Plastic Components Research Articles

New geometry-inspired numerical convex analysis method for yield functions under isotropic and anisotropic hardenings

Convexity of a yield function must be guaranteed to ensure unique relationship between plastic strain increments and stress components. A geometry-inspired numerical convex analysis (GINCA) approach is developed to analyze the convexity of a yield function. The numerical approach is verified by the computation of convex domains for several typical yield functions of Drucker, Cazacu-Barlat2004, Hu2017, Cazacu2018 and a newly proposed function for differential-anisotropic hardening. The verified GINCA is applied to analyze the convexity of the Gao2011 yield function since it was not determined yet. The numerical approach is also used to determine the convex domain evolution with respect to plastic deformation in an anisotropic hardening function. It is also applied to investigate the convexity of polynomial yield functions for strong anisotropic metals. The result shows that the GINCA can effectively and correctly compute the convex domain for different yield functions. Besides, the numerical approach only needs to compute the effective stress from a yield function without any computation of the first- and second-order partial derivatives, compared to the complicated convex analysis by the Hessian matrix. Therefore, the proposed GINCA is user-friendly, effective and accurate to analyze the convexity of a yield function both for isotropic hardening and anisotropic/differential hardening. The Matlab codes are shared as electric attachments for scientists and engineers to check the convexity of a yield surface under biaxial loading, plane stress with shear stress and triaxial loading conditions.

Weld-line strength prediction for glass fiber reinforced polyamide-6 material through integrative simulation and its experimental validation

Injection molding is one of the preliminary production methods for plastic components. Typically, injection molding Moldflow simulations predicts potential issues like air void, weld-line, warpage etc. This work focuses on weld-line defect, which occurs when two or more flow fronts are meets each other during filling of the cavity. Most of the commercial algorithms are based on isotropic and homogeneous material assumptions however plastic materials are anisotropic and heterogeneous in nature. Therefore, accuracy with isotropic solvers may vary with actual reality. To consider material anisotropy and heterogeneous nature of the material, an integrative simulation is advantageous technology which gives more realistic results. A unique approach of integrative simulations has been used in this work to predict the strength of the weld-line as there is no direct standard procedure or software available to get weld-line strength. Moldflow simulation is performed on specially designed plaque wherein the weld-line is reproduced considering 30% glass-filled polyamide-6 material. The new material model is developed by mapping the structural model of tensile specimens on the Moldflow simulated plaque with integrative mapping approach. The mapped model considers fiber orientation and weld-line characteristics of the material which is then solved in the Abaqus structural solver. Experimental validation is performed by manufacturing of weld-line plaques, specimen preparation, and experimental testing. The results correlation is done for an isotropic and anisotropic material model with experimental results. The correlation study shows, a significant difference in results for isotropic simulation and integrative anisotropic simulations. The failure pattern and load-displacement behavior of integrative simulation is close match with experimental results with minimum 93% accuracy.

Novel experimental technique to model impression piles in centrifuge testing

A novel experimental technology for small-scale centrifuge tests on piled foundations has been investigated. The technology is suitable for bored piles where the pile shaft has been profiled to improve bearing capacity, such as with the impression pile which has an enhanced shaft capacity owing to the small impressions created along the shaft. In previous centrifuge testing, impression piles have been created by pouring resin into a profiled bore. However, in the technique described, a pile made from three-dimensionally (3D)-printed rigid plastic components with a mandrel mechanism is used to create a nodular shaft surface during model making. Once assembled the pile has the same geometry as the cast-in-situ impression pile. 3D-printed plastic piles allow for fast model making and demonstrate excellent repeatability. Because of the ductile behaviour of the soil–plastic interface the impressions improve the performance of a pile over the entire load settlement curve, not just at ultimate capacity. In addition, a greater increase in ultimate capacity was registered for the 3D-printed plastic impression piles compared to similar resin impression piles. At working load, the 3D-printed plastic impression piles outperformed traditional straight-shafted piles by 90%.

