Location: Cotton Fiber Bioscience and Utilization Research
2021 Annual Report
Objectives
Conduct original research to promote and enhance the use of cotton fibers in the nonwovens textile industry. Cotton fibers currently comprise ~2.4% of raw materials globally consumed for nonwovens, with the market dominated by synthetic petroleum-based fibers such as polyester (PET) and polypropylene (PP). However, the annual growth rate of cotton fiber use in nonwovens will surpass PET and PP over the next several years which present opportunities to replace petro-chemical fibers. The proposed research will include cotton fiber blending, processing, and bonding approaches, genetic selection of cotton varieties with unique fiber traits suitable for both broad use and specific nonwoven applications, and chemical modifications of cotton fibers for value added applications. Our previous cotton-based nonwovens project worked synergistically with projects in the unit and external collaborators to successfully patent and transfer cotton-based nonwoven technologies to commercially available products. These interactions will continue and will build on the success and accomplishments of our previous projects which have established a solid research foundation for cotton fiber use in nonwovens. Further investigations into the relationships between cotton fiber quality measurements and nonwovens fabric performance attributes will establish industry guidelines for cotton fiber selection, blending, and processing parameters for cotton-containing nonwovens destined for different end-use applications. This research is outlined in Objective 1 which allows for intimate stakeholder interaction and cooperative research for nonwoven prototype development toward the Agency goal of technology transfer. Objectives 2 and 3 will work together to examine value added attributes imparted by inherent genetic-based attributes and chemically added properties that enhance cotton fibers of selected varieties through nanotechnology, which ultimately relies on processing research conducted under Objective 1 for prototype development and textile functionality analyses. Cotton fiber functionalities in this research include but are not limited to inherent flame retardancy (FR) and hydrogen peroxide (H2O2) generation, high-yield nonwoven-specific cotton varieties, greige fiber color (whiteness and stability), nonwoven fabric tensile properties, stretch, drape and hand, moisture management, and new sanitization and disinfecting applications for cotton.
Objective 1: Enable, from a technological standpoint, new commercial products and market applications for cotton-containing nonwoven materials.
Objective 2: Enable new commercial varieties of cotton exhibiting non-conventional fiber properties for improved functionality and value of cotton-containing textiles.
Objective 3: Expand and develop novel metal-based nanotechnology to facilitate new value-added applications for cotton.
Approach
The increased use of cotton fibers in nonwovens textiles will be facilitated through innovative processing techniques, product prototype creation and testing, and close interaction with stakeholders at the fiber production, marketing, and manufacturing levels. Through fiber selection and blending combined with modification of nonwoven bonding processes, specialty and commodity cotton-based nonwoven fabrics can be produced which are suitable for new disposable or semi-durable applications. Raw materials will be procured from commercial sources and the in-house, commercial-grade production equipment and procedures, will be used to prepare fibrous batts for the downstream conversion of the fibers into nonwoven fabrics. The research products will be tested to assess their values for the targeted end-use products. The most promising research fabrics will be selected for confirmation before scaling to pilot operations. Selected fabrics will be offered to industrial partners for mutual cooperation and industrial trials.
Genetically diverse cotton lines will be screened to identify nonconventional fiber properties that could benefit the textile industry. Cotton fibers with specific inherent properties such as natural increased flame resistance (FR) were observed in the fibers of a cotton multiparent advanced generation intercross (MAGIC) population and will reduce the need for external applications of chemical additives to achieve the desired functionality. Additional unique fiber properties were observed in cotton fibers including elevated levels of hydrogen peroxide that would add beneficial properties to medical textiles for wound healing and infection mitigation. Other end-use properties include, but are not limited to, increased fiber elongation, enhanced absorbency and fluid handling characteristics, and development of high yield varieties specifically for nonwoven textiles. The genetic basis of the observed nontraditional fiber properties will be determined to facilitate the release of cotton varieties with properties for value-added, mostly nonwoven textile applications.
New or modified nanotechnology for cotton-based materials will be developed that increase the existing market share and create new markets. The unique chemistry and structure of various cotton varieties will be identified and utilized as a scaffold on which to build a technology enabling nanoengineered cotton products. The advantages of developing this customized nanotechnology over applying the currently available nanotechnology include comfortable and washable metal-based nanotextile products; newer functionalities; conversion of inferior or valueless cotton varieties into value-added products; decrease ecological/environmental footprints; and facilitate industry to efficiently and economically produce functional products. Based on our successful realization of cotton as a nanoengineering tool that is self-generating antibacterial silver nanoparticles, the cotton-oriented nanotechnology will be further expanded for nano-enhanced applications and the improved quality of processes and products in a sustainable manner.
