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The global challenge of oil spill treatment has been addressed using nanocomposite-based natural fibers. These materials offer great potential in oil spill cleanup and are considered due to their environmental friendliness, high efficiency, and low cost. Thus, the current study reports a novel composite fabricated from date palm fiber (DPF) and recycled polyethylene terephthalate (rPET) with a proper combination of a mixture of carbon nanotubes (CNTs) and graphene nanosheets (GNSs) for oil removal. The established nanocomposite (DPF-rPET/CNT/GNS) was fabricated via physical mixing of various quantities (0.9, 0.8, and 0.7 g) of PET, along with varying loads of DPF at different proportions of CNT:GNS. The prepared nanocomposite (DPF-rPET/CNT/GNS) was fully characterized using scanning electron microscopy–energy dispersive X-ray (SEM-EDX) analysis, transmission electron microscopy (TEM), thermogravimetric analysis (TGA), Fourier-transform infrared spectroscopy (FTIR), and Brunauer–Emmett–Teller (BET) analysis. In static experiments and under the optimal parameters of pH, sorbent doze, shaking time, and quantity of diesel oil), the established sorbent (DPF-rPET/CNT-GNS nanocomposite) displayed excellent adsorption capacity (98 mg/g). This study also expands the utility of the sorbent for the reusability of the oil adsorption, maintaining performance after five cycles. The adsorption data fitted well with the Langmuir isotherm model with a correlation coefficient (R2) of 0.99 and maximum adsorption capacity of 99.7 mg/g, indicating monolayer adsorption. Additionally, the adsorption kinetics followed a pseudo-second-order model, with an R2 near unity and an adsorption capacity of 99.09 mg/g. This study highlights the promising potential of the DPF-rPET/CNT-GNS composite as an effective adsorbent for treating oily water. [ABSTRACT FROM AUTHOR]

Recycling polyethylene terephthalate (PET) bottles post‐consumption is highly desirable but remains challenging because of their poor properties after recycling. Using a chain extender to rejoin the cleaved polymer chains is considered a reasonable solution to this issue. However, the functionality of the chain extenders affects the cross‐linking and properties of the resulting products. Therefore, this study focuses on the effects of functional groups and number of chain extenders on the properties of recycled polyethylene terephthalate (rPET). Three commercial chain extenders—methylene diphenyl diisocyanate (MDI), triphenyl phosphite (TPP), and Joncryl (JC), represented as di‐, tri‐, and multi‐functional chain extenders, respectively—are introduced into rPET by reactive blending. The intrinsic viscosity, rheological properties, thermal properties, and mechanical properties of the chain‐extended rPET are investigated. The results indicate that all the chain extenders increase the molecular weight of rPET. Di‐ and multi‐functional chain extenders (MDI and JC) induce branching and cross‐linking owing to the highly reactive functional groups, whereas a tri‐functional chain extender (TPP) showed the lowest improvement in mechanical properties, owing to chain scission from by‐products occurring during chain extension. Furthermore, increasing the content of all chain extenders significantly increased their intrinsic viscosity, cross‐linking, and mechanical properties. [ABSTRACT FROM AUTHOR]

To solve the decrease in the crystallization, mechanical and thermal properties of recycled polyethylene terephthalate (rPET) during mechanical recycling, the aromatic amide fatty acid salt nucleating agents Na-4-ClBeAmBe, Na-4-ClBeAmGl and Na-4-ClAcAmBe were synthesized and the rPET/nucleating agent blend was prepared by melting blending. The molecular structure, the thermal stability, the microstructure and the crystal structure of the nucleating agent were characterized in detail. The differential scanning calorimetry (DSC) result indicated that the addition of the nucleating agent improved the crystallization temperature and accelerated the crystallization rate of the rPET. The nucleation efficiencies (NE) of the Na-4-ClBeAmBe, Na-4-ClBeAmGl and Na-4-ClAcAmBe were increased by 87.2%, 87.3% and 41.7% compared with rPET which indicated that Na-4-ClBeAmBe and Na-4-ClBeAmGl, with their long-strip microstructures, were more conducive to promoting the nucleation of rPET. The equilibrium melting points (T 0 m) of rPET/Na-4-ClBeAmBe, rPET/Na-4- ClBeAmGl and rPET/Na-4-ClAcAmBe were increased by 11.7 ◦C, 18.6 ◦C and 1.9 ◦C compared with rPET, which illustrated that the lower mismatch rate between rPET and Na-4-ClBeAmGl (0.8% in b-axis) caused Na-4-ClBeAmGl to be the most capable in inducing the epitaxial crystallization and orient growth along the b-axis direction of the rPET. The small angle X-ray diffraction (SAXS) result proved this conclusion. Meanwhile, the addition of Na-4-ClBeAmGl caused the clearest increase in the rPET of its flexural strength and heat-distortion temperature (HDT) at 20.4% and 46.7%. [ABSTRACT FROM AUTHOR]

This study focused on manufacturing efficient automobile sound-absorbing materials through alkaline treatment and dimple processing of recycled polyethylene terephthalate (rPET) nonwoven fabric. The rPET nonwoven fabric was produced with a sound-absorbing material through compression molding. It was improved through the development of porous sound-absorbing materials through alkaline treatment and resonant sound-absorbing materials through dimple processing. As a result of morphological analysis, alkaline treatment showed that pore size and air permeability increased according to temperature and concentration increase conditions. On the other hand, dimple processing caused a decrease in air permeability and a decrease in pores due to yarn fusion, and as the dimple diameter increased, the sound-absorbing coefficient increased in the 5000 Hz band. Finally, it was judged that effective sound absorption performance would be improved through a simple process through alkaline treatment and dimple processing, and thus there would be applicability in various industrial fields.

