Phthalate Plasticizers Research Articles

Multi‐branched octopus‐like plasticizers with excellent plasticizing performance in poly(vinyl chloride)

AbstractThe development of alternatives is a priority issue for the plasticizer industry due to the reproductive toxicity and potential carcinogenicity of phthalate plasticizers. Herein we demonstrate the synthesis and characterization of multi‐branched octopus‐like plasticizers applied in poly(vinyl chloride) (PVC). The plasticizers were achieved through a straightforward one‐step esterification reaction, resulting in four polyol ester plasticizers (glyceryl tri‐n‐octanoate [GTOE], pentaerythritol tetra‐n‐octanoate [PQOE], xylitol penta‐n‐octanoate [XPOE], and mannitol hexa‐n‐octanoate [MHOE]). The multi‐branched structure enhances the interactions between plasticizers and PVC molecules leading to superior plasticizing properties, particularly mechanical properties, thermal stability, and migration resistance compared with commercial plasticizers di(2‐ethylhexyl) phthalate (DEHP), dioctyl terephthalate (DOTP), and acetyl tributyl citrate (ATBC). Concretely, the elongation at break of MHOE/PVC (825%) and PQOE/PVC (814.63%) was better than that of DEHP/PVC (670.02%), DOTP/PVC (490.62%) and ATBC/PVC (566.78%). The T5% of GTOE/PVC, PQOE/PVC, XPOE/PVC, and MHOE/PVC were 46.97, 67.24, 60.09 and 48.14°C higher than ATBC/PVC respectively. In the volatility resistance testing after 48 h, the weight loss of GTOE/PVC, PQOE/PVC, XPOE/PVC, and MHOE/PVC was 5.63%, 3.64%, 2.95%, and 8.88% respectively, which was far less than DEHP/PVC (15.58%), DOTP/PVC (11.83%) and ATBC/PVC (18.15%). Consequently, the obtained plasticizers demonstrate enhanced plasticizing efficiency, presenting promising alternatives to phthalate plasticizers and expanding the repertoire of choices within the plasticizer industry.

Recoverable and reusable light-induced multi-arm azobenzenes-Fe3O4 hybrid sorbent for enrichment of phthalate plasticizer and utilized as a SALDI substrate for the detection of 2-naphthol

The construction, structural identifications along with compositional properties, using TEM, FT-IR, and XPS spectroscopies, of an innovative light-induced multi-arm azobenzenes based Fe3O4 magnetic nanoparticles (Azo-Fe3O4 MNPs) are being reported. Such organic (light-sensitive dendrimers-like structure), inorganic (magnet core), hybrid material has been applied as an efficient recoverable/reusable extractive sorbent for the detection of phthalate plasticizers from acetate buffer solution. The extraction study was controlled within consecutive procedures via UV-light exposure to achieve pore-size control which then further subjected for the evaluation of the analytes’ retention, separation, and release as well as the detection of the phthalate pollutants using GCMS–. Various experimental conditions, such as time of extraction, salt concentration, pH, and desorption time, were studied and adjusted. Additionally, the extraction repeatability (RSD from 0.46 % to 6.12%, n = 5) of the studied sorbent was comparable to other published work. The linear range extended from 6.25 to 100 μg L-¹ and detection limits (LOD) within the range of 41- 150 ng L-1 were achieved, demonstrating good linearity with values ranging from 0.9992 to 0.9892. The inter-batch and intra-batch RSD ranged from 0.46 % to 6.12 %, respectively. Additionally, it provides effective detection of 2-naphthol when used as a SALDI substrate.

