An X-Ray Diffraction Study of Thermally-Induced Structural Changes in α-Keratin

  • Kay Sue Lee Gregorski
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 86A)


A series of events takes place as wool is heated under vacuum from room temperature to 250°C: Loosely and strongly bound water molecules are removed at temperature at and below 150°C; a glass transition of the amorphous keratin occurs at 160–175°C; helices melt at 215 and 235°C. The structural changes take place between the glass transition and the helix melting temperature are observed as reflected in the low-angle X-ray diffraction patterns: the 39 A meridional reflection is intensified; a 4-point diagram at azimuthal angle of 45 degree with spacing around 46 A appears; the intensity of the 33 A meridional reflection decreases, and the 66 A meridional reflection is the most heat-resistant.


Differential Thermal Analysis Seal Tube Wool Fiber Acidic Amino Acid Residue Wool Keratin 
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Copyright information

© Plenum Press, New York 1977

Authors and Affiliations

  • Kay Sue Lee Gregorski
    • 1
  1. 1.Agricultural Research Service, U. S. Department of AgricultureWestern Regional Research LaboratoryBerkeleyUSA

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