Multiprocess additive manufacturing via fused deposition modeling, chemical deposition, and electroplating with tough interfacial adhesion

Multiprocess additive manufacturing (MPAM) unlocks new materials and design spaces where multimaterial components consisting of polymers, metals, and ceramics can be produced as one consolidated part. MPAM enables state-of-the-art 3D-printed electronics and devices with embedded functionality by combining fused deposition modeling with chemical deposition and electroplating processes. However, the metalized plastic devices produced by these processes have a short lifespan because of their poor structural integrity due to the low adhesion at the metal–polymer interface. In this study, we elaborated on the adhesion mechanism at the 3D-printed metal–polymer interface and identified the MPAM factors that elevated significantly the integrity of metalized plastic components. The effects of the 3D-printed surface texture and surface treatment on the adhesion strength of copper plated on acrylonitrile–butadiene–styrene parts were analyzed. We found that a certain 3D-printed topography modified by quick acid etching created a hierarchically structured interface with superimposed macroscale, microscale, and nanoscale roughness that symbiotically improved the metal–polymer adhesion. These results have practical implications for automated equipment manufacturers and the electronic industry adapting MPAM for the 3D printing of multimaterial components and devices with embedded functionality.

Features of application in critical structures of products made by fused deposition using 3D printing technology

The technology of hot-melt 3D printing has prospects for military equipment and other special applications, provided that necessary requirements for the quality, strength and durability of plastic components are met. However, there is a problem of insufficient accuracy and unexplored patterns of change in technological parameters during 3D printing, which makes it necessary to manufacture critical structures using plasma deposition technology. The main purpose of the article is to study and evaluate the features of using the fused deposition method in 3D printing technology for the manufacture of products that are critical special-purpose structures and require increased strength and durability. To achieve this purpose, the technology and means of 3D printing by fused deposition method (filament feed control system with a circular encoder) have been improved. It has been established that the use of the filament feed control system can reduce the number of visually detected defects on the surface of printed products by an average of 71.7%, but increase the amount of wire consumed by 13% and the average printing time by 15-17%, which is due to the lack of supporting structures for the resulting surfaces. The research conducted in this paper has shown an increase in delamination strength of elements of critical structures, such as brackets for mounting a laser rangefinder to the body of an unmanned aerial vehicle. With the help of the filament feed control system, the strength of these elements has increased from 27.4 (tensile) and 32.1 (compressive) to 38 (tensile) and 44.3 MPa (compressive). There is also a more than 2.7-fold increase in the number of dynamic load cycles during endurance tests. This study indicates greater dynamic stability and less fatigue of the elements manufactured by fused 3D printing using a filament feed control system. The results will have practical applications in various fields, including military applications

A Small-Deformation Rate-Independent Continuous-Flow Model for Elasto-Plastic Frames Allowing Rapid Fatigue Predictions in Metallic Structures

Fatigue analysis in metallic frame structures can be challenging due to associated computational costs; if localized plasticity is involved, then the approach of three-dimensional (3D) continuum plasticity models for direct computation of stresses will be infeasible for the analysis of cyclic loading that would need to be modeled in medium- to high-cycle fatigue and vibratory fatigue applications. This difficulty is particularly accentuated in architected structures, for which high-resolution 3D finite element analysis (FEA) would be prohibitively expensive. In this work, we propose an alternative approach based on the use of novel elasto-plastic frame model with continuous flow (i.e. no sharp yield function) for modeling 3D frame and lattice structures. Rather than splitting the strains (as is done in classical plasticity) we split the deformation measures, extension, curvature and twist, into elastic and plastic components and postulate a rate type evolution rule for the plastic variables in terms of the stress resultants (axial force, bending moment, and torque). The combination of structural models together with the use of elasto-plastic operator split to solve the resulting boundary value problem allows for much faster determination of localized plasticity than continuum models can provide. The use of a continuous transition from elastic to rate-independent plasticity (as opposed to an abrupt change with classical plasticity models) allows us to capture localized microplasticity and determine resulting fatigue progression using a cycle-count-free, plastic work-based approach, formulated in terms of the curvatures and resultants. We demonstrate that (a) the model is able able to reproduce the response of 3D FEA with very few elements and (b) the model has the ability to rapidly predict the fatigue life under variable amplitude combined loading with relatively few frame elements.

