New polymer manufacturing process saves 10 orders of magnitude of energy
Makers of cars, planes, buses — anything that needs strong, lightweight and heat resistant parts — are poised to benefit from a new manufacturing process that requires only a quick touch from a small heat source to send a cascading hardening wave through a polymer.
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, sciencedaily.com reported.
The findings, reported in Nature, state that 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.
Aerospace engineering professor and lead author Scott White said, “This development marks what could be the first major advancement to the high-performance polymer and composite manufacturing industry in almost half a century.
“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.
“One of our goals is to decrease expense and increase production.
“Take, for example, aircraft assembly. For one major US 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 CO , depending on the energy source.”
That is roughly the amount of electricity it takes to supply nine average homes for one year, according to the US Energy Information Administration.
White said, “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.
“The temperature is raised to about 176°C in a series of very precise steps over a roughly 24-hour cycle. It is an incredibly energy-intensive process.”
The team is part of the Beckman Institute for Advanced Science and Technology at the University of Illinois at Urbana-champaign and includes White, chemistry professor and Beckman Institute director Jeffrey Moore, aerospace engineering professor and department head Philippe Geubelle, and materials science and engineering professor Nancy Sottos.
They proposed that they could control chemical reactivity to economize the polymer-curing process.
Moore said, “There is plenty of energy stored in the resin’s chemical bonds to fuel the process.
“Learning to unleash this energy at just the right rate — not too fast, but not too slow — was key to the discovery.”
White added, “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.
“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.”
Sottos said, “You can save energy and time, but that does not matter if the quality of the final product is substandard.
“We can increase the speed of manufacturing by triggering the hardening reaction from more than one point, but that needs to be very carefully controlled.
“Otherwise, the meeting spot of the two reaction waves could form a thermal spike, causing imperfections that could degrade the material over time.”
The team has demonstrated that this reaction can produce safe, highquality 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, 3D printing and resin infusion. Chinese scientists have developed a fire-resistant wallpaper that not only can withstand flames, but also detect fires and trigger an alarm if a fire occurs.
The wallpaper was designed by scientists from the Shanghai Institute of Ceramics of the Chinese Academy of Sciences, according to xinhuanet. com.
Most of the wallpaper on the market today is made of highly flammable materials such as plant cellulose fibers or synthetic polymers, which can spread the fire rather than preventing it.
The new wallpaper can withstand a high temperature of 1,000°C. It is made of an inorganic fireresistant hydroxyapatite nanowire paper and a graphene oxide temperature sensor.
The sensor is attached to the back of the wallpaper through a simple drop-casting process using an ink containing graphene oxide. It is then connected to the metal wire as an electrode.
Graphene oxide is not electrically conductive at room temperature, but can become conductive at high temperatures, triggering the fire alarm device.
The wallpaper is highly flexible and can be made into various shapes, dyed different colors, and printed with commercial printers.
The research was published in the journal ACS Nano in March.
Zhu Yingjie, the team leader, said that although the wallpaper is still in the early research phase, the research team is exploring low-cost mass production technology.
Zhu added, “We are also investigating more applications of the new fire-resistant inorganic paper, which might be used in other fields such as preserving important paper documents, battery separators, flame-retardant fiber-optic cables, catalytic paper, and flexible electronics.”