Antimicrobial phenolic fatty acid-based epoxy curing agents for epoxies
Inventors
Huang, Kun • Ashby, Richard D. • Fan, Xuetong • Lew, HELEN N. • Moreau, Robert A.
Assignees
US Department of Agriculture USDA
Publication Number
US-12012369-B2
Publication Date
2024-06-18
Expiration Date
2040-08-21
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Abstract
Compositions containing at least one compound of formula Iwhere R1 is a phenolic compound (e.g., simple phenol, creosote, thymol, or carvacrol), and where R2 is a polyamine (e.g., ethylenediamine (EDA), diethylenetriamine (DETA), triethylenetetramine (TETA), tetraethylenepentamine (TEPA), hexamethylenediamine (HDA)); and optionally a carrier; the compositions may additionally contain at least one epoxy resin. Methods for killing microorganisms involving contacting the microorganisms with an effective microorganism killing amount of the above composition. Compositions containing at least one compound produced by a method involving reacting phenolic-branched chain fatty acid methyl ester with at least one polyamine.
Core Innovation
The invention disclosed relates to compositions containing compounds of formula I, where R1 is a phenolic compound such as simple phenol, creosote, thymol, or carvacrol, and R2 is a polyamine including ethylenediamine (EDA), diethylenetriamine (DETA), triethylenetetramine (TETA), tetraethylenepentamine (TEPA), or hexamethylenediamine (HDA). These compositions may optionally include a carrier and can contain at least one epoxy resin. Methods for killing microorganisms are also described, which involve contacting microorganisms with an effective microorganism-killing amount of these compositions. Moreover, compounds produced by reacting phenolic-branched chain fatty acid methyl ester with polyamines form part of the disclosed compositions.
The problem addressed is the limitation of conventional antimicrobial agents which often have residual toxicity, volatility, chemical instability, or photolytic degradation. There is a need for antimicrobial polymers that are bio-based, environmentally friendly, chemically stable, nonvolatile, and non-migratory, offering prolonged efficacy and minimizing environmental problems. Current antimicrobial epoxy polymers often use petroleum-based monomers that are not biodegradable. Thus, the invention aims to fill the research gap by providing bio-based epoxy curing agents containing phenolic groups that impart antimicrobial activity to epoxy polymers, achieving effective bacterial inhibition while improving environmental compatibility.
Specifically, the invention reports the synthesis of antimicrobial phenolic-branched chain fatty acid-based epoxy curing agents via amidation of phenolic-branched chain fatty acid methyl esters with polyamines such as EDA, resulting in curing agents that impart antimicrobial functionality to commercial epoxy resins like bisphenol A based diglycidyl ether of bisphenol A (DGEBA). It demonstrates through testing that such epoxy polymers exhibit effective antimicrobial activity against both Gram-positive and Gram-negative bacteria, depending on the curing agent composition and reaction conditions, thereby providing durable antimicrobial epoxy coatings.
Claims Coverage
The patent contains multiple inventive features disclosed across independent claims related to antimicrobial epoxy polymers, their compositions, and methods of killing microorganisms.
Antimicrobial epoxy polymer with phenolic fatty acid-based curing agent
An antimicrobial epoxy polymer comprising a curing agent having the structure of formula I, wherein the curing agent incorporates a phenolic group (e.g., simple phenol, creosote, thymol, carvacrol) and a polyamine group such as ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, or hexamethylenediamine.
Composition containing phenolic-polyamine compounds and epoxy resin
A composition comprising at least one compound of formula I with R1 as a phenolic compound and R2 as a polyamine, optionally including a carrier and at least one epoxy resin such as bisphenol A type epoxy resin (e.g., diglycidyl ether of bisphenol A).
Method for killing microorganisms using phenolic epoxy compositions
A method for killing microorganisms involving contacting microorganisms, including Gram-positive or Gram-negative bacteria, with an effective microorganism killing amount of the antimicrobial epoxy composition containing phenolic-polyamine compounds described above.
Overall, the claims cover innovative antimicrobial epoxy polymers incorporating phenolic fatty acid-based curing agents, the compositions comprising such compounds optionally with epoxy resins, and methods of microbial inhibition using these compositions. The features emphasize specific chemical structures of curing agents and their antimicrobial utility.
Stated Advantages
Provides antimicrobial epoxy polymers with prolonged efficacy, chemical stability, and non-volatility, overcoming limitations of low molecular weight biocides.
Bio-based curing agents reduce environmental impact and residual toxicity compared to petroleum-derived polymers.
Polymers exhibit durable antimicrobial activity without leaching harmful small molecules, enhancing safety and functionality.
Allows incorporation of antimicrobial functionality through curing agents, maintaining convenience and versatility in epoxy resin applications like coatings and adhesives.
Documented Applications
Sterilization and antimicrobial coatings, particularly antimicrobial epoxy polymer coatings that inhibit Gram-positive and Gram-negative bacteria.
Use of antimicrobial compositions for killing microorganisms on objects or surfaces in water sterilization, public sanitization, and preservation contexts.
Applications in food preservation, water treatment, and sanitary coatings where durable, nonvolatile antimicrobial properties are required.
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