Abstract
The importance of rubber and rubber-like substances for packings as shock-absorbers between parts of machinery, in short, the use of rubber under compression in mechanical construction is continually increasing. Several methods have already been proposed to investigate the behavior of rubber under these conditions, and the most ingenious method seems to be a two-dimensional stretching of rubber films in the form of balloons (Sheppard and Clapson, Ind. Eng. Chem., 24, 782 (1932)). This deformation is identical to homogeneous compression if volume changes by the deformation may be disregarded. The latter does not hold true if inactive fillers are used, which give rise to vacuoles in stretching but not in compression. However, in practice homogeneous compression is rare, as the material will never be able to glide without friction along the compressing parts to which in many cases the rubber is vulcanized. Because of the complicated deformation of rubber in practice, it is necessary to imitate the real conditions under which compression takes place. for these reasons a simple compression of cylindrical specimens between parallel plates was chosen as a first basis for the investigations.