THIOL-ENE BASED POLY(ALKYLSILOXANE) MATERIALS

• US 20090096136A1
• Filed: 10/13/2008
• Published: 04/16/2009
• Est. Priority Date: 10/12/2007
• Status: Abandoned Application

• Current Assignee: Regents of the University of California (University of California)
• Original Assignee: Regents of the University of California (University of California)
• Inventors: Hawker, Craig J., Campos, Luis M., Meinel, Ines
• Application Number:
  US12/250,344
• Publication Number:
  US 20090096136A1
• Time in Patent Office: Days
• US Class Current: 264/483
• CPC Class Codes: C08F 2/48 by ultraviolet or visible light
• CPC Class Codes: C08G 75/045 from mercapto compounds and unsaturated compounds
• CPC Class Codes: C08G 75/12 Polythioether-ethers C08G75/0245 takes precedence
• CPC Class Codes: C08L 81/02 Polythioethers; Polythioether-ethers
• CPC Class Codes: C08L 83/08 containing silicon bound to organic groups containing atoms other than carbon, hydrogen and oxygen

Abstract

A stamp is comprised of a thiol-ene polymer, wherein the thiol-ene polymer allows for creation of micro-scale or nano-scale patterns useful in soft or imprint lithography. A patterned thiol-ene polymer is fabricated by casting a thiol-ene mixture onto a patterned mold, curing the thiol-ene mixture to form the patterned thiol-ene polymer, and peeling off the patterned thiol-ene polymer from the silicon mold. A stamp comprised of a thiol-ene polymer may be replicated by exposing the to oxygen plasma to form a hydrophilic mold, exposing the hydrophilic mold to a fluorinating agent under vacuum conditions to form a functionalized surface of the hydrophilic mold, casting a thiol-ene mixture on top of the functionalized surface, photocuring the thiolene mixture to form a replica thiol-ene polymer, and peeling off the replica thiol-ene polymer.

Claims

1. A thiol-ene polymer composition of matter, comprising:

a reaction mixture of one or more poly-thiol compounds blended with one or more alkene-functional monomers; and

a cross-linking between the alkene-functional monomers and the poly-thiol compounds that controls one or more physical properties of the thiol-ene polymer.

2. The composition of matter of claim 1, wherein the poly-thiol compounds comprise thiolpropyl substituted poly(mercaptopropylmethylsiloxane) (PMMS).

3. The composition of matter of claim 2, wherein the physical properties are a tunable Young'"'"'s modulus, hydro-phobicity or hydro-philicity.

4. The composition of matter of claim 1, wherein the alkene-functional monomers comprise one or more of the following:

ethylene glycol diacrylate (EGDA), 2,4,6-triallyloxy-1,3,5-triazine (TAOTA), and Ethoxylated (4) bisphenol A dimethacrylate (BPADMA).

5. The composition of matter of claim 1, wherein the physical properties are controlled by one or more of the following:

a composition of the alkene monomers, an alkene monomer to thiol weight to weight ratio (ene;

thiol ratio), a structure of the alkene monomers and physical properties of the alkene functional monomers.

6. The composition of matter of claim 1, wherein the physical properties enable the thiol-ene polymer to be molded into submicron and nano scale features with aspect ratios of up to 5 without collapse of the features.

7. The composition of matter of claim 1, wherein a first composition of one of the alkene monomers allows the thiol-ene polymer to withstand a stress greater than 1 MPa.

8. The composition of matter of claim 7, wherein a second composition of one of the alkene monomers allows the thiol-ene polymer to have a strain percentage (change in length divided by original length multiplied by 100) between 5% and 55%.

9. The composition of matter of claim 1, wherein a composition of the alkene monomers achieves a hydrophobicity for the thiol-ene compound.

10. The composition of matter of claim 1, wherein a composition of the alkene monomers allows the thiol-ene polymer to be cured at temperatures up to at least 225°

C.

11. The composition of matter of claim 1, wherein a composition of the alkene monomers renders the thiol-ene polymer transparent for wavelengths of light above 300 nm.

12. The composition of matter of claim 1, wherein a composition of a one of the alkene monomers renders the alkene monomers and the poly-thiol compound miscible.

13. The composition of matter of claim 1, wherein the alkene monomers comprise Ethoxylated (4) bisphenol A dimethacrylate (BPADMA) to increase a stress the thiolene polymer can withstand without breaking, as compared to without the BPADMA.

14. The composition of matter of claim 13, wherein the alkene monomers further comprise ethylene glycol diacrylate (EGDA) to increase a flexibility of the thiol-ene polymer as compared to without the EGDA.

15. The composition of matter of claim 13, wherein the alkene monomers further comprise 2,4,6-triallyloxy-1,3,5-triazine (TAOTA) to render the BPADMA and the poly thiol compound comprising PMMS miscible.

16. An apparatus for use in lithography, comprising:

a stamp comprised of a patterned thiol-ene polymer, wherein the patterned thiol-ene polymer allows for creation of micro-scale or nano-scale patterns useful in soft or imprint lithography.

17. The apparatus of claim 16, wherein the thiol-ene polymer is a thiol-ene based polyalkylsiloxane material.

18. The apparatus of claim 17, wherein the thiol-ene polymer comprises thiolpropyl substituted poly(mercaptopropylmethylsiloxane) (PMMS).

19. The apparatus of claim 16, wherein the thiol-ene polymer is made from a reaction mixture comprising poly-thiol compounds blended with alkene-functional monomers to produce the thiol-ene polymer, wherein the polymer achieves a cross linking that controls physical properties of the thiol-ene polymer.

20. A method for fabricating a thiol-ene polymer, comprising

(a) mixing one or more poly thiol compounds and one or more alkene-functional monomers in the presence of less than 0.1% of a radical photoinitiator;

and

(b) cross-linking the one or more thiol compounds and the one or more alkene-functional monomers, via radical addition to double bonds and radical-radical recombinations, thereby forming the thiol-ene polymer.

21. The method of claim 20, wherein the cross-linking is achieved through a photochemical process and in a presence of oxygen.

22. The method of claim 20, further comprising screening the alkene functional monomers to control physical properties of the thiol-ene polymer.

23. The method of claim 20, wherein the cross-linking is achieved thermally.

24. A method of fabricating a patterned thiol-ene polymer, comprising:

(a) casting a thiol-ene mixture onto a patterned mold;

(b) curing the thiol-ene mixture to form the patterned thiol-ene polymer; and

(c) peeling off the patterned thiol-ene polymer from the mold.

25. A method for replicating a stamp comprised of a thiol-ene polymer, comprising:

(a) exposing a stamp comprised of a thiol-ene polymer to oxygen plasma or ozonolysis to form a hydrophilic mold;

(b) exposing the hydrophilic mold to a fluorinating agent to form a functionalized surface of the hydrophilic mold;

(c) casting a thiol-ene mixture on top of the functionalized surface;

(d) photocuring the thiolene mixture to form a replica thiol-ene polymer; and

(e) peeling off the replica thiol-ene polymer from the functionalized surface of the hydrophilic mold.

26. The method of claim 25, wherein the functionalized surface is a hydrophobic surface.