Melt Mass Flow Rate Research Articles

Development of Technologies for Processing Polypropylene Foil Waste and Their Use in the Production of Finished Products.

This work aims to assess the possibility of using packaging industry waste to modify polypropylene products (PPs). The products were made in the form of extruded foil and injected samples. The products were produced using regranulate made of polypropylene cast foil. Maleic anhydride-modified polypropylene (MAPP) and polyolefin elastomer (POE) with a glycidyl ester functional group were used to modify the polypropylene. The samples were produced based on 50% foil waste reground and 50% pure PP. The rheological properties of the blends were assessed using the melt mass flow rate (MFR) technique; thermal properties using the differential scanning calorimetry method (DSC). The products manufactured using the injection molding method were subjected to an analysis of mechanical properties, such as tensile strength and impact strength. Also, in the case of film samples, tensile strength was assessed. Color-change assessments with CIE L*a*b* were carried out for all materials. Injection-molded products based on recycled metallized cast foil showed favorable mechanical properties such as tensile strength (1 MAPP = 26.7 MPa; 2 MAPP = 27.1 MPa), which was higher than the original material (cPP = 20.7 MPa). Also, for the films produced from regrind, the tensile strength was at a level similar (1 MAPP = 24.6 MPa; 2 MAPP/POE = 25.1 MPa) to the films extruded from virgin materials (cPP = 24.9 MPa). The introduction of a POE additive to the blends resulted in increased impact strength (1 MAPP/POE = 31 kJ/mol; 2MAPP/POE = 18 kJ/mol; 3 MAPP/POE = 11 kJ/mol) in relation to unmodified samples (cPP = 7 kJ/mol). The introduction of a POE additive to the tested mixtures improved the impact strength of the injected products by almost 4 times for sample 1 MAPP/POE and 2.5 times for sample 2 MAPP/POE in comparison to virgin cPP. These studies confirmed that foil waste can be successfully used to modify polypropylene products shaped both in the injection and extrusion processes.

Effect of carbodiimides on the compatibility and hydrolytic behavior of PLA/PBAT blends

Blends of polylactic acid (PLA) and poly(butylene adipate-co-terephthalate) (PBAT) have great potential to replace conventional polyolefin and polyester materials. However, poor compatibility and fast degradation rate limit its development. In this paper, the effects of two monomer-type carbodiimides and one polymerized carbodiimide on the crystalline, thermal stability, hydrolysis properties, and mechanical properties of PLA/PBAT blends are investigated by Fourier transform infrared spectroscopy, scanning electron microscope, differential scanning calorimetry, thermogravimetric analysis, gel permeation chromatography, melt mass-flow rate, terminal carboxyl content, tensile properties, and rotational torque. It is found that all the three carbodiimide additives can improve the compatibility and enhance the mechanical, processing, and thermal stability properties of PLA/PBAT blends except for their reduced crystallization performance. Moreover, regarding the hydrolysis properties, the two monomeric carbodiimides exhibit little effect on the hydrolysis of PLA/PBAT blends, even accelerating the degradation rate under alkaline conditions. However, the antihydrolysis effect of polycarbodiimide is remarkable, which effectively improves the compatibility and antihydrolysis properties of PLA/PBAT blends.

Efficient Use of Secondary Raw Material from the Production of Polyamide Construction Products

This study aimed to assess the possibility of using post-production waste and the impact of the conditioning method on the mechanical and thermomechanical properties of polyamide injection molded parts. Samples containing 5, 10, and 15 wt.% of ground post-production waste were produced using injection molding technology. The rheological properties by oscillatory rheometry, the melt mass flow rate (MFR), and the thermal stability by thermogravimetric analysis (TGA) of polymer mixtures containing recycled fraction were determined. The samples were conditioned under the following conditions: 24 h and 14 days in distilled water, in a climatic chamber, and aged in a xenon-light-accelerated aging chamber. Then, the impact and static tensile strength and heat deflection temperature (HDT) were assessed. The results show that the addition of post-production waste in the form of grinding does not significantly affect the mechanical and thermomechanical properties of the finished products. This research provides valuable information regarding the possibility of using secondary materials for manufacturing high-performance construction products. Moreover, it was proven that the process of conditioning polyamide samples in a climatic chamber was the most effective and significantly increased the impact strength of the tested material.

