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US 11,873,417 B2Granted
Scalable inter-diffused zwitterionic polyurethanes for durable antibacterial coatings
AssigneeUniversity of Houston System
InventorsHadi Ghasemi, Zixu Huang
Life of this patent
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Abstract
Durable antibacterial coatings are prepared by inter-diffusing zwitterionic polyurethane in acrylic polyurethane. Bacterial attachment is substantially eliminated from the surface of the coatings due to the hydrophilicity of the zwitterionic polyurethane. Long-term antibacterial properties were observed for both Gram-negative and Gram-positive bacteria even when the coatings were constantly challenged by mechanical abrasion.
Claims18
A method for preparing an antibacterial polyurethane coating, comprising:
- depositing an acrylic polyurethane base layer on a surface, wherein the acrylic polyurethane base layer is hydrophobic and comprises a ratio of hydroxyl groups to isocyanate groups of about 1.0/1.5;
- allowing the acrylic polyurethane base layer to partially cure, to produce a semi-cured acrylic polyurethane base layer;
- spraying a zwitterionic polyurethane on the semi-cured acrylic polyurethane base layer, wherein the zwitterionic polyurethane is hydrophilic and comprises a ratio of hydroxyl groups to isocyanate groups of about 1.1/1.0;
- allowing the zwitterionic polyurethane to inter-diffuse into the acrylic polyurethane base layer to form an inter-diffused polyurethane coating;
- and
- allowing the inter-diffused polyurethane coating to cure to form an antibacterial polyurethane coating, wherein the antibacterial polyurethane coating has a coating surface that is hydrophilic and lacks isocyanate groups.
3 more elements
A method for inhibiting bacterial attachment and biofilm formation on a surface, comprising:
- preparing an acrylic polyurethane base layer by blending acrylic polyol resin with an excess of hexamethylene diisocyanate cross-linker;
- depositing the acrylic polyurethane base layer on the surface, wherein the acrylic polyurethane base layer is hydrophobic and comprises a ratio of hydroxyl groups to isocyanate groups of about 1.0/1.5;
- allowing the acrylic polyurethane base layer to partially cure, to produce a semi-cured acrylic polyurethane base layer;
- spraying a zwitterionic polyurethane on the semi-cured acrylic polyurethane base layer, wherein the zwitterionic polyurethane is hydrophilic and comprises a ratio of hydroxyl groups to isocyanate groups of about 1.1/1.0, and wherein the zwitterionic polyurethane has a structure of:
- wherein n is between 2 and 70;
- allowing the zwitterionic polyurethane to inter-diffuse into the acrylic polyurethane base layer to form an inter-diffused polyurethane coating;
- and
- allowing the inter-diffused polyurethane coating to cure to form an antibacterial polyurethane coating, wherein the antibacterial polyurethane coating has a coating surface that is hydrophilic and lacks isocyanate groups, and wherein the antibacterial polyurethane coating inhibits bacterial attachment and biofilm formation on the coating surface.
5 more elements
Dependencies are inferred from the claim text.