Polypropylene Plates Research Articles

Effect of Functionalization of Texturized Polypropylene Surface by Silanization and HBII-RGD Attachment on Response of Primary Abdominal and Vaginal Fibroblasts.

Soft tissue defects, such as incisional hernia or pelvic organ prolapse, are prevalent pathologies characterized by a tissue microenvironment rich in fragile and dysfunctional fibroblasts. Precision medicine could improve their surgical repair, currently based on polymeric materials. Nonetheless, biomaterial-triggered interventions need first a better understanding of the cell-material interfaces that truly consider the patients' biology. Few tools are available to study the interactions between polymers and dysfunctional soft tissue cells in vitro. Here, we propose polypropylene (PP) as a matrix to create microscale surfaces w/wo functionalization with an HBII-RGD molecule, a fibronectin fragment modified to include an RGD sequence for promoting cell attachment and differentiation. Metal mold surfaces were roughened by shot blasting with aluminum oxide, and polypropylene plates were obtained by injection molding. HBII-RGD was covalently attached by silanization. As a proof of concept, primary abdominal and vaginal wall fasciae fibroblasts from control patients were grown on the new surfaces. Tissue-specific significant differences in cell morphology, early adhesion and cytoskeletal structure were observed. Roughness and biofunctionalization parameters exerted unique and combinatorial effects that need further investigation. We conclude that the proposed model is effective and provides a new framework to inform the design of smart materials for the treatment of clinically compromised tissues.

Conjugate heat transfer from a discrete-source heated plate by offset jet impingement

Convection/conduction simulations have been performed to determine flow and heat transfer phenomena in steady-state, for a plate carrying few embedded discrete heaters, exposed to by a turbulent offset cooling jet. This configuration is relevant, for example, in thermal design of vehicle body segments in aerodynamics conditions: when realized in certain alloys, their configuration will be determined based their discrete structural state prompted by supplied electrical heating. In order to approach an appropriate thermal design of the plate and obtain their precise state, the space of geometric and operating variables needs to be explored by a thorough parametric study based on the governing momentum and energy equations.In this paper, the interaction between the impinging boundary layer and the conductive effects produced by such discrete heaters is explored, giving rise to a conjugate heat transfer situation. With a flexible notation for discretized heating and temperature-dependent conduction, dimensionless heat transfer is discussed spanning the entire range of design parameters. Results report considerable variation in heat transfer: as an example, air jet over polypropylene plates brings about peak Nusselt numbers between 2000 and 4000 for an inclined configuration at Re≈1×106 based on nozzle width, with related strong temperature gradients that must be addressed during design, depending on discrete heaters' configuration and properties; whereas for alumina plates the peak Nusselt numbers fall down between 600 and 750, featuring much smoother temperature variations and consequent more stable structural states.

Plastisphere composition in a subtropical estuary: Influence of season, incubation time and polymer type on plastic biofouling

Plastics are abundant artificial substrates in aquatic systems that host a wide variety of organisms (the plastisphere), including potential pathogens and invasive species. Plastisphere communities have many complex, but not well-understood ecological interactions. It is pivotal to investigate how these communities are influenced by the natural fluctuations in aquatic ecosystems, especially in transitional environments such as estuaries. Further study is needed in subtropical regions in the Southern Hemisphere, where plastic pollution is ever increasing. Here we applied DNA-metabarcoding (16S, 18S and ITS-2) as well Scanning Electron Microscopy (SEM) to assess the diversity of the plastisphere in the Patos Lagoon estuary (PLE), South Brazil. Through a one-year in situ colonization experiment, polyethylene (PE) and polypropylene (PP) plates were placed in shallow waters, and sampled after 30 and 90 days within each season. Over 50 taxa including bacteria, fungi and other eukaryotes were found through DNA analysis. Overall, the polymer type did not influence the plastisphere community composition. However, seasonality significantly affected community composition for bacteria, fungi and general eukaryotes. Among the microbiota, we found Acinetobacter sp., Bacillus sp., and Wallemia mellicola that are putative pathogens of aquatic organisms, such as algae, shrimp and fish, including commercial species. In addition, we identified organisms within genera that can potentially degrade hydrocarbons (e.g. Pseudomonas and Cladosporium spp). This study is the first to assess the full diversity and variation of the plastisphere on different polymers within a subtropical Southern Hemisphere estuary, significantly expanding knowledge on plastic pollution and the plastisphere in estuarine regions.

