Plastic Composites Research Articles

Shelf-life prediction of chicken nuggets based on the thickness level of composite plastic packaging using accelerated shelf-life testing (ASLT) method by the Arrhenius equation approach

The packaging of ground chicken meat, known as chicken nuggets, generally experiences a very rapid rate of deterioration caused by microorganisms. To determine the shelf life of chicken nuggets, shelf life measurements are made by accelerating product degradation through environmental conditions such as temperature, humidity, gas atmosphere, and light. In this study, the thickness level of composite plastic packaging was tested using the accelerated shelf-life testing (ASLT) method with the Arrhenius equation approach. The study looked at the critical period of chicken nuggets packed in 15μm nylon and LLDPE composite plastic packaging with a thickness of 40μm and 50μm stored in an incubator at 45°C for two days, then sensory evaluation once a day and calculated the shelf life, where chicken nuggets were packed in 15μm nylon and LLDPE composite plastic packaging with a thickness of 40μm and 50μm and stored in an incubator with temperature variations of -15, 5 and 25 °C for 25 days, every five days analyzed for moisture content and TPC. The best shelf life of chicken nuggets is found in 50μm thickness composite plastic packaging at a temperature of -15 °C, lasting 136 days.

Insights into the enhanced mechanism of electron beam pretreatment on application performance for poly (butylene adipate-co-terephthalate)/acetylated cellulose composite plastics

In this work, we developed a strategy to construct poly (butylene adipate-co-terephthalate) (PBAT) composite plastics with excellent mechanical properties, superior thermal stability and enhanced biodegradability by combining acetylated celluloses (ECs) mediated by electron beam irradiation (EBI), which works as a toughening agent. With findings, the EBI pretreatment assisted with acetylation was applied to develop ECs materials with a higher degree of acetylation than acetylation alone. The pretreated ECs with increased hydrophobicity tended to decrease the chance of self-aggregation and enhanced the interfacial compatibility and adhesion with PBAT in PBAT/ECs composite plastics. Thus, PBAT/ECs composite plastics exhibited a smoother and more uniform surface structure during preparation and offered higher tensile strength, water vapor transmission rate, water absorption rate, thermal stability and degradation rate, and lower elongation at a break during application. On top of that, the PBAT/ECs composite plastics were characterized by a series of methods containing Fourier transform infrared spectroscopy and X-ray diffraction, indicating that these properties are mainly caused by the acetylation of hydroxyl groups from cellulose and carboxyl groups of PBAT. The work is expected to expand the application scope of PBAT and cellulose and provide an attainable solution for a biodegradable substitute for traditional plastics.

The amygdala NT3-TrkC pathway underlies inter-individual differences in fear extinction and related synaptic plasticity

Fear-related pathologies are among the most prevalent psychiatric conditions, having inappropriate learned fear and resistance to extinction as cardinal features. Exposure therapy represents a promising therapeutic approach, the efficiency of which depends on inter-individual variation in fear extinction learning, which neurobiological basis is unknown. We characterized a model of extinction learning, whereby fear-conditioned mice were categorized as extinction (EXT)-success or EXT-failure, according to their inherent ability to extinguish fear. In the lateral amygdala, GluN2A-containing NMDAR are required for LTP and stabilization of fear memories, while GluN2B-containing NMDAR are required for LTD and fear extinction. EXT-success mice showed attenuated LTP, strong LTD and higher levels of synaptic GluN2B, while EXT-failure mice showed strong LTP, no LTD and higher levels of synaptic GluN2A. Neurotrophin 3 (NT3) infusion in the lateral amygdala was sufficient to rescue extinction deficits in EXT-failure mice. Mechanistically, activation of tropomyosin receptor kinase C (TrkC) with NT3 in EXT-failure slices attenuated lateral amygdala LTP, in a GluN2B-dependent manner. Conversely, blocking endogenous NT3-TrkC signaling with TrkC-Fc chimera in EXT-success slices strengthened lateral amygdala LTP. Our data support a key role for the NT3-TrkC system in inter-individual differences in fear extinction in rodents, through modulation of amygdalar NMDAR composition and synaptic plasticity.