Environmental assessment of several scenarios of active and passive radon control measures

In buildings, radon gas mainly enters through cracks in the floors and gaps around pipes and cables in contact with the soil, thereby increasing indoor radon levels. Like other building components or systems, the radon control measures have embodied and operational environmental impacts that have been neglected to a certain extent. While many actions have been taken recently to achieve carbon-neutral yet energy-efficient buildings, even radon control measures should be investigated not only for protecting human health since radon gas is the major source of ionising radiation for humans but also for the environment. This paper aims to undertake a comparative analysis of the embodied and operational impacts of variant radon-protective measures installed at the floor foundation level (both active and passive solutions) for new and existing buildings. In particular, this analysis includes four different measures based on radon venting from i) floor air gap created from plastic components, ii) flexible perforated pipes embedded in the gravel layer under the floor, iii) radon sump placed in the sub-floor layer, and iv) perforated tubes drilled horizontally into the subsoil under the house. In all cases, radon will be removed through a vertical exhaust pipe terminated above the roof or by a roof fan. The impacts are calculated for the life cycle assessment (LCA) stages A1-A3 (production phase) and B6 (operational energy) to determine whether future research should be focused on the reduction of environmental impacts on the production stages or the operational ones.

Pyrolysis of model plastic component polypropylene to hydrogen over mesoporous alumina catalysts: Effect of pluronic structure directing agents

Catalytic pyrolysis of the large and complex polymeric structure of plastic to gaseous fuel has been investigated in this work. A two-stage pyrolytic system is reported for cracking model waste plastic, polypropylene, over mesoporous alumina catalyst to produce H2 and CH4. The experiments have been conducted in the temperature range of 750–900 °C and various catalyst-to-plastic ratios under atmospheric pressure. The alumina-based catalysts were synthesized via the one-pot evaporation-induced self-assembly (EISA) method using four different structure-directing agents (SDA) namely PEG-1000, PEG-4000, P123, and F127 to understand the effect on catalytic properties and performance evaluation. Results revealed that the structured directing agents improve the catalyst's surface properties and affect the product yield. All synthesized catalysts were characterized for crystallinity, topography, and surface properties using X-ray diffraction analysis (XRD), Scanning Electron Microscope (SEM), Brunauer–Emmett–Teller (BET), Pyridine-Transmission Fourier transform infrared (Py-FTIR) spectroscopy, and atomic force microscopy (AFM) analysis. A significant effect of SDA was observed on the surface area of the synthesized mesoporous alumina (SMA) catalyst. The decreasing order in terms of the surface area of the SMA is SMAF127 >SMAP40 >SMAP123 >SMAP10> Alumina (without SDA). Approximately, a tenfold increase in surface area was observed with SMAF127 (mesoporous alumina) compared to non-mesoporous alumina. A maximum yield of hydrogen∼40.79 mmol/gram polypropylene was obtained with a catalyst-plastic (C/P) ratio of 1:2.5 at a temperature of 900 °C using SMAF127 owing to its high surface area, and other physiochemical properties.

Utilizing Fourier Transform Infrared Spectroscopy for Plastics Failure Analysis

Abstract This article explores one of the most commonly used analytical techniques in plastic component failure analysis—Fourier transform infrared spectroscopy—along with a case study to demonstrate its use.

