Jerry P. Moreau

Cotton Nonwovens as Oil Spill Cleanup Sorbents

We examined partial or complete replacement of synthetic sorbents by cotton- containing nonwovens for use in oil spill cleanup. The results indicate that with light crude oil, oil sorption capacities of the needlepunched cotton-containing sorbents were slightly greater than those of sorbents made from 100% polypropylene fibers. If necessary, a small portion of polypropylene fiber could be incorporated into nonwovens to increase mechanical strength properties and to maintain fabric integrity. The cotton- containing sorbents were reusable after a simple mechanical compression to remove oil. They also floated in an artificial seawater bath for a long period of time. We found that oil sorption of cotton fiber was controlled by adsorption on the fiber surface and capillary action through its lumen. Contrarily, the main mechanism for polypropylene was through capillary bridges between fibers. Detailed evaluation using an environ mental scanning electron microscope confirmed this mechanism. Individual bundles of both cotton and polypropylene fibers sorbed more oil than did the needlepunched nonwoven fabrics prepared from the respective fibers. In addition, sorption decreased as needling density increased. This study provides preliminary data for investigating other cotton nonwoven constructions with improved oil sorption properties.

Biodeterioration of Nonwoven Fabrics

The use of nonwoven fabrics in disposable, convenience products generates high quantities of wastes that are not biodegradable. Synthetic fibers provide a major source of materials for these disposable products. Because synthetics are generally less bio degradable than natural fibers, it appears that for maximum degradability, natural fibers are a likely choice of materials for disposable goods. To compare rates of bio deterioration for natural and synthetic fibers, we examined changes in the structure and strength of nonwoven fabrics containing cotton and polypropylene, a synthetic fiber widely used in nonwovens, after controlled exposure of fabrics to fungi normally found in soil. Fungi grew extensively only on cotton fibers. Fungal growth rates were highest on 100% cotton and decreased to zero on 100% polypropylene. Significant losses in strength occurred only in samples with a high cotton content. Progression of cotton fiber deterioration was followed using the microscope until only polypropylene . fibers remained in the fabrics.

Research on Polymers as Sizing Agents—Laboratory to Loom

Earlier research on the development of durable polymeric sizing agents for room temperature application to cotton yarns has been expanded to full warp slashing and weaving evaluation. Weaving of yarns treated with high concentra tions of a low-temperature-cure polyacrylate, with a glass transition temperature of 0°C, were unsuccessful. Trials using a similar polyacrylate with Tg, 33°C and/or a polyurethane with film forming temperature of 28°C have been much more en couraging. Film properties of various formulations have been described and treated yams have been evaluated for breaking strength, elongation, and abrasion resistance.

Comparison of Sized Open-End and Ring Spun Yarns

Cotton open-end (OE) yarns of 4.5 and 5.0 T.M. and a ring yarn of 4.5 T.M. were treated with polyvinyl alcohol (PVA) and carboxymethyl cellulose (CMC) each at yarn counts of 8, 14.5, 21, and 27.5. The treated yams were compared with controls by testing for breaking strength, elongation, tenac ity, and abrasion resistance. Comparisons were also made between the three types of yarn. Properties of treated OE yarns compared to untreated ring yarns of the same count are presented and the feasibility of using durable chemically treated OE yarn instead of untreated ring yarn is discussed.

Partially Durable Oil-Repellent Finish for Cotton

The well-known reactivity of tris(1-aziridinyl)phosphine oxide (APO) both with cotton cellulose [4] and carboxylic acids [8] has served as a basis for a study of the modification of cotton fabric with APO in conjunction with perfluorooctanoic acid (PFOA). The fabric used was a 68 X 72 desized, scoured, and bleached printclotly (3.2 oz/yd=). Solid APO, obtained by stripping solvent from an 80% solution in ethanol (Dow Chemical Company 1 ), and technical grade PFOA (Matheson Coleman and Bell ) were used in the treating formulations. Each reagent was separately dissolved in 20% (w-w) aqueous acetone before final mixing; catalysts, when used, were added just prior to the final dilution. Solutions were applied by conventional padding, followed by drying for 5 min at 80°C and curing. A 30-min hot water wash was employed after the curing step. ’

Flame Retardant for Cotton Based On Thpoh and Guanazole

3,5-Diamino-1,2,4-triazole, commonly known as guanazole was found to polymerize very readily with THPC and THPOH. At pH 2.8, THPC and guanazole solutions formed a gel within 30 min. The solutions were more stable as the pH was increased, reaching a maximum stability of 20-24 hrs. at pH 9.0 at room temperature (26-28°C) before polymer separation. The solution stability was greatly reduced at temperatures of 34°C or more. The solutions were considered to contain THPOH at pH values of 7.0 or above. Cotton fabric was treated with THPOH-guanazole by a pad-dry-cure procedure. A solution pH of 9.0 was considered to be optimum since the pad bath was most stable at this pH. The reaction on cotton is rapid and efficient at temperatures ranging from 140-160°C. The fabric had excellent flame-retardancy, which was very durable to repeated laundering. For example, 4 oz. cotton flannelette with an add-on of 15% had a 2.6 in. char length after 50 launderings as measured by AATCC Test Method 34-69. An add-on of about 20% is required to pass the.Childrens Sleepwear Flammability Standard, DOC FF 3-71. The finish is very sensi tive to chlorine; therefore, the fabric should not be bleached with hypo chlorite.