3.3.1. Melt spinning
The production of monofilaments from polymer blends by melt
spinning is a challenge in terms of effective cohesion and phase
stability between blend components. For that purpose, a mini-twin
screw extruder equipped with dedicated monofilament die and a
high speed winding unit was used. In accordance with normal
procedure, different extrusion configuration parameters (temperature
profile, screw speed and die diameter) were investigated in
order to produce a consistent mono-filament capable of being
attached to the winding unit. Attempts to produce mono-filaments
using uncompatibilized blends were complicated while consistent
CA-based mono-filaments were obtained using compatibilized
blends of pCA/pPVOH (Entries 5 and 7 in Table 3). Actually, only
compositions containing a compatibilizer were capable to be
readily fibre-processed, which fully confirmed the ability of MAg-
PLA to improve the polymer blend processability. Filaments with a
diameter of less than 400 mm were prepared by adjusting both
torque and spinning speed of the winding unit. It is also noteworthy
that the processing of mono-filaments starting from CA/HEC blends
was unsuccessful due to the brittleness of the polymer strand
recovered immediately after the extruder die.