Publication Date:
2009-03-21
Description:
Improved electrically powered artificial muscles are needed for generating force, moving objects, and accomplishing work. Carbon nanotube aerogel sheets are the sole component of new artificial muscles that provide giant elongations and elongation rates of 220% and (3.7 x 10(4))% per second, respectively, at operating temperatures from 80 to 1900 kelvin. These solid-state-fabricated sheets are enthalpic rubbers having gaslike density and specific strength in one direction higher than those of steel plate. Actuation decreases nanotube aerogel density and can be permanently frozen for such device applications as transparent electrodes. Poisson's ratios reach 15, a factor of 30 higher than for conventional rubbers. These giant Poisson's ratios explain the observed opposite sign of width and length actuation and result in rare properties: negative linear compressibility and stretch densification.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Aliev, Ali E -- Oh, Jiyoung -- Kozlov, Mikhail E -- Kuznetsov, Alexander A -- Fang, Shaoli -- Fonseca, Alexandre F -- Ovalle, Raquel -- Lima, Marcio D -- Haque, Mohammad H -- Gartstein, Yuri N -- Zhang, Mei -- Zakhidov, Anvar A -- Baughman, Ray H -- New York, N.Y. -- Science. 2009 Mar 20;323(5921):1575-8. doi: 10.1126/science.1168312.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Alan G. MacDiarmid NanoTech Institute, University of Texas at Dallas, Richardson, TX 75083, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/19299612" target="_blank"〉PubMed〈/a〉
Keywords:
Biomimetic Materials/chemistry
;
Elasticity
;
Muscle, Skeletal
;
*Nanotubes, Carbon/chemistry
;
Static Electricity
;
Temperature
;
Tensile Strength
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
