Related Experiment Video
Updated: Jul 23, 2026

Characterization of Thermal Transport in One-dimensional Solid Materials
Published on: January 26, 2014
The effect of water on the glass transition of human hair
F-J Wortmann1, M Stapels, R Elliott
1DWI at RWTH Aachen University, Pauwelsstrasse 8, D-52074 Aachen, Germany. f-j.wortmann@manchester.ac.uk
Abstract:
The glass transition of human hair and its dependence on water content were determined by means of differential scanning calorimetry (DSC). The relationship between the data is suitably described by the Fox equation, yielding for human hair a glass transition temperature of T(g) = 144 degrees C, which is substantially lower than that for wool (174 degrees C). This effect is attributed to a higher fraction of hydrophobic proteins in the matrix of human hair, which acts as an internal plasticizer. The applicability of the Fox equation for hair as well as for wool implies that water is homogeneously distributed in alpha-keratins, despite their complex morphological, semicrystalline structure. To investigate this aspect, hair was rendered amorphous by thermal denaturation. For the amorphous hair neither the water content nor T(g) were changed compared to the native state. These results provide strong support for the theory of a quasi-homogeneous distribution of water within alpha-keratins.
Related Concept Videos
States of Water
Water freezes when the intermolecular forces are greater than the kinetic energy. Unlike most other substances, water is less dense in its solid state than in its liquid state. This is because each water molecule can form...
Surface Tension, Capillary Action, and Viscosity
The various IMFs between identical molecules of a substance are examples of cohesive forces. The molecules within a liquid are surrounded by other molecules and are attracted equally in all directions by the cohesive forces within the liquid. However, the molecules on the surface of a liquid are attracted only by about one-half as many molecules. Because of the unbalanced molecular attractions on the surface molecules, liquids contract to form a shape that minimizes the number...
Phase Transitions: Vaporization and Condensation
Heating and Cooling Curves
For instance, the addition of heat raises the temperature of a solid; the amount of heat absorbed depends on the heat capacity of the solid (q = mcsolidΔT). According to thermochemistry, the relation between the amount of heat absorbed or released by a substance, q, and its...
Role of Water in Human Biology
Water's Solvent Properties
Since water is a polar molecule with slightly positive and slightly negative charges, ions and polar molecules can readily dissolve in it. Therefore, it is referred to as a solvent, a...
Accessory Structures of the Skin: Hair Growth and Types

