Abstract: Abstract, The effect of phenol resin on the properties of dynamic vulcanized PP/EPDM/SEBS elastomer was studied.  With increasing phenol resin content，the hardness and tensile strength first increased and then remained constant; elongation at break,  tear strength,  and melt flow index decreased，compression  set  first  decreased  and  then  increased.  The  PP/EPDM/SEBS vulcanized with 10phr phenol resin was characterized with excellent compression set，which were respectively 23. 9%and 28. 3%at 70℃and 125℃，about 9. 8%and 20. 7%lower than those without SEBS.  The viscosity of vulcanizing system decreased with increasing shear rate.  With increasing phenol resin content，the viscosity first increased then decreased，and the maximum value was observed at 10phr phenol resin.

Key words: polypropylene, ethylene-propylene-dime tripolymer, styrene butadiene styrene copolymer(saturated);octylphenol-formaldehyde resin, dynamic vulcanization