2010 Annual Report
1a.Objectives (from AD-416)
Design and create molecules that afford nonwovens resiliency in use and protection against open flames and microbial attack; design and prepare cotton-based polymer systems compatible with elastomers to generate new binary fibers and waterproof breathable membranes to make the products more useful as technical textiles; design and create cotton-derivatives that are water repellent and reactive with epoxies, isocyanates, and inorganic materials and explore their uses in making adhesives, coatings, and composites; and eliminate the need for sizing warp yarn for weaving. Develop processes for producing nonwoven fabrics from greige cotton.
This objective contributes to the 2010-2015 NP 306 Action Plan Component 2. Fibers, Problem Statement 2B: New or Improved Technologies, Processes or Products.
1b.Approach (from AD-416)
The project will pursue research along four avenues. The first deals with generating molecules that impart dimensional stability and flame and microbial resistance to cotton, so that the new cotton derived materials pass or surpass in-use, stability, non-flammability, and antimicrobial test standards, as well as gain industrial acceptance. The second deals with polymer modified cotton fibers to enable cotton's use in new technical textiles, such as waterproof microporous membranes. The third searches for new water-repellent cotton derivatives that are reactive with epoxies, isocyanates, and inorganic materials for uses in adhesives, coatings, and composites. The fourth avenues focuses on eliminating sizing agents in warp yarn preparation to make weaving and textile operations efficient by creating reduced friction machine parts.
New flame-resistant chemical compounds have been synthesized and tested for flame resistance (FR) performance on cotton. Several large- and small-molecule systems show new promise in their FR and antimicrobial (AM) performance and permanence on cotton fabrics. Use of cotton fiber as a composite material substrate has been investigated. A fiber-reactive FR molecule was invented. Applications of existing and new FR and antimicrobial chemical systems on cotton nonwoven substrates have been completed. These treated substrates are intended for use in mattresses and upholstery. The effectiveness of non-washable and yet durable (for many years) FR treatments on virgin cotton was measured and determined to be satisfactory. Layer-by-layer nano applications of chemicals for attaining certain specific fabric attributes, such as FR and AM characteristics, have been investigated with satisfactory results on (Mathis) commercial wet-processing (lab) apparatus and equipment. A new, pilot-scale nonwovens production and (chemical) finishing facility has been established. The facility now includes, beside the existing fiber opening, cleaning and carding systems, a needle-punch machine, a state of the art hydro-entanglement (water-based) processing system, and a variety of laboratory equipment for special chemical treatments of fabrics. A number of 100% cotton nonwoven fabrics have been produced and tested in the in-house facilities. Some of the research products were developed by using a mechanically, pre-cleaned cotton. A couple of the research products, made with both a classical virgin greige cotton, as well as a pre-cleaned greige cotton, have led to considerable commercial interest by the industry.
The research on size-free weaving, as documented last year, was redirected towards development of cotton-based nonwovens to increase value-added utilization of cotton.
Economics of Using Discounted Cottons and Cotton Derivatives (Byproducts, e.g., Ginning Motes and Linters, Comber Noils, Mill Processing Wastes, Etc.). Sub-grade cottons, cotton ginning byproducts (motes, linters), and cotton processing/recycling wastes cannot be used in the traditional textile manufacturing involving spinning, weaving and knitting. Hence, these cottons and cotton derivatives literally fetch nothing (~30 to 10 cents a pound, respectively), compared to what a regular, good-quality, standard cotton fetches (~60 cents to a dollar a pound). Based on preliminary investigations, it appears that these discounted forms of cotton, either with or without special processing treatment, may be profitably utilized in certain nonwoven products, such as the household, industrial, and personal-hygiene wipes, mobile textiles, mattress pads, automotive components, and the like.
Economical Fabrication of Fire-Retardant/Fire-Barrier Cotton-Rich Fabrics/Pads for Mattresses and Furniture. A low-cost, flame-retardant, cotton-rich nonwoven pad has been developed by optimally using commercially available fire-retardant (FR) chemicals and fibers. The pad has passed the California-legislated standard flammability tests for mattresses. An Agreement of Confidentiality with a U.S. firm has been signed to explore its commercial application.
Feasibility of Processing Virgin Greige Cotton on Commercial Nonwovens Production Equipment. Presently, less than 1% of baled (greige) cotton production in the United States (and perhaps in the world, as well) is used in fabricating nonwoven fabrics. Preliminary research conducted at the new cotton nonwovens research facility in SRRC, ARS, USDA, has shown that greige cotton can be efficiently processed on existing nonwovens production equipment with some relatively minor modifications in fiber processing. A few nonwoven products of mostly greige cotton content have been successfully produced for certain special-purpose applications, such as sew-in quilts and blankets and 3-dimensional coforms for industrial wipes. These products have generated measurable interest in the nonwovens industry. Commercially successful incorporation of cotton – a natural, sustainable fiber – in these nonwoven products is expected to promote increased use of cotton in nonwovens, which ultimately will benefit the cotton growers, ginners, and users.
Sawhney, A.P., Reynolds, M.L., Slopek, R.P., Condon, B.D., Hui, D. 2010. Advent of Greige Cotton Nonwovens Made By Hydro-Entanglement Process. Textile Research Journal. 80(15):1540-1549.
Sawhney, A.P., Singh, K.V., Pang, S., Sachinvala, N.D., Condon, B.D., Li, G. 2008. Modern Applications of Nanotechnology in Textiles. Textile Research Journal. 78(8):731-739.
Chang, S., Sachinvala, N.D., Sawhney, A.P., Parikh, D.V., Jarrett, W., Grimm, C.C. 2007. Epoxy Phosphonate Crosslinkers for Providing Flame Resistance to Cotton Textiles. Polymers for Advanced Technologies. 18:611-619.
Sachinvala, N., Parikh, D.V., Sawhney, A.P., Chang, S., Mirzawa, J., Jarrett, W., Joiner, B. 2007. Silver(I) Antimicrobial Cotton Nonwovens and Printcloth. Polymers for Advanced Technologies. 18:620-628.
Kamath, M., Bhat, G., Parikh, D.V., Condon, B.D. 2009. Processing and Characterization of Flame Retardant Cotton Blend Nonwovens for Soft Furnishings to Meet Federal Flammability Standards. Journal of Industrial Textiles. 38(3):251-262.
Jiang, N., Chen, J., Parikh, D.V. 2009. Acoustical Evaluation of Carbonized and Activated Cotton Nonwovens. Bioresource Technology. 100(24):6533-6536.