Contacting of inserts with the integrated metal/plastic injection moulding

AbstractThe integrated metal/plastic injection moulding enables the production of plastics components with integrated conductor tracks and contacted inserts using an injection moulding machine. For this purpose, first a plastics carrier, which contains a groove for the later conductor track, is injection moulded and following electrical inserts are placed along the groove. The conductor track is then die‐casted from metallic solder. By using thermally conductive plastics, heat generated along the conductive paths and at the electrical inserts can be dissipated. A mechanical, electrical and optical characterisation of the material composite consisting of plastics carrier, metallic conductor track and electrical insert is carried out. In addition, process and material parameters that have an influence on the contacting of electrical inserts in connection with thermally conductive plastics in the integrated metal/plastic injection moulding are analysed. The results show that through the use of thermally conductive plastics, significant advantages in terms of heat dissipation and contact quality between the insert and the conductor track can be achieved.

Dual-Band Nested Circularly Polarized Antenna Array for 5G Automotive Satellite Communications

Currently, 5G low-earth orbit satellite communications offer enhanced wireless coverage beyond the reach of 5G terrestrial networks, with important implications, particularly for automated and connected vehicles. Such wireless automotive mass-market applications demand well-designed compact user equipment antenna terminals offering non-terrestrial jointly with terrestrial communications. The antenna should be low-profile, conformal, and meet specific parameter values for gain and operational frequency bandwidth, tailored to the intended applications, in line with the aesthetic design requirements of passenger cars. This work presents an original concept for a dual-band nested circularly polarized automotive user terminal that operates at the S-band frequencies around 3.5 GHz and Ka-band frequencies around 28 GHz, namely within the 5G new-radio bands n78 and n257, respectively. The proposed terminal is designed to be integrated into the plastic components of a passenger vehicle. The arrays consist of 2 × 2 aperture-coupled corner-truncated microstrip slot patch antenna elements for the n78 band and of 4 × 4 single-layer edge-truncated microstrip circular slot patch antenna elements for the n257 band. The embedded arrays offer, across the two bands, respectively, 9.9 and 13.7 dBi measured realized gain and 3-dB axial ratio bandwidths of 100 and 1500 MHz for the n78 and n257 bands along the broadside direction. Detailed link budget calculations anticipate uplink data rates of 21 and 6 Mbit/s, respectively, deeming it suitable for various automotive mobility and Internet-of-Things applications.

Rapid tooling of composite aluminium filled epoxy mould for injection moulding of polypropylene parts with small protruded features

Abstract Rapid tooling evolved from rapid prototyping is a novel method for developing prototype tooling rapidly using various additive manufacturing techniques. Traditional injection moulding is unsuitable for low-volume production because of the high initial cost. This study is focused on a rapid tooling approach for producing an injection mould insert for the low-volume production of plastic components. A plastic injection mould insert is designed, developed using composite aluminium filled epoxy with minute protruded features and tested on a vertical injection moulding machine as a rapid tool for low-volume production of plastic components. The composite aluminium filled epoxy (CAFE) mould insert is prepared using a wax master from silicon rubber mould prepared using a stereolithography master. Experiments are performed to determine the optimum mixing ratio of epoxy: aluminium powder for making the composite aluminium filled epoxy injection mould. The mould insert prepared was tested for the injection of polypropylene components on a vertical injection moulding machine and analyzed for dimensional accuracy. The analysis of dimensional accuracy and viability of minute features on the injected parts shows promising results for up to 30 injected parts. The injection of parts after 30 pieces resulted in increasing mould erosion and pitting, causing mould damage at the 36th injection shot. The experimental finding supports the feasibility of using the composite aluminium filled epoxy injection mould for low-volume production of the parts; however, the surface finish is inferior. The life of the mould is expected to give better results with a higher surface finish. It is also exposed that using mould release agents improves the life of the composite aluminium-filled epoxy injection mould.

