TENSILE CREEP AND CREEP-RUPTURE OF CONTINUOUS STRAND MAT POLYPROPYLENE COMPOSITES

This paper describes an experimental study on the tensile creep behavi or of a random continuous fiber mat reinforced polypropylene composite , commercially known as Azdel. A special experimental setup was design ed and used to conduct these creep tests at 75 and 100 degrees C with stress levels ranging from 30 to 60 percent of the tensile strength of Azdel. The test duration was 3,000 hours or the time to creep rupture response, whichever occurred first. A straight line on a semi-log plo t adequately described the relationship between the imposed stress and the creep rupture response time for the range of stress levels studie d. Moreover, the estimated secondary creep rate was inversely related to the observed creep rupture response time.