Techno-economic assessment of co-production of biodiesel and epoxy fatty acid methyl ester as renewable fuel and plasticizer from waste cooking oil

Diversifying waste cooking oil (WCO)-based biodiesel production towards epoxy fatty acid methyl esters (EFAMEs) offers a double gain, boosting revenue channels in the biodiesel sector and driving the development of sustainable phthalate plasticizer alternatives. This study explored the techno-economic feasibility of co-derived biodiesel and EFAMEs from WCO using a three-step process involving enzymatic transesterification, urea complexation, and performic acid epoxidation. The result shows that a plant processing 61,300 tonnes/year of WCO, may produce ∼27,770 tonnes/year of biodiesel and ∼30,180 tonnes/year of EFAMEs, with a total heating duty of 1,124 kW and annual electricity consumption of 34.9 million kWh. The initial capital investment of the plant in China amounts to 136.8 MM CNY, with an annual manufacturing cost of 460 MM CNY in 2022. Techno-economic evaluation demonstrats a net present value (NPV) of 421.9 MM CNY at a 10 % discount rate, an internal rate of return (IRR) of 37.69 %, and discounted payback period of 2.37 years. The break-even point (BEP) is estimated at an annual sales volume of total products of 27,101 tonnes/year, including 12,790, 11,769, 2,542, and 2,390 tonnes/year of epoxy plasticizers, biodiesel, glycerol, and polymeric grease, respectively, collectively utilizing 42.38 % of the processing capacity. Monte Carlo simulation indicates minimal risk of the project, with probabilities of 98.5 % for IRR > 10 % and 97.8 % for a positive NPV. This study affirms the economic viability of co-producing biodiesel and EFAMEs from WCO for industrial application.

In-silico characterization of a hypothetical protein of Sulfobacillus sp. hq2 for degradation of phthalate diesters

Phthalate plasticizers are hazardous compounds capable of causing endocrine disruption, cancers, and developmental disorders. Phthalate diesters are commonly used plasticizers in plastic products (PVC pipes) that leach out into the environment due to changes in temperature, pressure, and pH, posing harmful effects on different life forms. Bioremediation of phthalate diesters utilizing bacterial esterase has been recognized as an efficient approach but few effective esterases capable of degrading a wide range of phthalate diesters have been identified. Further, the thermostability of these esterases is a highly desirable property for their applications in diverse in-situ conditions. In this present in-silico study a hypothetical protein (POB10642.1) as a high-potential esterase from a thermostable strain of Sulfobacillus sp. hq2 has been characterized. Analysis revealed a significant sequence identity of 42.67 % and structural similarity (RMSD 0.557) with known phthalate diester degrading EstS1 esterase and a high Tm range of 55–66 °C. Structural analysis revealed the presence of two cavities on the surface mediating toward the catalytic site forming a catalytic tunnel. The enzyme POB10642.1 has significant molecular docking binding energies in the range of −5.4 to −7.5 kcal/mol with several phthalate diesters, including Diethyl phthalate, Dipropyl phthalate, Dibutyl phthalate, Dipentyl phthalate, Dihexyl phthalate, Benzyl butyl phthalate, Dicyclohexyl phthalate, and Bis(2-ethylhexyl) phthalate. High stability of binding during 100 ns molecular dynamics simulations revealed efficient and stable binding of the enzyme with a wide range of phthalate diesters at its active site, demonstrating the ability of the identified esterase to interact with and degrade diverse phthalate diesters. Therefore, POB10642.1 esterase can be an efficient candidate to be utilized in the development of enzyme-based bioremediation technologies to reduce the toxic levels of phthalate diesters.

Catalytic revalorization of plastic waste phthalate plasticizers into simple aromatics and alkenes

Catalytic revalorization of plastic waste phthalate plasticizers into simple aromatics and alkenes

Source identification and human exposure assessment of organophosphate flame retardants and plasticisers in soil and outdoor dust from Nigerian e-waste dismantling and dumpsites

