Rheological, Mechanical and Morphological Characterization of Monopolymer Blends Made by Virgin and Photo-Oxidized Polypropylene

Abstract

In this work, monopolymer blends of virgin polypropylene and photo-oxidized polypropylene were prepare and characterized. The polypropylene samples were subjected to accelerated ageing to simulate the effects of outdoor exposure of polypropylene. After exposure, samples were pelletized and mixed with the same virgin polymer. The rheological, mechanical and morphological characterization was conducted on both the polymers and the blends. Both viscosity and mechanical properties decrease with increases in the content of recycled, photo-oxidized components and of the level of degradation of this component. In addition, the experimental data were compared with a model that takes into account both the effect of the change of the molecular weight and of the presence of oxygenated groups.

Special Issue “Feature Papers in Recycling 2021”

“…The results show that metal caps are mainly made of iron and aluminum, while plastic caps were made by polyethylene (high-density HDPE and lowdensity LDPE), with a few particles of polypropylene (PP). The plastic's densities ranged between 0.752 and 0.956 g/cm 3 , while aluminum and iron materials had significantly higher densities of 1.66-1.97 g/cm 3 and 4.43 g/cm 3 . Slight reductions in the density values of the metal particles can be attributed to the inside plastic coatings.…”

“…Therefore, the content of recycled PP is limited and the prediction of the properties of these recycled/virgin blends is challenging. In [3], the authors prepared and characterized monopolymer blends of virgin and photo-oxidized PP. The samples were characterized in terms of mechanical and rheological properties (elastic modulus, tensile strength, elongation at break, viscosity, degree of crystallinity).…”

Toward the Decarbonization of Plastic: Monopolymer Blend of Virgin and Recycled Bio-Based, Biodegradable Polymer

“…As it can be observed, the comparison with experimental values is good. Thus, the adopted model can predict the mechanical property values of these monopolymer blends quite effectively, provided that the chemical nature and morphology of the reprocessed components do not change significantly [31].…”

Recycling of poly(lactic acid)/poly(butylene succinate) (PLA/PBS) blends with high amounts of secondary raw material

“…8 Some processing technologies of polymeric materials, such as cast extrusion and thermoforming (used to produce disposable products), are characterized by a high percentage of "post-process" waste material. The recovery of these materials, combined with virgin polymers, is a practice that is commonly applied with fossil plastics 9,10 as the properties of the final product are not significantly altered. Single-use packaging products produced by PLA-based materials have been commonly utilized worldwide in recent decades, which has consequently generated considerable PLA waste.…”