Assessment of property profile of post‐industrial polypropylene recyclates through a multivariable recycling process

AbstractThis study provides key insights into the extrusion of a post‐industrial feedstock primarily composed of polypropylene (PP) and reveals its influence on the property profile of the recyclate. The objective of this study was to gain a fundamental understanding of complex process‐property relationships. Therefore, a two‐part experimental design was established. The first part aimed to analyze the feedstock variability by investigating key material properties of recyclates produced under constant processing conditions. The second part aimed to systematically evaluate the effect of the screw speed, filtration setup, and degassing setup on the properties of the recyclates. An industrial‐scale recycling extrusion line was used. The material evaluation included melt mass‐flow rate (MFR), ash content, oxidation induction temperature, tensile and impact properties, degassing performance, and residual volatile organic compounds (VOCs). Higher melt temperatures led to chain scission of the PP fraction, resulting in increased MFR and higher material stiffness. Additionally, a finer filtration positively contributed to the enhanced material stiffness. Furthermore, the mechanical properties were also influenced by the levels of inorganic fillers in the material composition of the feedstock. Finally, the filtration setup had a greater impact on degassing performance and residual VOC levels than the degassing setup and screw speed.

Effect of wood flour and compatibilizer content on the properties of wood-plastic composites

Wood-plastic composites (WPC) with are prepared by melting and mixing wood flour (WF) and thermoplastics which has green and biodegradable advantages and is of great significance in the development of the era of global resource scarcity. In this work, recycled polypropylene and WF were used as raw materials and commercially available maleic anhydride grafted polypropylene (MAH-g-PP) was used as a compatibilizer. The extrusion injection molding method was used and investigated by varying the amount of WF and compatibilizer added. The composites were analyzed for micro-morphology, melt mass flow rate, mechanical properties, and thermal stability by scanning electron microscopy (SEM), melt flow rate tester (MFR), electronic universal testing machine, and thermogravimetric analysis (TGA). According to the results, WF shows a positive effect in terms of storage and loss modulus of the composites, but it shows a negative effect in terms of thermal stability and mechanical properties. As an effective compatibilizer, MAH-g-PP plays an important role in improving the mechanical properties of the composites, especially at an additional level of 4 wt%, which maximized the overall performance of the composites.

Cascadic degradation of selected polyolefin grades in a simulated closed-loop recycling process

Reintroducing recycled plastics into production processes can lead to irreversible degradation and changes in their properties, thereby limiting their recycling potential to a finite number of loops. This study investigates the impact of process-induced degradation resulting from multiple reprocessing cycles on specific material properties and aims to establish structure–property relationships. Four different polyolefins, including two polypropylenes, high-density polyethylene, and low-density polyethylene, were selected for the study. The materials underwent extrusion, pelletizing, injection molding, and milling before being reintroduced into the reprocessing cycle. This sequence of processing steps was repeated six times on each material. Various characterization techniques, including high-temperature gel permeation chromatography, melt mass flow rate, parallel-plate rheology, differential scanning calorimetry, gas chromatography–mass spectrometry, and optical defect control system, were performed to evaluate the molecular structure, rheological behavior, thermal stability, and the resulting contaminants and defects after each reprocessing step. The reprocessing of polypropylene resulted in a gradual decrease in the average molecular weights accompanied by a shift to lower viscosities and higher melt mass flow rates, whereas the polyethylene grades showed the opposite trend with a less pronounced effect in high-density polyethylene. The volatile organic compounds rose in polypropylene and sank in polyethylene after reprocessing. Additionally, all four materials exhibited an increase in degradation-related defects based on optical defect analysis.Graphical abstract

Preparation, shape memory properties and application research of PLA/PCL‐based shape memory polymers doped with Al2O3 and lignin

AbstractIn this paper, the influence of different material trademarks, mass ratios, the melt mass‐flow rate (MMFR) and molecular weights (MW), mold and injection temperatures, Al2O3 powder and lignin on the shape memory properties of PLA/PCL SMP material (PPSM) were then analyzed in detail by different characteristic methods. Besides, three promising applications (Origami metamaterials and variable‐stiffness grippers) are provided utilizing the PPSM doped with Al2O3/lignin. Eventually, a compensating strategy was discussed to improve the final configuration of the SMP after multi‐cycles. The shape memory recovery ratios could be improved by increasing the MMFR of PLA and the MW of PCL. The addition of 2 g‐Al2O3 could shorten the recovery time, while the addition of 2 g‐lignin could increase the thermal‐recovery force and mechanical performance. The shape memory rate under 20 g weights, initial peak forces at room and high temperatures of the origami metamaterials could reach 57%, 2027.29 N and 17.49 N, respectively. The tensile force of banding rebars could reach 150.29 N, which is promising to apply into the construction field.

