**4.1 Effect of stirring on hydrothermal experiments (HTP-2 process technique) on unirradiated PA-TFC for different durations**

Hydrothermal reaction by alkaline hydrolysis is heterogeneous two phase reaction. The intensity of turbulence in the liquid phase would decide the extent of resistance offered by the interface between the phases. Hydrothermal reaction was carried out using 50% caustic solution using polyamide TFC tokens. The reaction was carried out both under static and dynamic conditions and observed results are shown in **Figure 5**. There is an improvement in degree of depolymerisation of more than 50% under stirring speed of 330 RPM at temperature of 50°C.

**Figure 5.** *Effect of stirring on HTP-2 process technique.*
