
New Liquid Epoxies Created from Cane Sugar
By Jan Suszkiw June 10, 1999WASHINGTON, June 10--Sugar
(sucrose) extracted from sugarcane juice is the main ingredient in new liquid
epoxies that can bind wood, metal, glass, concrete and other materials,
U.S. Department of Agriculture scientists
and collaborators report. The advance may open a new industrial outlet for the sweetener in the form
of base coats, primers or adhesives for composite materials like particle
boarding or boat hulls. Its an example of science finding a
surprising new use for a common, everyday agricultural commodity, said
Floyd P. Horn, administrator for the Agricultural Research Service, the USDA
agency carrying out the project. More than three million tons of American cane sugar is produced annually,
but less than 2 percent is used for non-food purposes, such as fermentation. As
a food product, cane sugar has to compete with artificial and low-calorie
sweeteners. What sucrose offers that the other sweeteners do not is an abundant,
chemically pure source of raw material for creating epoxies that can bind with
such diverse materials as wood or plastic, says lead scientist and chemist
Navzer D. Sachinvala, at the ARS
Southern Regional
Research Center in New Orleans. Once these epoxies set, they become clear glassy or rubbery materials,
depending on the type used, Sachinvala says. Its too soon to say how the new epoxies will fare in a market
dominated by petroleum- based products. But Sachinvala cites a few selling
points, notably the sucrose epoxies lack of ingredients like Bisphenal-A,
a component of petroleum-based products. Controversy surrounds the chemical
because of its alleged role in disrupting the reproductive system of mice and
possibly humans. Other sucrose epoxy benefits include an ability to cure or harden in
conditions from below room temperature to 150 degrees Celsius. Lab tests
indicate the epoxies are also capable of remaining stable under direct exposure
to sunlight and saltwater, Sachinvala reports. Results from studies published in the
Journal of Polymer Sciencealso indicate bonding strengths comparable to those of the petroleum product
diglycidyl ether of Bisphenal-A, or DGEBA. One of the sucrose epoxies tested,
called a crotyl monomer, outperformed the DGEBA product by 30 percent. Sachinvala began exploring cane sugars industrial potential in 1988,
first as a Case Western Reserve Universitygraduate student, and later as a scientist at Hawaiis Agricultural
Research Center (HARC) in Oahu. In 1996, he joined ARS New Orleans
center. There, along with HARC scientists Othman Hamed and David Winsor,
Sachinvala perfected an epoxidation process that employs reagents like
oxygenated vinegar to change sucroses molecular structure and chemical
properties. Negotiations with an industrial partner are underway to produce large
amounts of the sucrose epoxies so commercial criteria like price and
performance can be determined and compared to existing materials. A more
detailed article appears in the June issue of Agricultural Research, ARS
monthly publication and on the web at: http://www.ars.usda.gov/is/AR/archive/jun99/epox0699.htm Scientific contact: Navzer D. Sachinvala, ARS Southern Regional
Research Center, New Orleans, La., phone (504) 286-4324, fax (504) 286-4271,
[email protected].
Story contacts Jan R Suszkiw U.S. Department of Agriculture | |