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BackgroundA growing literature has reported associations between traffic-related air pollution and breast cancer, however there are fewer investigations into specific ambient agents and any putative risk of breast cancer development, particularly studies occurring in populations residing in higher pollution areas such as Los Angeles.ObjectivesTo estimate breast cancer risks related to ambient air toxics exposure at residential addresses.MethodsWe examined the relationships between ambient air toxics and breast cancer risk in the Multiethnic Cohort among 48,665 California female participants followed for cancer from 2003 through 2013. We obtained exposure data on chemicals acting as endocrine disruptors or mammary gland carcinogens from the National-Scale Air Toxics Assessment. Cox proportional hazards models were used to estimate breast cancer risk per one interquartile range (IQR) increase in air toxics exposure lagged by 5-years. Stratified analyses were conducted by race, ethnicity, and hormone receptor types.ResultsAmong all women, increased risks of invasive breast cancer were observed with toxicants related to industries [1,1,2,2-tetrachloroethane (hazard ratio [HR] = 4.22, 95% confidence interval [95% CI] 3.18-5.60), ethylene dichloride (HR = 2.81, 95% CI 2.20-3.59), and vinyl chloride (HR = 2.27, 95% CI 1.81, 2.85); these 3 agents were correlated (r2 = 0.45-0.77)]. Agents related to gasoline production or combustion were related to increased breast cancer risk [benzene (HR = 1.32, 95% CI 1.24, 1.41), ethylbenzene (HR = 1.20, 95% CI 1.13-1.28), toluene (HR = 1.29, 95% CI 1.20-1.38), naphthalene (HR = 1.11, 95% CI 1.02-2.22), acrolein (HR = 2.26, 95% CI 1.92, 2.65)]. Higher hazard ratios were observed in African Americans and Whites compared to other racial and ethnic groups (p-heterogeneity

This work uses pure polyvinyl chloride (PVC) with magnesium oxide (MgO) nanoparticles to enhance PVC's optical and shielding properties. The distribution of MgO nanoparticles in the PVC polymer was shown using a scanning electronic microscope, x‐ray diffraction, and Fourier transform infrared. The prepared samples' optical parameters and thermal analysis are investigated using ultraviolet (UV) spectroscopy and thermogravimetric analysis, respectively. The shielding characteristics parameters for the prepared samples were experimentally tested using a Cs‐137 point source with an energy of 0.662 MeV, and the outcomes were contrasted with what the XCOM software had calculated. Results indicated that optical constants were significantly affected by the addition of MgO wt% concentration. The linear attenuation coefficient was directly proportional to the weight concentration of MgO nanoparticle filler in the PVC matrix, and the ability to absorb UV increased. Adding MgO nanoparticle concentrations improved the PVC composite's radiation shielding behavior. It concluded that the PVC/MgO nanoparticle‐prepared samples are suitable for packaging for industrial applications and apron shielding for medical applications. [ABSTRACT FROM AUTHOR]

Poly (vinyl chloride) (PVC) films modified with ethylenediamine (en) and doped by nanoparticles (TiO2, ZnO, NiO, and MgO). A mixture of 0.5 g PVC/en dissolved in THF and 0.01 wt % of nanoparticles were used in doping PVC to produce the nanocomposite films. All modified PVC films were characterized by different analysis techniques such as Fourier Transform Infrared (FTIR), Nuclear Magnetic Resonance Spectrometer (NMR), diffusive reflectance spectroscopy (DRS), X‐ray diffraction analysis (XRD), and scanning electron microscopy (SEM). The DRS was used to analyse the scattered IR energy of the samples at wavelengths between (250–1350 nm). The optical properties and oscillator strength were also studied, the transmittance and reflectance values declined for the PVC films, and the absorption coefficient was observed between (79–89 %). The direct energy gap decreased from 4.6 to 1.9, and the indirect energy gap reduced from 4.3 to 1.9. The XRD exhibited a semi‐crystalline structure and the SEM test exhibited a porous structure of all samples. The Urbach energy was increased from 0.8772 eV to 14.712 eV, single oscillator energy (Eo ${{E}_{o}}$) was also increased from 6.38 eV to 13.69 eV and the dispersion energy (Ed) ${{(E}_{d})}$ increased from 23.40 eV to 70.63 eV. Moreover, the surface roughness parameters Ra and Rq of the PVC films in modified and doping were increased from 3.86 nm to 8.14 nm, and 5.08 nm to 10.10 nm respectively. So, PVC results show increased optical properties after modification with en and doping by NPs are used in the light conversion and aerospace industries. [ABSTRACT FROM AUTHOR]

