Method of hydrolytically stable bonding of elastomers to substrates

Patent metadata

Field	Value
Publication number	US-9422409-B2
Application number	US-200913123310-A
Country	US
Kind code	B2
Filing date	Oct 9, 2009
Priority date	Oct 10, 2008
Publication date	Aug 23, 2016
Grant date	Aug 23, 2016

Abstract

Active devices such as pumps and mixers have been fabricated in plastic-PDMS hybrid devices. By utilizing functionalized bis-silane primers, bond strength between Polycarbonate or PMMA and PDMS improved in dry and aqueous environments. Plastic-primer-PDMS layers exposed to acid and base solutions at 70° C. for 2 hours showed no signs of delamination at 30 psi for pH −1 to 15 and 60 psi for pH 0 to 15. A peristaltic pump fabricated in polycarbonate achieved consistent flow rates up to peristaltic cycle frequencies of 10 Hz in water, 1OM HCl, and 1OM NaOH solutions.

First claim

What is claimed is:

1. A method of bonding two surfaces said method comprising:
associating a molecule comprising at least two silane-derivative groups with a first surface;
contacting a second surface to said molecule;
wherein said first surface is a plastic material, and said second surface is an elastomer comprising Si, and wherein said second surface is a solid or cured surface;
wherein said molecule comprising at least two silane-derivative groups has formula (Y) m (Z) 3-m Si—X—Si(Y) m (Z) 3-m or formula (Y) m (Z) 3-m Si—X—R—X—Si(Y) m (Z) 3-m , wherein X is a C 1 -C 10 branched or unbranched alkyl chain, Y and Z are alkoxy groups, m is 1-3, and R is an organic reactive group, and
wherein at least one of Y and Z is a bulky alkoxy group.

2. A method of bonding two surfaces said method comprising:
a. associating a molecule comprising at least two silane-derivative groups with a first surface;
b. contacting a second surface to said molecule,
wherein said first surface is a plastic material, and said second surface is an elastomer comprising Si, and wherein said second surface is a solid or cured surface.

3. A method of bonding two surfaces said method comprising:
a. associating a molecule comprising at least two silane-derivative groups with a first surface;
b. contacting a second surface to said molecule;
wherein said first surface is a plastic material, and said second surface is an elastomer comprising Si,
wherein said molecule comprising at least two silane-derivative groups has formula (Y) m (Z) 3-m Si—X—Si(Y) m (Z) 3-m or formula (Y) m (Z) 3-m Si—X—R—X—Si(Y) m (Z) 3-m , wherein X is a C 1 -C 10 branched or unbranched alkyl chain, Y and Z are alkoxy groups, m is 1-3, and R is an organic reactive group, and
wherein at least one of Y and Z is a bulky alkoxy group of isopropoxy.

4. The method of claim 2 , wherein said plastic material comprises polycarbonate (PC), polymethylmethacrylate (PMMA) or polystyrene (PS).

5. The method of claim 2 , wherein before said associating step, a molecule comprising at least one silane-derivative group is applied to said first surface.

6. The method of claim 2 , wherein said associating step comprises evaporating said molecule onto said first surface.

7. The method of claim 2 , wherein said associating step comprises depositing said molecule from solution onto said first surface.

8. The method of claim 7 , wherein said at least two silane-derivative groups in said molecule are hydrolytically stable.

9. The method of claim 8 , wherein said deposition prevents hydrolytically unstable (e.g. Si—O—C) bonds from forming between said molecule comprising at least two silane derivative groups and said first surface.

10. The method of claim 7 , wherein said depositing from said solution comprises dip-coating or spin-coating said first surface by said solution, or spraying or wiping said first surface with said solution.

11. The method of claim 2 , wherein said associating step comprises depositing said molecule from a melt.

12. The method of claim 2 , wherein said molecule associated with said first surface form a 3D crosslinked structure on said first surface.

13. The method of claim 12 , wherein the thickness of said 3D crosslinked structure ranges between 50 nm and 200 nm.

14. The method of claim 2 , wherein after said contacting step, pressure is applied to at least a portion of said first surface, said second surface or a combination thereof.

