Polymer composition and molded part made thereof

A polyamide polymer comprising a blend of at least two polyamides having an overall monomer composition represented by one of the notations ZT/CT, ZT/CT/ZI/CI, ZT/CT/BT, and ZT/CT/BT/ZI/CI/BI, wherein

• X represents a linear aliphatic C4-C5 diamine
• Y represents a linear aliphatic diamine with at least 6 carbon atoms,
• Z represents a linear aliphatic diamine with at least 4 carbon atoms,
• wherein (Z) is at least one of (X) and (Y);
• I represents isophthalic acid;
• T represents terephthalic acid;
• B represents a branched diamine;
• and
• C represents a cyclic diamine, and wherein
• the polyamides comprise:
• 0-35 mole % (I) and 65-100 mole % (T), relative to the total molar amount of (I)+(T), and either
• 15 mole %-80 mole % (X), 0-70 mole % (Y), 10-40 mole % (C), and 0-30 mole % (B), relative to the total molar amount of (X)+(Y)+(B)+(C);
• or
• 0-20 mole % (X), 10-80 mole % (Y), 15-40 mole % (C) and 0-30 mole % (B) and relative to the total molar amount of (X)+(Y)+(B)+(C) with the proviso that Y represents a linear aliphatic diamine with 9 or 10 carbon atoms, and wherein
• the polyamide polymer has a glass transition temperature (Tg) of at least 145° C. and a dynamic modulus (E′), measured at a temperature (Tmod) equal to Tg+15° C., in the range of 100 MPa-700 MPa, wherein both Tg and E are measured by dynamic mechanical thermal analysis (DMTA) according to the method of ASTM-D5026-15.