Accession Number : AD0621194

Title :   MECHANICAL PROPERTIES OF POLYMER NETWORKS,

Corporate Author : WISCONSIN UNIV MADISON

Personal Author(s) : Ferry,John D.

Report Date : 1964

Pagination or Media Count : 13

Abstract : The equilibrium elastic properties of polymer networks (stated always with the reservation that true elastic equilibrium is difficult if not impossible to achieve experimentally) are influenced by network defects, notably free strand ends and certain entanglements which appear to be closely related to the coupling entanglements present in uncross-linked polymers of high molecular weight. The time-dependent mechanical properties in small deformations also reflect these defects, and the entanglements may be the primary source of the mechanical losses in rubbery networks which persist to far lower frequencies than could be expected from the motions of individual network strands. At higher frequencies, in the transition between rubberlike and glass-like behavior, the presence of a network affects mechanical properties to a comparatively slight degree, but the presence of the cross-links causes a perceptible decrease in the short-range mobility of the polymer chains. (Author)

Descriptors :   (*POLYMERS, MECHANICAL PROPERTIES), ELASTIC PROPERTIES, TRANSFORMATIONS, MOLECULAR STRUCTURE, DEFORMATION, RUBBER, GLASS, PHASE STUDIES, FREQUENCY

Distribution Statement : APPROVED FOR PUBLIC RELEASE