Foams containing functionalized metal oxide nanoparticles and methods of making same

• US 6,353,037 B1
• Filed: 07/12/2000
• Issued: 03/05/2002
• Est. Priority Date: 07/12/2000
• Status: Expired due to Term

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Hanggi, Douglas Alan, Thunhorst, Kristin LaVelle
• Primary Examiner(s): Foelak, Morton
• Application Number:
  US09/614,574
• Time in Patent Office: 601 Days
• Field of Search: 521/64, 521/15.3, 522/81, 522/83, 522/84
• US Class Current: 521/64
• CPC Class Codes: C08J 9/283 a discontinuous liquid phase emulsified in a continuous macromolecular phase

Abstract

The invention discloses methods for making foams comprising functionalized metal oxide nanoparticles by photopolymerizing or thermally polymerizing emulsions comprising a reactive phase and a phase immiscible with the reactive phase components. Foams made from water-in-oil emulsions, including high internal phase emulsion are also disclosed. Articles and uses for the foams are also described.

Claims

1. A process for making a crosslinked polymeric foam comprising:

a) mixing a reactive phase comprising at least one polymerizable material and at least one functionalized metal oxide nanoparticle material with at least one initiator and a fluid immiscible with the reactive phase to form an emulsion wherein the immiscible fluid forms a discontinuous or co-continuous phase with the continuous reactive phase;

b) shaping the emulsion; and

c) exposing the emulsion to radiation suitable to activate the included initiator to form a crosslinked polymeric foam.

2. The process of claim 1 wherein the reactive phase further contains a crosslinking agent.

3. The process of claim 1 wherein the reactive phase further contains an emulsifier.

4. The process of claim 1 wherein the polymerizable material comprises an ethylenically-unsaturated monomer.

5. The process of claim 1 wherein the polymerizable material acts as a crosslinking agent.

6. The process of claim 1 wherein at least one polymerizable material also acts as an emulsifier.

7. The process of claim 1 wherein at least one functionalized metal oxide nanoparticle material also acts as an emulsifier.

8. The process of claim 1 wherein the immiscible fluid is water.

9. The process of claim 1 wherein the immiscible fluid comprises at least 74 volume percent of the emulsion.

10. The process of claim 1 wherein the emulsion is applied onto or into materials before polymerization and crosslinking.

11. The process of claim 1 wherein at least one functionalized metal oxide nanoparticle material is in the reactive phase.

12. The process of claim 1 wherein the reactive phase further comprises materials that can incorporate post reactive functional groups into the foam.

13. The process of claim 1 wherein the emulsion is one or both of polymerized and crosslinked using at least ultraviolet or visible radiation of 200 to 800 nanometers.

14. The process of claim 1 wherein the emulsion is one or both of polymerized and crosslinked using at least thermal energy.

15. A process for making a crosslinked polymeric foam comprising:

a) mixing reactive phase comprising at least one polymerizable material with at least one initiator and a fluid immiscible with the reactive phase, said immiscible fluid comprising at least one functionalized metal oxide nanoparticle material, to form an emulsion wherein the immiscible fluid forms a discontinuous or co-continuous phase with the continuous reactive phase;

b) shaping the emulsion; and

c) exposing the emulsion to radiation suitable to activate the included initiator to form a crosslinked polymeric foam.