Electronic waste (e-waste) dismantling and dumpsite processes are major sources of organophosphate flame retardant and plasticiser emissions and may pose potentially adverse effects on environment and human health. In 20 outdoor dust and 49 soil samples collected from four e-waste dismantling and three e-waste dumpsites in two States of Nigeria (Lagos and Ogun), we identified 13 alternative plasticisers (APs), 7 legacy phthalate plasticisers (LPs), and 17 organophosphorus flame retardants (OPFRs) for the first time in African e-waste streams. In the samples from dismantling sites, the range (median) concentrations of ∑13APs, ∑7LPs, and ∑17OPFRs were 11 to 2747 μg/g (144 μg/g), 11 to 396 μg/g (125 μg/g), and 0.2 to 68 μg/g (5.5 μg), in dust respectively and 1.8 to 297 μg/g (55 μg/g), 1.3 to 274 μg/g (48.5 μg/g), and 1.6 to 62 μg/g (1.6 μg/g), in soil respectively. Results for soil samples from e-waste dumpsites were (6.6 to 195 μg/g (23.7 μg/g), 6.0 to 295 μg/g (54.8), and 0.4 to 42.3 μg/g (9.0 μg/g) for ∑13APs, ∑7LPs, and ∑17OPFRs respectively. Overall, concentrations of APs were significantly higher at the dismantling sites (p = 0.005) compared to dumpsites, levels of LPs were higher at dismantling sites but not significant, while OPFR concentrations were significantly higher in dumpsite samples (p = 0.005). Plasticisers were found to be major contributors to pollution at e-waste dismantling sites, while OPFRs were associated with both automobile dismantling and e-waste dumpsite processes. Following particle size fractionation of selected soil samples, higher concentrations of targeted compounds were observed in the smaller mesh (180 μm) soil sieve fraction. For dust, the total median estimated daily intake via ingestion and dermal adsorption (EDIing and EDIderm) ranged from 43 to 74 ng/kg bw/day and 0.4 to 0.7 ng/kg bw/day, respectively. Correspondingly, 4.6 to 45 ng/kg bw/day and 0.015 to 0.57 ng/kg bw/day were the values found for soil, respectively. According to these results, the targeted chemicals do not appear to pose a non-carcinogenic risk to e-waste workers through ingestion or dermal contact of bio-accessible fractions of the chemicals. Human biomonitoring campaigns are recommended in the Nigerian e-waste environment considering the elevated concentration levels found for the majority of targeted compounds and that risk parameters required for exposure assessment were only available for a limited number of compounds.

Application of solvent-based dissolution for the recycling of polyvinylchloride flooring waste containing restricted phthalate plasticizers

The applicability of a new recycling method for extracting contaminants from polymers, dissolution-based recycling, was tested on a polyvinylchloride equipped with diethylhexyl phthalate, benzylbutyl phthalate, di-isobutyl phthalate, di-n‑butyl phthalate, originating from post-consumer flooring waste. Due to European restrictions on these ortho-phthalate diester-based plasticizers, the mechanical recycling of plasticized polyvinylchloride is no longer feasible. In this study, we have shown that dissolution and consecutive purification of the polymer eliminate 99.9 % of diethylhexyl phthalate's initial concentration at the laboratory scale. The impact of different process parameters, e.g., temperature, agitation, and extraction kinetics, have been tested. The findings were transferred to a technical scale of 5 kg/d, using a multi-step extraction in counter-flow mode. An elimination of 99.4 % of diethylhexyl phthalate initial concentration has been achieved, which fulfills legal requirements. These promising results showed the technical feasibility and served as a preliminary stage for further up-scaling to technical readiness level 6.

Advanced Detection and Electrochemical Sensing of Hazardous Short-Branched Phthalate Plasticizers Using Novel Ga12N12 Nanomaterials: A DFT Study

Advanced Detection and Electrochemical Sensing of Hazardous Short-Branched Phthalate Plasticizers Using Novel Ga12N12 Nanomaterials: A DFT Study

Biochemical and transcriptomic analyses reveal the toxicological response and potential mechanism of butyl benzyl phthalate in zebrafish gills