Polymers are omnipresent in our daily life thanks to their low production cost and their ease of implementation, which makes thermoplastics more usable in supplying drinking water, distributing cold and hot water, and transporting hot corrosive fluids and industrial chemicals, including inorganic acids. The material of our study is chlorinated polyvinyl chloride (CPVC); it has better thermal insulation and a wide operating temperature range. This paper deals with the impact of thermal aging over time on the behavior of CPVC by performing two types of tests according to ISO 15877 (EN ISO 15877) two types of tests; the first is thermal aging (Fig. 1) at a temperature of 95 °C and a pressure of 10 bars for periods of up to 2000 h and the second test exposure of the pipeline to pressure until bursting. On the basis of the test results, we can predict the rupture of the pipeline and thus avoid the dangerous accidents due to the bursting under the effect of the pressure and the high temperature; by using the results of this study, the inspectors change CPVC structures at the right time, neither too early when the part is still in good condition nor too late after failure; this will be very useful to save water and money and of course save the environment. [ABSTRACT FROM AUTHOR]

The strategic importance of developing environmentally friendly PVC biomass plasticizers with excellent anti-migration and plasticizing effects cannot be overstated. This paper delves into the synthesis and application of bio-based isosorbide di-epoxidized oleate (IDEO) as a secondary biomass plasticizer in polyvinyl chloride (PVC) films. Explored were the synergistic effects between IDEO and dioctyl phthalate (DOP), alongside an assessment of the influence of the compound plasticizer on the properties of PVC products. The partial substitution of DOP resulted in PVC films with improved thermal stability, flexibility, and migration resistance. IDEO-10/PVC, in particular, exhibited a 64% increase in tensile strength compared to DOP/PVC and maintained thermal stabilization for over 280 min at 180 °C. With a glass transition temperature (Tg) of 33 °C, a plasticizing efficiency of 148%, and excellent cold resistance properties, IDEO-10/PVC outperformed DOP/PVC. IDEO-10/PVC migration resistance was significantly lower than in the original PVC resin with only DOP plasticizers under three different polar conditions. Transmittance remained above 87% after 10 days of UV irradiation. Molecular dynamics simulation further confirmed the synergistic plasticizing effect between IDEO and DOP at an IDEO addition of 10 phr. The environmentally friendly approach holds significant promise for the scaled-up application of PVC. [ABSTRACT FROM AUTHOR]

ABSTRACT A new palladium‐based catalyst system modified with dibenzofuran (DBF) was developed for acetylene hydrochlorination. The optimal Pd‐DBF/SAC catalyst with the 0.5 wt% Pd loading and the 15 wt% DBF loading exhibits an elevated performance of 99.9% acetylene conversion and 99.9% vinyl chloride selectivity for more than 400 h. Characterization analysis and density functional theory (DFT) simulations revealed that the presence of oxygen‐containing DBF species of the Pd‐DBF/SAC catalyst prevents the reduction and loss of Pd species, inhibits the carbon deposition and enhances the HCl adsorbability, resulting in superior catalytic activity and stability for acetylene hydrochlorination. [ABSTRACT FROM AUTHOR]

