The novel compatibilization of high impact polypropylene/high density polyethylene (PP/ EPR)/PE blends by high shear process leads to a typical core-shell structure, with PE core encapsulated by EPR shell within PP matrix, a decrease of the size of (PE/EPR) domains as well as an improvement of the interface being observed when increasing screw rotation speed from 300 to 600 rpm. Possible in situ formation of copolymers can be an explanation for the improved miscibility between phases. Further, the addition of only 3 wt.-% of ethylene-octene copolymer (EOC) to the (PP/EPR)/PE blend processed at 600 rpm increases elongation at break and impact strength by respectively 80 and 100% as EPR and EOC could play a synergetic role. This novel process offers new perspectives for lightening and recycling.

SbstractAn efficient recycling of end-of-life products is of crucial interest from an economical and ecological point of view. However, the near infrared spectroscopy often used for the optic sorting processes is limited because of the absorption of carbon black present in black plastics and as it only sorts as a function of chemical formulas. The tracing technology developed in this study is based on the dispersion of lanthanide complexes particles into polymers to give them a code that can be related to their formulation and viscosity that are important parameters for their re-processing. As the success of this technology is conditioned by achieving a fine dispersion of the tracer particles, we also focus on accomplishing a fine dispersion of tracer particles by using a high shear process. Processing under high shear rate (N= 800 rpm) has proved to play a determining role in dispersing finely and homogenously tracer particles within PP matrix. Thanks to the good quality of dispersion, the detection of three tracers at a level of 0.1 wt% has been successfully achieved, even in black matrices for an acquisition time of 10 ms.

The aim of this article is to upgrade the performance of polypropylene/ethylene propylener ubber (PP/EPR) blends by addition of hydrophobic nanosilica (SiR805) and using \ high shear processing technology" .T he morphological developments, mechanical and rheological properties of these composites were investigated as afunction of processing conditions. High shear processing has proved to be an efficient process to decrease the size of the dispersed phase (EPR) up to 300 nm and to disperse finely nanosilica particles to less than 30 nm especially at 800 min -1 .M oreover, the morphology stability of the nanocomposite is ascribed to the formation of ac ore shell structure (EPR nodules =core; nano-silica =shell) and selective location of nanosilica at the interface. More importantly, this core-shell structure is favoured to enhance the impact strength of the (PP/EPR)/3 wt% SiR805 nanocomposite. In agreement to the obtained morphology, the improvement (about 60 %) of elongation at break attests ag ood adhesion between phases due to high shear effect as highlighted by viscoelastic properties. Therefore, high shear processing technology has proved to be ar elevant method to prepare nanocomposites with high performances without adding any additive and offers new perspectivesf or recycling and lightening structures.