Due to the well-known hygroscopic nature of polyamides, moisture penetrates the polymer matrix. It has been previously found that the effect of sorbed water on the structure and physical properties of polymers is not negligibly small, and sometimes irreversible. Furthermore, during processing, the water content has a significant influence on the viscosity and continued molecular weight growth in the melt due to the recombination reaction. With the growing demand for unreinforced and reinforced polyamides in high-performance applications, it is critical to understand the physics of the interaction between water molecules and polymer during extrusion. Time-dependent linear-viscoelastic properties of the amorphous polyamide with varying initial moisture content showed an exponential increase with time, suggesting recombination reaction. High-resolution 13C NMR in a neutral solution of 2,2,2-Trifluroethanol and deuterated chloroform was performed to investigate number average molecular weight and structural changes in the amorphous polyamide. This time-temperature-moisture content relation can be leveraged in twin-screw extrusion to induce beneficial chemical changes. No previous work has combined the kinetics of post condensation with the governing factors of devolatilization (such as shear, melt surface area). The research bridges this gap via in-situ rheological analysis and controlled devolatilization during twin-screw extrusion of amorphous polyamide.