Nylon,fatigue behavior

T Harmia. Fatigue behavior of neat and long glass fiber (LGF) reinforced blends of nylon 66 and isotactic PP. Polymer Composites 17 926-936, 1996. 

With this subtle behavior in mind, we may now address this question do not the present findings disagree with the well-known fact (15,16) that the fatigue life of nylon 66 is monotonically decreased by Increasing the water content within the range of this study First, it must be noted that the fatigue tests quoted in references 22 22 conducted on smooth, un-notched... 

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... 

---