Butyl benzyl phthalate (BBP), a common phthalate plasticizer, is frequently detected in aquatic environments. However, there has been relatively little research on its effects on gill-related responses. This study exposed adult zebrafish to BBP concentrations ranging from 5 to 500 μg/L for 28 days, specifically investigating its toxicity in the gills. Assessment of oxidative stress biomarkers and gene expression related to apoptosis and mitochondria was conducted. Results demonstrated that exposure to 500 μg/L of BBP disrupted the antioxidant defense system, leading to lipid peroxidation and DNA damage. Moreover, the expression level of the caspase-3 gene exhibited an approximate two-fold increase, whereas the expression of 18rs-rrn decreased by 50 % on day 28. Gene Ontology enrichment analysis indicated suppressed expression of antioxidant and metabolic process terms, alongside inhibition of metabolism, immune, and signal transduction-related pathways. This study offers novel insights into the toxic effects and mechanisms of BBP on fish, providing valuable data for assessing environmental risks linked to BBP contamination and advocating for its management in aquatic ecosystems.

Quantification of additives in beached plastic debris from Aotearoa New Zealand

Plastics have become an essential part of modern society. Their properties can be easily manipulated by incorporating additives to impart desirable attributes, such as colour, flexibility, or stability. However, many additives are classified as hazardous substances. To better understand the risk of plastic pollution within marine ecosystems, the type and concentration of additives in plastic debris needs to be established. We report the quantification of thirty-one common plastic additives (including plasticisers, antioxidants, and UV stabilisers) in beached plastic debris collected across Aotearoa New Zealand. Additives were isolated from the plastic debris by solvent extraction and quantified using high-resolution liquid chromatography-mass spectrometry. Twenty-five of the target additives were detected across 200 items of debris, with plasticisers detected at the highest frequency (99 % detection frequency). Additives were detected in all samples, with a median of four additives per debris item. A significantly higher number of additives were detected per debris item for polyvinyl chloride (median = 7) than polyethylene or polypropylene (median = 4). The additives bis(2-ethylhexyl) phthalate, diisononyl phthalate, diisodecyl phthalate, and antioxidant 702 were detected at the highest concentrations (up to 196,930 μg/g). The sum concentration of additives per debris item (up to 320,325 μg/g) was significantly higher in polyvinyl chloride plastics (median 94,716 μg/g) compared to other plastic types, primarily due to the presence of phthalate plasticisers. Non-target analysis was consistent with the targeted analysis, indicating a higher number and concentration of additives in polyvinyl chloride debris items compared to all other polymer types. Feature identification indicated the presence of more additives than previously detected in the targeted analysis, including plasticisers (phthalate and non-phthalate), processing aids, and nucleating agents. This study highlights phthalates and polyvinyl chloride as key targets for consideration in ecotoxicology and risk assessments, and the development of policies to reduce the impacts of plastic pollution.

Gas-phase and air-solid interface behavior of phthalate plasticizer and ozone: The influence of indoor mineral dust

Indoor environments serve as reservoirs for a variety of emerging pollutants (EPs), such as phthalates (PAE), with intricate interactions occurring between these compounds and indoor oxidants alongside dust particles. However, the precise mechanisms governing these interactions and their resulting environmental implications remain unclear. By theoretical simulations, this work uncovers multi-functional compounds and high oxygen molecules as important products arising from the interaction between DEP/DEHP and O3, which are closely linked to SOA formation. Further analysis reveals a strong affinity of DEP/DEHP for mineral dust surfaces, with an adsorption energy of 22.11/30.91 kcal mol−1, consistent with a higher concentration of DEHP on the dust surface. Importantly, mineral particles are found to inhibit every step of the reaction process, albeit resulting in lower product toxicity compared to the parent compounds. Thus, timely removal of dust in an indoor environment may reduce the accumulation and residue of PAEs indoors, and further reduce the combined exposure risk produced by PAEs-dust. This study aims to enhance our understanding of the interaction between PAEs and SOA formation, and to develop a fundamental reaction model at the air-solid surface, thereby shedding light on the microscopic behaviors and pollution mechanisms of phthalates on indoor dust surfaces.