Occupational dermatitis (OD) is an inflammatory skin disease stemming from exposure to specific substances within a work setting. As the second most prevalent occupational health concern in 2020, affecting 1.8 per 10,000 workers, OD poses a significant challenge to workforce well‐being and imposes a substantial economic burden through lost wages, decreased productivity, and increased healthcare spending. Dermatologists emerge as pivotal figures in recognizing risk factors and delivering essential care to individuals with OD. This review focuses on chemical hazards and toxic substances regulated by the Occupational Safety and Health Administration across general industry, maritime, and construction sectors. It explores the background of each hazard, pathophysiology to dermatitis, and human cases reported between 2017 and 2023 for formaldehyde, chromium, vinyl chloride, and cadmium. [ABSTRACT FROM AUTHOR]

Direct-on-Filter (DoF) analysis of respirable crystalline silica (RCS) by Fourier Transform Infrared (FTIR) spectroscopy is a useful tool for assessing exposure risks. With the RCS exposure limits becoming lower, it is important to characterize and reduce measurement uncertainties. This study systematically evaluated two filter types (i.e., polyvinyl chloride [PVC] and polytetrafluoroethylene [PTFE]) for RCS measurements by DoF FTIR spectroscopy, including the filter-to-filter and day-to-day variability of blank filter FTIR reference spectra, particle deposition patterns, filtration efficiencies, and pressure drops. For PVC filters sampled at a flow rate of 2.5 L/min for 8 h, the RCS limit of detection (LOD) was 7.4 μg/m3 when a designated laboratory reference filter was used to correct the absorption by the filter media. When the spectrum of the pre-sample filter (blank filter before dust sampling) was used for correction, the LOD could be up to 5.9 μg/m3. The PVC absorption increased linearly with reference filter mass, providing a means to correct the absorption differences between the pre-sample and reference filters. For PTFE, the LODs were 12 and 1.2 μg/m3 when a designated laboratory blank or the pre-sample filter spectrum was used for blank correction, respectively, indicating that using the pre-sample blank spectrum will reduce RCS quantification uncertainty. Both filter types exhibited a consistent radially symmetric deposition pattern when particles were collected using 3-piece cassettes, indicating that RCS can be quantified from a single measurement at the filter center. The most penetrating aerodynamic diameters were around 0.1 µm with filtration efficiencies ≥ 98.8% across the measured particle size range with low-pressure drops (0.2–0.3 kPa) at a flow rate of 2.5 L/min. This study concludes that either the PVC or the PTFE filters are suitable for RCS analysis by DoF FTIR, but proper methods are needed to account for the variability of blank absorption among different filters. [ABSTRACT FROM AUTHOR]

The EFSA Panel on Food Contact Materials (FCM) assessed the safety of the substances 'wax, rice bran, oxidised' and 'wax, rice bran, oxidised, calcium salt', used as additives up to 0.3% in polyethylene terephthalate (PET), polyamide (PA), thermoplastic polyurethane (TPU), polylactic acid (PLA) and poly(vinyl chloride) (PVC) in contact with all food types for long‐term storage at room temperature and below, after hot‐fill and/or heating. The substances consist of the chemical classes wax esters, carboxylic acids, alcohols and calcium salts of acids, along with an unidentified organic fraction up to ■■■■■ w/w. Migration into 10% ethanol and 4% acetic acid was below 0.012 mg/kg for each chemical class, and about 0.001 mg/kg for the unidentified fraction. In isooctane, migration was up to 0.297 mg/kg food for wax esters, below 0.01 mg/kg food for the other chemical classes and about 0.02 mg/kg food for the unidentified fraction. The contact with dry food and food simulated by 20% ethanol were considered covered by the migration tests with aqueous simulants. Based on genotoxicity assays and compositional analyses, the constituents of the chemical classes did not raise a concern for genotoxicity. The potential migration of individual constituents or groups of chemically‐related compounds of the unidentified fraction would result in exposures below (for aqueous food) and above (for fatty food) the threshold of toxicological concern for genotoxic carcinogens. Therefore, the FCM Panel concluded that the substances are not of safety concern for the consumer, if used as additives up to 0.3% w/w in PET, PLA and rigid PVC materials and articles intended for contact with all food types except for fatty foods, for long‐term storage at room temperature and below, including hot‐fill and/or heating up to 100°C for up to 2 h. [ABSTRACT FROM AUTHOR]

