An estimate of the strength of polymers

Abstract

Based on the kinetic theory of fracture, the equation σ th = ( 1 s )( 4rE c U 3n ) 1 2 was used to calculate the theoretical strength, σ th, of polymers using the crystal lattice modulus, E c, the activation energy of thermal degradation, U, and the cross-sectional area, s, of a polymer chain with r taken as the length of a C-C bond and n as unity. The influences of stress concentration and thermal fluctuation on the strength were determined and it was found that both of them could not be neglected.