Resins for improved flow in injection molding

A method for making a molded article comprising:

• flowing a polymer feed to a mold;
• regulating the mold temperature via heat exchange with water at inlet temperature of water to the mold below 100° C.;
• and
• recovering a molded article from the mold, wherein an absolute value of ΔRV of the molded article as compared to the polymer feed is from 0 to 5, the RV determined according to ASTM D789;
• wherein the molded article comprises
• nylon-6,6, and
• a section having a thin elongated profile comprising
• a thickness of up to 1.5 mm, and
• a flow length of at least 25 cm.

A polyamide resin comprising:

• from 90 to 99.9 wt. % polyamide condensation product of diacid and diamine;
• from 3 to 200 ppmw phosphorus, present as an oxyphosphorus compound;
• and
• from 800 to 3000 ppmw acetic acid end groups on the polyamide;
• wherein the polyamide resin has amine end groups (AEG)≤N milliequivalents per kg (meq/kg) of the polyamide resin, where N is selected from integers from 40 to 50, inclusive.

A polyamide resin comprising:

• from 90 to 99.9 wt. % polyamide condensation product of diacid and diamine;
• from 3 to 200 ppmw phosphorus, present as an oxyphosphorus compound;
• and
• from 800 to 3000 ppmw acetic acid end groups on the polyamide;
• wherein the polyamide resin has a RV from 26 to 42, the RV determined according to ASTM D789.