The paper presents the results of testing the properties of wood–polymer composites (WPC) based on plasticised poly(vinyl chloride) (PVC-P). Materials with variable contents of wood filler (Arbocel C 320) or plasticiser (di-isononyl phthalate) were produced and then analysed. The share of wood flour in the material was up to 50 phr, and the plasticiser content was up to 40 phr. Functional properties, such as tensile properties, mechanical properties at variable temperature (DMTA), and water absorption, as well as processing properties such as rheological properties and analysis of the fusion process, were analysed. The influences of wood flour and plasticiser on the composites' properties in the solid and melted state were found. For example, with 40 phr of plasticiser, increasing the filler share from 0 phr to 50 phr resulted in an increased tensile modulus from 18 MPa to 274 MPa and viscosity at a share rate of 20 s−1, from 721 Pa·s to 1581 Pa·s. However, increasing the share of plasticiser from 20 phr to 40 phr with 30 phr of filler reduces the value of these properties from 1760 MPa to 112 MPa and from 2768 Pa·s to 1151 Pa·s, respectively. It was also found that increasing the share of wood flour in the composite noticeably reduces the effectiveness of the plasticiser. [ABSTRACT FROM AUTHOR]

Hollongdione is the first recorded example of the occurrence of a dammarane hexanor-triterpene in nature possessing antiviral and cytotoxic activity. Its simple one-stage transformation into compounds with terminal alkyne and vinyl chloride fragments via the interaction with phosphorus halides is reported. The copper(I)-catalyzed Mannich reaction of 3-oxo-22,23,24,25,26,27-hexanor-dammar-20(21)-in 3 led to a series of aminomethylated products, while 17-carboxylic acid was obtained by ozone oxidation of 3-oxo-22,23,24,25,26,27-hexanor-dammar-20-chloro-20(21)-en 4; the following direct amidation of the latter has been developed. The structures of all new molecules were established by spectroscopic studies that included 2D NMR correlation methods; the molecular structures of compounds 2–5 were determined by X-ray analysis. [ABSTRACT FROM AUTHOR]

Poly(vinyl chloride) (PVC) films were synthesized by incorporating organic groups, specifically amino groups derived from ethylene di-amine (en). The casting process was employed, with tetrahydrofuran (THF) utilized as the solvent. The incorporation of 4 metal oxide nanoparticles (NPs), namely MgO, ZnO, NiO and TiO2, was carried out to enhance the stability of the films during light exposure. The effect of UV radiation dose was significant. Subsequent exposure of the PVC films to ultraviolet light enabled the evaluation of resulting damage through various analytical and morphological techniques. The utilization of infrared spectroscopy and weight loss study suggested that the films incorporating additives exhibited less harm and little alterations on the surface, as compared to the unaltered film. Among the modified films, the PVC-en/TiO2 NPs film exhibited the highest resistance against the photodegradation process, as evidenced by the data derived from FTIR spectra, weight loss measurements, and surface morphology analyses. Titanium dioxide nanoparticles have been good PVC photostabilizer because of its capacity to block ultraviolet (UV) radiation. The atomic force microscopy (AFM) photographs of the PVC-en/TiO2 NPs film after irradiation revealed a smooth surface, exhibiting a roughness factor (Rq) of 34.3, in contrast to the PVC (blank) which had a roughness factor of 282.2. SEM images for irradiated PVC films reveal the existence of cracks, cavities, protrusions, blemishes and formless, uneven surfaces. Microscopic images revealed that the surface of untreated PVC films exhibited significantly more pronounced damage and anomalies following irradiation compared to modified PVC films incorporating nano-metal oxides. [ABSTRACT FROM AUTHOR]