Use of melt blending to synthesize wood plastic composites containing modified steel slag: a study

ABSTRACT .The novel modified steel slag/wood-plastic composites were innovatively prepared by melt blending with melt pressure 4.8 MPa ascribed to simpler operation. The addition of modified steel slag could be grafted on the molecular chain of polyethylene and wood powder using melt blending, producing chemical correlations. Their higher flexural strengths in the range of 24.78~32.35 MPa in accordance with GB/T 24137-2009 were used as indoor and outdoor decorative panels. Especially, the wood-plastic composite with 16 wt.% modified steel slag possessed the most optimal tensile strength and flexural strength achieving 17.36 MPa and 32.35 MPa which increased by 16.1% and 9.1% compared with talc powder/wood-plastic composites, respectively. Moreover, modified steel slag containing aluminum oxide, silicon dioxide, magnesium oxide and phosphorus pentoxide combined with residual substances of polyethylene and wood powder, resulting in a rapidly condensed form as a protective shield during combustion, increasing char yields as well as heat resistance.

Transparent biodegradable composite plastic packaging film from TEMPO-oxidized cellulose nanofibers

In this research, we develop a method to create biodegradable food packaging films. Initially, TEMPO-oxidized cellulose nanofiber (TOCNF) undergoes sonication to produce well-dispersed single-strain nanofibers. These nanofibers are then blended with waterborne polyurethane (WPU) to enhance their extensibility. To further enhance compatibility between these two components, a non-ionic surfactant, Tween 80, is introduced into the TOCNF/WPU mixture to improve the dispersion of the WPU within the blend. The addition of Tween 80 significantly increases the transparency of the resulting film (Transmittance: 89.4 %, Haze: 2.2 %). Furthermore, the incorporation of the surfactant effectively reduces the formation of wrinkles and cracks during the film drying process, preventing adverse impacts on the film's barrier properties. The thin film further undergoes esterification crosslinking with citric acid to remove its hydrophilic groups for better water vapor barrier properties. The resulting bio-based packaging film exhibits remarkable transparency, strong biodegradability, and superior gas-barrier properties (water vapor and oxygen) compared to commonly used food packaging.

Damping materials based on plasticized polybutyl methacrylate, polymethyl methacrylate and polyvinyl acetate

The purpose of the presented work is to investigate by DMA method the influence of the composition of filled and unfilled plasticized compositions based on polyvinyl acetate (PVA), polybutyl methacrylate (PBMA) and polymethyl methacrylate (PMMA) on their damping characteristics. It was found that when plasticizer is introduced into the polymer, the value of the mechanical loss coefficient first increases, reaches its maximum, and begins to decrease with further increase in the plasticizer content. The maximum effect is observed at a plasticizer/polymer volume ratio of 0.2-0.4. Two other dissipative characteristics, the temperature interval of effective damping and the integral coefficient of mechanical losses, are changing similarly. It is established that the additives of chlorinated paraffins in compositions based on PVA and PBMA can significantly improve their vibration absorbing characteristics. Introduction of mica filler into the composition of plasticized compositions based on PVA and PBMA does not lead to the appearаnсe of additional relaxation mechanisms. With increasing of the content of mica, the elastic modulus of compositions increases in the entire temperature range (especially significantly for compositions with a high content of plasticizer), the coefficient of mechanical losses slightly decreases, and the temperature practically does not change at which the maximum damping is observed.