[Display omitted] • VOCs of PET at various recycling stages are identified by HS-SPME-GC-GC-qTOF-MS. • Chemometric analysis indicates the difference of PET at various recycling stages. • The elimination efficiency of FA obtained by HS-SPME reaches 100 %. • VOCs were primarily removed during the decontamination and melt-extrusion processes. The recycling of polyethylene terephthalate (PET) stands as an effective strategy for mitigating plastic pollution and reducing resource waste. The study aimed to investigate the characterization and elimination efficiency of volatile organic compounds (VOCs) present in rPET at various recycling stages using comprehensive two-dimensional gas chromatography-quadrupole-time-of-flight-mass spectrometry coupled with chemometrics. The results revealed that 52, 135, 95, 44, and 33 VOCs, mostly classified into three chemical groups, were tentatively identified in virgin − PET (v-PET), cold water washed − rPET (C-rPET), decontaminated − rPET (D-rPET), melt-extruded − rPET (M-rPET), and solid-state polycondensation − rPET (S-rPET), respectively. Regarding the VOCs with high and median detection frequencies, fatty acyls showed the highest elimination efficiency (100 % and 92 %), followed by organooxygen compounds (81 % and 99 %), others (97 % and 95 %), and benzene and substituted derivatives (82 % and 95 %) in term of HS-SPME. Following the recycling process, there was a general decrease in the concentration of almost all VOCs, as evidenced by the substantial reduction of o-Xylene, hexanoic acid, octanal, and D-limonene from 18.11, 22.43, 30.74, and 7.41 mg/kg to 0, 0, 3.97, and 0 mg/kg, respectively. However, it was noteworthy that the VOCs identified in the samples were not completely extracted, owing to the limitations of HS-SPME. Furthermore, chemometrics analysis indicated significant discrimination among VOCs from vPET, C-rPET, D-rPET, and M-rPET, while indistinct differences were observed between M-rPET and S-rPET. This study contributes to the enhancement of the recycling process and emphasizes the importance of safeguarding consumer health in terms of elimination of VOCs. [ABSTRACT FROM AUTHOR]

This study focused on manufacturing efficient automobile sound-absorbing materials through alkaline treatment and dimple processing of recycled polyethylene terephthalate (rPET) nonwoven fabric. The rPET nonwoven fabric was produced with a sound-absorbing material through compression molding. It was improved through the development of porous sound-absorbing materials through alkaline treatment and resonant sound-absorbing materials through dimple processing. As a result of morphological analysis, alkaline treatment showed that pore size and air permeability increased according to temperature and concentration increase conditions. On the other hand, dimple processing caused a decrease in air permeability and a decrease in pores due to yarn fusion, and as the dimple diameter increased, the sound-absorbing coefficient increased in the 5000 Hz band. Finally, it was judged that effective sound absorption performance would be improved through a simple process through alkaline treatment and dimple processing, and thus there would be applicability in various industrial fields. [ABSTRACT FROM AUTHOR]

In this study, physical characterization and monitoring of volatile organic compounds (VOCs) were investigated on recycled polyethylene terephthalate (rPET) from a mechanical recycling process and rPET bottles made with different rPET contents, with the aim of tracing the source of rPET and assessing its safety when use as a food contact material. It was found that rPET had a similar thermal stability to that of virgin PET (vPET). rPET bottles did not show any significant changes in groups or structure and exhibit similar crystallization and melting behaviors to vPET. However, there were minor mechanical scratches in the surface micromorphology of rPET bottles, and the color of rPET bottles became darker, greener and yellower as the content of recycled material increased. The solid-state polycondensation process was found to play an important role in the removal of VOCs, as detected by headspace gas chromatography-mass spectrometry (HS-GC-MS), resulting in a very small amount of residual VOCs in rPET. Four VOCs (acetaldehyde, glycol and nonanal at levels less than 1.00 mg/kg; 2-methyl-1,3 dioxolane at levels of 1.72-5.76 mg/kg) were detected in the rPET bottles. This study shows that rPET bottles are qualified for reuse in food contact in terms of thermal properties, structure, morphology and VOC residues, although there is variability in color.

Post-harvest activities, which include sorting, loading, unloading, and transporting, are potential factors that cause mechanical damage and bruises to fresh produce. This would directly impact fruit shelf-life and, therefore, cause economic losses. This study developed a finite element (FE) model for pear fruit where a steel impactor drop-based test was utilized. The FE model was validated by evaluating it as the experimental model in order to identify bruises of the pear fruit. Therefore, to minimize bruises on the pear fruit, a recycled polyethylene terephthalate (PET) spring-based design was proposed in order to serve as a cushioning design for pear fruits. Design of experiments and response surface methodology were performed in order to minimize the fruit bruise susceptibility response subject to different spring design parameters. The results revealed that reduced spring pitch and increased coil thickness would significantly minimize bruises of pear fruit. The recycled PET proposed design proved its efficiency in reducing FE pear fruit model bruises by about 50%. This study provides insights on assessing bruise susceptibility using finite element analysis and reusing plastic for fresh produce packaging, thus reducing loops in supply chains and achieving a circular economy.

The main objective of this work is to review the capability of using waste marble dust (MD) particles as reinforcing materials in recycled polymeric composites to achieve environmentally friendly materials. In the present study, polymer composites were fabricated from recycled polyethylene terephthalate (rPET) and MD and then analyzed for their structural and thermal properties. Preparation of rPET-based composites containing 0–20 wt% MD was carried out through extrusion and injection molding. For their characterization Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and dynamic mechanical analysis (DMA) were applied. The DSC analysis revealed a nucleating effect of MD on rPET, which was manifested in a higher crystallization temperature (196.7 °C ⇒ 204.4 °C); however, the marble particles were also found to hamper chain mobility, thereby decreasing the crystallinity ratio (23.7 % ⇒ 19.2 %) of rPET and altering its crystalline structure. According to the TGA measurements, a slight increase occurred in the thermal stability of rPET, its major decomposition temperature increased from 446 °C to 451 °C when 20 wt% MD was incorporated into it. DMA showed an improved stiffness in the entire investigated temperature range for MD-filled composites versus neat rPET. Additionally, several factors were derived from the DMA data, including the effectiveness factor, degree of entanglement, and reinforcing efficiency factor which all suggested a decent interaction between the components indicating a proper reinforcing ability of marble powder. However, above 5 wt% MD content the reinforcing efficiency deteriorated due to the agglomeration of filler particles, which was also supported by scanning electron microscopic images.

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, a comparative life cycle assessment of three different products with reusable and single-use packaging for fresh food distribution was conducted. For the reusable packaging, one utilized a vacuum insulation panel (VIP) box made of recycled polyethylene terephthalate (r-PET), while the other employed expanded polyethylene (EPE). For comparison, a disposable box made of widely used expanded polystyrene (EPS) was selected. We analyzed the environmental impacts of production, transportation, reprocessing (reused boxes), and disposal in 18 impact categories. As a result of analyzing the actual reuse of 300 rounds of fresh food, the cumulative global warming potential (GWP) values of the VIP and EPE box were 136.58 kg carbon dioxide (CO2) eq and 281.72 kg CO2 eq, respectively, 87% and 74% lower than those of the EPS box. Additionally, the GWP values were the same as those of the EPS boxes when the VIP and EPE boxes were reused 7 and 12 times, respectively. The best-case scenario was revealed when the reusable packaging with the r-PET VIP was compared with the EPE and EPS boxes. In conclusion, reusable packaging is expected to contribute to the reduction in the environmental burden and better suit global environmental requirements for sustainable food distribution and related industries. In addition, our findings can inform policy and industry decisions to promote more sustainable practices in the food industry, contributing to the advancement of sustainability in this field. [ABSTRACT FROM AUTHOR]

