Poly(lactic acid)-PLA is a polyester that can be produced from lactic acid derived from renewable resources. This polymer offers attracting uses in packaging industry due to its biodegradability and high tensile strength. However, PLA is quite brittle, which limits its applications. To overcome this drawback, PLA was plasticized with epoxy-type plasticizer derived from a fatty acid, octyl epoxy stearate (OES) at different loading (1, 3, 5, 10, 15 and 20 phr). The addition of OES decreases the glass transition temperature and provides a remarkable increase in elongation at break and impact absorbed energy.Plasticizer saturation occurs at relatively low concentrations of about 5 phr OES; higher concentration leads to phase separation as observed by field emission scanning electron microscopy (FESEM). Optimum balanced mechanical properties are obtained at relatively low concentrations of OES (5 phr) thus indicating the usefulness of this material as environmentally friendly plasticizer for PLA industrial formulations.

Ternary blends of poly(lactic acid) (PLA), poly(3-hydroxybutyrate) (PHB) and poly(ε-caprolactone) (PCL) with a constant weight percentage of 60%, 10% and 30% respectively were compatibilized with soybean oil derivatives epoxidized soybean oil (ESO), maleinized soybean oil (MSO) and acrylated epoxidized soybean oil (AESO). The potential compatibilization effects of the soybean oil-derivatives was characterized in terms of mechanical, thermal and thermomechanical properties. The effects on morphology were studied by field emission scanning electron microscopy (FESEM). All three soybean oil-based compatibilizers led to a noticeable increase in toughness with a remarkable improvement in elongation at break. On the other hand, both the tensile modulus and strength decreased, but in a lower extent to a typical plasticization effect. Although phase separation occurred, all three soybean oil derivatives led somewhat to compatibilization through reaction between terminal hydroxyl groups in all three biopolyesters (PLA, PHB and PCL) and the readily reactive groups in the soybean oil derivatives, that is, epoxy, maleic anhydride and acrylic/epoxy functionalities. In particular, the addition of 5 parts per hundred parts of the blend (phr) of ESO gave the maximum elongation at break while the same amount of MSO and AESO gave the maximum toughness, measured through Charpy’s impact tests. In general, the herein-developed materials widen the potential of ternary PLA formulations by a cost effective blending method with PHB and PCL and compatibilization with vegetable oil-based additives.

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The compensation of an electrical system from passive compensators mainly focuses on linear systems where the consumption of charges does not vary significantly over time. In three-phase three-wire systems, when the network voltages are unbalanced, negative-sequence voltages and currents appear, which can significantly increase the total apparent power supplied by the network. This also increases the network losses. This paper presents a method for calculating the compensation of the positive-sequence reactive power and unbalanced powers caused by the negative-sequence line currents using reactive elements (coils and/or capacitors). The compensation is applied to three-phase three-wire linear systems with unbalanced voltages and loads, which are connected to an infinite power network. The method is independent of the load characteristics, where only the line-to-line voltages and line currents, at the point where compensation is desired, need to be known in advance. The solution obtained is optimal, and the system observed from the network behaves as one that only consumes the active power required by a load with a fully balanced current system. To understand the proposed method and demonstrate its validity, a case study of a three-phase three-wire linear system connected to an infinite power network with unbalanced voltages and currents is conducted.Appl. Sci. 2020, 10, 113 2 of 17 these inefficient powers. According to [13,14], imbalances at one point in the system can help offset some of the imbalances at another point. Such situations cannot be analyzed if only the modules of voltages and currents are known.The application of electronics, in the compensation of electrical systems, indicates that most industries today mainly focus on the use of active compensators. The advantages of these compensators or filters cannot be denied, especially for the compensation of non-linear systems. As compared to passive compensators, the active compensators are more expensive, less robust, and consume more energy. In certain situations, for linear systems, where the load does not vary with time, the use of passive compensators is a good alternative. They are configured from reactive elements (coils and/or capacitors). In this study, passive compensators are used to compensate for the reactive and unbalanced power resulting from the negative-sequence current of any three-wire system.The concept of compensation of an electrical system by passive compensators is not new. Steinmetz [15] developed a passive compensator to obtain a system of balanced line currents. He used a single-phase load with known data, and compensated it with a coil and capacitor and we believe that the voltages in the study were balanced. This study has been extended by many authors [16][17][18][19][20][21][22][23][24].Gyugyi et al.[25] studied compensation through passive compensators for a three-wire linear system with unbalanced load and balanced voltages. For this purpose, they categorised the line currents into symmetric component values, and proposed...

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.