ionized water is about 4 grams/liter.
6. The method of claim 1 , wherein the second period of time is about five minutes.
7. The method of claim 1 , wherein adding the DNA solution to the CTMA solution comprises adding the DNA solution drop-wise to the CTMA solution.
8. The method of claim 7 , wherein a rate of adding the DNA solution drop-wise to the CTMA solution is about 1 drop per minute.
9. The method of claim 1 , wherein the nano-powders or nanoparticles are neutral in charge.
10. The method of claim 1 , wherein the nano-powders or nanoparticles are metal or carbon based nano-powders or nanoparticles-.
11. A method for scattering an EMI signal, the method comprising:
using the EMI shielding material made by the method of claim 1 .
12. A method for shielding of electromagnetic radiation and radar stealth, the method comprising:
using the EMI shielding material made by the method of claim 1 .
13. The method of claim 1 , wherein the nano-powders or nanoparticles are positively charged.
14. The method of claim 1 , wherein the nano-powders or nanoparticles are negatively charged.
15. A method of making an EMI shielding material, the method comprising:
dissolving DNA in a first amount of de-ionized water for a first period of time to form a DNA solution;
mixing positively charged nano-powders or nanoparticles, the nano-powders or nanoparticles being one of metal or semiconductor nano-powders or nanoparticles, to the DNA solution, in order to make a DNA-nano-powder or nanaprticle solution;
dissolving CTMA in a second amount de-ionized water for a second period of time to form a CTMA solution;
making a DNA-CTMA-metal or semiconductor nanopowder or nanoparticle complex by adding the DNA-nano-powder or nanaprticle solution to the CTMA solution, thereby causing a DNA-CTMA-nano-powder or nanparticle precipitate to form;
making an alcohol based DNA-CTMA-nanopowder or nanoparticle EMI shielding material solution by dissolving the DNA-CTMA-nanopowder or nanoparticle precipitate in alcohol.
16. The method of claim 15 , wherein a temperature of the first and second amounts of de-inonized water is about 60° F. to about 80° F.
17. The method of claim 15 , wherein a ratio of DNA to de-ionized water is about 4 grams/liter.
18. The method of claim 15 , wherein the first period of time is about two hours.
19. The method of claim 15 , wherein a ratio of CTMA to de-ionized water is about 4 grams/liter.
20. The method of claim 15 , wherein the second period of time is about five minutes.
21. The method of claim 15 , wherein adding the DNA-nano-powder or nanaprticle solution to the CTMA solution comprises adding the DNA solution drop-wise to the CTMA solution.
22. The method of claim 21 , wherein a rate of adding the DNA-nano-powder or nanaprticle solution drop-wise to the CTMA solution is about 1 drop per minute.
23. The method of claim 15 , wherein the nano-powders or nanoparticles are metal or carbon based nano-powders or nanoparticles.
24. A method of making an EMI shielding material, the method comprising:
dissolving DNA in a first amount of de-ionized water for a first period of time to form a DNA solution;
dissolving CTMA in a second amount de-ionized water for a second period of time to form a CTMA solution;
mixing negatively charged nano-powders or nanoparticles, the nano-powders or nanoparticles being one of metal or semiconductor nano-powders or nanoparticles, to the CTMA solution, in order to make a CTMA-nano-powder or nanaprticle solution;
making a DNA-CTMA-nano-powder or nanoparticle complex by adding the DNA solution to CTMA-nano-powder or nanaprticle solution, thereby causing a DNA-CTMA-nano-powder or nanparticle precipitate to form;
making an alcohol based DNA-CTMA-nano-powder or nanoparticle EMI shielding material solution by dissolving the DNA-CTMA-nano-powder or nanoparticle precipitate in alcohol.
25. The method of claim 24 , wherein a temperature of the first and second amounts of de-inonized water is about 60° F. to about 80° F.
26. The method of claim 24 , wherein a ratio of DNA to de-ionized water is about 4 grams/liter.
27. The method of claim 24 , wherein the first period of time is about two hours.
28. The method of claim 24 , wherein a ratio of CTMA to de-ionized water is about 4 grams/liter.
29. The method of claim 24 , wherein the second period of time is about five minutes.
30. The method of claim 24 , wherein adding the DNA solution to the CTMA-nano-powder or nanaprticle solution comprises adding the DNA solution drop-wise to the CTMA solution.
31. The method of claim 30 , wherein a rate of adding the DNA solution drop-wise to the CTMA-nano-powder or nanaprticle solution is about 1 drop per minute.
32. The method of claim 24 , wherein the nano-powders or nanoparticles are metal or carbon based nano-powders or nanoparticles.