15. The method of claim 2 , wherein before or after said associating step, said first surface, said second surface or a combination thereof are treated.

16. The method of claim 15 , wherein said treating step comprises plasma treatment.

17. The method of claim 15 , wherein said treating step comprises chemical treatment, a mechanical treatment or a combination thereof.

18. The method of claim 2 , wherein before and/or after said contacting step, an annealing or a baking or a curing step is performed.

19. The method of claim 18 , wherein said annealing or baking or curing step enhances the bonding between said first surface and said molecule, between said second surface and said molecule or a combination thereof.

20. The method of claim 18 , wherein said annealing or baking or curing step recovers hydrophobicity of said first surface, said second surface, said molecule or a combination thereof by removing hydrophilic end groups.

21. The method of claim 18 , wherein said annealing or said baking or said curing is conducted at a temperature ranging between 50° C. and 200° C.

22. The method of claim 18 , wherein said annealing or said baking or said curing is conducted at 70° C.

23. The method of claim 18 , wherein said annealing or said baking or said curing is conducted at 105° C.

24. The method of claim 18 , wherein said annealing or said baking or said curing is conducted for a period ranging from 20 h to 30 h.

25. The method of claim 18 , wherein said annealing or said baking or said curing is conducted for a period ranging from 0.5 h to 3 h.

26. The method of claim 18 , wherein said annealing is conducted under dry conditions.

27. The method of claim 2 , wherein said Si is in the form of a siloxane.

28. The method of claim 27 , wherein said siloxane comprises polydimethylsiloxane (PDMS).

29. The method of claim 28 , wherein the thickness of said PDMS ranges between 10 μm and 200 μm.

30. The method of claim 8 , wherein the thickness of said PDMS is approximately 70 μm.

31. The method of claim 2 , wherein said molecule comprising at least two silane-derivative groups is of the formula: (Y) m (Z) 3-m —Si—X—Si—(Y) m (Z) 3-m wherein X is a C 1 -C 10 branched or unbranched alkyl chain and Y and Z are alkoxy groups.

32. The method of claim 31 , wherein said Y is an ethoxy group and said Z is a methoxy group.

33. The method of claim 31 , wherein said molecule comprising at least two silane-derivative groups is bis(triethoxysilyl) ethane (BTESE).

34. The method of claim 2 , wherein said molecule comprising at least two silane-derivative groups is of the formula: (Y) m (Z) 3-m —Si—X—R—X—Si—(Y) m (Z) 3-m wherein X is a C 1 -C 10 branched or unbranched alkyl chain, Y and Z are alkoxy groups and R is an organic reactive group.

35. The method of claim 34 , wherein at least one of Y and Z is a bulky alkoxy group.

36. The method of claim 35 , wherein said bulky alkoxy groups are isopropanol groups.

37. The method of claim 35 , wherein said bulky alkoxy groups protect said silane-derivative groups from covalently bonding to said first surface, such that desired non-silaneous bond formation between said first surface and said molecule can be formed.

38. The method of claim 34 , wherein said Y is an isopropyl alkoxy group and said Z is a methoxy group.

39. The method of claim 34 , wherein said organic reactive group R comprises an amine, a hydroxy group, an ester group, a phosphate group, a sulfate group, a nitro group, a cyano group, a vinyl group, an acrylate group, a methacrylate group or a carboxylic acid group.

40. The method of claim 34 , wherein said organic reactive group R is covalently-bonded to said first surface.

4

Assignees

• Lee S Kevin
• Lee Harry
• Ram J Rajeev
• Massachusetts Inst Technology

Inventors

• Lee S Kevin
• Lee Harry
• Ram J Rajeev

Classifications

• B81B2201/058

  Microfluidics not provided for in B81B2201/051 - B81B2201/054 · CPC title

• C08J2369/00

  Characterised by the use of polycarbonates; Derivatives of polycarbonates · CPC title

• B29K2033/12

  Polymers of methacrylic acid esters, e.g. PMMA, i.e. polymethylmethacrylate · CPC title

• B29L2031/756

  Microarticles, nanoarticles · CPC title

• B29C65/8246

  Pressure tests, e.g. hydrostatic pressure tests · CPC title