Micro/nano-embossing process and useful applications thereof

• US 20030186405A1
• Filed: 04/01/2002
• Published: 10/02/2003
• Est. Priority Date: 04/01/2002
• Status: Abandoned Application

• Current Assignee: Ohio State University
• Original Assignee: The Ohio State University Research Foundation
• Inventors: Lai, Siyi, Lee, L. James
• Application Number:
  US10/113,233
• Publication Number:
  US 20030186405A1
• Time in Patent Office: Days
• US Class Current: 435/182
• CPC Class Codes: A61K 9/0097 Micromachined devices; Microelectromechanical systems [MEMS]; Devices obtained by lithographic treatment of silicon; Devices comprising chips intradermal microneedle arrays A61K9/0021; MEMS in general B81B7/02
• CPC Class Codes: B01D 2325/021 Pore shapes
• CPC Class Codes: B01D 2325/08 Patterned membranes
• CPC Class Codes: B01D 67/0025 by mechanical treatment, e.g. pore-stretching
• CPC Class Codes: B01D 69/02 characterised by their properties
• CPC Class Codes: B29C 2045/0094 injection moulding of small-sized articles, e.g. microarticles, ultra thin articles
• CPC Class Codes: B29C 33/3857 by making impressions of one or more parts of models, e.g. shaped articles and including possible subsequent assembly of the parts
• CPC Class Codes: B29C 45/02 Transfer moulding, i.e. transferring the required volume of moulding material by a plunger from a "shot" cavity into a mould cavity
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites

Abstract

The present invention relates to a method of producing micro and nano-porous polymeric articles with well-defined pore structures.

Claims

1. A polymeric plate containing a plurality of nano-tubes, said nano-tubes arranged in a predetermined manner.

2. The polymeric plate of claim 1, wherein at least one aperture of each of said nano-tubes has an effective diameter in the range from about 10 nanometers to about 100 nanometers.

3. The polymeric plate of claim 1, wherein said polymeric material is selected from the group consisting of photocurable and thermoplastic polymers.

4. The polymeric plate of claim 1 wherein said nano-tubes possess any geometry calculated to prevent substantially all material of a predetermined criterion to pass through said nano-tube while selectively allowing substantially all other material to pass, whereby said polymeric plate acts as a nanofilter.

5. The polymeric plate of claim 1 wherein said nano-tubes possess geometry selected from the group consisting of conical and pyramidal geometry.

6. A method of making a polymeric plate containing a plurality of nano-tubes comprising the steps:

obtaining a starting material arrangement comprising;

a support substrate;

a sacrificial layer supported by said substrate; and

a non-sacrificial layer on said sacrificial layer;

impressing an array of nano-members through said non-sacrificial layer and into said sacrificial layer; and

removing said sacrificial layer.

7. The method of claim 6 wherein said support substrate comprises a material selected from the group consisting of silicon, glass, teflon, and any other polymer capable of substantially maintaining dimensional stability upon increased heating.

8. The method of claim 6 wherein said sacrificial layer comprises a soluble polymer.

9. The method of claim 6 wherein said non-sacrificial layer in said starting material is in precursor form and wherein the method additionally comprises setting said precursor prior to removal of said sacrificial layer.

10. The method of claim 9 wherein said precursor form material is selected from the group consisting of thermoplastic solutions and spin-coated photocurable resins.

11. The method of claim 6 wherein said nano-member array comprises an arrangement of projections, said projections having effective diameters on either of their ends ranging from about 10 nanometers to about 100 nanometers.

12. The method of claim 6 wherein said nano-members possess any geometry calculated to prevent substantially all material of a predetermined criterion to pass through said nano-tube while selectively allowing substantially all other material to pass, whereby said polymeric plate acts as a nanofilter.

13. The method of claim 6 wherein said nano-members possess geometry selected from the group consisting of conical and pyramidal geometry.

14. The method according to claim 6 wherein said nano-member array is a material selected from the group consisting of a fiber optic bundle that has been differentially etched, silicon that has been anisotropically etched, and a polymer tip array that has been formed using a master plate containing nano-scale surface projections.

15. The method of claim 6 additionally comprising providing a patterned layer over said non-sacrificial layer so as to provide a material container in association with said non-sacrificial layer.

16. The method of claim 15 wherein the patterned layer is formed by photolithography.

17. A method of making a polymeric plate containing a plurality of nano-tubes comprising the steps:

obtaining a starting material arrangement of bulk material precursor;

impressing an array of nano-members into said bulk material precursor;

setting said bulk material precursor;

removing said array of nano-members; and

cleaving said bulk material precursor so as to expose a series of apertures.

18. The method of claim 17 wherein said bulk material precursor is selected from the group consisting of partially cured thermoset and heated thermoplastic polymers.

19. A polymeric container defining an inner volume wherein a portion of said container'"'"'s walls contain a plurality of nano-tubes, said nano-tubes arranged in a predetermined manner and positioned so as to place said inner volume in fluid contact with an outer environment.

20. The polymeric container of claim 19 wherein said inner volume is less than about 1 microliter.

21. The polymeric container of claim 19, wherein at least one aperture of each of said nano-tubes has an effective diameter in the range from about 10 nanometers to about 100 nanometers.

22. The polymeric container of claim 19 wherein said nano-tubes possess geometry selected from the group consisting of conical and pyramidal geometry.