Effect of Adding Al2O3 on the Macrostructure of Friction Stir Welding Polypropylene Sheet

In this study, an experimental investigation has been carried out to determine the effect of alumina (Al2O3) addition in joining polypropylene. Polypropylene is a thermoplastic material used most as a non-metallic material. One of the joining methods that can be applied in Polypropylene is Friction Stir Welding (FSW). The use of Al2O3 as a filler is to modify the polypropylene matrix's properties to improve the joint's quality. The Al2O3 powder with 99 9% purity was inserted along the polypropylene plates in the groove. This research analyzed the role of adding Al2O3 and tool rotation speed concerning the joints' quality. The experiment was performed under different values of tool speed rotation (204 rpm, 356 rpm, 620 rpm, and 1140 rpm) and the presence or absence of the addition of alumina powder. Then, the joint's quality is visually observed by optical macroscopy at the top and cross-section view. From macroscopic observations, adding alumina could make the visual of the joint look better and result in minimum defects than the joint without alumina addition. Instead, the increasing tool speed rotation helped the distribution of alumina during the welding process.

Improvement of mechanical property of joints for polypropylene through ultrasonic implant welding with non-direct contact method

In this paper, an innovative ultrasonic implant welding technology was proposed for the welding of polypropylene (PP) plates. Welding heat required for the interface was provided by rubbing between the metal implant and the horns to avoid damage of the base material. Ultrasonic implant welding of PP plates was conducted under different welding time (tw) in this research, while copper (Cu) mesh was selected as heat transfer implant. The micro morphology and mechanical property of joint were investigated by SEM and tensile test, which shown a strong correlation with tw. The mechanical property of joints increased from 2.8 to 7.6 MPa as tw increased from 3 to 10 s and the maximum joint strength reaches about 80% of the base materials. The evolution of heat distribution with tw was simulated using COMSOL.

An investigation of the effect of structural parameters on the impact properties of sandwich-structured shock absorbers

The purpose of this study is to develop an impact absorber with a core made of sustainable textile waste as an alternative to the conventional honeycomb structure. In this case, the core structure is made of cotton fiber webs recycled from denim waste, and the outer shell is made of polypropylene plates reinforced with carbon, jute, and E-glass woven fabrics. Production of the sandwich structure is carried out using the hot press method. In addition to the fabric types and layer sequences utilized in the outer shell, the geometry of the core structure is altered, and their effect on the drop-weight impact resistance is examined. The prominent results emphasize that the use of high-performance fabrics in the outer shell facing the outer surface increases the impact resistance, and the sizes of the holes to be obtained in the core structure should be optimized in order to be effective in energy absorption. The results reveal that these developed sandwich structures can constitute a promising alternative for the automotive industry.

Computer simulation analyses to improve radio frequency heating uniformity for watermelon seeds by inserting horizontal aluminum and polypropylene (PP) plates in a rectangular PP container

Uneven temperature distribution is a major barrier for applying radio frequency (RF) heating to replace traditional thermal treatments in foods or agricultural products processing, such as pasteurization of watermelon seeds. In this study, simulation models of watermelon seeds heated by RF energy were established using the commercial COMSOL software with or without inserting polypropylene (PP) or aluminum (AL) plate into a rectangular PP container and validated based on experimental results. The effect of inserting PP or AL plate at different horizontal positions on RF heating behavior of watermelon seeds was also analyzed by the validated simulation model. The results showed that inserting PP or AL plate caused different electric field distribution in the second layer of seeds. Meanwhile, when the insertion height increased from 5 to 35 mm, the volumetric RF heating uniformity index (0.033–0.118) for the second layer in seeds with inserting the AL plate was lower than that (0.127–0.165) of samples with inserting a PP plate. The optimal heating uniformity index could be obtained by inserting multiple AL plates with intervals of 10 mm among watermelon seeds. These findings can further be expanded to optimize the heating uniformity for developing an effective RF pasteurization and disinfestation protocol in foods or agricultural products without reducing their quality.

Ultra-rapid resistance welding of polypropylene within 1 s by monofilament implant assistance

In this paper, an innovative ultra-rapid resistance welding process was proposed for the bonding of polypropylene (PP) plates to alleviate the dilemma of edge effect. The ultra-rapid resistance welding of PP plates was conducted under different heating time (th) and diameter (ds) of stainless-steel (SS) wire in this research, the SS wire of ds = 0.6 mm and th = 1 s was separately selected as the most suitable heat transfer implant and welding time. The edge effect was proved by the interface morphology at different positions of the joint and the thermal simulation results of COMSOL.

