聚酰胺6特殊的屈服特性

It has long been known that the tensile deformation of thermoplastics is often characterized by the appearance of only one yield point， which is generally accepted as a point of initiation of ‘permanent non-recoverable plastic deformation’。In particular，double yielding phenomena were observed in several groups of semicrystalline polymers。In this work， we reported the existence of two distinct yield points before necking in injection molded specimens of Polyamide 6 and its blending systems with small portion of glass bead and polyolefin elastomer respectively under tensile loading。 The double yielding was probably in correlation with the tensile velocity，blending composition， the degree of crystallinity and the crystal form。It seemed that higher tensile velocity，increasing the elastomer content，increasing the crystallinity content all depressed the phenomenon of double yielding。