23. A polymeric nano-filtering capsule comprising an inner volume enclosed by a polymeric surface, wherein a portion of said surface contains a plurality of nano-tubes, said inner volume in fluid contact with an environment outside said polymeric walls only through said nano-tubes.

24. The polymeric nano-filtering capsule of claim 23 wherein said inner volume is less than about 1 microliter.

25. A method of making a polymeric container defining an inner volume wherein a portion of said container'"'"'s walls contain a plurality of nano-tubes, said nano-tubes arranged in a predetermined manner and positioned so as to place said inner volume in fluid contact with an outer environment, said method comprising the steps:

obtaining a starting material arrangement comprising;

a container mold having a support structure, wherein said support structure corresponds to a portion of a container wherein a plurality of nano-tubes are to be prearranged;

a sacrificial layer supported by said support structure;

discharging a non-sacrificial material into said container mold, wherein said sacrificial material layer is covered;

impressing an array of nano-members through said non-sacrificial layer and into said sacrificial layer;

removing said sacrificial layer.

26. The method of claim 25 wherein said sacrificial layer comprises a soluble polymer.

27. The method of claim 25 wherein said non-sacrificial material is in precursor form and wherein the method additionally comprises setting said precursor prior to removal of said sacrificial layer.

28. The method of claim 27 wherein said precursor form material is selected from the group consisting of thermoplastic solutions and spin-coated photocurable resins.

29. The method of claim 25 wherein said nano-member array comprises an arrangement of projections, said projections having effective diameters on either of their ends ranging from about 10 nanometers to about 100 nanometers.

30. The method of claim 25 wherein said support structure corresponds to an inner volume of said container less than about 1 microliter.

31. The method of claim 25 wherein said nano-members possess geometry selected from the group consisting of conical and pyramidal geometry.

32. A method of making a polymeric nanofiltering capsule wherein an inner volume is enclosed by a polymeric surface and a portion of said surface contains a plurality of nano-tubes, said inner volume in fluid contact with an environment outside said polymeric walls only through said nano-tubes comprising the steps:

obtaining two polymeric containers whose surfaces each define an inner volume, at least one of which surfaces contains a plurality of nano-tubes arranged in a predetermined manner; and

bonding together said containers to form a capsule, wherein said capsule has an inner volume defined by a surface defined by the bonded constituent surfaces of said polymeric containers.

33. The method of claim 32 wherein said capsule inner volume is at least about 600 nanoliters.

34. A micro-transfer mold comprising:

a polymeric plate containing a plurality of nano-tubes, said nano-tubes arranged in a predetermined manner; and

a cavity plate containing a plurality of mold cavities arranged adjacent said non-sacrificial layer, wherein said mold cavities are dimensioned so as to form nanoparticles.

35. The micro-transfer mold of claim 34, additionally comprising a patterned layer arranged adjacent said polymeric plate to provide a material container, or transfer pot, in association with said polymeric plate, said patterned layer positioned on the side of said polymeric plate opposite said cavity plate.

36. The micro-transfer mold of claim 34 wherein the patterned layer is formed by photolithography.

37. A micro-transfer mold comprising:

a polymeric container defining an inner volume wherein a portion of said container'"'"'s walls contain a plurality of nano-tubes, said nano-tubes arranged in a predetermined manner and positioned so as to place said inner volume in fluid contact with an outer environment; and

a cavity plate containing a plurality of mold cavities arranged adjacent said non-sacrificial layer, wherein said mold cavities are dimensioned so as to form nanoparticles.

38. A method of micro-transfer molding comprising the steps:

obtaining a micro-transfer mold;

urging a moldable material through a plurality of nano-tubes in said micro-transfer mold and into mold cavities of said micro-tranfer mold; and

allowing said moldable material to set so as to form molded nanoparticles.

39. A method according to claim 38 comprising the additional step of packaging the cavity plate containing molded nanoparticles present in the mold cavities, said cavity plate becoming the carrier for said nanoparticles.

40. The nanoparticles produced by the method of claim 38

41. A method of micro-transfer molding comprising the steps:

obtaining a micro-transfer mold wherein a plurality of said micro-transfer mold'"'"'s mold cavities are partially filled with pre-deposited material;

urging a moldable material through a plurality of nano-tubes in said micro-transfer mold and into mold cavities of said micro-tranfer mold; and

allowing said moldable material to set so as to form molded nanoparticles that contain pre-deposited material.

42. A method according to claim 41 wherein said pre-deposited material comprises material selected from the group consisting of dry powder and granular materials.

43. The nanoparticles produced by the method of claim 41.

44. A method of micro-transfer molding comprising the steps:

obtaining a micro-transfer mold;

urging a moldable material through a plurality of nano-tubes in said micro-transfer mold and into mold cavities of said micro-tranfer mold such that the mold cavity is partially filled; and

repeatedly urging moldable material into said mold cavities as necessary so as to form layered molded nanoparticles.

45. A method according to claim 44 wherein the step of urging moldable material into said mold'"'"'s partially filled mold cavities utilizes moldable material different from the moldable material utilized in a prior iteration of urging moldable material into said mold cavities so that layered nanoparticles are formed, whereby the nanoparticle layers comprise differing moldable materials.

46. The nanoparticles produced by the method of claim 44.

47. The nanoparticles produced by the method of claim 45.