Ru single-atom catalysts have great potential to replace toxic mercuric chloride in acetylene hydrochlorination. However, long-term catalytic stability remains a grand challenge due to the aggregation of Ru atoms caused by over-chlorination. Herein, we synthesize an asymmetric Ru-In atomic pair with vinyl chloride monomer yield (>99.5%) and stability (>600 h) at a gas hourly space velocity of 180 h−1, far surpassing those of the Ru single-atom counterparts. A combination of experimental and theoretical techniques reveals that there is a strong d-p orbital interaction between Ru and In atoms, which not only enables the selective adsorption of acetylene and hydrogen chloride at different atomic sites but also optimizes the electron configuration of Ru. As a result, the intrinsic energy barrier for vinyl chloride generation is lowered, and the thermodynamics of the chlorination process at the Ru site is switched from exothermal to endothermal due to the change of orbital couplings. This work provides a strategy to prevent the deactivation and depletion of active Ru centers during acetylene hydrochlorination. Stable operation of acetylene hydrochlorination remains a challenge due to over-chlorination of Ru. Here, the authors propose a Ru-In atom pair with d-p orbital coupling that switches the thermodynamics of chlorination process and improves stability. [ABSTRACT FROM AUTHOR]

Hollow-fiber membranes for nanofiltration were prepared from the blending of Poly (ethylene glycol) (PEG) with Poly (vinyl chloride) (PVC) with different PEG molecular weights (400 and 4000 g/mol) and PVC via a dry/wet spinning process. In the spinning process, the effects of air gap, wind-up speed, dope extrusion rate, and bore extrusion rate were examined. In addition, the different lengths of the center tube, which acted as the inner-side fiber diameter during the preparation of hollow-fiber membranes, were studied. This research was investigated in order to observe the morphological, dielectric, and dynamic mechanical thermal properties to identify a suitable preparation of a hollow-fiber membrane for feasible applications. The morphology of the PVC-580 blended PEG-400 5 weight percent hollow-fiber membrane was seen to have a dense skin on both the inner and outer fiber surface, along with a suitable dope viscosity. Moreover, it offered finger-like substructures that could provide a high applicable feed-stream permeability and selectivity. Finger-like substructures were present on the near inner fiber surface at the controlled center-tube length of 0.3 cm, more so than at the center tube of 1 cm. This was because the solvent and non-solvent in the lumen tube exchanged more quickly than they did in the coagulant bath. The effect of the wind-up speed during the spinning process was significantly influenced by an affordable hollow fiber that can be indicated by the drawing ratio (λ). It was found that the drawing ratio of 3.3 showed a thickness thinner than 2.6 and 2.0, respectively. In summary, a controlled wind-up speed, an acceptable dope viscosity, and—most importantly—an agglomerated time resulted in membrane preparation. [ABSTRACT FROM AUTHOR]

Using the abundant and cost‐effective oleic acid and isosorbide with excellent properties as raw materials, the plasticizers of isosorbide di‐oleate (IDO) and isosorbide di‐epoxidized oleate (IDEO) with good plasticizing effect, low cost and green safety were synthesized by esterification and epoxidation reaction. The molecular structure of the synthesized plasticizers was characterized by FT‐IR and 1H NMR. The PVC shows better flexibility when IDEO or IDO plasticizer is used than commercial DOP. In particular, IDEO‐40 has 34% higher tensile strength and 17% higher elongation at break than DOP‐40. The introduction of epoxy groups on the carbon–carbon double bond of fatty acids meets the high thermal stability of plasticized film. The residual amount of IDEO‐40 is 7.01%, and at a high temperature of 180 °C, it can maintain high heat resistance for more than 220 min and transmittance of over 86%. Moreover, IDEO demonstrates excellent resistance to migration and volatilization. However, PVC films plasticized with IDO display reduced mechanical properties, cold resistance, and resistance to volatilization and migration due to the presence of non‐rotating carbon–carbon double bonds. The results indicate that these bio‐based plasticizers hold promise for practical applications in PVC products, offering improved environmental sustainability and performance characteristics. [ABSTRACT FROM AUTHOR]