Effect of ambient air relative humidity on the triboelectric properties of Polypropylene and Polyvinyl Chloride slabs

The humidity of ambient air has always been known to be a major factor in the triboelectric charging of polymers. A study on the influence of this factor was conducted in a climatic test chamber on square-cut Polypropylene (PP) and Polyvinyl Chloride (PVC) plates of dimensions (110 mm × 110 mm x 4.5 mm) rubbed with Aluminum (Al) samples of dimensions (100 mm × 15 mm x 5 mm). The samples were left at least 12 h in the climatic test chamber at fixed temperature (25 °C) and three different values of air relative humidity (20%, 40% and 80%), then rubbed together in a triboelectric charging test bench. The tribocharged PP and PVC samples were then placed under an electrostatic probe to measure the electric potential generated on the surface of the sample. The results of the experiments show that the sign of the tribocharge reverses when the two polymers are exposed to low or high ambient humidity.

Biomimetic approaches towards lightweight composite structures for car interior parts

Due to good density specific mechanical properties and low carbon footprint, natural fibre-reinforced plastic composites made from fleeces and felts are frequently used as automotive interior parts. The industry targets further mass reduction. Following a biomimetic technology-pull approach, natural fibre-reinforced polypropylene plates with improved lightweight potential were produced using compression moulding. Best results were obtained for a sandwich structure with thin, unidirectional flax fibre layers surrounding a needle felt based core. It was inspired by the carapace structure of the red-eared slider Trachemys scripta elegans. The lay-up performed well, not only with a high density specific flexural stiffness of 2.33GPa1/3 cm3/g, strength of 9.46 MPa1/2 cm3/g, and energy dissipation but also through less abrupt failure due to an asymmetric orientation of unidirectional fibres in the two face sheets. Combined with a mass-reduced needle felt as a core, this concept displays a promising and unconventional approach for further mass reduced, sustainable interior panels used as non-visible and visible design elements in the vehicle.

New Insights into the Hourly Manure Coverage Proportion on the Manure Belt in a Typical Layer House for Accurate Ammonia Emission Modeling.

Simple SummaryHourly manure coverage proportion and area on the manure belt are key parameters for estimating ammonia emissions in poultry houses in order to provide environmental control suggestions and achieve the goals of precision poultry farming. In this study, experimental measurements were performed, and binary images were applied to provide new insights into the projected hourly manure coverage area on the manure belt at different layer hen ages. It was demonstrated that manure coverage proportion and area measured at different laying hen ages showed similar trends and values with four distinct stages within 48 h. In addition, statistical analyses found no significant correlation between the hourly increment of manure weight and the hourly increment of manure coverage proportion. The results from the present study are expected to serve as a fundamental input parameter for ammonia emission modeling to more accurately simulate the hourly indoor environment and provide effective mitigation strategies.The main advantage of having livestock, for example, the laying hens, in a controlled environment is that the optimum growth conditions can be achieved with accuracy. The indoor air temperature, humidity, gases concentration, etc., would significantly affect the animal performance, thus should be maintained within an acceptable range. In order to achieve the goals of precision poultry farming, various models have been developed by researchers all over the world to estimate the hourly indoor environmental parameters so as to provide decision suggestions. However, a key parameter of hourly manure area in the poultry house was missing in the literature to predict the ammonia emission using the recently developed mechanistic model. Therefore, in order to fill the gap of the understanding of hourly manure coverage proportion and area on the manure belt, experimental measurements were performed in the present study using laying hens from 10 weeks age to 30 weeks age. For each test, six polypropylene (pp) plates were applied to collect the manure dropped by the birds every hour, and photographs of the plates were taken at the same time using a pre-fixed camera. Binary images were then produced based on the color pictures to determine the object coverage proportion. It was demonstrated that for laying hens of stocking density around 14 birds/m2, the manure coverage proportion at the 24th hour after the most recent manure removal was about 60%, while the value was approximately 82% at the 48th hour. Meanwhile, for laying hens at different ages, the hourly increment of manure coverage proportion showed a similar pattern with four distinct stages within 48 h. The statistical analyses demonstrated no significant correlation between the hourly increment of manure weight and the hourly increment of manure coverage proportion. Finally, prediction models for estimating the hourly manure coverage proportion on the manure belt in typical laying hen houses were provided.