Progress Report
Objective 1, significant progress was made by ARS researchers in New Orleans, Louisiana in evaluating the effects of fiber quality on nonwovens fabric performance for specific hygiene applications, including diapers and adult incontinence products. Cotton varieties were selected by ARS researchers with a broad range of fiber quality parameters including fineness, strength, length, and uniformity. ARS researchers in New Orleans, Louisiana produced mesh nonwoven fabrics from these fibers using a high-pressure water process known as spunlacing which is commonly used in commercial production of nonwovens. The cotton mesh nonwoven fabrics were subjected to standard testing with specialized instruments that evaluate different aspects of diaper topsheet performance, which is the location of skin contact. The results suggested very coarse fibers which are heavily discounted resulted in nonwoven fabrics with improved moisture fluid handling properties that more efficiently moved moisture away from the skin. The results suggest nonwovens producers can select cotton fibers with discounted pricing for improved fabric performance for hygiene applications. The selection of discounted coarse cotton fibers for nonwoven applications independent of other fiber traits such as length and strength present the opportunity to develop a commercial high-yield cotton cultivar specifically for the nonwovens industry.
Objective 2, significant progress was made by ARS researchers in New Orleans, Louisiana in measuring hydrogen peroxide generation from fibers of a diverse population of cotton lines. Different levels of hydrogen peroxide were observed by ARS researchers in fibers of cotton lines with distinctly unique genetic backgrounds suggesting a genetic basis for the trait. ARS Researchers in New Orleans, Louisiana previously demonstrated that greige cotton fibers produce low levels of hydrogen peroxide that can be useful in wound dressings to stimulate the healing process. More recently, it was demonstrated by ARS researchers in New Orleans, Louisiana project, Enhanced Cotton for Value-Added Applications that greige cotton fibers can be used in personal protective equipment such as facial coverings that offer efficacy against viruses including SARS-CoV-2. Determining the genetic basis of the inherent hydrogen peroxide generation observed in greige cotton fibers offers the opportunity to develop and release cotton cultivars with specific, enhanced hydrogen peroxide fiber profiles for would healing and personal protective applications. A high throughput screening protocol is being developed by ARS researchers in New Orleans, Louisiana that will improve the efficiency of measuring hydrogen peroxide in fibers of large cotton populations to identify promising lines for further study.
Objective 2, significant progress was made by ARS researchers in New Orleans, Louisiana in determining the genetic basis of yellowness, measured as +b, in cotton fibers. The degree of yellowness and whiteness of cotton fibers is a factor in determining the value of cotton fibers during market classification. When greige cotton fibers are used in nonwovens, particularly for hygiene applications, increased yellowness is undesirable to the consumer since it conveys an unsanitary appearance. ARS researchers in New Orleans, Louisiana have identified a gene that is linked to increased yellowness of cotton fibers. Some cotton lines with a mutation in this gene were observed by ARS researchers to have much more yellowness in their fibers compared to lines with a functional wild-type gene. A larger, more diverse population of cotton lines is currently being examined by ARS researchers to confirm the genetic linkage of the mutation with increased yellowness. This research by ARS researchers has the potential to develop a molecular marker that could be used in cotton breeding and selections to add value to cotton fibers for both woven and nonwoven markets.
Objective 3, cotton varieties were screened, and brown cotton fiber was selected by ARS researchers in New Orleans, Louisiana for the potential use in silver nanoparticles production. ARS researchers in New Orleans, Louisiana, identified that condensed tannins (naturally occurring compounds responsible for coloration in tree bark, fruits, and other plant tissues) exist in brown cotton fiber but not in white cotton fiber and developed a simple method for utilizing these condensed tannins as a reducing agent for the synthesis of silver nanoparticles. This method involves the activation of redox reactions of phenolic groups in the heated and wet fibers. The new method using brown cotton fiber has two advantages: 1) eliminating the use of toxic and expensive reducing agents that are required in the conventional synthesis of nanoparticles and 2) enabling the in situ synthesis of silver nanoparticles into the fiber.
Objective 3, silver nanoparticles with a unique size distribution were generated by ARS researchers in New Orleans, Louisiana within the cotton fiber. The functionalities and properties of nanoparticles are strongly governed by their size and size distribution, but the manipulation of particle size is a great challenge. For the first time ARS researchers at New Orleans, Louisiana, produced antimicrobial silver nanoparticles of two different sizes (8 nm and 19 nm in average diameter) at the same time, in the core (lumen) of brown cotton fiber. This new embedded system provides an opportunity for tailoring beneficial antimicrobial function, different to that from nanoparticles with a single size distribution.
Objective 3, ARS researchers at New Orleans, Louisiana, identified that silver and copper nanoparticles synthesized into cotton fibers can help decompose organic pollutant dyes in water. These metallic nanoparticles exhibited enhanced reactive properties due to their nanoscopic dimension and shape and thus were capable of removing several different types of organic dyes. This process is advantageous over conventional methods as it allows for simple extraction of the nanoparticles by filtration for easy reusability. The nanoparticles embedded in cotton fiber maintained their reactivity over several iterations of pollutant purification creating a multi-use system.