Poly(vinyl chloride) (PVC) and activated carbon (AC) powders were hot-pressed into (PVC)100–x/(AC)x thin-film composites (TFCs), where x = 0.2–30 wt%. The nanostructure, morphology, and composition of AC were investigated by TEM, SEM, and EDX. The thermal stability and surface carbon-oxygen groups of the AC filler were determined by thermolysis in air and vacuum. The AC effect on the (PVC)100–x/(AC)x TFCs transparency to the electromagnetic radiation (EMR) was demonstrated at Ka-band microwave frequencies. Characteristically, the EMR reflection of the TFCs increases with the x value. For reduced EMR reflection, these TFCs should contain only 0.2 wt% AC. [ABSTRACT FROM AUTHOR]

Background: Drinking water at U.S. Marine Corps Base (MCB) Camp Lejeune, North Carolina was contaminated with trichloroethylene and other industrial solvents from 1953 to 1985. Methods: A cohort mortality study was conducted of Marines/Navy personnel who, between 1975 and 1985, began service and were stationed at Camp Lejeune (N = 159,128) or MCB Camp Pendleton, California (N = 168,406), and civilian workers employed at Camp Lejeune (N = 7,332) or Camp Pendleton (N = 6,677) between October 1972 and December 1985. Camp Pendleton's drinking water was not contaminated with industrial solvents. Mortality follow-up was between 1979 and 2018. Proportional hazards regression was used to calculate adjusted hazard ratios (aHRs) comparing mortality rates between Camp Lejeune and Camp Pendleton cohorts. The ratio of upper and lower 95% confidence interval (CI) limits, or CIR, was used to evaluate the precision of aHRs. The study focused on underlying causes of death with aHRs ≥ 1.20 and CIRs ≤ 3. Results: Deaths among Camp Lejeune and Camp Pendleton Marines/Navy personnel totaled 19,250 and 21,134, respectively. Deaths among Camp Lejeune and Camp Pendleton civilian workers totaled 3,055 and 3,280, respectively. Compared to Camp Pendleton Marines/Navy personnel, Camp Lejeune had aHRs ≥ 1.20 with CIRs ≤ 3 for cancers of the kidney (aHR = 1.21, 95% CI: 0.95, 1.54), esophagus (aHR = 1.24, 95% CI: 1.00, 1.54) and female breast (aHR = 1.20, 95% CI: 0.73, 1.98). Causes of death with aHRs ≥ 1.20 and CIR > 3, included Parkinson disease, myelodysplastic syndrome and cancers of the testes, cervix and ovary. Compared to Camp Pendleton civilian workers, Camp Lejeune had aHRs ≥ 1.20 with CIRs ≤ 3 for chronic kidney disease (aHR = 1.88, 95% CI: 1.13, 3.11) and Parkinson disease (aHR = 1.21, 95% CI: 0.72, 2.04). Female breast cancer had an aHR of 1.19 (95% CI: 0.76, 1.88), and aHRs ≥ 1.20 with CIRs > 3 were observed for kidney and pharyngeal cancers, melanoma, Hodgkin lymphoma, and chronic myeloid leukemia. Quantitative bias analyses indicated that confounding due to smoking and alcohol consumption would not appreciably impact the findings. Conclusion: Marines/Navy personnel and civilian workers likely exposed to contaminated drinking water at Camp Lejeune had increased hazard ratios for several causes of death compared to Camp Pendleton. [ABSTRACT FROM AUTHOR]