Suitability of plate versus cylinder surface for the development of low flow falling film liquid desiccant dehumidifiers

Liquid desiccant systems (LDS) are promising as they can be driven by renewable energy. Presently, plastic falling film towers are gaining more attention than metallic columns in LDS due to their excellent anti-corrosive characteristics. However, plastics suffer from penurious performance due to their hydrophobic nature. Apart from solid surface wettability, its geometry also plays a vital role in the formation of the continuous thin film over it. In the current experimental work, the dehumidification performance of adiabatic vertical polypropylene (PP) solid circular cylinders is investigated as an alternative to vertical PP plates. Modified circular cylinder surface is prepared following surface modification to overcome hydrophobic nature of the plastic surface. The performance of the circular cylinder surface is compared with the plate surface. It was found that the Plain PP circular cylinder offered 21–200% improvement in dehumidification rate as compared to the Plain PP plate with an average improvement of 55.9%. Similarly, the Modified PP circular cylinder enhanced the dehumidification rate of the Plain PP circular cylinder by 18.2–61% with an average improvement of 31.3%. A new generalized correlation is proposed to predict the effectiveness of adiabatic and non-adiabatic falling film towers by incorporating shear force, enthalpy difference, and moisture transfer potential between liquid desiccant and air along with wetness behavior parameters. The mean effective error of the current correlation is 11.7% for eight datasets. The findings of this study could be useful for designing small capacity low flow falling film tower-based solar hybrid liquid desiccant systems for residential and commercial applications.

Mosquito-Textile Physics: A Mathematical Roadmap to Insecticide-Free, Bite-Proof Clothing for Everyday Life

Simple SummaryMosquitoes can bite across clothing and transmit disease. This is prevented with pesticides applied to clothing. We developed non-insecticidal cloth and garments that provided 100% protection, were comfortable and look-like and feel-like regular clothing.Garments treated with chemical insecticides are commonly used to prevent mosquito bites. Resistance to insecticides, however, is threatening the efficacy of this technology, and people are increasingly concerned about the potential health impacts of wearing insecticide-treated clothing. Here, we report a mathematical model for fabric barriers that resist bites from Aedes aegypti mosquitoes based on textile physical structure and no insecticides. The model was derived from mosquito morphometrics and analysis of mosquito biting behavior. Woven filter fabrics, precision polypropylene plates, and knitted fabrics were used for model validation. Then, based on the model predictions, prototype knitted textiles and garments were developed that prevented mosquito biting, and comfort testing showed the garments to possess superior thermophysiological properties. Our fabrics provided a three-times greater bite resistance than the insecticide-treated cloth. Our predictive model can be used to develop additional textiles in the future for garments that are highly bite resistant to mosquitoes.

Plasma pre-treatment of polypropylene surface for industrial purposes

ABSTRACT The paper describes an experimental investigation of the possibility of industrial modification of surface wettability and adhesion of polymers by the action of a plasma of a gliding discharge generated in air at atmospheric pressure in a simulated production process. The test material was polypropylene plates (PP). The modification was performed by a device with a multi-electrode (four pairs) system, which is not common. The quality of pre-processing and usability was evaluated primarily in terms of the industrial requirements, which means a change in wettability and adhesion expressed by the contact angle/surface free energy value in dependence to sample exposure time expressed by the conveyor belt speed. The surface free energy assessment of a treated polymeric surface by contact angle measurement was carried out by analyzing static sessile drops and evaluated by Owens–Wendt–Rabel–Kaelble (OWRK) model. The results determined a set of operating parameters at which the modification process meets the industrial requirements. By evaluating the change in surface free energy in relation to the storage time, the degree of hydrophobic recovery of the treated samples, i.e. the time stability of the plasma-treated surface, was also determined. It has been found that plasma-treated PP surface fully meets industrial demands and can be stored for at least 50 days.

