Microplastics have become one of the greatest environmental challenges worldwide. To turn this dramatic damage around, EU regulators now want to ensure that plastic itself is fully recyclable or biodegradable. The aim of the present work is to develop a biobased and biodegradable biocomposite based on commercial polyhydroxyalkanoates (PHAs) and nanoclays, with the objective of achieving a reduction of rancid odour while avoiding any loss in thermomechanical properties, thus tackling two key disadvantages of PHAs. This research aims at completely characterising the structural, thermal and mechanical behaviour of the formulations developed, understanding the compatibility mechanisms in order to be able to assess the best commercial combinations for industrial applications in the packaging and automotive sectors. We report the development of nine nanobiocomposite materials based on three types of commercial PHA matrices: a linear poly(3-hydroxybutyrate) (P3HB); two copolymers based on poly(3-hydroxybutyrate)-co-poly(4-hydroxybutyrate) (P3HB-co-P4HB); and nanoclays, which represent a different polar behaviour. Dispersion achieved is highly relevant compared with literature results. Our findings show impressive mechanical enhancements, in particular for P3HB reinforced with sepiolite modified via aminosilanes.

The aim of this research paper is to study the behaviour of a common used biopolymer (Poly(Lactic Acid) (PLA)) after several reprocesses and how two different types of additives (a melt strength enhancer and a nanoadditive) affect its mechanical and rheological properties. Systematic extraction of extrudate samples from a twin-screw compounder was done in order to study the effect in the properties of the reprocessed material. Detailed rheological tests on a capillary rheometer as well as mechanical studies on a universal tensile machine after preparation of injected specimens were carried out. Results evidenced that PLA and reinforced PLA materials can be reprocessed and recycled without a remarkable loss in their mechanical properties. Several processing restrictions and specific phenomena were identified and are explained in the present manuscript.

Finishing process (Grinding and Polishing), is still manually performed, specially in free form surface parts. This involves a series of remaining problems, mainly related with the geometrical shape of the finished part.In traditional manually finishing task, the final quality aspect of the part is the only parameter to be controlled. This supposes a lack in the quality parameter control, mainly in high level parts, as in automotive, aeronautics or mould making parts. Manual finishing has not any control about the amount of material removed, during finishing process, affecting this way to the final geometrical shape of the product.This is the reason why this investigation proposes an exhaustive research of the parameter influencing the finishing tasks, and defining a finishing methodology adapted for an automatic process executed by a spherical robot. Making it an automatic way, and controlling paths, tool, abrasive, and defining a mathematical model for the finishing process, final quality of the part and product will be optimized, from a quality point of view, at the same time process time and cost is reduced