Screening for compounds with bioaccumulation potential in breast milk using their retention behavior in two-dimensional gas chromatography

Discovery of emerging pollutants in breast milk will be helpful for understanding the hazards to human health. However, it is difficult to identify key compounds among thousands present in complex samples. In this study, a method for screening compounds with bioaccumulation potential was developed. The method can decrease the number of compounds needing structural identification because the partitioning properties of bioaccumulative compounds can be mapped onto GC×GC chromatograms through their retention behaviors. Twenty pooled samples from seven provinces in China were analyzed. 1,286 compounds with bioaccumulation potential were selected from over 3,000 compounds. Sixty-two compounds, including aromatic compounds, phthalates, and phenolics etc., were identified with a high level of confidence and then quantified. Among them, twenty-seven compounds were found for the first time in breast milk. Three phthalate plasticizers and two phenolic antioxidants were found in significantly higher concentrations than other compounds. A toxicological priority index approach was applied to prioritize the compounds considering their concentrations, detection frequencies and eight toxic effects. The prioritization indicated that 13 compounds, including bis(2-ethylhexyl) phthalate, dibutyl phthalate, 1,3-di-tert-butylbenzene, phenanthrene, 2,6-di-tert-butyl-1,4-benzoquinone, 2,4-di-tert-butylphenol, and others, showed higher health risks. Meanwhile, some compounds with high risk for a particular toxic effect, such as benzothiazole and geranylacetone, were still noteworthy. This study is important for assessing the risks of human exposure to organic compounds.

Maternal phthalate exposure and BMI trajectory in children-an 18-year birth cohort follow-up study.

Obesity is a major health concern worldwide. Previous studies have suggested that phthalate plasticizers are obesogens. However, the relationship between early-life phthalate exposure and long-term obesity development remains unknown. We investigated the association between prenatal phthalate exposure and children's body mass index (BMI) patterns in an 18-year birth cohort follow-up study in Taiwan. Our analytical lab quantified seven phthalate metabolites in maternal urine during pregnancy using quantitative liquid chromatography-tandem mass spectrometry. In addition, we calculated BMI z scores for participated children at each follow-up, utilized trajectory analysis to describe children's BMI z-score patterns at 2-18 years of age, and adopted generalized estimating equations (GEE) and multivariate logistic regression models to assess the association between prenatal phthalate exposure and BMI z scores in children. A total of 208 mother-child pairs were included in the analysis. Maternal urinary diethyl phthalate (DEP) metabolites were associated with the increase of BMI z scores in children aged 2-18 years in the GEE model. Doubled maternal urinary ∑mDEHP (3 mono hexyl-metabolites of di-ethyl-hexyl phthalate (DEHP) increased the risk of children being in the stable-high BMI trajectory group until the age of eighteen. We observed that BMI trajectories of children remained stable after the age of 5 years. During each follow-up, a higher frequency of overweight or obese was observed in children, ranging from 15.9% to 35.6% for girls and 15.2-32.0% for boys, respectively. Prenatal phthalate exposure was associated with increasing BMI z scores in children. Prenatal DEHP exposure was associated with a stable-high BMI trajectory in children up to the age of 18 years.

Occurrence and ecological risk assessment of 16 plasticizers in the rivers and estuaries in Japan

Owing to growing concerns about the adverse effects of phthalate plasticizers, non-phthalate plasticizers are being increasingly used as their replacement. However, information on the residual environmental concentrations and ecological risks posed by these plasticizers is limited. In this study, we analyzed the environmental contamination of 11 phthalates and 5 non-phthalate plasticizers in Class A and B rivers in Japan. In the considered river water samples, phthalates and non-phthalates were detected in the following order of detection frequency: phthalates (DEHP > DMP > DMEP > BBP > DNPP > DNP > DEEP > DBEP = DNOP) and non-phthalates (ATBC > DEHS > DEHA > TOTM = DIBA). Phthalate plasticizers were the most abundant and included DEHP (157–859 ng/L), DMP (<MQL–3680 ng/L), DMEP (<MQL–4600 ng/L), and BBP (<MQL–1080 ng/L); non-phthalates included ATBC (<MQL–1550 ng/L) and DEHS (<MQL–220 ng/L). The risk quotient for DEHP and ATBC was found to be more than one, suggesting an emerging concern regarding their contamination and adverse effects on aquatic organisms. This study is the first to shed light on the persistence of non-phthalate plasticizers in freshwater environments in Japan; the findings could help develop strategies to mitigate the environmental effects of plasticizers.