MULTISENSORY COLORIMETRIC ANALYSIS OF DRUGS DYDROGESTERONE, TROXERUTIN AND ADEMETIONINE USING BARCODES

The aim of this study is to develop a universal, rapid and affordable method for the identification of dydrogesterone, troxerutin, and ademetionine in drugs by multisensor digital colorimetry using a unique two-dimensional code. The developed approach can be applied to rapid detection of counterfeit drugs at the preliminary stage of the analysis (before using more expensive specialized equipment). Materials and methods. To implement the proposed approach, the substances of dydrogesterone (“Abbott Biologicals B.V.”, Netherlands), troxerutin (JSC “Interfarma”, Prague, Czech Republic) and ademetionine (LLC “Farmamed”, Moscow, Russia) , troxerutin capsules 300 mg (LLC “Pranafarm”, Samara, Russia), lyophilisate for an intravenous solution and the intramuscular administration “Heptral” ® (ademetionine) 400 mg (“Abbott Laboratories”, GMBH, Germany), tablets “Duphaston” ® (dydrogesterone) 10 mg (“Abbott Healthcare Products B.V.”, Netherlands), were used. A multisensor colorimetry method has been implemented using the following set of 8 sensors (C 1 -C 8 ): an intact solution – a 96% (v/v) aqueous ethanol solution – C 1 ; 1 mM alcoholic solution of anthraquinone green (CAS#4403-90-1) – C 2 ; a 0.2% aqueous solution of 3-methylbenzothiazolinone hydrazone (CAS#1128-67-2) – C 3 ; a 0.2% methyl orange aqueous solution (CAS#547-58-0) – C 4 ; a 1 mM alcoholic solution of sulforhodamine B (CAS#3520-42-1) – C 5 ; a 1 mM alcoholic solution of 1-hydroxypyrene (CAS#5315-79-7) – C 6 ; 1 mM alcoholic solution of allura red AC (CAS#25956-17-6) – C 7 ; a 1 mM aqueous solution of iron (III) chloride – C 8 . Transparent flat-bottomed polypropylene plates with 96 cells, with a cell volume of 350 µl (Thermo Fischer Scientific, USA, cat. No. 430341) were used as a base for the chip. For obtaining raster images, an Epson Perfection 1670 office flatbed scanner (CCD-matrix) with a removable cover was used. The obtained digital images of the cells were processed using the ImageJ software (Wayne Rasband, National Institutes of Health, USA; http://imagej.nih.gov/ij) with a 24-bit RGB color model (8 bits per channel). Results. The adequacy of the developed approach was confirmed by the analysis of the above-listed drugs. It has been shown that the results obtained have no statistically significant differences from the values determined by the spectrophotometric method. Conclusion. The possibility of using multisensor digital colorimetry for pharmaceutical analysis has been shown. The developed methods for the identification of the active substances can serve as a good supplement to the more expensive traditional methods.

Study of the Influence of the Different Parameters of the Atmospheric DBD Treatment on the Surface Roughness and the Electric Potential Distribution Generated After the Tribocharging of Polypropylene

Square plates of polypropylene (PP), dimensions 100 mm × 100 mm × 4.5 mm, were treated by atmospheric dielectric barrier discharge (DBD) generated between two disk-type electrodes (Ø 75 mm), energized from an ac amplifier 30 kV, 20 mA. The study aimed at evaluating the factors that affect the roughness and the triboelectric behavior of the plasma-treated samples. The alteration of surface aspect after each treatment was clearly visible with the naked eye and the changes were confirmed by measurements carried out with a portable roughness meter (Surftest SJ-210) and a digital microscope (Keyence VHX-7000). The roughness of the PP samples increased from an initial arithmetic mean Ra = 0.06 μm (±0.01 μm) and standard deviation Rq = 0.08 μm (±0.01 μm) to Ra = 0.22 μm (±0.03 μm) and Rq = 0.25 μm (±0.03 μm), respectively. These increases were highly dependent on the air gap distance (10.5-13.5 mm), the treatment time (5-20 min), and the configuration of the DBD cell, i.e., the number (one or two) and the thickness (4-5 mm) of the glass dielectric barriers. Untreated and DBD-treated samples were tribocharged in a linear tribometer, to evaluate the effect of the cold plasma treatment on the electric potential generated on the polymer surface by the triboelectric effect. The electric potential measured by a noncontact electrostatic voltmeter (Trek, 341B) was higher and better distributed over the surface of the plasma-treated samples.