The Impact of Plasticizers on the Nature of the Alkali-Silicate Corrosion in Cement Composites

This research work attempts to reveal the mechanism of alkali corrosion in cement composites in the presence of plasticizers based on polycarboxylates (PCE), naphtha-lene-formaldehydes (SPNF), and lignosulfonates by maintaining a high pH of the liquid phase and additionally containing monovalent alkali earth metals in cement stone, as well as stopping this process by introducing an active mineral additive. ASR is studied by changing the relative strain with time according to ASTM C-1260. Deformation changes were confirmed by SEM and RFA studies of hydration products and ASR in the microstructure. Separate use of PCE plasticizers in the cement composition increases deformation by 50% to the 56th day; the use of SPNF increases deformation by 10% compared with the additive-free composition. The use of PLS reduces the relative deformation by 25%. The introduction of silica fume into cementitious composites containing plasticizers actually stops ASR only for a short time. A reduction in deformation during MC use together with plasticizer based on naphthalene sulfonate and polycarboxylate occurs only when the dosage of MS is increased to 20–30%; at a lower dosage, the effect is negative, which also affects the phase composition of the composites. The introduction of MC increases the value of the relative deformation compared with plasticizer compositions based only on PLS. SEM studies have detected microcracks and dense fine-crystalline silicate gel, which cause deformation changes in cement composite samples. Research has shown that concrete modified with SPNF and PCE at the maximum dosage of MC (30%) has minimal deformation rates and can be used to select optimal concrete compositions. The results of this study could help to minimize risks, prevent unacceptable expansion, and ensure the high quality of concrete and concrete products during their use as part of various nature-modifying additives.

Rapid single-particle chemical imaging of nanoplastics by SRS microscopy.

Plastics are now omnipresent in our daily lives. The existence of microplastics (1 µm to 5 mm in length) and possibly even nanoplastics (<1 μm) has recently raised health concerns. In particular, nanoplastics are believed to be more toxic since their smaller size renders them much more amenable, compared to microplastics, to enter the human body. However, detecting nanoplastics imposes tremendous analytical challenges on both the nano-level sensitivity and the plastic-identifying specificity, leading to a knowledge gap in this mysterious nanoworld surrounding us. To address these challenges, we developed a hyperspectral stimulated Raman scattering (SRS) imaging platform with an automated plastic identification algorithm that allows micro-nano plastic analysis at the single-particle level with high chemical specificity and throughput. We first validated the sensitivity enhancement of the narrow band of SRS to enable high-speed single nanoplastic detection below 100 nm. We then devised a data-driven spectral matching algorithm to address spectral identification challenges imposed by sensitive narrow-band hyperspectral imaging and achieve robust determination of common plastic polymers. With the established technique, we studied the micro-nano plastics from bottled water as a model system. We successfully detected and identified nanoplastics from major plastic types. Micro-nano plastics concentrations were estimated to be about 2.4 ± 1.3 × 105 particles per liter of bottled water, about 90% of which are nanoplastics. This is orders of magnitude more than the microplastic abundance reported previously in bottled water. High-throughput single-particle counting revealed extraordinary particle heterogeneity and nonorthogonality between plastic composition and morphologies; the resulting multidimensional profiling sheds light on the science of nanoplastics.

Atomistic simulation of plasticity in Cu/Nb metallic nanolayered composites with thick interfaces

Interface structure plays a vital role in plasticity of metallic nanolayered composites (MNCs). In this work, we explore the effects of thick three-dimensional (3D) interface structures on deformation behavior of Cu/Nb MNCs by using molecular dynamics simulation. Our analysis reveals that the 3D interface structure is crystalline dominant rather than amorphous and dislocations are distributed on multiple slip planes within the 3D interface region. The effect of layer thickness on the strength of MNCs has been suppressed by the 3D interface structure, which can also inhibit shear band formation.

Mechanical and electrical performance of glass fiber reinforced plastic insulation for cryogenic application in fusion magnet irradiated in fast breeder reactor

