| Résumé : |
The dynamic, low-deformation, tensile modulus of raw bovine corium was measured in various states of static elongation and dehydration from neutral and low pH. The data were analyzed by comparing the overall change in fiber orientation during stretching, as determined by small angle light scattering, with yhe number of fibers that are pulled straight while subject to interfiber adhesions. The wet rawhide at pH=7, which contained 164 percent water based on dry weight, elongated with little overall fiber orientation, but its modulus increased by two orders of magnitude when stretched by 20 percent, showing the effects of progressive growth in the number of straightened fibers. The modulus at 20 percent elongation increased only 2 fold in the presence of 60 percent (v/v) isopropanol, showing a greater effect of interfiber adhesion, which hindered the movement and straightening of fibers. Within experimental error the maximum values of the moduli of samples in 0%, 60%, and 100% isopropanol, at 20 percent elongation, were the same, showing the equivalence of fiber adhesion. The hide shrank more when solvent-dried from an acid-swollen state (pH=3), but the interfiber adhesion wazs lowered, as seen in the behavior of the fibers when the dried material was stretched. These results explain the properties of solvent-dried hides in terms of the movements of the hide fibers when the dried hide is deformed, and have implications for process design and product quality. |
Aller sur edunet
Accueil
Fiber orientation and small-deformation modulus of stretched, partially-dried hide in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXXXIII (Année 1988)