Objective 3, the effect of genetic mutation on the cotton fiber length was investigated by ARS researchers in New Orleans, Louisiana. By comparing cotton fibers collected from a wild-type and three lintless mutants, if was found by ARS researchers that calcium-rich cell wall structures or regulatory genes were considered to be one of the inhibitory mechanisms of fiber elongation. The results led to a better understanding of the synthesis of cotton fiber elongation and provided valuable tools to the cotton industry for improving cotton fiber yield and quality at the molecular level.
Accomplishments
1. Optimal processing Factors for cotton nonwoven fabrics. ARS researchers in New Orleans, Louisiana, suggests the use of cotton fibers as a raw material in disposable nonwoven fabrics has more than tripled over the last decade and is projected to continue increasing annually based on market outlook reports for disposable applications such as wipes, feminine hygiene products, and diapers. The use of high pressure water jets to produce nonwoven fabrics directly from fibers, known as spunlacing, is widely used by manufactures to create fabrics for specific end-use products such as those cited above. Using a pilot-scale spunlacing line, ARS researchers at New Orleans, Louisiana, have determined detailed and optimal processing settings specifically for the spunlacing of cotton nonwoven fabrics that enables chemical-free modification of physical properties such as strength, absorbency, and comfort. As a result of this research, major industry stakeholders including United States cotton fiber producers and nonwoven manufacturers have consulted with ARS researchers over the past year for guidance in their production processes to better meet the demands of consumers for disposable cotton-based products. ARS researchers in New Orleans, Louisiana, have provided this guidance directly and through publically distributed research articles resulting in more efficient processing of cotton fibers for specific nonwoven end-use applications. The results of these research efforts by ARS researchers and intimate stakeholder interactions have increased the demand for and consumption of United States cotton for the nonwovens industry.
2. Germ-fighting nanoenhanced cotton products. ARS researchers in New Orleans, Louisiana, believe due to the frequent emergence of new pathogens, the use of metallic nanoparticles as powerful antimicrobial agents in commercial textiles has significantly increased in recent years, with a projected market share to reach 1.1 billion USD by 2026. However, current nano-finishing methods rely on surface-coating, which results in commercial products with poor durability that lose their functionality after only a few uses. To resolve this shortcoming of current methods, ARS researchers in New Orleans, Louisiana, developed a new technology that produces permanent antimicrobial cotton products by synthesizing inexpensive copper oxide nanoparticles into the cotton fiber using no harsh chemicals. This is the first known reporting of such a new cotton system that has long-lasting antimicrobial performance (50 laundering cycles) that would be easily transferrable to large-scale manufacturing. Its invention disclosure has been approved, and the antiviral testing of this new product has been supported by the ARS Innovation Fund.
Review Publications
Rahamn, M.S., Hasan, M.S., Nitai, A.S., Nam, A.S., Karmakar, A.K., Ahsan, M.S., Shiddiky, M.J.A., Ahmed, M.B. 2021. Recent developments of carboxymethyl cellulose. Polymers. 13:1345. https://doi.org/10.3390/polym13081345.
Hron, R.J., Hinchliffe, D.J., Santiago Cintron, M., Linthicum, K., Condon, B.D. 2021. Functional assessment of biodegradable cotton nonwoven substrates permeated with spatial insect repellents for disposable applications. Textile Research Journal. 91(13-14):1578-1593. https://doi.org/10.1177/0040517520987213.
Nam, S., Park, Y., Hillyer, M.B., Hron, R.J., Ernst, N., Chang, S., Condon, B.D., Hinchliffe, D.J., Ford, E., Gibb, B.C. 2020. Thermal properties and surface chemistry of cotton varieties mineralized with calcium carbonate polymorphs by cyclic dipping. RSC Advances. 10(58):35214-35225. https://doi.org/10.1039/D0RA06265K.
Easson, M.W., Jordan, J.H., Bland, J.M., Hinchliffe, D.J., Condon, B.D. 2020. Application of brown cotton-supported palladium nanoparticles in suzuki-miyaura cross-coupling reactions. American Chemical Society Applied Nano Materials. 3(7):6304-6309. https://doi.org/10.1021/acsanm.0c01303.
Hron, R.J., Hinchliffe, D.J., Condon, B.D. 2020. Optimized hydroentanglement processing parameters for nonwoven fabrics composed entirely of cotton fibers. Journal of Engineered Fibers and Fabrics. 15:1-11. https://doi.org/10.1177/1558925020935436.
He, Z., Nam, S., Fang, D.D., Cheng, H.N., He, J. 2021. Surface and thermal characterization of cotton fibers of phenotypes differing in fiber length. Polymers. 13(7). Article 994. https://doi.org/10.3390/polym13070994.
Edwards, J.V., Prevost, N.T., Yager, D., Nam, S., Graves, E.E., Santiago Cintron, M., Condon, B.D., Dacorta, J. 2021. Antimicrobial and hemostatic activities of cotton-based dressings designed to address prolonged field care applications. Military Medicine. 186(1):116-121. https://doi.org/10.1093/milmed/usaa271.
