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The main aim of this research work is to assess the potential of a distillery waste from thyme as multifunctional filler in natural fiber reinforced plastics (NFRP) with biobased polyethylene matrix. Several ethylene-based copolymers with different co-monomers (vinyl alcohol, methyl methacrylate, glycidyl methacrylate and acrylic acid) were used as compatibilizer agents to overcome the lack of compatibility between the highly hydrophobic matrix and the highly hydrophilic lignocellulosic filler. The effect of the compatibilizer type and amount, as well as the lignocellulosic filler content was followed by thermal, mechanical, morphological and rheological characterizations. In addition to the typical filler effect, thyme also provides a remarkable increase in thermal stability at moderate temperatures with a positive effect on widening the processing window. The compatibilizer agent that offers best balanced properties is the glycidyl methacrylate copolymer with a noticeable increase in stiffness, flexural and tensile strength. Regarding processability, the viscosity increases with the filler content. This is highly important at low shear rates but the effect is almost negligible at high shear rates typical of injection molding processes.

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The injection process is a conformation process of thermoplastic polymeric materials that has great economic and technologic significance. Much research has been devoted to determining the optimal process conditions. On the other hand, the recycled polymeric materials, produced at the end of a product's life, are an important source of prime materials that can be used to obtain products with good quality and low costs as compared to conventional products. Taking both aspects into consideration, this study has been dedicated to the material study and modeling, in order to determine the parameters used during the processing. A rheological behavior model of the different blends has been developed that can be calculated from simple laboratory tests, whose results have been used as a simulation parameter of the injection process.

Injection molding of recycled thermoplastic materials is a possible alternative for the manufacture of new products and is becoming increasingly important in the industrial sector. Due to the ease with which recycled materials can be mixed, and as so little is known about the process characteristics required to obtain products in optimum conditions, this paper proposes an evaluation criterion for the processability of different blends of recycled materials (ABS/PC blends). With this aim in view, a multicriteria optimization methodology has been developed to evaluate and determine the optimum process conditions that guarantee the ideal final qualities of the products considered from different aspects. The results obtained are used to determine the material processability index of the blend (MPI).

Brewer's spent grain (BSG) is a by‐product of the brewing industry that contributes to a large volume of wastes. The lignocellulosic nature of this waste, together with presence of functional components such as antioxidants, represents an attractive for the composite's industry. In this work, BSG has been used as functional filler for polypropylene matrix to give an additional use to this industrial waste. Addition of BSG filler improves the overall environmental efficiency of the polypropylene matrix thus leading to high environmentally friendly materials. BSG can be loaded in the 10–40 wt% range with easy manufacturing, balanced mechanical properties, and additionally, excellent antioxidant properties are achieved with increasing BSG loading due to natural antioxidants that have not been removed during the brewing process. In particular, the onset of the thermo‐oxidative degradation of polypropylene is improved by 15–20°C for different compositions. Due to the lignocellulosic nature of BSG, water uptake is a clear drawback of PP–BSG composites but formulations containing 10‐30 wt% BSG hold the water uptake at very low values. POLYM. COMPOS., 38:40–47, 2017. © 2015 Society of Plastics Engineers

The State Space modelling approach has been recently proposed as an engineeringdriven technique for part quality prediction in Multistage Machining Processes (MMP). Current State Space models incorporate fixture and datum variations in the multi-stage variation propagation, without explicitly considering common operation variations such as machine-tool thermal distortions, cutting-tool wear, cutting-tool deflections, etc. This paper shows the limitations of the current State Space model through an experimental case study where the effect of the spindle thermal expansion, cutting-tool flank wear and locator errors are introduced. The paper also discusses the extension of the current State Space model to include operation variations and its potential benefits.