Investigation of the Orientational Mechanical Properties of Biodegradable Extrusion Films Based on Polyolefins and Beet Pulp

The article discusses the possibility of obtaining biodegradable films based on polyolefins and beet pulp by the extrusion method. Biodegradable composites of two mixes with 15% and 25% beet pulp content have been obtained. Compounding was carried out on a twin-screw extruder, and then samples of biodegradable films were obtained by cast film extrusion. The influence of the vegetable filler particles’ orientation on the composites mechanical properties has been studied. It has been shown that composites mechanical properties significantly increase in the direction of polymer melt stretching.

Effect of different extrusion methods on physicochemical properties and qualities of noodles based on rice flour

Rice noodles have been manufactured in the food industry using different extrusion methods, such as traditional and modern extrusions, which affect the noodle structure and qualities. Therefore, the effects of the extrusion process on qualities of rice noodles using the same blend of rice flour and crosslinked starch were evaluated. In this study, a capillary rheometer was used as an alternative approach to simulate the traditional extrusion method in which the noodles are obtained by continuously pressing the pregelatinized noodle dough through a die. For modern extrusion, a twin-screw extruder was employed to obtain the noodles in a one-step process. The optimal range of moisture content used in the formulation was studied. Upon cooking, the noodles showed a decrease in cooking time and cooking loss with increasing moisture content in the formulation. All cooked noodles showed comparable tensile strength, but those extruded by a twin-screw extruder had substantially greater elongation. Scanning electron micrographs revealed that the noodles prepared using the extruder had a denser starch matrix, while those obtained from a capillary rheometer showed the aggregation of starch fragments relevant to the existence of starch gelatinization endotherm from differential scanning calorimetry. This indicated that the extrusion process using the twin-screw extruder provided a more uniform starch transformation, i.e., more starch granule disruption and gelatinization, thus giving the noodles a more coherent structure and better extensibility after cooking. The obtained results suggested that different thermomechanical processes used in the noodle industry gave the extruded rice noodles different qualities respective to their different microstructures.

Metamorphosis of Twin Screw Extruder-Based Granulation Technology: Applications Focusing on Its Impact on Conventional Granulation Technology

In order to be at pace with the market requirements of solid dosage forms and regulatory standards, a transformation towards systematic processing using continuous manufacturing (CM) and automated model-based control is being thought through for its fundamental advantages over conventional batch manufacturing. CM eliminates the key gaps through the integration of various processes while preserving quality attributes via the use of process analytical technology (PAT). The twin screw extruder (TSE) is one such equipment adopted by the pharmaceutical industry as a substitute for the traditional batch granulation process. Various types of granulation techniques using twin screw extrusion technology have been explored in the article. Furthermore, individual components of a TSE and their conjugation with PAT tools and the advancements and applications in the field of nutraceuticals and nanotechnology have also been discussed. Thus, the future of granulation lies on the shoulders of continuous TSE, where it can be coupled with computational mathematical studies to mitigate its complications.

Influence of geometric parameters of screw nozzles of twin-screw extruder-press on oil yield

In modern economic conditions, the chosen technology of raw material processing and the choice of the necessary equipment for both the line as a whole and the oil press are of great importance in oil production. In small-capacity workshops, screw presses of various designs are used. The twin-screw extruder occupied a certain niche among the press equipment with a productivity of 150–500 kg/h. Their use can significantly simplify the technology of oilseed processing. They combine operations of heat treatment, grinding, and pressing of vegetable oil. It is important to study the influence of geometric parameters of the oil pressure path and screw nozzle on the oil yield. In twin-screw extruders, it is rational to choose the pitch of the worm, the width of the channel between the turns, the width of the crest of the turn and the length of the nozzle with variable geometrical parameters. The analysis and selection of geometrical parameters of working bodies of a twin-screw extruder on the basis of theoretical calculations are carried out. Two sets of experimental working bodies with the changed geometrical parameters are made. Their theoretical degree of compression is determined, which is 5.50, 4.69, and 4.33, respectively. It is experimentally confirmed that the oil yield depends on the degree of compression due to the geometric parameters of the screw. The effect of a sharp drop in the free volume of the screw on the energy performance and press extruder performance has been revealed. The general nature of the change in the free volume in the areas of nozzle groups is accompanied by an uneven decrease of 40–80% towards the release of oil cake. The nature of the change in the free volume of turns along the length of the screw shaft characterizes the correctness of its design. The selection of rational geometric parameters of the working bodies should be considered in combination with other design parameters, which will intensify the process of oil pressing.

Investigation of the Thermal and Hydrolytic Degradation of Polylactide during Autoclave Foaming

Polylactide (PLA) is one of the most important bioplastics worldwide and thus represents a good potential substitute for bead foams made of the fossil-based Polystyrene (PS). However, foaming of PLA comes with a few challenges. One disadvantage of commercially available PLA is its low melt strength and elongation properties, which play an important role in foaming. As a polyester, PLA is also very sensitive to thermal and hydrolytic degradation. Possibilities to overcome these disadvantages can be found in literature, but improving the properties for foaming of PLA as well as the degradation behavior during foaming have not been investigated yet. In this study, reactive extrusion on a twin-screw extruder is used to modify PLA in order to increase the melt strength and to protect it against thermal degradation and hydrolysis. PLA foams are produced in an already known process from the literature and the influence of the modifiers on the properties is estimated. The results show that it is possible to enhance the foaming properties of PLA and to protect it against hydrolysis at the same time.