The morphology and mechanical properties of recyclated polyethylene/polyamide laminate

The influence of the compatibilizers on the morphology and mechanical properties of the blend of polyethylene (PE) and polyamide 6 (PA6) was studied. The waste of PE/PA6 laminate obtained after processing of barrier packaging foils was studied. The waste of PE/PA6 laminate containing 80 wt. % of PE and 20 wt. % of PA6 was processed with two compatibilizers: maleic anhydride functionalized ethylene propylene random copolymer (EPM-g-MA) and carboxyl functionalized polyethylene (PE-COOH). The compatibilizers were added to the waste in the amount of 5 wt. % or 10 wt. %. The compatibilization was performed in a Brabender plasticizer at 220 degrees C and at rotor speed of 50 rpm in a two-step mixing procedure. In the first step the blend was melted for 2 min. That was followed by the addition of compatibilizer in the second step and the mixing was continued for the next 3 min. The mixed melted samples formed thin films by compressive molding. Morphologies were examined using transmission electron microscope TESLA BS 500. The morphology was altered by an addition of compatibilizers and the system became more homogeneous. The dimensions of PA6 domains dispersed in PE matrix decreased dramatically, compared to that of uncompatibilized system. After addition of 5 wt. % or 10 wt. % of a compatibilizer to PE/PA6 blend its mechanical properties improved (twice higher Young's modulus).