Background. In textile production, improving the physical and mechanical properties and durable coloring of products is relevant. Purpose. To study the possibility of dyeing PET fibers based on masterbatches from VPET alcoholysis products and to study the physicochemical and technological properties of Pre Oriented Yarn (POY) fiber. Methodology. Moisture absorption (GOST 10681-75), density (tex, calibrated weight (XB-620), specific tensile strength (cN/tex) (ASTM D1294, according to CND-16/0414, PROWHITE laboratory, Istanbul, Turkey), GOST were studied 6611.0.1.2-73 The percentage of fiber grease was determined in a YG981-III Fiber Grease Shredder, tested according to GB/T 6504-2008. Originality. The possibility of using modified masterbatches based on VPET alcoholysis products for dyeing threads has been shown. Findings. It is shown that the values of the indicators of relative strength, elongation at break, the proportion of lubricant, punta are comparable. In the case of using black masterbatch, it was found that in order to improve the color saturation, it is necessary to increase the concentration of the masterbatch. [ABSTRACT FROM AUTHOR]

Sustainable composites based on blends from polypropylene (PP) and recycled polyethylene terephthalate (RPET) and wood flour (WF) were prepared under industry‐relevant conditions by melt extrusion, followed by continuous drawing through spinnerets. Maleic anhydride grafted polypropylene (PP‐g‐MA) was employed to improve the compatibility between matrix and WF. The effects of incorporation of WF and RPET microstructure on the morphological features, rheological measurements, and mechanical properties were investigated. The drawing process converted elliptical RPET phase into highly oriented microfibrillar structure, as characterized by means of scanning electron microscopy (SEM). The highly oriented blend (HOB) represented nonterminal behavior due to the presence of physical networks and enhanced surface area of microfibers for chemical interactions. The tensile strength of neat PP increased by the addition of WF and the existence of microfibrillar RPET phase, whereas the microstructure of RPET had more pronounce effect. The tensile strength and elastic modulus of PP reinforced by WF and oriented RPET improved by 65% and 92%, respectively, demonstrating the high potential of this environmental‐friendly reinforcement method to intensify the mechanical properties of PP. [ABSTRACT FROM AUTHOR]

In the present study, a thermoplastic-reinforced composite filament for 3D printing applications was created by mixing short glass fibers (SGF) with the thermoplastic matrix made from plastic waste. Short glass fiber-reinforced recycled high-density polyethylene (rHDPE) and recycled polyethylene terephthalate (rPET) blend thermoplastic composite filaments were first prepared by a plastic extrusion machine. The produced filaments' physical, mechanical, and thermal properties were investigated. After achieving the desired filament, a 3D printing technology called material extrusion was utilized to create 3D sample parts. The mechanical properties of each printed sample were analyzed following ASTM standards, and their morphological structures were also studied at various weight percentages (pure rHDPE, rHDPE/rPET (75/25 %), rHDPE/rPET reinforced with 15 % SGF, and rHDPE/rPET reinforced with 30 % SGF wt%). From the study, a 52 % increase in tensile strength, 32 % in Young's modulus, and a 50 % reduction in elongation with the addition of 30 wt% of SGF to rHDPE/rPET were noted compared to pure rHDPE. Generally, 3D printable composite filaments can be developed through the incorporation of SGF into plastic waste. This has tremendous advantages for solving environmental pollution and achieving sustainable development.

Copyright of China Plastics / Zhongguo Suliao is the property of Journal Office of CHINA PLASTICS and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Plastic packaging waste, such as polyethylene terephthalate (PET) has increased significantly in recent decades, arousing a considerable and serious public concern regarding the environment, economy, and policy. Plastic recycling is a useful tool to mitigate this issue. Here, a feasible study was performed to investigate the potential of a novel method for identifying virgin and recycled PET. Ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) was combined with various chemometrics, as a simple and reliable method that achieved a high discrimination rate for 105 batches of virgin PET (v-PET) and recycled PET (r-PET) based on 202 non-volatile organic compounds (NVOCs). Making use of orthogonal partial least-squares discrimination analysis (OPLS-DA) together with non-parametric tests, 26 marker compounds (i.e. 12 intentionally added substances (IAS) and 14 non-intentionally added substances (NIAS) as well as 31 marker compounds (i.e. 11 IAS and 20 NIAS) obtained from positive and combination of positive and negative ionization modes of UPLC-Q-TOF-MS, respectively, were successfully identified. Moreover, 100% accuracy was obtained using a decision tree (DT). Cross-discrimination based on misclassified samples using various chemometrics allowed the prediction accuracy to be improved and to identify a large sample set, thus greatly enhancing the application scope of this method. The possible origins of these detected compounds can be the plastic itself, as well as contamination from food, medicine, pesticides, industry-related substances, and degradation and polymerization products. As many of these compounds are toxic, especially those pesticide related, this indicates an urgent requirement for closed loop recycling. Overall, this analytical method provides a quick, accurate, and robust way to distinguish virgin from recycled PET and thus addresses the issue of potential virgin PET adulteration thereby detecting fraud in the area of PET recycling. [ABSTRACT FROM AUTHOR]

There was a dearth of research into the behavior of eccentric RC columns reinforced with fibers, particularly recycled plastic fiber (RF) reinforced columns. The effect of employing end hooked steel fiber (EF) and RF on the performance of eccentric columns was explored in this experiment. Under compressive eccentric load, eight RC columns of 150 × 150 × 1000 mm with a 2% longitudinal reinforcement ratio were tested up to failure. The ratio of load eccentricity to column dimension was 15%. The fiber content (Vf) was variable. Both EF and RF had a Vf of 1%, 2%, and 3%. The applied load was recorded axial/lateral displacement and transverse/longitudinal reinforcement strain. The ultimate load (Pu), ultimate displacement, yield load, stiffness, and ductility index (∆) were all calculated to investigate column behavior. Results showed that adding fibers prevented the concrete cover separation hence prevented the sudden failure as it happened in the control column without fiber (P0). 1% RF and 2% EF enhanced Pu by 10.4% and 34.8%, respectively, while fiber content 3% decreased Pu. Stiffness of columns containing 1% RF and 2% EF was 16.3% and 33.8% higher than that of P0, respectively. The use of 1% and 2% EF delayed yield load, resulting in improved column performance. All fiber contents significantly improved ductility, with enhancement rates ranging from 4.2% with 3% RF to 146.2% with 3% EF. Also, use of 1% RF increased ductility by 70.6%. [ABSTRACT FROM AUTHOR]

