Antibacterial Soybean‐Oil‐Based Cationic Polyurethane Coatings Prepared from Different Amino Polyols

Abstract

Antibacterial soybean-oil-based cationic polyurethane (PU) coatings have been successfully prepared from five different amino polyols. The structure and hydroxyl functionality of these amino polyols affects the particle morphology, mechanical properties, thermal stability, and antibacterial properties of the resulting coatings. An increase in the hydroxyl functionality of the amino polyols increases the cross-link density, resulting in an increased glass transition temperature and improved mechanical properties. Both the cross-link density and the amount of ammonium cations incorporated into the PU backbone affect the thermal stability of PU films. PUs with the lowest ammonium cation content and highest cross-link density exhibit the best thermal stability. With some strain-specific exceptions, these PUs show good antibacterial properties toward a panel of bacterial pathogens comprised of Listeria monocytogenes NADC 2045, Salmonella typhimurium ATCC 13311 and Salmonella minnesota (S. minnesota) R613. S. minnesota R613 is a "deep rough" mutant lacking a full outer membrane (OM) layer, an important barrier structure in gram-negative bacteria. With wild-type strains, the PU coatings exhibit better antibacterial properties toward the gram-positive Listeria monocytogenes than the gram-negative S. minnesota. However, the coatings have excellent activity against S. minnesota R613, suggesting a protective role for an intact OM against the action of these PUs.

Thermo‐Mechanical and Antibacterial Properties of Soybean Oil‐Based Cationic Polyurethane Coatings: Effects of Amine Ratio and Degree of Crosslinking

“…Typhimurium to PUD activity can be explained by the outer membrane (OM) of this Gram‐negative bacterium, which serves as an additional permeability barrier to exogenous compounds. The absence of an OM in Gram‐positive bacteria such as L. monocytogenes and S. aureus allows more ready uptake of antimicrobials by these bacteria and is consistent with earlier findings by Xia et al…”

“…However, there is a minimal change in the temperature of the maximum rate of weight loss, T max . The samples with the highest relative ratios of ammonium groups had more pronounced derivative peaks for ammonium decomposition (below 200 °C) and dissociation of urethane bonds (200–320 °C) . Figure displays the weight‐loss and derivative weight‐loss curves as a function of temperature for PU films prepared with different MSOL hydroxyl numbers.…”

“…A further study from our group examined the effects of the hydroxyl functionality of the soybean oil‐based polyols on the thermal and mechanical properties of cationic polyurethanes . We recently reported the first study on the effect of different polyols on the antibacterial properties of cationic plant‐oil based PUDs and PU coatings . In our previous work, cationic PUDs were prepared using different amine polyols, while the molar ratios hydroxyl (OH) groups from the amine polyols, OH groups from the soy polyol and the isocyanate (NCO) groups from the isocyanate were held constant .…”

“…[17] We recently reported the first study on the effect of different polyols on the antibacterial properties of cationic plant-oil based PUDs and PU coatings. [21] In our previous work, cationic PUDs were prepared using different amine polyols, while the molar ratios hydroxyl (OH) groups from the amine polyols, OH groups from the soy polyol and the isocyanate (NCO) groups from the isocyanate were held constant. [21] In the current work, environmentally friendly, plant oil-based, cationic PUDs with excellent coating properties have been successfully synthesized from soybean oil-based polyols.…”

Polypropylene Nonwoven Fabric@Poly(ionic liquid)s for Switchable Oil/Water Separation, Dye Absorption, and Antibacterial Applications

“…[43] Applications of cationic polymers as antibacterialm aterials have been extensivelys tudied due to their broad-spectrum antibacterial properties without developing bacterium resistance. [43] Applications of cationic polymers as antibacterialm aterials have been extensivelys tudied due to their broad-spectrum antibacterial properties without developing bacterium resistance.…”