Sorbothane

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Sorbothane is the brand name of a synthetic viscoelastic urethane polymer used as a shock absorber and vibration damper. It is manufactured by Sorbothane, Inc., based in Kent, Ohio.

Contents

History

Sorbothane was invented and patented in 1982 by Dr. Maurice Hiles, [1] a British inventor. It was prepared by mixing polyol and isocyanate. [2] His research into the energy dissipation properties of human soft tissue disclosed a structure very similar to an interpenetrating polymer network. This led to his synthesis of the first commercial simultaneous interpenetrating network, now called Sorbothane. [3] Dr. Hiles wrote in his patent "The resulting solid polymer behaves like a quasi-liquid, being readily deformed by an applied force and slow to recover, although in the absence of such a force it takes up a defined shape and volume". In 1976, he contacted the National Research Development Corporation (NRDC) about his invention; the NRDC spent almost £10,000 in helping him to improve and patent the polymer. BTR Industries obtained the license from NRDC for selling them. [2]

Properties

The material combines some of the properties of rubber, silicone, and other elastic polymers. It is considered to be a good vibration damping material, an acoustic insulator, and highly durable. An unusually high amount of the energy from an object dropped onto Sorbothane is absorbed. The feel and damping qualities of Sorbothane have been likened to those of meat.

Sorbothane is a visco-elastic material, meaning that it exhibits properties of both liquids (viscous solutions) and solids (elastic materials), with a relaxation time of two seconds. [4] Because visco-elastic behavior is desirable in shock and vibration applications, many materials claim to be viscoelastic; however, many of these materials have only trace viscoelastic properties.[ citation needed ]

Similar materials include polynorbornene, Noene, and Astro-sorb.

Uses

Sorbothane has many industrial applications, from acoustic shielding to machine mounts. It has been used to quiet personal computers by being packed around the hard drive and other noisy spinning components. Sorbothane damps vibration transmission from vibrating hardware. In addition, Sorbothane has been used by NASA to isolate vibration, [5] [6] in the Air Force Memorial, [7] and to transport the Liberty Bell. [8] It is currently used with insoles and heel pads to absorb impacts during sports activities such as football, cricket, and rugby.[ citation needed ] It is also used in recoil pads of guns. [9]

See also

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References

  1. ↑ U.S. Patent 4346205A
  2. 1 2 "Inventor fleshes out plan for better boots". New Scientist. Reed Business Information. 6 December 1979. p. 778. ISSN   0262-4079 . Retrieved 28 June 2012.
  3. ↑ Smock, Doug (13 August 2009). "Unique Urethane Dampens Shocks and Noise". designnews.com. Archived from the original on 3 September 2009.
  4. ↑ Cinats, J; Reid, DC; Haddow, JB (1987). "A biomechanical evaluation of sorbothane". Clin Orthop Relat Res (222): 281–8. PMID   3621732.
  5. ↑ Houston, Janice; Gattis, Christy (5 January 2004). Passive Isolators for Use on the International Space Station (PDF). 42nd AIAA Aerospace Sciences Meeting and Exhibit. Reston, Virigina: American Institute of Aeronautics and Astronautics. doi:10.2514/6.2004-787.
  6. ↑ "Sorbothane Protects NASA Components During Launch". Sorbothane Insoles. 14 May 2019. Retrieved 27 October 2022.
  7. ↑ "Designing the Perfect Memorial: Sorbothane & the Air Force Memorial - www.sorbothane.com". www.sorbothane.com. 23 July 2019. Retrieved 27 October 2022.
  8. ↑ "Vibration Solutions - www.sorbothane.com". www.sorbothane.com. 3 February 2015. Retrieved 27 October 2022.
  9. ↑ James Russell (1 January 1998). Precision Shooting: The Trapshooter's Bible : for the Advanced Trapshooter & Those who Strive to be ... James Russell Publishing. p. 107. ISBN   978-0-916367-10-7 . Retrieved 28 June 2012.

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