Potential For Recycling Single-Use Plastic Waste - Case Study in Can Tho City, Vietnam

Circular economy is an economic ideal that has been concretized by the Vietnamese Government in the Law on Environmental Protection 2020. As a part of this model, plastic waste reuse and recycling are encouraged to extend the product life cycle. This study investigates the composition of recyclable plastic waste within the domestic waste sources in Can Tho city. The wastes were collected at waste gathering places, residential areas, markets, bus stations, and schools in the urban district of Ninh Kieu and suburban district of Cai Rang in Can Tho city. The results show that disposable plastic items are very diverse such as grocery bags, plastic bags, foam boxes, straws, drinking water bottles, etc. Plastic components accounted from 6.82 % in Cai Rang district to 14.89 % in Ninh Kieu district of the total waste. In which, LDPE plastic was the highest with 38.17 %, HDPE plastic and PETE plastic accounted for 20.81% and 4.89 %, respectively. Particularly, PETE is less found than other plastics as it is collected by scrap person at the disposal sources or by sanitation worker at the waste gathering place. PETE and HDPE plastics are completely recyclable, accounting for 25.70 %. In addition, LDPE plastic is also recyclable (38.17%) compared to other components. Thus, the recyclable plastic ratio of PETE, HDPE, and LDPE reaches 63.88 %. Meanwhile, non-recyclable plastics, accounted for 36.12 %, such as PS plastic (14.18 %), PP plastic (9.83 %) and other plastics (12.12 %). From the results, the amount of recyclable plastic discarded into the environment is nearly twice that of non-recyclable plastic. The potential to utilize recyclable plastics will most likely fit the circular economy model, which will both extend the product life cycle while limiting waste generation and minimizing adverse environmental impacts.

Optimisation of process parameters for dimensional stability in FDM

The fused deposition modelling (FDM) technique has been adopted in the present work to fabricate Acrylonitrile Butadiene Styrene (ABS) plastic components using input variables like layer thickness, orientation, infill rate and the number of shells. The dimensional geometrical changes of FDM printed built parts, that is, length, width and thickness variation, are optimised individually. Still, a confounding effect is found in the optimisation of individual responses. To overcome this issue, this study uses a fuzzy inference system as an artificially intelligent system. A fuzzy inference system transformed all the responses into one response, known as a multi-response performance index (MPI), and optimised the MPI coupled with Taguchi philosophy. The optimal parameter combination of FDM-printed ABS components for the slightest variation in length, width, and thickness was found to be layer thickness: 200 µm, orientation: 0°, infill rate: 20%,and the number of shells: 3. The significant parametric effect on the responses of FDM components was studied using analysis of variance, and the results reveal that orientation is the most influential parameter trailed by infill rate and the number of shells.

Tribological Characterisation and Modelling for the Fused Deposition Modelling of Polymeric Structures under Lubrication Conditions.

In recent years, additive manufacturing technology, particularly in plastic component fabrication, has gained prominence. However, fundamental modelling of the influence of materials like ABS, PC, and PLA on tribological properties in fused deposition modeling (FDM) remains scarce, particularly in non-lubricated, oil-lubricated, and grease-lubricated modes. This experimental study systematically investigates the effects of material type, lubrication method, layer thickness, and infill density on FDM component tribology. A tribology analysis is conducted using a TRB3 tribometer. The results indicate a coefficient of friction (CoF) range between 0.04 and 0.2, generally increasing and decreasing with layer thickness and filler density. The lubrication impact hinges on the material surface texture. The study models the intricate relationships between these variables via full-factor analysis, showing a strong alignment between the modelled and measured friction coefficients (an average error of 3.83%). Validation tests on different materials affirm the model's reliability and applicability.