Extralong hot-spots sensor for SERS sensitive detection of phthalate plasticizers in biological tear and serum fluids.

Phthalate plasticizers (PAEs) illegally used in food pose a great threat to human health. A new and efficient sensing platform for the sensitive detection of the PAE residues in biological fluids needs to be designed and developed. Here, we report a simple and reliable surface-enhanced Raman spectroscopy (SERS) active platform with extralong hot spots of Au nanobipyramids@Ag nanorods (Au NBPs@Ag NRs) for the rapid and sensitive detection of PAEs in biological fluids. To achieve high activity, Au NBPs@Ag NRs with different shell lengths were fabricated by controlling the synthesis conditions, and the corresponding SERS properties were investigated by using crystal violet (CryV) and butyl benzyl phthalate (BBP). The experimental results showed that a longer shell length correlated to greater Raman activity, which was confirmed by finite-difference time-domain (FDTD) electromagnetic simulation. More importantly, the extralong hot spots of the Au NBPs@Ag NR SERS-active substrate showed excellent homogeneity and reproducibility for the CryV probe molecules (6.21%), and the detection limit was 10-9M for both BBP and diethylhexyl phthalate (DEHP). Furthermore, through the standard addition method, an extralong hot spots SERS substrate could achieve highly sensitive detection of BBP and DEHP in serum and tears fluids, and the detection limit was as low as 3.52 10-8M and 2.82 10-8M. Therefore, the Au NBPs@Ag NR substrate with an extraordinarily long surface is efficient and versatile, and can potentially be used for high-efficiency sensing analysis in complex biological fluids.

Development and Characterization of Polymeric-based Biomaterial from Agro-food Waste: A Sustainable and Eco-friendly Approach Towards Plastic Pollution

Commercial plastics are potentially hazardous and can be carcinogenic due to the incorporation of chemical additives along with other additional components utilized as brominated flame retardants and phthalate plasticizers during production that excessively produce large numbers of gases, litter, and toxic components resulting in environmental pollution. Biodegradable plastic derived from natural renewable resources is the novel, alternative, and innovative approach considered to be potentially safe as a substitute for traditional synthetic plastic as they decompose easily without causing any harm to the ecosystem and natural habitat. The utilization of undervalued compounds, such as by-products of fruits and vegetables in the production of biodegradable packaging films, is currently a matter of interest because of their accessibility, affordability, ample supply, nontoxicity, physiochemical and nutritional properties. Industrial food waste was processed under controlled conditions with appropriate plasticizers to extract polymeric materials. Biodegradability, solubility, and air test analysis were performed to examine the physical properties of polymers prior to the characterization of the biofilm by Fourier-transformed infrared spectroscopy (FTIR) for the determination of polymeric characteristics. The loss of mass examined in each bioplastic film was in the range of 0.01g to 0.20g. The dimension of each bioplastic was recorded in the range of 4.6 mm to 28.7 mm. The existence of -OH, C=C, C=O stretching, and other crucial functional groups that aid in the creation of a solid polymeric material are confirmed by FTIR analysis. This study provides an alternative approach for sustainable and commercially value-added production of polymeric-based biomaterials from agro-industrial waste as they are rich in starch, cellulose, and pectin for the development of bio-plastics. The rationale of this project is to achieve a straightforward, economical, and durable method for the production of bio-plastics through effective utilization of industrial and commercial fruit waste, ultimately aiding in revenue generation.