Investigation on close-coupled gas atomization for Fe-based amorphous powder production via simulation and industrial trials: Part I. Melt breakup behaviors during primary atomization

The primary atomization process is simulated by Volume of Fluid (VOF) model and dynamic adaptive mesh method. The influence of melt mass flow rate and atomization pressure on the breakup process is investigated, and the effect of hot gas atomization is also evaluated. The results show that the breakup is insufficient when the melt mass flow rate is larger than 0.075 kg s−1, while the liquid film breakup inducing the nozzle clogging occurs when the melt mass flow rate is too low (0.025 kg s−1). The backflow of droplets occurs at low atomization pressure (1.0 MPa), and various defects (satellite powders, hollow powders and needle-shaped powders) appear when the atomization pressure is larger than 3.0 MPa. Although the breakup efficiency can be significantly improved by increasing the gas temperature, severe deformation of the gas-liquid interface is induced due to the Kelvin–Helmholtz wave and gas-liquid interaction, easily leading to the formation of hollow powders. Besides, the gas-to-melt ratio (GMR) is identified as a simple criterion for predicting primary atomization breakup modes, with liquid film breakup occurring when GMR≥4.4 and "fountain" breakup occurring when GMR≤4.3. In this work, not only the gas-liquid interaction is systematically analyzed by establishing a flow-heat transfer-VOF coupling model, but also the GMR is proposed to predict the breakup mode in the industrial production, which can provide theoretical and methodological guidance for the optimization of atomization operational parameters.

Impact of Multiple Reprocessing on Properties of Polyhydroxybutyrate and Polypropylene.

Biobased plastics have the potential to be sustainable, but to explore their circularity further, current end-of-life options need to be broadened. Mechanical recycling is one of the most accepted methods to bring back plastics into the loop. Polyhydroxybutyrates (PHBs) are biobased and biodegradable in nature with promising properties and varied applications in the market. This study focuses on their potential for mechanical recycling by multiple extrusion cycles (E1-E5) and multi-faceted characterization of the virgin (V) and reprocessed materials from E1 to E5. The behavior is compared to polypropylene (PP) as a reference with a similar property profile, which has also been reprocessed five times. The thermal properties of both series showed a stable melting point and thermal decomposition temperature from thermal analyses (differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA)). However, a steady increase in the degree of crystallinity was observed which could counterbalance the decrease in molecular weight due to repeated extrusion measured by gel permeation chromatography and resulted in similar values of tensile strength across the cycles. The strain at break was impacted after the first extrusion, but no significant change was observed thereafter; the same was observed for impact strength. Even in scanning electron microscopy (SEM) images, virgin and E5 samples appeared similar, showing the stability of morphological characteristics. Fourier transform infrared spectroscopy (FTIR) results revealed that no new groups are being formed even on repeated processing. The deviation between the PHB and PP series was more predominant in the melt mass flow rate (MFR) and rheology studies. There was a drastic drop in the MFR values in PHB from virgin to E5, whereas not much difference was observed for PP throughout the cycles. This observation was corroborated by frequency sweeps conducted with the parallel plate method. The viscosity dropped from virgin to E1 and E2, but from E3 to E5 it presented similar values. This was in contrast to PP, where all the samples from virgin to E5 had the same values of viscosity. This paper highlights the possibilities of mechanical recycling of PHB and explains why future work with the addition of virgin material and other additives is an area to be explored.

Smart design choices provide new applications for recycled polypropylene: The case for tribology

Polypropylene (PP) is one of the most used polymers and has a wide scope of application, making it a key target for ambitious new recycling reforms. However, recycled PP is currently rarely used for technical applications. We investigated how reprocessing-induced mechanical and melt property changes restrict the scope of application of PP in open recycling loops, with deterioration of tensile properties and considerable increases in melt mass-flow rate consolidating regranulate use towards injection moulding applications. Remarkably, however, reprocessing had the opposite effect on tribological properties with changes to supramolecular structure reducing wear by up to one order of magnitude. As a proof-of-concept, this demonstrates how smart decisions on material flow during cycling could be a simple, effective, immediately implementable way to increase the scope of application, value and performance of recyclates without radical recycling industry reforms: changing the application of degrading reganulates after each cycle in favour of applications with different design requirements.