To replace traditional phthalate plasticizers, our previous research revealed that trioctyl citrate (CA) with an alkyl chain containing 8 carbon atoms (C8) exhibited excellent plasticizing properties. In order to delve deeper into the plasticization effects of CA isomers, CA with different side‐chain structures (C8‐Line, C8‐Branch, and C8‐Star) were synthesized by esterification reactions, and various CA/polyvinyl chloride (PVC) composite films with different CA contents were prepared using a solution casting method. The plasticization mechanisms of these isomers were systematically explored through experimental and molecular dynamics simulations. The results indicate that C8‐Branch demonstrates the optimal plasticizing effect, followed by C8‐Line, while C8‐Star exhibits poorer performance. The C8‐Branch/PVC composite system displays the best plasticizing effect, attributed to the strong interaction forces between the Cl atoms of PVC and the COO groups of CA. On the contrary, the formation of stable dipole pairs between C8‐Star and PVC is impeded by steric hindrance effects. The interaction between the two is predominantly dependent on the intertwining of the alkyl chains in C8‐Star with the PVC chains, also elucidating the observed higher migration rate in the C8‐Star/PVC system. This study provides technical guidance and theoretical basis for the optimized design of high‐performance CA/PVC composites. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel solvent extraction technique was developed for PVC plasticizers. • Subcritical fluid dimethyl ether (DME) effectively eliminated all plasticizer. • Compatibility was evaluated using hansen solubility parameters. • DME extraction does not cause DEHP plasticizer or PVC degradation. 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. [ABSTRACT FROM AUTHOR]

The limited available data on human internal exposure poses a significant challenge in assessing the risks associated with micro and nanoplastics (MNPs) to human health. A contributing factor to this challenge is the scarcity of sensitive analytical methods to quantify the mass concentration of plastic polymers in human blood. In this study we present an improved and validated method for quantitatively analysing polyethylene (PE), polyethylene terephthalate (PET), poly(vinyl chloride) (PVC), poly(methyl methacrylate) (PMMA), polypropylene, and polystyrene in human whole blood samples. We introduce and apply stringent quality assurance and quality control procedures, including the validation of the method using quality control samples and continuous monitoring of batch analyses to ensure data reliability. Expanding upon prior pioneering work by Leslie et al. (2022), we optimised the pyrolysis-gas chromatography–mass spectrometry (Py-GC-MS) conditions to enhance method sensitivity and selectivity. Recovery experiments demonstrated a high level of accuracy and precision, with values ranging from 68 to 109% for quality control samples. Applying this method to whole blood samples (n = 68), we identified plastic polymers in 64 samples, with PE as the predominant polymer, followed by PVC, PET, and PMMA. In 17 blood samples, polymer concentrations were found to exceed the limit of quantitation, with a mean of 1070 ng/mL for the summed polymer concentrations, ranging between 170 and 2490 ng/mL. The mean of the sum of polymers across all blood samples (n = 68) was 268 ng/mL. These findings underscore the pressing need for further research aimed at comprehensive MNP quantification in human matrices, considering the potential health implications. [ABSTRACT FROM AUTHOR]

Kinetics of non‐oxidative thermal degradation of poly(vinyl chloride) (PVC) plasticized with di(2‐ethylhexyl)phthalate and epoxidized linseed oil (ELO) were studied using differential scanning calorimetry. PVC thermal degradation autocatalyzed by forming HCl is delayed in the presence of acid scavenging ELO. Direct HCl elimination rates during steady state degradation (induction period) were almost independent on ELO concentration, with rate constants ranging from ≈3.2×10−6 s−1 at 463 K to ≈7.0×10−5 s−1 at 503 K. Activation energy of HCl elimination increased with glass transition temperature (Tg) increase from 136.0 kJ mol−1 at Tg=260.3 K to 141.9 kJ mol−1at Tg=274.2 K. Diffusion coefficients of HCl diffusion in plasticized PVC deduced using Williams‐Landel‐Ferry equation were of the order of 10−4 cm2 sec−1. Calculated activation energy of HCl diffusion in plasticized PVC was ≈30 kJ mol−1. The rate constants of PVC autocatalytic degradation were derived from the experimental data (for the 1st time) using Šesták‐Berggren approach and ranged from 3.2×10−2 sec−1 at 503 K to 4.4×10−3 sec−1 at 463 K. Autocatalysis activation energies ranged from 70.4 kJ mol−1 to 85.1 kJ mol−1 and increased with increase of glass transition temperature. It was established that PVC degradation kinetics was not controlled by HCl diffusion. Compensation effect was observed for initial and catalyzed PVC degradation. [ABSTRACT FROM AUTHOR]