Assessment of alkylphenols migration from packaging to fruit juices: Influential factors and health risks

Migration of plastic components or additives from packaging materials to food poses a potential health risk to humans. Alkylphenols, including 4-Nonylphenol and 4-tert-Octylphenol, are classified among the endocrine disrupting chemicals which exhibit estrogenic properties. One of the predominant pathways of human exposure to Alkylphenols primarily involves the ingestion of food and beverages, which have contaminated to Alkylphenols through leaching from the packaging materials. The objective of this study was to examine the presence of 4-Nonylphenol and 4-tert-Octylphenol compounds in various juice samples packed in Polyethylene terephthalate bottles and multilayer Tetrapack containers. Additionally, an evaluation was conducted regarding the influence of the expiration period and the two flavor of fruit juice (sour cherry and pineapple) on the leakage rate of alkylphenols. Health risk from exposure to alkylphenols through drinking packaged fruit juices was also estimated. 4-Nonylphenol and 4-tert-Octylphenol were detected in 100% of the samples at concentrations from 158.8 ng/L to 7604.2 ng/L and from 4.1 ng/L to 1373.8 ng/L, respectively. The results showed that over time, the concentration of contaminants in packaged fruit juices significantly increased. Fruit juices with a sour flavor, with a more acidic pH, typically tend to have a higher concentration of contaminants. Furthermore, the average concentration for both flavors was higher in polyethylene terephthalate packaging compared to Tetrapack. The risk assessment revealed that the group of children under 18 years of age is at a higher risk of health issues compared to the adult group due to exposure to alkylphenols found in packaged fruit juices.

Experimental Evaluation of New-Generation Waste Material as a Substitute in M-50 Concrete Mixes

The journey of concrete began around 600 BC, when the ancient Romans began widely using concrete for construction by mixing volcanic ash, lime, and seawater. Centuries later, it was in 1824 that Joseph Aspdin invented Portland cement by burning finely crushed chalk and clay until the carbon dioxide was eliminated. Between 1850 and 1880, Francois Coignet used Portland cement extensively for the first time in the construction of homes in England and France [17]. Since then, though there have been vast innovative leaps, improvements and inventions in the material used in construction, the construction industry is still heavily reliant on Portland cement and aggregates. This excessive use and mass dependence on concrete is now a concern for the construction industry as the natural resources used in concrete like sand and gravel are slowly being depleted. In addition, the environmental concerns relating to CO2 emissions from concrete have forced the industry to start looking for alternatives for the ingredients used in concrete.
 On the other hand, electronic waste, also known as electronic waste, is considered one of the harmful types of electronic waste in today’s new age world. Drinking water supplies are becoming polluted, and the environment and ecosystems are being impacted all around the world as a result of the unceasing increase of these technological wastes. Both of these current environmental issues can be mitigated to some extent by experimenting with and utilizing electronic waste materials in the construction industry. Along with traditional aggregate alternatives such as fly ash and rice husk ash, the industry is now experimenting with E-waste to determine if it can be a viable material for improving concrete strength and longevity.
 The primary objective of this research is to better understand the behavior of M-50 grade high strength concrete when coarse aggregate is replaced by E-waste plastics in staggered percentages. The strength of concrete containing E-waste plastic was tested at different time intervals after coarse aggregates were replacement with varying percentages of E-plastic waste by the volume range from 0 to 30 percentage. When compared to normal concrete, concrete with E-waste had comparable compressive, flexural, and tensile strength for 28 days up to a specified percentage of replacement. When the E-waste plastic component percentage is considerably high, however, there is a decline in strength after a certain point

Occurrence of micro- nanoplastics in a commercial recirculated aquaculture system and their translocation to cultured fish organs: A baseline study

