Antimicrobial substrate

• US 8,685,424 B2
• Filed: 10/13/2011
• Issued: 04/01/2014
• Est. Priority Date: 10/14/2010
• Status: Active Grant

• Current Assignee: Zeus Co. LLC
• Original Assignee: Zeus Industrial Products, Inc.
• Inventors: Ballard, Robert L., Anneaux, Bruce L., Manasco, Joshua L.
• Primary Examiner(s): Krass, Frederick
• Assistant Examiner(s): Cohen, Michael P
• Application Number:
  US13/272,412
• Publication Number:
  US 20120114722A1
• Time in Patent Office: 901 Days
• Field of Search: None
• US Class Current: 424/409
• CPC Class Codes: A01N 25/10 Macromolecular compounds
• CPC Class Codes: A01N 59/02 Sulfur; Selenium; Tellurium; Compounds thereof
• CPC Class Codes: A01N 59/16 Heavy metals; Compounds thereof
• CPC Class Codes: B29C 48/05 Filamentary, e.g. strands
• CPC Class Codes: B29C 48/9165 Electrostatic pinning
• CPC Class Codes: D01D 5/0007 Electro-spinning non-woven fabrics produced by electro-spinning D04H1/728
• CPC Class Codes: D01F 1/103 Agents inhibiting growth of microorganisms
• CPC Class Codes: D01F 6/12 from polymers of fluorinated hydrocarbons
• CPC Class Codes: D01F 6/48 of polymers of halogenated hydrocarbons
• CPC Class Codes: D04H 1/4318 Fluorine series
• CPC Class Codes: D04H 1/728 by electro-spinning electro-spinning methods and apparatus D01D5/0007

Abstract

A method of preparing antimicrobial-containing polymeric products is provided, the method involving electrospinning a dispersion comprising a dispersible polymer, a fiberizing polymer, and one or more antimicrobial agents. The electrospun material is heated to remove solvent and the fiberizing polymer, giving a nonwoven polymeric material having antimicrobial agent incorporated therein. The material can be in the form of, for example, a non-woven sheet, tube, or covering.

Claims

1. A method of making a nonwoven mat comprising one or more antimicrobial agents, comprising:

providing a dispersion comprising;

a fluorinated polymer;

a fiberizing polymer;

one or more antimicrobial agents; and

a solvent;

electrospinning said dispersion to give a mat precursor; and

heating said mat precursor at a temperature and for a time sufficient to remove said solvent and said fiberizing polymer, in order to form a nonwoven mat.

2. The method of claim 1, wherein said electrospinning comprises:

providing an apparatus comprising a charge source and a target a distance from said charge source;

providing a voltage source to create a first charge at said charge source and an opposing charge at said target wherein said dispersion is electrostatically charged by contact with said charge source; and

collecting said electrostatically charged dispersion on said target.

3. The method of claim 1, wherein the one or more antimicrobial agents are selected from the group consisting of silver, silver compounds, metal oxides, metal sulfides, and mixtures thereof.

4. The method of claim 3, wherein the one or more antimicrobial agents comprise silver nanoparticles.

5. The method of claim 3, wherein the metal oxides and metal sulfides are selected from the group consisting of titanium dioxide, selenium sulfide, cadmium oxide, zinc oxide, and mixtures thereof.

6. The method of claim 1, wherein said nonwoven mat comprises the one or more antimicrobial agents in an amount of between about 10 ppm and about 10,000 ppm.

7. The method of claim 6, wherein said nonwoven mat comprises the one or more antimicrobial agents in an amount of between about 1,000 ppm and about 5,000 ppm.

8. The method of claim 1, wherein said fluorinated polymer is provided in the form of a resin comprising about 50% to about 80% polymer solids by weight.

9. The method of claim 1, wherein said fluorinated polymer has an average particle size of between about 0.1 μ

m and about 0.3 μ

m.

10. The method of claim 1, wherein said fluorinated polymer comprises polytetrafluoroethylene.

11. The method of claim 1, wherein said fluorinated polymer is selected from the group consisting of fluorinated ethylene propylene (FEP), polyvinylidene fluoride (PVDF), perfluoroalkoxy (PFA), a copolymer of tetrafluoroethylene, hexafluoropropylene and vinylidene fluoride (THV), poly(ethylene-co-tetrafluoroethylene) (ETFE), ethylene chlorotrifluoroethylene (ECTFE), PCTFE (polychlorotrifluoroethylene), and copolymers, blends, and derivatives thereof.

12. The method of claim 1, wherein the amount of fiberizing polymer is between about 3.0 and about 5.5 percent by weight of the amount of fluorinated polymer.

13. The method of claim 1, wherein said fiberizing polymer has a solubility in said solvent of greater than about 0.5 weight percent at room temperature.

14. The method of claim 1, wherein said fiberizing polymer is polyethylene oxide.

15. The method of claim 14, wherein the polyethylene oxide has a number average molecular weight of from about 50,000 amu to about 4,000,000 amu.

16. The method of claim 1, wherein said solvent is water.

17. The method of claim 1, wherein said dispersion has a viscosity of greater than 50,000 cP.

18. The method of claim 17, wherein the viscosity is from about 70,000 cP to about 150,000 cP.

19. The method of claim 1, wherein the voltage used during electrospinning is about 2,000 to about 100,000 volts.

20. The method of claim 1, wherein the heating is conducted between about 350°

C. and about 485°

C.

21. A method of making a nonwoven polytetrafluoroethylene mat comprising one or more antimicrobial agents, comprising:

providing a dispersion comprising;

polytetrafluoroethylene;

polyethylene oxide;

one or more antimicrobial agents selected from the group consisting of silver, silver compounds, metal oxides, metal sulfides, and mixtures thereof; and

a solvent;

electrospinning said dispersion to give a polytetrafluoroethylene mat precursor; and

heating said polytetrafluoroethylene mat precursor at a temperature and for a time sufficient to remove said solvent and polyethylene oxide, in order to form a nonwoven polytetrafluoroethylene mat.