Toxicity assessment of di(2-ethylhexyl) phthalate using zebrafish embryos: Cardiotoxic potential

Plasticizers are considered as newly emerged contaminants. They are added to plastics to increase their flexibility and softness. Phthalate plasticizers including the Di-2-ethylhexyl phthalates (DEHP) are toxic and induce adverse effects on the different organization levels of the environment. In the current study, we investigated the potential toxicity of DEHP using Zebrafish as a biological model. Five ascending concentrations of DEHP were tested in embryos throughout 96 hpf: 0.0086, 0.086, 0.86, 8.6, and 86 mg/L. Embryotoxicity assessments revealed limited lethal effects on DEHP-exposed embryos, yet notable anticipation of the hatching process was observed at 48 hpf. Although DEHP showed negligible influence on the length and pericardial area of exposed embryos, it led to multiple bodily deformities. Gene expression analyses of key cardiogenic and inflammatory genes evidenced alterations in tbx20, bcl2, and il1b expression in Zebrafish embryos at 96 h post-fertilization. Results from the cardiac function analysis displayed that DEHP significantly affected the arterial pulse and linear velocity within the Posterior Cardinal Vein (PCV) of exposed fish. These findings strongly advance that even at low concentrations, DEHP can be considered as potential toxic agent, capable of inducing cardiotoxic effects.

An ultrasensitive photoelectrochemical biosensor based on AgBiS2/CdS photoanode and multiple signal amplification strategy for the detection of dibutyl phthalate plasticizer

Herein, a novel AgBiS2/CdS heterojunction was developed for the construction of sensitive biosensor for dibutyl phthalate (DBP) detection. Compared with the pristine CdS, the AgBiS2/CdS heterojunction exhibited enhanced photocurrent because of the promoted photo-carriers transfer due to the matched energy band arrangement between AgBiS2 and CdS. Based on this AgBiS2/CdS photoanode and a signal amplification strategy integrates DNAzyme-assisted walker reaction and hybridization chain reaction, a sensitive PEC sensing platform was designed for the detection of DBP. A wide detection ranges from 1 fM to 10 nM and a low detection limit of 0.3 fM were achieved. The proposed PEC biosensor with satisfactory sensitivity, selectivity, and stability shows potential application in environmental monitoring.

Environmental-friendly extraction of di(2-ethylhexyl) phthalate from poly(vinyl chloride) using liquefied dimethyl ether

Poly(vinyl chloride) (PVC) is one of the most widely used plastics. However, a major challenge in recycling PVC is that there is no economical method to separate and remove its toxic phthalate plasticizers. This research made a breakthrough by extracting PVC with liquefied dimethyl ether (DME) and successfully separating the plasticizer components. Nearly all (97.1 %) of the di(2-ethylhexyl) phthalate plasticizer was extracted within 30 min by passing liquefied DME (285 g) through PVC at 25 °C. The compatibility of PVC with organic solvents, including liquefied DME, was derived theoretically from their Hansen solubility parameters (HSP), and actual dissolution experiments were conducted to determine the optimal PVC solvents. A liquefied DME mixture was used to dissolve PVC, and the extract was diluted with ethanol to precipitate the dissolved PVC. We demonstrated that liquefied DME is a promising method for producing high quality recycled products and that the process retains the fundamental properties of plasticizers and PVC without inducing degradation or depolymerization. Because of its low boiling point, DME can be easily separated from the solute after extraction, allowing for efficient reuse of the solvent, extracted plasticizer, and PVC. DME does not require heat and produces little harmful wastewater, which significantly reduces the energy consumption of the plasticizer additive separation process.

The use of thermoplastic polyurethane composites to develop a model of the renal pelvicalyceal system by 3D printing

Composites based on thermoplastic polyurethanes (TPUR) were obtained using the twin-screw extrusion method. Influence of the addition of 6, 7 and 8 wt% silica and 1–3 wt%. aluminum oxide and 1–3 wt%. dibutyl phthalate (plasticizer) on Rockwell hardness, Charpy impact strength and tensile mechanical properties was tested. The best properties were obtained for a composite containing 8 wt% silica, 3 wt% aluminum oxide and 3 wt% dibutyl phthalates. For this composite, the renal pelvicalyceal system was obtained using the FFF method.