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Nanotube rubber is stretchy at extreme temperatures
来源: | 作者:nanocarbon | 发布时间: 2017-10-24 | 774 次浏览 | 分享到:
　　Researchers at the National Institute of Advanced Industrial Science and Technology (AIST) in Ibaraki, Japan, have developed a novel viscoelastic material that remains stable over a wide temperature range, from -96[degrees]C to 1000[degrees]C. This is the first material of its kind, as rubbery materials like these normally break down at high temperatures and become brittle when too cold.

　　Scientists have been studying carbon nanotubes for the last 20 years because they have many properties including extremely high tensile strength and high electrical conductivity. Now, Ming Xu of AIST has discovered yet another exceptional property in these tubes, namely viscoelasticity over a wide temperature range.

　　Viscoelastic materials behave like thick liquids, but are also reversibly elastic, such as rubber bands. One example of such a material is polymer foam--widely used in earplugs that adapt themselves to the shape of the ear yet recover their original form after they are removed. Viscoelasticity is seen in a variety of materials, including amorphous and semicrystalline polymers, some biomaterials, crystals and even some metallic alloys.

　　The AIST rubber is made from a random network of interconnected single-, double- and triple-walled carbon nanotubes and has the same viscoelasticity as that of the most thermally resistant silicone rubber at room temperature. However, silicone rubber only retains its viscoelasticity between -55[degrees]C and 300[degrees]C. The AIST material remains flexible over a much higher temperature range, can recover its shape after being repeatedly deformed and shows excellent fatigue resistance.

　　According to the team, the network is highly stable over a broad temperature range thanks to the energy dissipated as the individual nanotubes zip and unzip at the points of contact. The carbon nanotubes themselves are also highly heat-resistant-between 2000 [degrees]C and 3000[degrees]C -so an even broader temperature range might be possible for this rubber.

　　Potential applications for the rubber are uncertain--the material is totally new and unique with hitherto unseen properties.
　　
　　For further information, contact: the National Institute of Advanced Industrial Science and Technologies, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568, Japan. Tel: 81-(2)-9861-2000. http://www.aist.go.jp

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