Abstract
1. The construction of an apparatus (elastometer) for the mechanical investigation of high elastic substances is described. This apparatus makes it possible to draw deformation curves and curves of the relaxation of stress atconstant temperature and in different gaseous media, and also to investigate the life at multiple deformations. The sensitivity of the apparatus is: ΔP=0.01 g., Δl=0.01 cm. 2. The molecular weight of the segments of the chains between the bonds of the spatial network of the vulcanizate, calculated by means of Flory's equation, increases with swelling, and approaches a certain maximum value. This is evidence of the rupture of the local intermolecular bonds on swelling. 3. The maximum time of relaxation, calculated according to the equation of Dogadkin, Bartenev, and Reznikovskil, as a consequence of swelling, generally does not change uniformly; it decreases with swelling of natural rubbers in benzene and chloroform in the initial stages, then increases, and finally decreases again in the last stages of swelling. 4. An increase of temperature displaces the minimum times of relaxation to lower degrees of swelling. 5. The increase of the maximum time of relaxation as a result of swelling causes a decrease of the life of the vulcanizate; a decrease of this factor is accompanied, at least within certain limits, by an increase of life. 6. Swelling causes a decrease of tensile strength and of the relative elongation of vulcanizates. 7. The changes recorded above in the equilibrium and kinetic characteristics of high elastic deformation are explained by the presence in the vulcanizate of different intermolecular bonds.
Elastic deformation plays a non-negligible role in Greenland’s outlet glacier flow