Investigation on close-coupled gas atomization for Fe-based amorphous powder production via simulation and industrial trials: Part II. Particle flight and cooling during secondary atomization

A two-way coupling Discrete Phase Model (DPM) is applied to calculate the secondary atomization process. The particle flight and cooling processes are studied under different process parameters. The results show that the average particle size (d50) depends on the gas-liquid interaction and decreases with increasing gas-to-melt ratio (GMR). The standard deviation of the particle size (d84/d50) increases as the melt mass flow rate increases, and both high and low atomization pressures result in a high d84/d50. The average cooling rate of particles can be improved by reducing the melt mass flow rate and increasing the atomization pressure. By increasing the gas temperature to 400 K, the d50 can be significantly reduced and the average cooling rate can be approximately increased two times, indicating that the hot gas atomization technique can effectively improve the yield of fine amorphous powders. However, excessive gas temperature not only has a limited effect on improving the cooling rate, but also significantly increases the d84/d50 and defective particles, suggesting that the gas temperature must be matched to the atomization process to achieve ideal effects. The powders produced at 2.0 MPa and 0.075 kg·s−1 exhibit good circularity with a d50 of 58.9 μm, which is in good agreement with the simulation analysis. Moreover, the powders with sizes less than 50 μm exhibit high amorphous fraction (96.6%) and outstanding soft magnetic properties. In this work, a flow-heat transfer-DPM coupling model is established to provide theoretical guidance for the production of high-performance Fe-based amorphous powders.

Bicomponent melt spinning of polyamide 6/carbon nanotube/carbon black filaments: Investigation of effect of melt mass-flow rate on electrical conductivity

Combining the several mixed phase structures and property profiles with a conductive, high aspect ratios nanofiller such as carbon nanotubes, graphene, and carbon black, specific morphological structures in melt spinning can be reached that offer much more potential for developing new functional fibers. Thus, understanding and controlling filler localization inside the developing phase morphology during melt spinning are the keys to the necessary structures. This work aimed to offer the possibility of producing fibers from electrically conductive polymer composites with a high filler concentration. First, the influence of different commercially available nanofillers, such as multi-wall carbon nanotubes (MWCNTs), graphene and carbon black on Polyamide 6 (PA6)-based nanocomposite melt-spun fibers were examined. Following the lab-scale melt spinning experiments, PA6/MWCNT-CB nanocomposite filaments containing 10 wt% nanofiller (each 5 wt%), were chosen for a pilot-scale bicomponent melt spinning process to investigate the influence of the nanocomposite core material feeding parameters on the properties of melt-spun fibers. The electrical conductivity decreased by half (from 3.13E-02 to 6.72E-03) when melt flow rate was increased from 3 g/min to 6 g/min. Scanning electron microscopy micrographs and thermal gravimetric analysis thermograms showed that the change in MFR values significantly affected the nanocomposite filaments’ surface properties.

Influence of a Multiple Epoxy Chain Extender on the Rheological Behavior, Crystallization, and Mechanical Properties of Polyglycolic Acid

This study investigated the impact of a multiple epoxy chain extender (ADR) on the rheological behavior, crystallization, and mechanical properties of polyglycolic acid (PGA). Tests of the torque and melt mass flow rate and dynamic rheological analysis were conducted to study the rheological behavior of PGA modified with ADR. The rheological results of the modified PGA showed a significantly increased viscosity and storage modulus with an increase in the ADR amount, which could be attributed to the chain extension/branching reactions between PGA and ADR. It was proved that ADR could be used as an efficient chain extender for tailoring the rheological performance of PGA. The Han plot of the modified PGA showed a transition of viscous behavior to elastic behavior, while the ADR content was increased from 0 to 0.9 phr. The formation of long-chain branches (LCBs) was confirmed via the Cole–Cole plot and weighted relaxation spectrum, wherein the LCBs substantially changed the rheological behavior of the modified PGA. The vGP plots predicted a star-type topological structure for the LCBs. The results of non-isothermal crystallization kinetics suggested that the crystallization of the modified PGA was predominantly homogeneous nucleation and three-dimensional growth. The crystallinity decreased slightly with the increase in the ADR amount. Compared to neat PGA, the modified PGA samples exhibited better tensile and flexural performances.