In a superconducting (SC) magnet fusion reactor, the insulation material used has to withstand significant fluxes of neutrons and neutron-induced gamma radiation. Epoxy-based glass fiber-reinforced plastic (GFRP) composites are the insulation system for fusion magnets and are highly demanding. This insulation system requires excellent mechanical and electrical performance under mixed neutron and gamma radiation at cryogenic temperatures. The insulation material developed consists of boron-free S-glass fiber impregnated with a two-component modified Diglycidyl ether of Bisphenol-A (DGEBA) epoxy resin. An anhydride-cured DGEBA resin system is not suitable for cryogenic temperatures. Therefore, to overcome this thermal stress issue in cryogenic components of SC magnets, a high-toughness, flexible, aromatic amine-cured epoxy resin system was developed for the insulation system. In order to assess the radiation resistance for mechanical and electrical properties, the composite samples were irradiated in the fast breeder test reactor (FBTR) at IGCAR, Kalpakkam, India. The irradiation experiment was carried out for a neutron fluence of 1.0E+21 n/m2 and a gamma dose of 0.4 MGy at a full reactor power of 32 MWt. The tensile strength, interlaminar shear strength, and breakdown strength measurements were investigated before and after irradiation at room temperature and 77 K. The test results indicate that no significant degradation was observed in the properties of the irradiated samples up to the above-mentioned radiation doses.

Adaptive Machining Method for Helical Milling of Carbon Fiber-Reinforced Plastic/Titanium Alloy Stacks Based on Interface Identification.

CFRP/Ti stacks composed of carbon fiber-reinforced plastic composites (CFRP) and titanium alloys (Ti) are widely used in aerospace fields. However, in the integrated hole-making process of CFRP/Ti stacks, the machining characteristics of various materials are significantly different, and constant machining parameters cannot simultaneously meet the high-quality machining requirements of two materials. In addition, errors exist between the actual thickness of each material layer and the theoretical value, which causes an impediment to the monitoring of the machining interface and the corresponding adjustment of parameters. An adaptive machining method for the helical milling of CFRP/Ti stacks based on interface identification is proposed in this paper. The machining characteristics of the pneumatic spindle and the interface state in the helical milling of CFRP/Ti stacks are analyzed using self-developed portable helical milling equipment, and a new algorithm for the real-time monitoring of the machining interface position and adaptive adjustment of the machining parameters according to the interface identification result is proposed. Helical milling experiments were carried out, the results show that the proposed method can effectively identify the position of the machining interface with good identification accuracy. Moreover, the proposed parameter-adaptive optimized machining method for CFRP/Ti stacks can significantly improve hole diameter accuracy and machining quality.

Improving interfacial bonding strength between epoxy and PE-based wood plastic composites by micro-riveting

In this paper, we proposed a micro-riveting method using the wood fibers in the wood plastic composites (WPC) to effectively enhance the interfacial bonding strength between the epoxy coating and polyethylene (PE) -based WPC. The WPC surface with wood fibers partially embedded in the PE matrix was prepared using a simple solvent swelling and polishing method. Epoxidized Cardol having a long and hydrophobic chain was modified on the surface of the exposed wood fibers to improve the water-resistance and chemical reactivity of the wood fiber surface. Fourier transforms infrared (FT-IR) spectra, X-ray photoelectron spectroscopy (XPS), contact angle, confocal microscopy, and scanning electron microscope (SEM) have been used to characterize the composition and morphology of the surface structures. A pull-off test has been used to evaluate the interface bonding strength, which increased from 1.88 to 5.27 MPa. This constitutes the highest performance among all the non-plasma surface treatment reports (30 % higher than the highest bonding strength reported in the literature and comparable to plasma-based surface treatments). The epoxy-WPC interface showed excellent water resistance after immersing in sodium chloride (NaCl) solution (3.5 wt%) for 60 days. The proposed micro-riveting method is of high significance for WPC and may contribute to the interface adhesion enhancement of other polymer composites.

Oxovanadium(IV) heteromacrocyclic complexes as ionophores for iodide-selective electrodes

Abstract Highly selective poly(vinyl chloride) (PVC) membrane electrodes, based on oxovanadium(IV) complexes of heteromacrocyclic compounds as new iodide-selective ionophores for ion-selective electrodes (ISEs), were fabricated with a composition of PVC (28.1 wt%), plasticizers (69.3 wt%), ionophores (2.6 wt%), and cation excluders (15 mol% relative to the ionophore). The electrode prepared from oxovanadium(IV) tetraphenyl porphyrin with 2-nitrophenyl octyl ether (o-NPOE) as the membrane solvent and tetradodecylammonium chloride (TDDACl) as the cation excluder was found to exhibit the best sensitivity over a wide concentration range from 5.0 × 10–7 to 2.1 × 10–2 M with a Nernstian response of −59.02 mV per decade and the highest ion-selectivity toward I− ions over perchlorate ions (I−/ClO4− = 91).