Hot gas implant welding of polypropylene via a three-dimensional porous copper implant

There is an increasing need for joining technologies of thermoplastics, in which hot gas welding is one of the most promising methods. In this paper, an innovative hot gas implant welding technology was used for the bonding of polypropylene (PP). The hot gas implant welding of PP plates was conducted under different heating time (th) in this research, while porous copper was selected as heat transfer implant. The evolution of temperature with th in the welding joint was recorded using thermocouples while the heat distribution was simulated using COMSOL. The test results of the temperature evolution law of the welding interface perfectly matched the simulation results, and directly affected the distribution of welding joint defects. The more th produced by the higher heat input promoted the resin fusion at the interface, which was propitious to reduce the generation of defects. Moreover, the mechanical strength of the hot gas implant welding joint was investigated by tensile lap shear strength (LSS) test. When th = 30 s, the welding joint can reach a maximum mechanical strength of 8.55 MPa, which mean the PP can be joined effectively when the porous copper was selected as a heat transfer implant. The failure interface morphology of different th was characterized by scanning electron microscopy (SEM), and the characteristic area of the failure interface shown a strong correlation with th.

The morphology and mechanical property of hot gas implant welding joint of polypropylene

In this paper, an innovative hot gas implant welding technology was used for the joining of polypropylene (PP). The hot gas implant welding of PP plates was conducted under different heating time (th), while copper (Cu) mesh was selected as heat transfer implant. The evolution of heat distribution with th in the welding joint was simulated using COMSOL. The mechanical property of the hot gas implant welding joint was investigated by tensile test. The micro morphology of joint was characterized by scanning electron microscopy (SEM), and the characteristic area shown a strong correlation with th.

Effect of Neutralizer on Transparency of Nucleating Agent-Containing Polypropylene

The effects of neutralizer species on the transparency of injection-molded plates were studied using isotactic polypropylene (PP) containing a crystal nucleating agent—i.e., 1,3:2,4-bis-o-(4-methylbenzylidene)-d-sorbitol (MDBS). A plate containing lithium stearate (StLi) was more transparent than one containing calcium stearate (StCa) when the MDBS content was 0.1 wt. %. The addition of StLi accelerated the formation of MDBS fibers and the crystallization of PP. However, when the MDBS content was 1.0 wt. %, StCa improved the transparency more effectively than StLi. These results indicate that the combination of an appropriate amount of MDBS and the correct neutralizer species is critical for enhancing the transparency of injection-molded PP plates.

Investigating ion-release from nanocomposites in food simulant solutions: Case studies contrasting kaolin, CaCO3 and Cu-phthalocyanine

• A bulk-filled polypropylene with a metal-organic nanopigment and a doubly coated paperboard with a nanoscaled kaolin filler were investigated. • Up to 60 % release of Ca (from CaCO 3 base coating) vs. 0.4% of Al and max. 0.7% of Si (both from kaolin top coating) were released from paperboard. • The release was mainly ionic but the presence of a few nanoparticles (NPs) consistent with Kaolin but not with CaCO 3 was confirmed as well. • No Cu release was detected from the polypropylene plates and consequently no released pigment nanoparticles were found. • High ionic release rates occur for soluble NPs when the food simulant is able to penetrate into the nanocomposite and reach the NPs. Nanocomposites, due to their enhanced properties, are interesting for various industrial applications. Investigating a possible release of the incorporated nanoparticles (NPs) is a central part in their safety assessment. Here we analysed two different nanocomposites, polypropylene (PP) containing a nanoscaled Cu-phthalocyanine pigment and a paperboard containing nanoscaled kaolin filler. The release of kaolin and CaCO 3 from the paperboard was assessed at room temperature in five different food simulant solutions, i.e. water, 3% (w/v) acetic acid solution (HAc) and aqueous ethanol (EtOH) solutions at 10 %, 50 % and 95 % (v/v). Cu-phthalocyanine release from PP was assessed in 3% (w/v) HAc and 10 % (v/v) EtOH at 40 °C. Quantification was based on measuring Al and Si (kaolin) and Cu (Cu-phthalocyanine) using inductive coupled plasma mass spectrometry (ICP-MS). For the coated paper, release could be detected in different solutions with highest release of Al (3.6 μg/cm 2 , corresponding to 0.4 % of kaolin content) and Ca (1,200 μg/cm², corresponding to 60 ± 18 % of CaCO 3 content) in 3% HAc. The presence of NPs, occasionally consistent with Kaolin, but not with CaCO 3 was confirmed using single particle ICP-MS and TEM. In contrast, no Cu release was detected from the PP plates and consistently no NPs were found. In conclusion, high ionic release rates occur for soluble NPs when the food simulant solution is able to reach the NPs, i.e. can penetrate into the nanocomposite. This study is an important contribution in understanding possible human health risks of nanocomposites being increasingly used in different applications.