Issue Date: June 7, 2004
THE LIVES OF OUR FABRICS
In the middle of the 20th century, cotton farmers--and fashionistas--everywhere were facing a serious crisis. Wrinkle-resistant synthetic fibers had usurped the throne of King Cotton, plunging its market share in retail apparel and home furnishings from two-thirds to one-third. But owing largely to chemical research done at the Southern Regional Research Center (SRRC), New Orleans, to impart cotton with durable-press and flame-retardant features, that share had bounced back to more than 60% by 2000.
On May 14, the American Chemical Society designated SRRC--part of the U.S. Department of Agriculture's Agricultural Research Service (ARS)--a National Historic Chemical Landmark for this work. Scientists involved in the research joined ACS dignitaries and representatives of the Louisiana state government and the U.S. Congress to celebrate the occasion.
"In recognition of the pioneering and diverse work of the many different researchers who are responsible for actually making cotton the 'fabric of our lives,' it is my pleasure to designate the evolution of durable-press and flame-retardant cotton--the research done here at the Southern Regional Research Center--a National Historic Chemical Landmark," ACS President-Elect William F. Carroll Jr. said in the final speech of the morning ceremony before unveiling a commemorative plaque.
Pointing out his own wrinkle-resistant cotton shirt, Carroll added that SRRC's research helped secure a future for cotton fabric at a time when naysayers were predicting that it would disappear completely.
The plaque reads: "By the 1950s, synthetic fabrics--often wrinkle resistant and flame retardant--began to overtake cotton as the dominant U.S. textile fiber. To reverse this trend, chemists and chemical engineers at the Southern Regional Research Center initiated research to modify cotton chemically. Their efforts in developing agents that crosslinked cellulose fibers and in establishing crosslinking mechanisms led to improved durable-press fabrics. SRRC studies also developed new agents that improved the durability of flame retardant cotton to laundering. These significant advances in the properties of cotton enabled this natural fiber to remain a highly competitive textile."
ACS District IV Director Paul R. Jones and SRRC Director John P. Jordan also spoke at the ceremony, which included a presentation by the U.S. Navy Color Guard and a symposium outlining the highlights of SRRC's cotton research.
Cotton is a natural seed fiber composed mostly of cellulose microfibrils that is breathable and comfortable and dyes easily. But because cellulose chains in cotton are held together only by hydrogen bonds, natural cotton is easily deformed by wrinkling or laundering.
Progress at SRRC came in steps, explained SRRC collaborator Robert M. Reinhardt. Cotton with increased wrinkle resistance was developed first. Then scientists made "wash and wear" cotton; garments of this fabric would remain smooth after washing. Finally, durable-press cotton--with the ability to hold a crease--was developed.
SRRC scientists started with surface treatments, using polymer-forming reagents to impart the desired properties. But eventually they turned to processes that penetrated to form cross-links between nearby cellulose molecules. Many of the agents used were formaldehyde derivatives, which were cheap and effective. But because these compounds were unstable, they were slowly released during processing and storage of cotton fabric, raising health concerns.
SRRC scientists then pursued strategies for minimizing or eliminating formaldehyde release during cotton processing, said Noelie R. Bertoniere, research leader for SRRC's Cotton Textile Chemistry Research Unit. These refinements dramatically cut the amount of formaldehyde release, but completely formaldehyde-free techniques are still rare because reagents are expensive.
Ralph J. Berni, another SRRC scientist, explained the center's efforts at making cotton flame-retardant. In response to requests from the U.S. military, the center chemically bonded flame retardants to the cotton surface and deeper within its structure, while preventing stiffness, roughness, and strength loss. A number of materials that were developed were used in early spaceflights and are still in use.
"SRRC has published more than 1,500 scientific papers and patents in the field of durable-press and flame-retardant finishing of cotton to date," Berni said. The center continues to conduct research to solve problems associated with such chemical modifications to cotton.
Louisiana Lt. Gov. Mitchell J. Landrieu and Rep. David Vitter (R-La.), though unable to attend in person, sent written remarks as part of the ceremony.
"Although I was certainly aware of your great research at the center, I was still amazed to read the complete list of accomplishments that you produced," Vitter wrote. "Your work is important because of the importance of cotton and cotton fabrics to our nation. How fitting it is that your research is actually taking place in Louisiana, a state where cotton is such an important part of our economy."
SRRC is the third ARS facility to be noted by ACS's landmark program, which since 1992 has recognized nearly 50 important places, discoveries, or achievements in the history of chemistry. In 1999, the ARS research center in Peoria, Ill., shared the honor with London's St. Mary's Hospital for their discovery and development of penicillin, and in 2002, the Western Regional Research Center was noted for its time-temperature tolerance studies that improved the quality of frozen foods.
It's hard to believe that something as ubiquitous as cotton faced obsolescence. SRRC's research helped preserve cotton as a viable fabric and saved the livelihoods of farmers and tailors alike.
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