Comparative performance evaluation between ta-C and TiAlCrN coated tools during milling of additively manufactured CFRP composite

Due to the excellent strength-to-weight ratio and corrosion resistance properties, the application of carbon fibre-reinforced plastic (CFRP) composites is rising among various industries day-by-day. This research addresses the performance evaluation of tetrahedral amorphous hard carbon (ta-C) and TiAlCrN coated carbide tools during milling of additively manufactured CFRP composite under dry environment. Tool rotational (spindle) speed, feed and depth of cut are considered as the variable factors in order to evaluate the machining performance characteristics in milling operation concerning surface roughness (Ra), cutting force (Fc) and cutting temperature (T). Taguchi's L16 orthogonal array design of experiments was adopted to conduct the machining trials under various settings of process variables. The relative influence of the different types of coatings and different operating parameters on machined surface morphology in milling was analysed by scanning electron microscope. From the experimental results, a promising machining performance is noticed for TiAlCrN coated carbide end milling tool accomplished by physical vapour deposition technique in terms of all machining attributes compared to ta-C coated end milling tool due to superior wear resistance, surface hardness and bonding strength of coating material. Among the tools used, TiAlCrN coated carbide tools for CFRP milling application promises excellent machinability performances in terms of reduced cutting force, enhanced machined surface morphology as well as surface finish, and minimum cutting temperature. The mean value ratios for Ra ta-C/RaTiAlCrN, Fc ta-C/FcTiAlCrN and T ta-C/TTiAlCrN are 1.44, 1.24 and 1.21, respectively.

The Effects of Polyolefin Structure and Source on Pyrolysis-Derived Plastic Oil Composition

Seven types of plastics were pyrolyzed in a fluidized bed reactor: post-consumer recycled (PCR) high-density polyethylene (HDPE), PCR polypropylene (PP), virgin resins of varying molecular weights of HDPE, virgin resins...

Investigate on the physical and mechanical properties of wood-polymer composition materials made on the premise of neighborhood wood flours

This study aims to demonstrate the feasibility of obtaining wood-polymer composites, which focus on materials that are difficult to recycle. For this purpose, local poplar and pavloniya wood samples, the density of which corresponds to this process, were impregnated with polyvinyl chloride and CaCO3, which form free radicals. Samples were taken using a hot press. Physico-mechanical parameters of the samples were analyzed. Due to the low permeability of the poplar wood showed only increasing values of stiffness parallel and perpendicular to the grain. Undebarked ponderosa pine chips were treated by hot water extraction to modify the chemical composition. In the treated pine (TP), the mass was reduced by approximately 20%, and the extract was composed mainly of degradation products of hemicelluloses. Wood flour produced from TP and unextracted chips (untreated pine, UP) was blended with high-density polyethylene (HDPE) and polypropylene (PP) and was extruded into wood plastic composites (WPCs).

ANALYSIS OF AIRFLOW RESISTIVITY AND ACOUSTIC ABSORPTION OF FIBRE-REINFORCED PLASTIC COMPOSITES MADE OF POLYLACTIC ACID AND NATURAL FIBRES

This study compares the airflow resistivity and acoustic properties of fibre-reinforced plastic composites (NFRP) with different mixing ratios of polylactic acid (PLA) and the natural fibres flax and cotton for the application in construction as lightweight structures, car door linings or seat pans. The composites are made from the binder fibre PLA, the bast fibre flax and two different kinds of cotton. Nonwovens are consolidated with a thermoforming process to manufacture the NFRP. The addition of cotton improves the absorption by increasing the number of air pockets (pores) and reducing their shape due to the fineness of the cotton. The airflow resistivity of samples with different mixing ratios were analysed and compared. The airflow resistivity is modelled with different calculation models that use distinct material parameters and the transferability is assessed. Further, the absorption coefficient is analysed and compared to the airflow resistivity. The study shows that there is a dependency of the two parameters.

