The invention discloses modified PP, a preparation method thereof and a twin-screw extruder used for preparing the modified PP. The modified PP is prepared from, by weight, 22-36 parts of PP resin, 25-37 parts of EPDM, 10-45 parts of talcum
powder, 12-23 parts of
polycarbonate, 11-19 parts of
polyamide, 9-16 parts of modified polyphenylene
ether, 13-22 parts of
thermoplastic polyester, 1-7 parts of a stabilizer, 2-9 parts of a compatibilizer and 2-7 parts of an
antioxidant. The modified PP and the preparation method thereof have the advantages that by adopting the PP resin, the EPDM, T15 and the
polycarbonate, the advantages of high
impact,
weather resistance, high mobility and sprayability can be improved; by adopting the PP resin, the EPDM, T20 and the
polyamide, the advantages of high rigidity,
weather resistance, scratch resistance and low
odor can be improved; by adopting the PP resin, the EPDM, T30 and the modified polyphenylene
ether, the advantages of rigidity and
toughness balance and
low shrinkage can be improved; by adopting the PP resin, the EPDM, T40 and the
thermoplastic polyester, the advantages of high melt value, low
odor and rigidity and
toughness balance can be improved; the rigidity of a
system is improved, and the molding
shrinkage rate is reduced, thereby obtaining the reinforced PP material with excellent comprehensive performance.