DYNAMIC VULCANIZATION OF PP EPDM BLENDS - EFFECT OF CROSS-LINKING DEGREE ON PROPERTIES OF TPV/

Thermoplastic vulcanizates (TPV) contain finely dispersed micron-size crosslinked rubber particles in a thermoplastic matrix. This occurs by additional breakdown of rubber induced by dynamic vulcanization durin g its melt-mixing with thermoplastic component. Rubber is thus turned into the dispersed inner phase. The effect of crosslinking in PP/EPDM TPV on the dynamic properties is shown at various temperatures above t he melting point, strain amplitudes and frequencies. These properties also provide means for assessment of the melt morphology. Heterogeneit y of the system, affecting molecular dynamics, is explored by the ESR spin probe method.