Granted Patent B2

US 7,691,325 · App. 11/551,090 · Granted Apr 6, 2010

Abstract

Claims (53)

1. A method of manufacturing a vapor-sensing device, comprising:

placing an aqueous dispersion of colloidal spheres on a substrate;

drying the aqueous dispersion of colloidal spheres to obtain a colloidal crystal;

filling the voids among the colloidal crystal with a crosslinked vapor-expandable matrix composition having a 2% to 5% crosslinking density;

curing the vapor-expandable matrix composition; and

peeling away any excess vapor-expandable matrix material from the surface of the film, wherein the colloidal crystal is exposed

wherein:

the vapor-expandable matrix comprises a composition that reversibly swells in the presence of at least one type of vapor, the composition selected from the group consisting of:

hydrogels, polydimethylsiloxane (PDMS), styrene-butadiene rubbers, nitrile rubbers, butyl rubbers, halogenated butyl rubbers, chloroprene rubbers, N-isopropyl acrylamides (NIPAMs), polyvinyl alcohols (PVAs), polyethylene oxides (PEOs), and polyethylene glycols (PEGs);

the colloidal crystal exhibits Bragg diffraction; and

at least one surface of the colloidal crystal is exposed directly to the environment.

2. The method according to claim 1 , wherein the vapor expandable matrix composition comprises polydimethylsiloxane (PDMS).

3. The method according to claim 1 , wherein the vapor expandable matrix composition comprises a hydrogel.

4. The method according to claim 1 , wherein the colloidal spheres comprises polystyrene.

5. The method according to claim 1 , wherein the colloidal spheres comprises silica.

6. The method according to claim 1 , wherein the colloidal spheres comprises titania.

7. The method according to claim 1 , wherein a diameter of the colloidal spheres is from about 150 nm to about 260 nm.

8. The method according to claim 1 , wherein the crosslinked vapor-expandable matrix composition has a crosslinking density of from about 2% to about 2.5%.

9. A vapor-sensing device, comprising:

a crosslinked vapor-expandable matrix having a 2% to 5% crosslinking density; and

a colloidal crystal comprising colloidal spheres embedded within the vapor-expandable matrix;

wherein:

the vapor-expandable matrix comprises a composition that reversibly swells in the presence of at least one type of vapor, the composition selected from the group consisting of:

hydrogels, polydimethylsiloxane (PDMS), styrene-butadiene rubbers, nitrile rubbers, butyl rubbers, halogenated butyl rubbers, chloroprene rubbers, N-isopropyl acrylamides (NIPAMs), polyvinyl alcohols (PVAs), polyethylene oxides (PEOs), and polyethylene glycols (PEGs);

the colloidal crystal exhibits Bragg diffraction; and

at least one surface of the colloidal crystal is exposed directly to the environment.

10. The device according to claim 9 , wherein an average diameter of the colloidal spheres is from about 150 nm to about 260 nm.

11. The device according to claim 9 , wherein the degree of crosslinking is from 2% to about 2.5%.

12. A method of detecting the presence of a vapor, comprising:

exposing the vapor-sensing device according to claim 9 , to the vapor, wherein the vapor swells the vapor-expandable matrix of the vapor-sensing device; and

observing a shift in a Bragg-diffraction peak of the vapor-sensing device.

13. The method according to claim 12 , wherein the step of observing a shift in a Bragg-diffraction peak of the vapor-sensing device includes quantifying a shift in a Bragg-diffraction peak to obtain a value, and correlating the value to a vapor concentration.

14. A vapor monitor badge, comprising:

a substrate;

a crosslinked vapor-expandable matrix having a 2% to 5% crosslinking density secured to the substrate; and

a colloidal crystal comprising colloidal spheres embedded within the vapor-expandable matrix;

wherein:

the vapor-expandable matrix comprises a composition that reversibly swells in the presence of at least one type of vapor, the composition selected from the group consisting of:

hydrogels, polydimethylsiloxane (PDMS), styrene-butadiene rubbers, nitrile rubbers, butyl rubbers, halogenated butyl rubbers, chloroprene rubbers, N-isopropyl acrylamides (NIPAMs), polyvinyl alcohols (PVAs), polyethylene oxides (PEOs), and polyethylene glycols (PEGs);

the colloidal crystal exhibits Bragg diffraction; and

at least one surface of the colloidal crystal is exposed directly to the environment.

15. The device according to claim 9 , wherein:

the vapor-expandable matrix comprises a composition that reversibly swells in the presence of volatile oil vapor, the composition selected from the group consisting of polydimethylsiloxane (PDMS), styrene-butadiene rubbers, nitrile rubbers, butyl rubbers, halogenated butyl rubbers, and chloroprene rubbers;

the colloidal spheres are composed of a material selected from the group consisting of polystyrene, polymethyl methacrylate (PMMA), glass beads, silica spheres, titania spheres, and zirconia spheres; and

the device is configured to exhibit a detectable shift in a Bragg diffraction peak in the presence of volatile oil vapor.

16. The device according to claim 9 , wherein:

the vapor-expandable matrix comprises a composition that reversibly swells in the presence of organic solvent vapor, the composition selected from the group consisting of polydimethylsiloxane (PDMS), styrene-butadiene rubbers, nitrile rubbers, butyl rubbers, halogenated butyl rubbers, and chloroprene rubbers;

the colloidal spheres are composed of a material selected from the group consisting of glass beads, silica spheres, titania spheres, and zirconia spheres; and

the device is configured to exhibit a detectable shift in a Bragg diffraction peak in the presence of organic solvent vapor.

17. The device according to claim 9 , wherein:

the vapor-expandable matrix comprises a composition that reversibly swells in the presence of water vapor, the composition selected from the group consisting of N-isopropyl acrylamides (NIPAMs), polyvinyl alcohols (PVAs), polyethylene oxides (PEOs), and polyethylene glycols (PEGs);

the colloidal spheres are composed of a material selected from the group consisting of polystyrene, polymethyl methacrylate (PMMA), glass beads, silica spheres, titania spheres, and zirconia spheres; and

the device is configured to exhibit a detectable shift in a Bragg diffraction peak in the presence of water vapor.

Assignments (10)