New polymer making method saves large amount of energy: study

WASHINGTON, May 9 (Xinhua) -- Researchers at the University of Illinois have developed a new polymer-curing process that could reduce the cost, time and energy needed, compared with the current manufacturing process.

The findings reported on Wednesday in the journal Nature require only a quick touch from a small heat source to send a cascading hardening wave through a polymer, potentially benefiting makers of cars, planes and buses who need strong, lightweight and heat resistant parts.

According to the study, the new polymerization process uses 10 orders of magnitude less energy and can cut two orders of magnitudes of time over the current manufacturing process.

"The materials used to create aircraft and automobiles have excellent thermal and mechanical performance, but the fabrication process is costly in terms of time, energy and environmental impact," said the university's aerospace engineering professor and the paper's lead author Scott White said. "One of our goals is to decrease expense and increase production."

Take, for example, aircraft assembly. For one major U.S. producer, the process of curing just one section of a large commercial airliner can consume over 96,000 kilowatt-hours of energy and produce more than 80 tons of CO2, depending on the energy source, White said.

That is roughly the amount of electricity it takes to supply nine average homes for one year, according to the United States Energy Information Administration.

"The airliner manufacturers use a curing oven that is about 60 feet in diameter and about 40 feet long. It is an incredibly massive structure filled with heating elements, fans, cooling pipes and all sorts of other complex machinery," White said.

White said the temperature is raised to about 176 degrees Celsius in a series of very precise steps over a roughly 24-hour cycle, which is an "incredibly energy-intensive process."

The researchers proposed that they could control chemical reactivity to economize the polymer-curing process.

"There is plenty of energy stored in the resin's chemical bonds to fuel the process," said Jeffrey Moore, the university's chemistry professor. "Learning to unleash this energy at just the right rate, not too fast, but not too slow, was key to the discovery."

"By touching what is essentially a soldering iron to one corner of the polymer surface, we can start a cascading chemical-reaction wave that propagates throughout the material," said White.

"Once triggered, the reaction uses enthalpy, or the internal energy of the polymerization reaction, to push the reaction forward and cure the material, rather than an external energy source," said White.

The team has demonstrated that this reaction can produce safe, high-quality polymers in a well-controlled laboratory environment.

They envision the process accommodating large-scale production due to its compatibility with commonly used fabrication techniques like molding, imprinting, 3-D printing and resin infusion. Enditem