Several compatibilizers were tried but they improved properties mainly in PP-rich zones, performances still far below pure ABS. The major point is the weak interaction between ABS and PP due to their chemical differences leading to poor mechanical properties. Apart from strain at break, most of ABS properties are seriously impaired with PP incorporation. Some studies were reported about ABS/PP blends, focusing on PP-rich systems or exploring the whole range by 10 or 20 wt% steps. As the most present plastic after styrenics (ABS, HIPS and their blends, ABS/PC, HIPS/PPE…) and bringer of strong incompatibility because of its different nature, PP (polypropylene) was chosen for the role of contaminant. Īs one of the most present polymers within WEEE and owing to its potential added value because of its properties, ABS (acrylonitrile-butadiene-styrene) is here considered as the material to be valorized. In the area of 3D printing, recycling plastics has become increasingly important as this technology can produce large quantities of polymer wastes (support structures, parts with defects). However, even a few percent of impurities can be detrimental to mechanical properties as most polymers are incompatible. High purity rates of sorted polymers are probably unattainable, especially as purity and yield are often contradictory notions. Strong occurrence of toxic and/or environmentally harmful and now forbidden (or soon to be) brominated flame retardants within polymeric parts is also a serious barrier to waste management as it is unconceivable to reemploy these contaminated materials. Moreover, the rapid increase of tonnages, the potential toxicity of these products, and the presence of valuable materials as precious metals strongly motivate the establishment of proper end-of-life management scenarios. Dismantling these devices is a complex subject. Waste of Electrical and Electronic Equipment (WEEE) Plastics (WEEP) are not currently intensively regenerated through mechanical recycling for several different reasons. The addition of PP-g-MA modifies the local properties and possibly conduct to a premature breakage of the polymer blend. The main result is that PP introduced at 4 wt% into ABS does not alter the static mechanical properties despite polymers incompatibility. Comparison between the determinist model results and the experimental data (strength, volumetric variation) shows that this type of modelling could be a predictive tool in order to anticipate composite mechanical properties and to understand micromechanisms of deformation (damage, cavitation). ABS and PP were individually characterized from tensile tests instrumented with photomechanics and their behaviors were modelled through a set of numerical parameters (elasto-visco-plasticity with a Gurson’s criterion behavior). A finite element model was developed from the mechanical behavior of each component. PP-g-MA was introduced in the blend to improve the compatibility. In this work, an ABS matrix (major plastic in Waste of Electrical and Electronic Equipments) was filled with 4 wt% of PP to mimic impurities in ABS after recycling. Yet, such rates may be detrimental to functional properties.
Very high purities (<2 wt%) are difficult to reach. However, sorting technologies bear costs and meet limits. Recycling of plastics is hindered by their important variety and strong incompatibility.
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