From Bottle Caps to Frisbee-A Case Study on Mechanical Recycling of Plastic Waste towards a Circular Economy.

This study demonstrates an open-loop recycling process of a specific post-consumer plastic waste stream. The targeted input waste material was defined as high-density polyethylene beverage bottle caps. Two methods of waste collection, informal and formal, were employed. Thereafter, materials were hand-sorted, shredded, regranulated, and then injection-molded into a flying disc (i.e., frisbee) as a pilot product. To observe the potential changes in the material throughout the entire recycling process, eight different test methods including melt mass-flow rate (MFR), differential scanning calorimetry (DSC), and mechanical tests were carried out on the various material states. The study showed that the informal collection led to a relatively higher purity in the input stream, which also appeared to have a 23% lower MFR value compared to that of the formally collected materials. The DSC measurements revealed a cross-contamination by polypropylene, which clearly affected the properties of all investigated materials. The cross-contamination led to a slightly higher tensile modulus in the recyclate, while the Charpy notched impact strength declined after processing by approximately 15% and 8% compared to those of the informal and formal input materials, respectively. All materials and the processing data were documented and stored online as a practical implementation of a digital product passport as a potential digital traceability tool. Furthermore, the suitability of the resulting recyclate to be used in transport packaging applications was also investigated. It was found that a direct replacement of virgin materials for this specific application is not possible without proper material modification.

Breakup process modeling and production of FeSiAl magnetic powders by close-coupled gas atomization

Close-coupled gas atomization is extensively used in the industrial production of alloy powders due to the advantages of high efficiency, low cost and excellent powder properties. In order to investigate the complex gas-liquid interaction during atomization, primary atomization was simulated through the VOF (Volume of Fluid) model and the dynamic adaptive mesh method, and a two-way coupling DPM (Discrete Particle Model) was used to simulate secondary atomization. The results showed that under the low melt mass flow rate of 0.0050 kg s−1, the flow separation and droplet backflow occurred at the atomization pressure of 1 MPa, while gas-liquid interfaces deformed and rotated drastically when the atomization pressure is above 3 MPa, which led to the formation of hollow powders. When the melt mass flow rate was 0.0150 kg s−1, the d50 decreased from 40.7 to 38.4 μm as the atomization pressure increased from 2 to 3 MPa. However, the chance of collision between particles increased due to the decrease in the spray cone angle, and both the standard deviation of particle size and atomization efficiency deteriorated, which indicated that 2 MPa was the optimum atomization pressure. As the mass flow rate increased from 0.0050 to 0.0150 kg s−1, the gas to melt ratio decreased, but the d50 only increased from 32.3 to 40.7 μm, indicating that the mass flow rate of 0.0150 kg s−1 did not significantly affect the particle size distribution, but also contributed to improve the production efficiency and avoided the risk of the nozzle freeze-off. The d50 of the spherical FeSiAl powders produced by the industrial tests at 2 MPa and 0.0150 kg s−1 was 44.7 ± 2.1 μm, which was basically consistent with the simulation results, indicating that the parameter optimization by the coupling model developed in this study could provide theoretical and practical guidance for the preparation of high-performance alloy powders by gas atomization.

Control of hydrolytic degradation of polyglycolic acid using chain extender and anti‐hydrolysis agent

AbstractBiodegradable polyglycolic acid (PGA) shows great potential to substitute engineering petrochemical‐based polymers because of its high mechanical strength, stiffness, and gas barrier. However, drawbacks such as low melt strength, poor thermal stability, and rapid degradation limited its practical applications. In this paper, PGA was modified by reactive extrusion using chain extender (CE) and anti‐hydrolysis agent (AHA). The effects of the modification on the flow properties, melt viscosity and long‐term hydrolysis behaviors of PGA were studied. Compared with the unmodified but one‐pass processed PGA (C‐PGA), the melt mass flow rate of modified PGA (M‐PGA) decreased, while the complex viscosity (ω = 0.1 rad/s) dramatically increased, attributable to the realization of effective chain extension. The accelerated hydrolysis aging test indicated that the hydrolysis rate constant of C‐PGA at 30°C was 0.06183 day−1, and that of M‐PGA was 0.01332 day−1, which exhibited a 78% reduction. Correspondingly, the service life of M‐PGA was significantly prolonged. This may expand the potential applications of PGA, such as packaging film, agriculture, or textiles.