This research works with the optimal design of marble dust-filled polymer composites using a multi-criteria decision-making (MCDM) technique. Polylactic acid (PLA) and recycled polyethylene terephthalate (rPET)-based composites containing 0, 5, 10, and 20 wt% of marble dust were developed and evaluated for various physicomechanical and wear properties. The results showed that the incorporation of marble dust improved the modulus and hardness of both PLA and rPET. Moreover, a marginal improvement in flexural strength was noted while the tensile and impact strength of the matrices were deteriorating due to marble dust addition. The outcomes of wear analysis demonstrated an improvement in wear resistance up until 10 wt% filler reinforcement, after which the incidence of dust particles peeling off from the matrix was observed, thereby reducing its efficiency. The best tensile modulus of 3.23 GPa, flexural modulus of 4.39 GPa, and hardness of 83.95 Shore D were obtained for 20 wt% marble dust-filled PLA composites. The lowest density of 1.24 g/cc and the highest tensile strength of 57.94 MPa were recorded for neat PLA, while the highest impact strength of 30.94 kJ/m2 was recorded for neat rPET. The lowest wear of 0.01 g was obtained for the rPET containing 5 wt% marble dust content. The experimental results revealed that for the examined criteria, the order of composite preference is not the same. Therefore, the optimal composite was identified by adopting a preference selection index-based MCDM technique. The findings demonstrated that the 10 wt% marble dust-filled PLA composite appears to be the best solution with favorable physical, mechanical, and wear properties.

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The CS-rPET electrospun nanofibrous membrane is fabricated from recycled polyethylene terephthalate (rPET) through electrospinning and enhanced with candle soot (CS) to separate oil-water mixtures and emulsions when pre-wetted by oil or water. Using rPET polymers and CS waste reduces the environmental impact of plastic bottle waste and improves its value. The CS-rPET electrospun nanofibrous membrane showed excellent separation performance in oil-water mixtures, achieving over 81.18 % and 71.38 % of separation efficiency through 40 separation cycles after pre-wetting by oil and after washing with ethanol and pre-wetting by water, respectively. The membrane maintained high separation performance after being pre-wetted by oil for water-in-oil emulsions with efficiencies above 99 % and flux exceeding 12,200 L m−2 h−1. Similarly, the efficiencies remained above 98 % for oil-in-water emulsions after being pre-wetted by water, with a flux over 8000 L m−2 h−1. Additionally, the CS-rPET electrospun nanofibrous membrane exhibited high separation efficiencies above 97 % and flux over 14,000 L m−2 h−1 after pre-wetting by oil and 7700 L m−2 h−1 after pre-wetting by water in harsh environmental conditions. Its adaptability of switchable wettability on-demand after pre-wetting by oil or water highlights its potential for a wide range of challenging oil-water separation applications. However, multiple separation cycles, separation efficiency and flux were reduced, indicating the necessity to improve the membrane's efficiency and reduce the chance of water accumulation in multicycle separation. [Display omitted] • The CS-rPET electrospun nanofibrous membrane was made of plastic water bottle and modified with candle soot. • The CS-rPET electrospun nanofibrous membrane exhibited superamphiphilicity after being pre-wetted by oil and water in air. • After 40 separation cycles, separation efficiencies were higher than 98 % for water-in-oil and oil-in-water emulsions • The membranes exhibited high performance of oil-water separation in harsh conditions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Samples of rPET were analysed with a non-targeted screening method. • Plasticisers were widely detected in China rPET. • Suggested list of surrogates suitable for China was proposed. • High-throughput detection method was established to analyze surrogates. Waste PET is utilized to produce recycled PET (rPET) through bottle-to-bottle recycling in order to reduce environmental pollution. However, non-intentionally added substances (NIAS) may be generated during rPET production, potentially posing a threat to food safety. In this study, a non-target screening of 13 batches with a total of 39 rPET samples was performed using GC-QTOF-MS and 240 compounds were tentatively identified. It was worth noting that the detection of phthalate esters in rPET from China, such as bis(2-ethylhexyl) phthalate, exhibits a higher diversity (17 different types) and frequency (7.8 %–100 %) in comparison with related studies. Subsequently, based on the principles for selection of surrogates used in challenge test, seven molecular descriptors were selected as variables for compound characterization, followed by principal component analysis (PCA) for representation. Based on this analysis and referencing the EFSA and FDA surrogate suggestion lists, eight surrogates were proposed for China, namely chlorobenzene, toluene, benzophenone, bis(2-ethylhexyl) terephthalate, methyl salicylate, methyl stearate, 1-phenyldecane and phenylcyclohexane. High-throughput detection methods were developed for each surrogate with the regression correlation coefficients over 0.999, spiked recoveries ranging from 99.3-107.5 %, LODs of 0.003–2.192 ng/mL, LOQs of 0.009–7.306 ng/mL, RSD of 0.71–4.23 %, respectively. This research provides foundational data and methodological support for the evaluation of rPET challenge testing in China, offering technical support for subsequent safety assessments of rPET. [ABSTRACT FROM AUTHOR]

Heterojunctions based on ZnO multipod and BiOBr were developed on the floating recycled polyethylene terephthalate (PET) and they were used to investigate the photocatalytic degradation of hexane in water emulsion. Characterizations of the synthesized ZnO-BiOBr-PET photocatalysts was performed using XRD, FESEM, EDX, BET/BJH, FTIR, UV-Vis DRS, PL, WCA, and CV analyses. The FESEM results demonstrated that ZnO multipods have been synthesized during the very short time of microwave heating that effectively hosted the highly dispersed BiOBr nanoplates, particularly in the 15 %ZnO-5 %BiOBr-80 %PET sample. The BET/BJH analysis revealed the low surface areas for the synthesized samples, however, the sample with the highest ZnO multipod loading (15 %ZnO-5 %BiOBr-80 %PET) exhibited slightly enhanced surface area due to the highly dispersed BiOBr over the ZnO multipods. The fabricated samples displayed hydrophobicity and liquid marble like behaviour due to the presence of PET, while the variations in the percentages of ZnO and BiOBr strongly influenced the water contact angle. The formation of heterojunction between ZnO multipod and BiOBr was confirmed which lead to a shift in the visible light region, increased the light harvesting, and also reduced the charge carrier recombination in the composite sample of 15 %ZnO-5 %BiOBr-80 %PET. The ZnO-BiOBr-PET photocatalysts were tested for the photocatalytic degradation of hexane in a water emulsion and results indicated that 15 %ZnO-5 %BiOBr-80 %PET could degrade 92.1 % of initial hexane, retaining its performance over four successive runs with only an 11.7 % decrease in activity. Scavenger tests revealed that, in addition to hydroxyl radicals, superoxide also played a significant role in the photocatalytic degradation of hexane. This obervations indicate the efficient capturing and utilizing of O 2 by this LMP even in non-oxygenated conditions. ● Synthesis of ZnO tetrapod using a rapid and efficient microwave-assisted heating method. ● Synthesis of ZnO tetrapod-BiOBr on recycled PET as a floating photocatalyst. ● Enhanced dispersion of BiOBr on ZnO tetrapod arms and their coverage on recycled PET. ● 92.1 % removal of hexane from water using ZnO-BiOBr-PET floating photocatalyst. ● A mechanism for the photocatalytic degradation of hexane in water based on scavengers. [ABSTRACT FROM AUTHOR]

