The Correlation Between Particle-Size Dispersity and Percolation Threshold of Brittle-Ductile Transition in Polymer Blends

Percolation threshold of Brittle-Ductile （B-D） transition and its relation with the affecting varibles （such as particle-size dispersity, interphase adhesion）in polymer blends are studied.Percolation Threshold (Φ) which is equivalent to that of B-D transition and critical matrix ligament thickness （T） are first independently calculated and the correlated equation between Φand σis also given.In addition, a new type of master curve of S（G,toughness） with Φ（stress volume fraction） for polymer blends is proposed and the new parameter Φ（up-limited stress volume fraction） is also discussed. The results confirm that Φis not only related with σ,but also tightly related with the interphase adhesion.