Polyamide composition and article made therefrom with improved mold shrinkage

A polyamide composition comprising:

• a polyamide (PA1),
• a polyamide (PA2) having a glass transition temperature Tg which is lower than the Tg of the polyamide (PA1) and/or having a melting temperature Tm which is lower than the Tm of the polyamide (PA1), and
• from 15 percent by weight (wt. %) to 60 wt. % of a glass fiber, said wt. % being based on the total weight of the polyamide composition,
• wherein the polyamide composition has a PA1 weight ratio of at least 0.05 and at most 0.95, said PA1 weight ratio being calculated as the weight of PA1 in the polyamide composition based on the combined weights of PA1 and PA2 in the polyamide composition,
• wherein the polyamide (PA1) is a copolyamide comprising:
• recurring units (RPA1) of formula (1), (RPA2) of formula (2), and (RPA3) of formula (3) or (4):
• wherein n1 to n3 are mol. % of recurring units (RPA1), (RPA2) and (RPA3), respectively;
• or a copolyamide comprising:
• recurring units (RPA1) of said formula (1), (RPA2) of said formula (2), (RPA3*) of formula (5), and (RPA4*) of formula (6),
• wherein n1 to n4 are mol. % of recurring units (RPA1) (RP,A2), (RPA3*), and (RPA4*), respectively (n1+n2+n3+n4≤100 mol. %);
• and
• wherein
• R1 is a C4 to C8 aliphatic alkylene;
• R2 is a C9 to C12 aliphatic alkylene group;
• R5 is a C1 to C3 alkylene group;
• R″, at each location, is independently selected from the group consisting of an alkyl, an aryl, an alkali or alkaline earth metal sulfonate, an alkyl sulfonate, and a quaternary ammonium;
• j is an integer from 0 to 10;
• T in Formula (3) is represented by either one of the following formulae (7) or (8):
• wherein
• R3 and R4, are independently selected from the group consisting of a bond and a C1 to C10 alkylene groups;
• R′, at each location, is independently selected from the group consisting of an alkyl, an aryl, an alkali or alkaline earth metal sulfonate, an alkyl sulfonate, and a quaternary ammonium;
• and
• each i is an independently selected integer from 0 to 10;
• and the ‘*’ denotes a bond to one of the two explicit nitrogen atoms in Formula (3).