RUPTURE CHARACTERISTICS OF RUBBERLIKE POLYMERS

PART I. MODIFICATION OF SMITH'S METHOD OF REDUCED VARIABLES FOR ULTIMATE PROPERTIES

Abstract

Smith's method of describing the temperature- and the extension rate- dependences of the ultimate properties of vulcanized rubbers is somewhat modified to reserve the general applicability. As for the stress at break and the horizontal shift factor, log a_T, respectively, that defined as true stress and that obtained separately from the data on the loss tangent measurements are recommended instead. Besides the horizontal shift factor, a vertical shift factor, log b_T, is newly introduced to form a logarithmic composite plot of strain at break versus extension rate from the data obtained at various temperatures.
That the failure envelope is not a material function for the rupture characteristics but is to be regarded as a material function for the non-linearity of the elasticity is pointed out, though it appears to be suitable for its name.