Enhancing mechanical properties of waste expanded polystyrene composites through varied coupling agents and wood powder formulations

This study investigates Wood Plastic Composites (WPCs) by incorporating waste Expanded Polystyrene (EPS) and various wood powder reinforcements. The mechanical properties of WPCs play a pivotal role in sustainable material development. Our research delves into the effects of different treatments on wood powders and their interactions with the polymer matrix.Pine, teak, and silk tree wood powders underwent alkali immersion and coupling agent treatments. The ensuing composites underwent rigorous testing, including flexural strength, hardness, and impact resistance assessments.The findings underline the complex factors governing WPC mechanical properties. Pine-based WPCs, reinforced with pine wood powder and subjected to alkali treatment, exhibited the highest flexural strength at 29.56 MPa, whereas the lowest flexural strength of 14.65 MPa was observed in WPCs reinforced with alkali-treated teak wood powder. The highest impact strength quantified at 2.54 kJ/cm², was found in untreated pine wood powder-based WPC. In contrast, the lowest impact strength was identified in teak wood powder-based WPC treated with alkali.

Analysis of tensile strength of composite fiber reinforced with areca Nut Skin Fiber using BQTN 157 EX Resin

In the development of materials science, especially polymers, natural fibers such as areca nut shell fiber are increasingly attractive to use. The use of synthetic polymer materials made from fiber can replace conventional materials such as metal, wood and leather. They can replace conventional materials with the advantages of lower price, environmental friendliness, and recyclability. Areca nut shell fiber, as an example of a natural fiber, has great potential in the furniture industry, crafts, and as an ingredient in traditional medicine. This fiber is used as a reinforcing material in composites with an Unsaturated Polyester Yukalac resin matrix. Unsaturated Polyester Yukalac resin, with characteristics such as stiffness, flexibility, water resistance, chemical resistance and weather resistance, is used as a matrix in making composites. The aim of this research is to make a plastic composite prototype reinforced with areca palm fiber, varying the volume fraction of areca nut shell fiber by 30%:50%, 50%:60%, 70%:70%, 90%:80% and for the matrix using polyester resin. BQTN 157 EX. The fiber composition is arranged in a mold in the same direction using the hand lay up method. Composite testing is in the form of a tensile test referring to the ASTM 638-03 standard. The results of the largest tensile testing process were with a volume fraction of 50% with an average value of 7.11 MPa, and for tensile testing the lowest was a volume fraction of 70% with an average value of 6.17 MPa, it can be concluded for reinforced plastic composites Areca nut shell fiber has considerable ability to be applied as a structural material. This is a step towards the development of innovative and environmentally friendly composite materials for various industrial applications.

Physical Behaviour of Wood Plastice Composite Made of Recycled High-Density Polyethylene (HDPE)

This paper investigated the physical characteristics of wood–plastic composites, which were made using recycled high-density polyethylene (HDPE) and using wood flour from Pometia sp (Matoa), Intsia sp (Merbau) and Alstonia sp (Pulai) as filler. The sawdust was taken from local furniture industry and the HDPE was collected from recycled plastic bottles of mineral water. Composite panels were made from recycled HDPE through hot-press moulding produced excellent stability based on JIS and SNI Standard, especially for moisture content and swelling characteristics. The water absorption and targeted density were also measured. In this study we found that the water absorption and the density of the composite exceeded our expectation. The composites showed high variation average for water absorption. For the swelling behavior, the value is varied from 5.74% to 25.57% after 2 hours soaking and varied between 7.56% to 28.53% after 24 hours soaking. This study has shown the composites had a high possibility to be used for interior and non-structural purposes.