In this work, Coca-Cola® bottles were reused as a PET polymer (rPET) source to produce electrospun polymeric nanofibers. The nanofibers were electrospun from polymer solutions with different concentrations of reduced graphene oxide (rGO) incorporated for applications in somatosensory electrical stimulation. The rPET/rGO nanofiber mats were characterized by SEM, TEM, Raman, DSC, TGA, and DMA and the results showed that the incorporation of rGO in electrospun rPET fibers produced rPET/rGO composites. The rPET/rGO composites were then evaluated for possible application as dry electrodes. Moreover, with a preliminary test of numerous volunteers, the rPET/rGO dry electrode showed promising results. The rPET/rGO electrodes showed good performance and applicability to make dry electrodes, and these have applications as dry or wearable electrodes to produce electrochemical sensors. [ABSTRACT FROM AUTHOR]

The current paper presents the results of a study on the processing and characterization of waste marble powder‐reinforced recycled polyethylene terephthalate (rPET) composites. Samples with up to 20 wt% marble dust (MD) content were produced with twin‐screw extrusion followed by injection molding. Subsequently, the morphological and mechanical features and the wear resistance of the developed composites were studied. In terms of mechanical properties, the incorporation of MD steadily improved both the tensile and flexural modulus of rPET, while the strength values showed an optimum at 2.5–5.0 wt%, depending on the mode of loading. Above the optimal MD concentration, the strength values deteriorated, however, even at maximum (20 wt%) marble content they were still similar to that of neat rPET, which proves the potential of utilizing waste MD in this specific polymer as filler material. The surface hardness of the fabricated samples also gradually improved with higher marble content, yet it came at the cost of impact toughness. The analysis of wear performance revealed an increasing resistance against wear up to 5.0 wt% filler loading, above which the dust particles got easily peeled off from the matrix, decreasing its efficiency. [ABSTRACT FROM AUTHOR]

"Concrete with numerous short irregular separate low and high modulus fiber is one amongst the distinctive and elite exhibition concrete. Advancement of such substantial builds the wide use of fiber designed up concrete in several framework applications. during this beta review, low modulus and high modulus filaments are used to foster the crossover fiber supported cement. Steel fiber is taken as high modulus fiber and plastic, reused polythene terephthalate fiber is taken as an occasional modulus fiber. completely 10 blends were used for examination together with ancient cement. Three mono fiber blends created utilizing steel, polypropene and reused polythene terephthalate strands with 0.5% volume half. Six crossover fiber utilizing steel fiber and polypropene fiber with 3 distinct volume division and steel fiber and reused polythene terephthalate fiber with 3 distinctive volume portion was utilised being scrutinized. mix in with 0.25% volume portion steel fiber and 0.25% volume division polypropene fiber show higher compared to totally different blends.". [ABSTRACT FROM AUTHOR]

Multiresponsive materials with reversible and durable characteristics are indispensable because of their promising applications in environmental change detections. To fabricate multiresponsive materials in mass production, however, complex reactions and impractical situations are often involved. Herein, a dual responsive (light and pH) spiropyran-based smart sensor fabricated by a simple layer-by-layer (LbL) assembly process from upcycled thermoplastic polyester elastomer (TPEE) materials derived from recycled polyethylene terephthalate (r-PET) is proposed. Positively charged chitosan solutions and negatively charged merocyanine-COOH (MC-COOH) solutions are employed in the LbL assembly technique, forming the chitosan-spiropyran deposited TPEE (TPEE-CH-SP) film. Upon UV irradiation, the spiropyran-COOH (SP-COOH) molecules on the TPEE-CH-SP film undergo the ring-opening isomerization, along with an apparent color change from colorless to purple, to transform into the MC-COOH molecules. By further exposing the TPEE-CH-MC film to hydrogen chloride (HCl) and nitric acid (HNO 3 ) vapors, the MC-COOH molecules can be transformed into protonated merocyanine-COOH (MCH-COOH) with the simultaneous color change from purple to yellow., (© 2024 The Author(s). Small published by Wiley‐VCH GmbH.)

This work explores a novel blend of recycled polyethylene terephthalate/polyamide 11 (rPET/PA11). The blend of rPET/PA11 was introduced to enhance the mechanical properties of rPET at various ratios. The work's main advantage was to utilize rPET in thermoplastic form for various applications. Three different ratios, i.e. 10, 20 and 30 wt.% of PA11 blend samples, were prepared using a twin-screw extruder and injection moulding machine. The mechanical properties were examined in terms of tensile, flexural and impact strength. The tensile strength of rPET was improved more than 50%, while the increase in tensile strain was observed 42.5% with the addition of 20 wt.% of PA11. The improved properties of the blend were also confirmed by the flexural strength of the blends. The flexural strength was increased from 27.9 MPa to 48 MPa with the addition of 30 wt.% PA11. The flexural strain of rPET was found to be 1.1%. However, with the addition of 10, 20 and 30 wt.% of PA11, the flexural strain was noticed as 1.7, 2.1, and 3.9% respectively. The impact strength of rPET/PA11 at 20 wt.% PA11 was upsurged from 110.53 to 147.12 J/m. Scanning electron microscopy analysis revealed a dispersed PA11 domain in a continuous rPET matrix morphology of the blends. This work practical implication would lead to utilization of rPET in automobile, packaging, and various industries. [ABSTRACT FROM AUTHOR]

Plastic packaging materials represent a new class of low‐cost and sustainable additive manufacturing feedstocks. Recycled polyethylene terephthalate (PET) has been shown to be a robust material for material extrusion additive manufacturing, with mechanical properties comparable with acrylonitrile‐butadiene‐styrene. However, due to PET's high crystallinity, it is generally a brittle material and can be subject to premature fracture. It is well known that the addition of rubbers can serve to toughen PET. In this work, micronized rubber powder, as well as non‐reactive and functionalized styrene‐ethylene‐butadiene‐styrene (SEBS) elastomers were compounded with recycled PET. Tensile strength was not significantly affected, but toughness increased 85% with the addition of 5 wt% rubber, 350% with SEBS and over 550% with maleic anhydride functionalized SEBS compared to neat recycled PET. Fracture surface analysis revealed evidence of ductile fracture and cavitation in the rubber toughened samples. Published 2020. This article is a U.S. Government work and is in the public domain in the USA [ABSTRACT FROM AUTHOR]

