ANALYSIS OF DISTRIBUTION OF WATER IN HAIR 47 refl ection in the diffraction pattern is attributed to the organization of the protofi laments in the cortical cells of hair. Amount of water in these regions of IFs appears to be relatively small compared to the total amount. A larger fraction of water appears to be present in the mesopo- rous regions, as indicated by the high-intensity near-zero scattering angles. Obvious features that correspond to the mesoporous entities in hair can be associated with the medullary struc- tures, which are likely to be more hydrophilic and thus interact positively with water. Other mesoporous entities are the cracks generated by fi ber damage, both in the cortex and the en- docuticle region of the cuticle cell. Further SANS experiments with carefully prepared and well-characterized hair samples and analysis of the data could provide a detailed distribution of water in regions other than the IFs. Figure 7. IR spectra of hair. (A) Exposed to D2O, and then (B) immersed in boiling water.

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