Polystyrene fatigue behavior

L. H. Sperling, J. A. Manson, G. M. Yenwo, N. Devia-Manjarres, J. Pulido, and A. Conde, Novel Plastics and Elastomers from Castor Oil Based IPN s A Review of an International Program, in Polymer Alloys, D. Klempner and K. C. Frisch, eds.. Plenum, New York (1977). Castor oil-urethane/polystyrene sequential IPNs. Synthesis, morphology, and mechanical behavior. Fatigue behavior. 

Foden E, Morrow DR, Sauer JA. The effect of molecular weight on the fatigue behavior of polystyrene. JAppl Polym Sci 1972 16 519-26. 

A few controlled studies on the effects that cross-linking has on the FCP resistance have been done. When irradiation was used to increase Afw in polyst5Tene, keeping constant, the fatigue life was affected very little by the total dose applied. In fact, the FCP behavior did not alter significantly even up to the gel point and beyond. The FCP resistance of cross-linked polystyrene is lower than... 

Confirmation of the general fatigue superiority of semicrystalline polymers is implicit in studies of a-N behavior at frequencies low enough to minimize temperature rises (169). While the ratios of the endurance limit to tensile strength for typical amorphous polymers (polystyrene, PMMA, and cellulose acetate) are approximately 0.2, values for nylon-6,6, acetal resin, and polyterafluoroethylene are 0.3, 0.5, and 0.5, respectively. At a low frequency, polyethylene (Mw > 50,000) exhibits no failure after 5 x 10 cycles, even at the relatively high alternating stress... 

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