To solve the decrease in the crystallization, mechanical and thermal properties of recycled polyethylene terephthalate (rPET) during mechanical recycling, the aromatic amide fatty acid salt nucleating agents Na-4-ClBeAmBe, Na-4-ClBeAmGl and Na-4-ClAcAmBe were synthesized and the rPET/nucleating agent blend was prepared by melting blending. The molecular structure, the thermal stability, the microstructure and the crystal structure of the nucleating agent were characterized in detail. The differential scanning calorimetry (DSC) result indicated that the addition of the nucleating agent improved the crystallization temperature and accelerated the crystallization rate of the rPET. The nucleation efficiencies ( NE ) of the Na-4-ClBeAmBe, Na-4-ClBeAmGl and Na-4-ClAcAmBe were increased by 87.2%, 87.3% and 41.7% compared with rPET which indicated that Na-4-ClBeAmBe and Na-4-ClBeAmGl, with their long-strip microstructures, were more conducive to promoting the nucleation of rPET. The equilibrium melting points (Tm0) of rPET/Na-4-ClBeAmBe, rPET/Na-4-ClBeAmGl and rPET/Na-4-ClAcAmBe were increased by 11.7 °C, 18.6 °C and 1.9 °C compared with rPET, which illustrated that the lower mismatch rate between rPET and Na-4-ClBeAmGl (0.8% in b-axis) caused Na-4-ClBeAmGl to be the most capable in inducing the epitaxial crystallization and orient growth along the b-axis direction of the rPET. The small angle X-ray diffraction (SAXS) result proved this conclusion. Meanwhile, the addition of Na-4-ClBeAmGl caused the clearest increase in the rPET of its flexural strength and heat-distortion temperature ( HDT ) at 20.4% and 46.7%.

In the current study, the compatibilization of polypropylene/recycled polyethylene terephthalate (PP/r-PET) blends with different percentages of maleic anhydride (PP-g-MA) was examined. Exploited resource for r-PET was used as water bottles. Specimens of PP/r-PET blends in different percentages, i.e., 90/10, 70/30, and 50/50 were prepared in a corotating twin-screw extruder to evaluate the mechanical properties. Results indicated that PP-g-MA improved compatibilization of the PP/r-PET blends (modulus of elasticity and yield stress were enhanced to about 1450 MPa and 30 MPa) and also enhanced the morphological and mechanical properties. By adding about 2% of the compatibilizer into specimens containing 10% of r-PET, the highest enhancement in mechanical properties was achieved. Besides, both yield strength and the impact of energy were improved 8.3% and 24.6% by increasing the amount of 50% and 10% r-PET in the system. Also, results showed that specimens have higher yield stress and modulus of elasticity after 10 days compared to those specimens without aging due to the presence of stronger interaction after a period of time. [ABSTRACT FROM AUTHOR]

Recycled poly(ethylene terephthalate) (r-PET) is a thermoplastic polyester. Repeated heat processing of r-PET may negatively affect physical properties due to thermal degradation. Therefore, to improve the physical properties of r-PET, poly(glycidyl methacrylate) (PGMA) samples with different molecular weights (low, medium, and high) were synthesized using atom transfer radical polymerization. The synthesized PGMA polymer was then subjected to 1H-NMR characterization and gel permeation chromatography for the analysis of molecular weight and its distribution. The intrinsic viscosity values of the r-PET/PGMA blend were increased from 0.61 to 0.8 dL g− 1 using high-molecular-weight PGMA at 2 wt%, and the glass transition temperature was increased from 71.8 °C for r-PET to 82.2 °C using high-molecular-weight PGMA at 1 wt%. Young's modulus was increased by 1.1 times using 2 wt% high-molecular-weight PGMA compared with raw r-PET. All r-PET/PGMA blends samples exhibited notable shear thinning behavior and high viscosity compared with raw r-PET, and r-PET/PGMA blends are found with medium-molecular-weight PMGA polymers observing optimal physical properties. With these enhanced properties, the r-PET/PGMA blends can be applied in the recycling of PET, such as in eco-friendly yarn, packaging materials, and melt-brown non-woven fabric applications. [ABSTRACT FROM AUTHOR]

Plastics are versatile materials used in a variety of sectors that have seen a rapid increase in their global production. Millions of tonnes of plastic wastes are generated each year, which puts pressure on plastic waste management methods to prevent their accumulation within the environment. Recycling is an attractive disposal method and aids the initiative of a circular plastic economy, but recycling still has challenges to overcome. This review starts with an overview of the current European recycling strategies for solid plastic waste and the challenges faced. Emphasis lies on the recycling of polyolefins (POs) and polyethylene terephthalate (PET) which are found in plastic packaging, as packaging contributes a signification proportion to solid plastic wastes. Both sections, the recycling of POs and PET, discuss the sources of wastes, chemical and mechanical recycling, effects of recycling on the material properties, strategies to improve the performance of recycled POs and PET, and finally the applications of recycled POs and PET. The review concludes with a discussion of the future potential and opportunities of recycled POs and PET.

The main objective of this work is to review the capability of using waste marble dust (MD) particles as reinforcing materials in recycled polymeric composites to achieve environmentally friendly materials. In the present study, polymer composites were fabricated from recycled polyethylene terephthalate (rPET) and MD and then analyzed for their structural and thermal properties. Preparation of rPET-based composites containing 0-20 wt% MD was carried out through extrusion and injection molding. For their characterization Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and dynamic mechanical analysis (DMA) were applied. The DSC analysis revealed a nucleating effect of MD on rPET, which was manifested in a higher crystallization temperature (196.7 °C ⇒ 204.4 °C); however, the marble particles were also found to hamper chain mobility, thereby decreasing the crystallinity ratio (23.7 % ⇒ 19.2 %) of rPET and altering its crystalline structure. According to the TGA measurements, a slight increase occurred in the thermal stability of rPET, its major decomposition temperature increased from 446 °C to 451 °C when 20 wt% MD was incorporated into it. DMA showed an improved stiffness in the entire investigated temperature range for MD-filled composites versus neat rPET. Additionally, several factors were derived from the DMA data, including the effectiveness factor, degree of entanglement, and reinforcing efficiency factor which all suggested a decent interaction between the components indicating a proper reinforcing ability of marble powder. However, above 5 wt% MD content the reinforcing efficiency deteriorated due to the agglomeration of filler particles, which was also supported by scanning electron microscopic images., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

