Antimicrobial coatings comprising organosilane homopolymers
Aqueous antimicrobial coating compositions are disclosed comprising at least one organosilane homopolymer, present as a distribution of polymer chain lengths, and optionally at least one amine. A method of preparing an antimicrobial coating comprises coating a surface with the aqueous antimicrobial coating composition and allowing the composition to dry into a film that exhibits residual antimicrobial efficacy against microorganisms even after mechanical abrasion of the coating. The organosilane homopolymer may comprise only 3-aminopropylsilanetriol homopolymer, mixtures of 3-aminopropylsilanetriol homopolymer, 3-chloropropylsilanetriol homopolymer and 3-(trihydroxysilyl)propyl dimethyloctadecyl ammonium chloride homopolymer, or any one of various unique organosilane homopolymers having multiple amine functionality.
1. An aqueous antimicrobial coating composition comprising:
an organosilane homopolymer having the polymeric structure:
wherein n≥2;
an organosilane homopolymer having the polymeric structure:
wherein n≥2;
an organosilane homopolymer having the polymeric structure:
wherein n≥2; and
triethanolamine.
2. The aqueous antimicrobial coating composition of claim 1 , wherein the organosilane homopolymers are present in the aqueous antimicrobial coating in total at from about 0.01 wt. % to about 15 wt. %, based on the total weight of the composition.
3. The aqueous antimicrobial coating composition of claim 1 , further comprising from about 0.01 wt. % to about 5.0 wt. % of at least one amine, based on the total weight of the composition, wherein the at least one amine has the structure R 9 R 10 R 11 N, wherein R 9 , R 10 , and R 11 are independently H, alkyl, substituted alkyl, aryl, substituted aryl or cyclic, having a molecular weight of less than about 200 g/mole and a pKa of from about 7 to about 12.
4. The aqueous antimicrobial coating composition of claim 1 , wherein triethanolamine is present in the aqueous antimicrobial coating composition at from about 0.01 wt. % to about 1.0 wt. %, based on the total weight of the composition.
5. The aqueous antimicrobial coating composition of claim 1 , wherein the only organosilane homopolymers present in the aqueous antimicrobial coating composition are 3-aminopropylsilanetriol homopolymer, having a chain length distribution of n=2 to about 30; 3-chloropropylsilanetriol homopolymer, having a chain length distribution of n≥2; and 3-(trihydroxysilyl)propyl dimethyloctadecyl ammonium chloride homopolymer having a chain length distribution of n≥2.
6. The aqueous antimicrobial coating composition of claim 1 , wherein the triethanolamine is present at from about 0.01 wt. % to about 5.0 wt. %, based on the total weight of the composition.
7. A method of preparing an antimicrobial coating on a surface, the method comprising:
(a) disposing on the surface an aqueous antimicrobial coating composition comprising:
an organosilane homopolymer having the polymeric structure:
wherein n≥2;
an organosilane homopolymer having the polymeric structure:
wherein n≥2;
an organosilane homopolymer having the polymeric structure:
wherein n≥2; and
triethanolamine;
and
(b) allowing the aqueous antimicrobial coating composition thus disposed on the surface to dry.
8. The method of claim 7 , wherein the aqueous antimicrobial coating composition further comprises from about 0.01 wt. % to about 5.0 wt. % of at least one amine, based on the total weight of the aqueous antimicrobial coating composition, wherein the at least one amine has the structure R 9 R 10 R 11 N, wherein R 9 , R 10 , and R 11 are independently H, alkyl, substituted alkyl, aryl, substituted aryl or cyclic, having a molecular weight of less than about 200 g/mole and a pKa of from about 7 to about 12.
9. The method of claim 7 , wherein triethanolamine is present in the aqueous antimicrobial coating composition at from about 0.01 wt. % to about 1.0 wt. %, based on the total weight of the aqueous antimicrobial coating composition.
10. The method of claim 7 , wherein the only organosilane homopolymers present in the aqueous antimicrobial coating composition are 3-aminopropylsilanetriol homopolymer, having a chain length distribution of n=2 to about 30; 3-chloropropylsilanetriol homopolymer, having a chain length distribution of n≥2; and 3-(trihydroxysilyl)propyl dimethyloctadecyl ammonium chloride homopolymer having a chain length distribution of n≥2.
11. The method of claim 7 , wherein the aqueous antimicrobial coating composition comprises from about 0.01 wt. % to about 5.0 wt. % of triethanolamine, based on the total weight of the composition.
12. The aqueous antimicrobial coating composition of claim 1 consisting essentially of:
a total of from about 0.01 wt. % to about 15 wt. % of a mixture of 3-aminopropylsilanetriol homopolymer having a chain length distribution of n=3 to about 30, 3-chloropropylsilanetriol homopolymer having a chain length distribution of n≥2, 3-(trihydroxysilyl)propyl dimethyloctadecyl ammonium chloride homopolymer having a chain length distribution of n≥2;
from about 0.01 wt. % to about 5.0 wt. % triethanolamine; and
water.
13. The method of claim 7 , wherein the organosilane homopolymers are present in the aqueous antimicrobial coating in total at from about 0.01 wt. % to about 15 wt. %, based on the total weight of the composition.
14. The method of claim 7 , wherein the aqueous antimicrobial coating composition consists essentially of:
a total of from about 0.01 wt. % to about 15 wt. % of a mixture of 3-aminopropylsilanetriol homopolymer having a chain length distribution of n=3 to about 30, 3-chloropropylsilanetriol homopolymer having a chain length distribution of n≥2, 3-(trihydroxysilyl)propyl dimethyloctadecyl ammonium chloride homopolymer having a chain length distribution of n≥2;
from about 0.01 wt. % to about 5.0 wt. % triethanolamine; and
water.