Micro- and nanoplastics (MNPs; < 5 mm and < 1 µm, respectively), are contaminants of emerging concern representing a major part of global plastic pollution, due to their ubiquity both in natural and urbanised environments. Although environmental concentrations of these pollutants have been measured in a variety of matrices, information on the occurrence of MNPs in recirculated aquaculture system (RAS) farms, is scarce. The present study aimed to investigate the presence of MNPs in a commercial European RAS farm, by identifying the occurring polymers in both the system water and in a variety of fish tissues and quantifying their concentration. To this end, adult Oreochromis niloticus (Nile tilapia) were sampled for brain, liver, gut, stomach, muscle and gonads, and water was collected from both the influent and the effluent of the system. Size exclusion chromatography coupled to high resolution mass spectrometry equipped with an atmospheric photoionization source was employed to identify five distinct polymers, namely polyethylene (PE), polyisoprene (PI), polysiloxane, perhydropolysilazane (PHPS), and poly-dimethylsiloxane (PDMS). Two polymers were present in the system water, with PI being found at considerably greater concentrations in the effluent than in the influent. By order, the tissues that retained the greater number of polymers were: muscle > gut = brain > stomach > liver = gonads. The analyses indicated that liver and gonads did not contain any MNPs particles, whereas muscular tissue contained up to 3 distinct compounds. The results may reflect different uptake pathways of MPNs depending on the polymer type and its respective properties. The presence of these emergent contaminants in the muscle represents an additional exposure pathway for humans, through the ingestion of contaminated RAS-farmed fish, adding to the long list of confirmed exposure routes. Investigating the input of MNPs in RAS facilities through the weathering of its plastic components and assessing non-plastic alternatives to these components (e.g. natural biofilters), as well as MNPs removal techniques from the system, is of utmost importance to minimise the presence of these contaminants in RAS, and their impact on global food security.

New recyclable and self-healing elastomer composites using waste from toner cartridges

Product recycling reintroduces what is discarded as waste and minimizes the environmental impact on our society. Among the different types of waste from electrical and electronic equipment, toner recycling often falls short, downcycling plastic components. This study introduces an innovative approach in which waste parts from toner cartridges are valorized to develop (recyclable and) self-healing elastomeric composite materials. The synergy between carboxylated nitrile rubber (XNBR) as the elastomeric phase and high-impact poly (styrene) (HIPS) as the thermoplastic phase derived from toner cartridge waste was explored and optimized. This combination resulted in the creation of a thermoplastic elastomer exhibiting robust mechanical properties and self-healing capabilities with a tensile strength of 6.6 ± 0.2 MPa and a temperature-driven mechanical recovery of 100%. Furthermore, the capacity of toner powder, an integral component of waste, to act as a reinforcing filler was confirmed, with a 50% increase in mechanical strength compared with the unfilled composite. Moreover, an increase in toner content (up to 20 phr) resulted in an optimal balance between tensile strength and self-healing capacity, surpassing the traditional antagonism between these properties. As a result, this research opens a new pathway in the field of self-healing composites and suggests a practical and environmentally friendly approach for managing electronic waste, effectively supporting the principles of Circular Economy.

Development of an Image-based Method for Tablet Microstructure Description and Its Correlation with API Release Rate

The performance of a pharmaceutical formulation, such as the drug (API) release rate, is significantly influenced by the properties of the materials used, the composition of the final product and the tablet compression process parameters. However, in some cases, the knowledge of these input parameters does not necessarily provide a reliable description or prediction of tablet performance. Therefore, the knowledge of tablet microstructure is desirable to understand such formulations. Commonly used analytical techniques, such as X-ray tomography and intrusion mercury porosimetry, are not widely used in pharmaceutical companies due to their price and/or toxicity, and therefore, efforts are made to develop a tool for fast and easy microstructure description. In this work, we have developed an image-based method for microstructure description and applied it to a model system consisting of ibuprofen and CaHPO4∙2H2O (API and excipient with different deformability). The obtained parameter, the quadratic mean of the equivalent diameter of the non-deformable, brittle excipient CaHPO4∙2H2O, was correlated with tablet composition, compression pressure and API release rate. The obtained results demonstrate the possibility of describing the tablet dissolution performance in the presented model system based on the microstructural parameter, providing a possible model system for compressed solid dosage forms in which a plastic component is present and specific API release is required.Graphical