The aim of this work is to evaluate the feasibility of small punch test as a tool for analysing the mechanical response of small plastic parts or specimens. Here, the small punch test was used to study the possible influence of ultraviolet radiation exposure on the mechanical properties of outdoor furniture made from recycled polyethylene terephthalate in the frame of an industrial project with participants from both industry and academia. The industrial project partners prepared four types of masterbatches in order to stabilize the recycled polyethylene terephthalate and to minimize photodegradation as well as colour change in the final product. The masterbatches contained red pigments, antioxidants and ultraviolet absorbers. Flat sample plates were injection moulded from recycled polyethylene terephthalate and these masterbatches. Some sample plates were used as-moulded, some samples received a thermal treatment in order to post-crystallize the bottle-grade recycled polyethylene terephthalate and some other samples were subjected to ultraviolet radiation for 900 h. In the frame of an industrial project, the ultraviolet ageing was performed superficially only on one side of the plates in order to evaluate the colour change. The three sets of samples were analysed by means of tensile tests, differential scanning calorimetry and intrinsic viscosity. However, the irradiated samples could not be tested with tensile tests due to their small size. Therefore, the small punch test was used to accurately characterize these small samples. The feasibility of the small punch test as a valid mechanical characterization method for these types of materials was demonstrated by comparing the small punch test results from the unradiated samples with the tensile test ones. The mechanical parameters obtained from both types of tests showed the same results. Although the used industrial ultraviolet ageing process produced a colour change in the studied recycled polyethylene terephthalate samples, it was possible to verify via small punch tests that the mechanical properties were not affected. [ABSTRACT FROM AUTHOR]

In this research, the mechanical and thermal properties of nanocomposites containing alumina nanoparticles in the high-density polyethylene/recycled polyethylene terephthalate/maleic anhydride polyethylene (HDPE/rPET/MAPE) matrix were investigated. For this purpose, tensile, flexural, impact energy, and differential scanning calorimetry (DSC) test were done. Here, 0, 1, 3, and 5 wt% alumina nanoparticles were added to the HDPE/rPET/MAPE using a co-rotating screw extruder. Morphological studies using scanning electron microscopy revealed that alumina nanoparticles within HDPE/rPET/MAPE matrix were well dispersed in low content of nanoparticles (up to 3 wt%). The results of mechanical tests showed that the presence of alumina nanoparticles improved tensile strength, elastic modulus, flexural strength, and impact energy. The maximum improvement was observed for the sample containing 3 wt% of alumina. DSC test revealed alumina nanoparticles in the content of 3 wt% increased the crystallinity degree of HDPE in the blend of HDPE/rPET/MAPE and caused to approach the melting points of HDPE and rPET. [ABSTRACT FROM AUTHOR]

The use of virgin and recycled plastic macro fibers as reinforcing elements in construction materials has recently gained increasing attention from researchers. Specifically, recycled fibers have become more attractive owing to their large-scale availability, negligible cost, and low environmental footprint. In this work, we investigate the benefits related to the use of fully-recycled synthetic fibers as dispersed reinforcement in Fiber Reinforced Cement Composites (FRCCs). In light of the reference performance of FRCCs including virgin polypropylene (PP) fibers only, the mechanical response of composites reinforced with polyolefin filaments treated with a sol-gel silica coating and polyethylene terephthalate (PET)/polyethylene (PE) cylindrical draw-wire fibers is here assessed through three-point bending tests. Remarkably, recycled polyolefins lead to a notable enhancement in terms of peak strength and post-crack energy dissipation capability. This improvement is ascribed to both the flattened shape of fibers and the surface coating, which turns out to be very effective at strengthening the fiber-to-matrix bond. On the other hand, PET/PE fibrous reinforcement generally leads to a lower toughness, if compared to the virgin fibers. However, no reduction in terms of peak stress is evidenced. Balancing the significance of mechanical performance and environmental sustainability in the framework of a circular economy approach, both fully-recycled fibers at hand can be regarded as promising candidates for innovative structural applications.

In the present study, a thermoplastic-reinforced composite filament for 3D printing applications was created by mixing short glass fibers (SGF) with the thermoplastic matrix made from plastic waste. Short glass fiber-reinforced recycled high-density polyethylene (rHDPE) and recycled polyethylene terephthalate (rPET) blend thermoplastic composite filaments were first prepared by a plastic extrusion machine. The produced filaments' physical, mechanical, and thermal properties were investigated. After achieving the desired filament, a 3D printing technology called material extrusion was utilized to create 3D sample parts. The mechanical properties of each printed sample were analyzed following ASTM standards, and their morphological structures were also studied at various weight percentages (pure rHDPE, rHDPE/rPET (75/25 %), rHDPE/rPET reinforced with 15 % SGF, and rHDPE/rPET reinforced with 30 % SGF wt%). From the study, a 52 % increase in tensile strength, 32 % in Young's modulus, and a 50 % reduction in elongation with the addition of 30 wt% of SGF to rHDPE/rPET were noted compared to pure rHDPE. Generally, 3D printable composite filaments can be developed through the incorporation of SGF into plastic waste. This has tremendous advantages for solving environmental pollution and achieving sustainable development., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)

In this study, polyethylene terephthalate‐based waste drinking bottles have been used to develop colorful nanofibers via electrospinning. The recycled polyethylene terephthalate (r‐PET) nanofibers were characterized through scanning electron microscopy (SEM), Fourier transform infra red spectroscopy (FTIR), X‐ray diffraction (XRD), and X‐ray photo electron spectroscopy (XPS) techniques and were explored for advanced colorful applications. To prepare colorful r‐PET nanofibers, two different disperse dyes, C.I Disperse Blue 56 (DB‐56) and C.I Disperse Red 167:1 (DR 167:1), were used by dope dyeing technique. The dope dyeing of r‐PET nanofibers was optimized by determining the effects of different polymer concentrations (9%–15%) and dye concentrations (1%–7%). The proposed r‐PET nanofibers offer many advantages such as good color fastness, good mechanical strength, save processing energy, and time compared to other conventional nanofibers. [ABSTRACT FROM AUTHOR]