INFLUENCE OF THE POURING DIRECTION ON THE QUALITY OF THE MELT ENTERING THE MOLD AND OBTAINING A GOOD STANDARD CAST IRON SAMPLE

The paper presents the results of computer simulation (on the example of grey cast iron of SCH 20 grade) of the influence of melt pouring direction on the degree of defects of shrinkage origin in the axial zone of the neck of a tensile sample when filling the mold cavity with a standard cast sample for optimal values of melt mass flow rate.

Evaluation of the Durability of PE-HD Geosynthetic Barriers Using High-Pressure Autoclave Tests

To evaluate the resistance of a 2 mm thick polymeric geosynthetic barrier (GBR-P) made of high-density polyethylene (PE-HD), oxidation tests at 80 °C using high-pressure autoclaves at three different oxygen pressures were carried out. After different times, 18 different evaluations were performed on the aged test specimens of the GBR-P. The following characteristics were considered: thermoanalytical methods like oxidation induction time (OIT), crystallinity and oxidation onset temperature (OOT), viscosity measurements like melt mass-flow rate (MFR) and viscosity, mechanical properties of the short term tensile test as well as stress crack resistance methods with the notched constant tensile load (NCTL) test and the strain hardening test (SHT). The failure times extrapolated to atmospheric conditions at the test temperature of 80 °C were in the range of 450–550 days for the stress crack tests. For the analytical methods, the failure times were 620–780 days and for the tests in the short-time tensile test, the failure times were between 700 and 900 days, depending on the property. To evaluate the OIT measurements, investigations were carried out on the influence of the sampling, preparation and treatment of the OIT measurement samples. Furthermore, the influence of oxidation on the thickness of the test samples was investigated. For this purpose, test specimens with thicknesses of 1 mm, 2 mm, 4 mm and 10 mm were produced and tested with the same material. The consumption of antioxidants on the surface of the test specimens was twice as high as inside the specimens. It was shown that a wide range of parameters is suitable for representing the ageing states of a PE-HD GBR-P. With very few exceptions, it was possible to determine the time transitions up to which the properties hardly changed and from which a steep rise or steep fall occurred. The most reliable and practicable test methods for ageing tests in the study were: elongation at break in the tensile test, the strain hardening modulus, OIT and OOT.

Influence of Different Types of Peroxides on the Long-Chain Branching of PP via Reactive Extrusion.

Long-chain branching (LCB) is known as a suitable method to increase the melt strength behavior of linear polypropylene (PP), which is a fundamental weakness of this material. This enables the modification of various properties of PP, which can then be used—in the case of PP recyclates—as a practical “upcycling” method. In this study, the effect of five different peroxides and their effectiveness in building LCB as well as the obtained mechanical properties were studied. A single screw extruder at different temperatures (180 and 240 °C) was used, and long-chain branched polypropylene (PP-LCB) was prepared via reactive extrusion by directly mixing the peroxides. The peroxides used were dimyristyl peroxydicarbonate (PODIC C126), tert-butylperoxy isopropylcarbonate (BIC), tert-Butylperoxy 2-ethylhexyl carbonate (BEC), tert-amylperoxy 2-ethylhexylcarbonate (AEC), and dilauroyl peroxide (LP), all with a concentration of 20 mmol/kg. The influence of the temperature on the competitive prevalent reactions of degradation and branching was documented via melt mass-flow rate (MFR), rheology measurements, and gel permeation chromatography (GPC). However, via extensional rheology, strain hardening could be observed in all cases and the mechanical properties could be maintained or even improved. Particularly, PODIC C126 and LP signaled a promising possibility for LCB in this study.

Influence of the Design Solutions of Extruder Screw Mixing Tip on Selected Properties of Wheat Bran-Polyethylene Biocomposite.

The study investigated the impact of the extruder screw design solution—the intensive mixing tip used—on the course of the extrusion process and the properties of the obtained biocomposite extrudate. A lignocellulosic wheat bran biocomposite based on a low-density polyethylene matrix was extruded. Three mixing tips of the screw were used interchangeably: apineapple tip, a cut rings tip, and a Maddock tip. The experimental tests carried out included the production of an extrudate with a mass content of bran altered within the range from 10% to 50%. Processing properties such as the melt flow rate (MFR) and mass flow rate of the extruded biocomposite were determined. Selected physical, mechanical, and structural properties of the biocomposite extrudate obtained with the use of the three tested mixing tips at five bran contents were tested.