Characteristic of the extrusion of polyethylene modified with halogen
free flame retardants and additives
Polimery 2003, No 7-8, 540
The effects of commercial halogen free flame retardants (two grades of aluminum oxide and magnesium hydrooxide, Table 1) and three auxiliary materials acting as external lubricants (Table 2) on the course and efficiency of medium density polyethylene (PE-MD) extrusion process have been investigated. The relations between polymer pressure in the extruder head (p), screw torque (M), polymer flow rate (mass flow - G and volume flow - W) and the type and concentration of flame retardant (50-60 wt. %) and auxiliary material (Table 3, Fig. 1 and 2) were characterized. Aluminum hydroxide Martinal OL-107c appeared to be most advantageous because it least affected the increase in p and M values. It has been stated that auxiliary materials used improved the extrusion process. The amounts of lubricants used should not exceed 0.8 wt. %.
Keywords: extrusion, halogen free flame retardants, external lubricants, medium density polyethylene, screw torque, polymer flow rate
Characteristic of the extrusion of polyethylene modified with halogen free flame retardants and additives