This research works with the optimal design of marble dust-filled polymer composites using a multi-criteria decision-making (MCDM) technique. Polylactic acid (PLA) and recycled polyethylene terephthalate (rPET)-based composites containing 0, 5, 10, and 20 wt% of marble dust were developed and evaluated for various physicomechanical and wear properties. The results showed that the incorporation of marble dust improved the modulus and hardness of both PLA and rPET. Moreover, a marginal improvement in flexural strength was noted while the tensile and impact strength of the matrices were deteriorating due to marble dust addition. The outcomes of wear analysis demonstrated an improvement in wear resistance up until 10 wt% filler reinforcement, after which the incidence of dust particles peeling off from the matrix was observed, thereby reducing its efficiency. The best tensile modulus of 3.23 GPa, flexural modulus of 4.39 GPa, and hardness of 83.95 Shore D were obtained for 20 wt% marble dust-filled PLA composites. The lowest density of 1.24 g/cc and the highest tensile strength of 57.94 MPa were recorded for neat PLA, while the highest impact strength of 30.94 kJ/m2 was recorded for neat rPET. The lowest wear of 0.01 g was obtained for the rPET containing 5 wt% marble dust content. The experimental results revealed that for the examined criteria, the order of composite preference is not the same. Therefore, the optimal composite was identified by adopting a preference selection index-based MCDM technique. The findings demonstrated that the 10 wt% marble dust-filled PLA composite appears to be the best solution with favorable physical, mechanical, and wear properties. [ABSTRACT FROM AUTHOR]

A comparison was performed on various methods detecting the volatile contaminants (VCs) in recycled poly(ethylene terephthalate) (rPET) flakes, the results demonstrated that head-space solid phase micro-extraction combined with comprehensive two-dimensional gas chromatograph-tandem quadrupole-time-of-flight mass spectrometry (HS-SPME-GC×GC–QTOF-MS) was a sensitive, effective, accurate method, and successfully applied to analyze 57 rPET flakes collected from different recycling plants in China. A total of 212 VCs were tentatively identified, and the possible source were associated with plastic, food, and cosmetics. 45 VCs are classified as high-priority compounds with toxicity level IV or V and may pose a risk to human health. Combined chemometrics for further analysis revealed that significant differences among these three geographical recycling regions. 6, 7, and 6 volatile markers were chosen based on VIP values and S-plot among plant1 plant 2 and plant 3, respectively. The markers differed significantly between recycled rPET samples in three geographical recycling regions based on chemometrics analysis. The initial classification rate and cross-validation accuracy were 100% on the identified VCs. These significant differences demonstrate that a systematic study is needed to obtain a comprehensive data on the contamination of rPET for food contact applications in China. [Display omitted] • Three GC-based techniques were compared to study volatile contaminants in rPET. • HS-SPME-GC×GC-QTOF-MS identified the most volatile contaminants in effective manner. • The potential origin of these volatile contaminants was suggested. • 45 volatile contaminants with high concerns for the public health were discovered. • The region from which rPET originates was predicted with 100% accuracy. [ABSTRACT FROM AUTHOR]

This paper studied the mechanical properties and durability of plastic mortar made with recycled Polyethylene Terephthalate (PET). The effects of gradation and admixtures, including bitumen, fly ash, and nano-calcium carbonate, on strength were investigated. The temperature stability was studied based on the compressive strength at different temperatures. The water absorption and sulfate corrosion resistance were conducted to evaluate the durability. The microstructure of the plastic mortar was observed by Scanning Electron Microscope (SEM). The test results show that increasing the content of fine particles could first increase and then decrease the strength. Partially replacing PET with bitumen and/or fly ash could significantly influence the strength. But the nano-calcium carbonate had no significant effect on strength. The plastic mortar had high stability as temperature changed from 30 to 90 °C. The strength was similar for specimens under different testing temperatures. The plastic mortar had very low water absorption and high sulfate corrosion resistance. The SEM results revealed that the PET and aggregates were bonded well. [ABSTRACT FROM AUTHOR]

Polyethylene terephthalate food-product containers made with post-consumer materials have been found contaminated with heavy metals due to the recycling and sorting process. The increased use of recycled plastic flake from international suppliers, and subsequent commingling with electronic waste, has been suspected as the source of the increased levels of heavy metal contamination. In this study, nickel, chromium, cadmium, antimony, and lead were quantified in post-consumer polyethylene terephthalate extruded sheet and thermoformed samples, using inductively coupled plasma-atomic emission spectrometry. Recycled polyethylene terephthalate samples were digested using trace-metal grade hydrochloric, perchloric, and nitric acids. Samples were analyzed per ASTM E1613-04, standard test method for determination of lead by inductively coupled plasma atomic emission spectrometry, flame atomic absorption spectrometry, or graphite furnace atomic absorption spectrometry techniques. Two hundred samples were tested of which 29 were found to be contaminated with heavy metals. Chromium and cadmium were found in all 29 sample replicates. Nickel was found in 96.4% of the sample replicates and when it was found, the concentration averaged 11.59 ppm. Lead was found in 90.4% of the sample replicates and the average concentration was 0.15 ppm. Antimony was found in 97.6% of the sample replicates and concentrations were higher in rigid recycled polyethylene terephthalate containers compared to films. It was noted that the total contamination in all 29 samples was well below the threshold level set for the incidental presence of heavy metals in packaging materials as set forth in California’s Toxics in Packaging Prevention Act of 2006. The percentage of each heavy metal that would actually leach from the plastics to contaminate food products during normal processing, packaging, marketing, and consumer use was not determined in this study. [ABSTRACT FROM PUBLISHER]

Abstract: Most plastics collected for recycling from the household waste stream are plastic bottles. The majority of bottles are made from Polyethylene Terephthalate (PET) estimated that the ratio is 55-60%. The objective of this research is to determine optimum quality and the effect usage of recycled PET as partial fine aggregate replacement in modified asphalt mixture by determining the permanent deformation and stiffness behaviour. The modified asphalt mixtures were produced from content concentrate of recycled PET pallet range between 5 and 25% of the weight of asphalt mixture with sieve size from 2.36mm to 1.18mm and 5% weight of bitumen content as follow hot mix asphalt wearing course 14 (ACW14) in Standard Specification of Road Work in Malaysia. The samples were subjected to Repeated Load Axial Test (RLAT) loading for 1800 cycles and axial load applied 100kN at to determine permanent deformation of modified asphalt mixture. The Indirect Tensile Stiffness Modulus Test (ITSM) was used to evaluate stiffness modified asphalt sample at 25°C. The result obtained from the lab testing reveals the maximum permanent deformation of modified asphalt mixture reach at 20% replacement with recycled PET. However the stiffness of PET modified asphalt mixtures tend to decrease compare to unmodified asphalt mixture. The finding indicates that PET has ability to improve permanent deformation properties of asphalt mixture. In the environmental and economical aspects, PET modified asphalt mixture is found suitable to be used for road pavements. [Copyright &y& Elsevier]