Data on the linear viscoelastic relaxation of wool fibers for a range of relative hu midities below the gas transition (Tg) are systematized by a humidity-time superposition method. The differences in the relaxation behavior in water where the fiber is above its Tg are pointed out. The analysis relates to the properties of the water sensitive, viscoelastic component of the wool fiber and consists of superimposing the relaxation curves for different humidities onto the curve for the dry state by multiplicative scaling and shifting on the logarithmic scale of the reduced time variable λ, that corrects for the influence of ageing. The change of the scaling and shift factor with the absorption mechanism of the water is discussed.
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