Quality assessment of recycled and modified LDPE/PP blends

An experimental study was conducted to investigate the morphology, thermal and mechanical properties of recycled polyolefin blends with different prehistory modified with ethylene propylene rubber (ethylene-propylene diene monomer (EPDM)) using the differential scanning calorimetry (DSC), wide angle X-ray scattering, Fourier transform infrared spectroscopy (FTIR), scanning electron microscope and mechanical methods. The efficiency of the modification was investigated as a function of the modifier content in the range from 7 wt% to 15 wt%. DSC results show that the single polymers are not clean material and contain some quantity of another polyolefins. In the processing and exploitation conditions, there is an increase in imperfect crystals in the postconsumer waste polypropylene. FTIR provides clear evidence about the oxidative processes and mechanical destruction during exploitation and blending. The obtained results proved that the technological and postconsumer wastes could be successfully reused as blends by the addition of EPDM.

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