In this article, a new class of biocompatible shape‐memory polymers (SMPs) through blending pcolyvinyl chloride or vinyl (PVC) and poly(ε‐caprolactone) (PCL) is introduced. The compressive shape‐memory behaviors of 4D‐printed SMP PVC with 5 and 10 wt% of PCL are studied in detail. In this respect, a set of experiments are carried out to understand thermomechanical responses of PVC–PCL blends under various shape‐memory parameters like programming temperature, load‐holding time, applied strain, and recovery temperature. Dynamic mechanical thermal analysis and scanning electron microscope imaging are also performed to provide thermal and morphological analyses. It is found that by raising the recovery temperature from 45 to 65 °C, the shape recovery ratio increases from 5.63 to 7.92 MPa when the PVC–PCL10 is programmed via the hot‐programming (HP) protocol. The highest level of shape fixity (100%) and the best performance of stress relaxation are achieved for HP sample, while the highest shape recovery ratio (100%) is obtained for cold programming. By applying the load‐holding time, the amount of shape fixity can reach from 88.14% to 100%. Results of this research are expected to provide an insightful understanding of the shape‐memory behaviors of PVC–PCL and be instrumental for 4D printing and programming of shape‐adaptive structures like shape‐memory intervertebral cages as spinal support devices. [ABSTRACT FROM AUTHOR]

This paper offers a thorough unfolding of the many contributions that water‐soluble polymers (WSPs) play in cementitious composites. The several forms of WSPs—natural, semi‐synthetic, and artificial—are examined, and their methods of action in cementitious composites are investigated. The topics of binding, association, adhesion, complexation, and bridge creation are covered in the literature. The effects of WSPs on the microstructure, freshness, mechanical properties, and durability of cement‐based goods are also investigated in this review. The advantages and disadvantages of utilizing WSPs in cement‐based products are also discussed. Following a detailed analysis of the most significant findings, recommendations are made for both academic and practical research areas and applications. This study provides useful information for both experts and novices by elucidating the multi‐applications of WSPs in cementitious materials. [ABSTRACT FROM AUTHOR]

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This article is the first edition of the Process Safety Division News (PSN), which has been renamed due to the Safety and Health Division being renamed the Process Safety Division (PSD). The newsletter is missing some topics due to a change in editors, but the Fall edition will be more complete. The article also highlights the successful 2024 Annual Meeting and Evening Reception at the 20th Global Congress on Process Safety (GCPS), where the Process Safety Division made its official debut after a name change in 2023. The article announces Lisa Long as the recipient of the 2024 Walton-Miller Award for her outstanding contributions to chemical engineering in the fields of loss prevention, safety, and health. Lisa Long has a long history of exceptional service to the American Institute of Chemical Engineers (AIChE) and continues to serve the organization. This document includes a tribute to Adrian Sepeda, a fellow of the CCPS who worked in the chemical industry for 33 years. Sepeda was known for his passion for process safety and his contributions to the field. The document also provides updates from OSHA and the EPA regarding the RMP rule and the Compliance Directive on Process Safety Management of Highly Hazardous Chemicals. The updates can be found on the respective agencies' websites. [Extracted from the article]

A trade‐off dilemma exists for simultaneously improving the mechanical properties and flame resistance of flexible polyvinyl chloride (fPVC)/magnesium hydroxide (MH) composites. In this study, epoxy phosphate ester (EPE), a hydrophobic surface modifier of MH, was synthesized using a self‐emulsification method. After modification, EPE was bonded to the surface of MH (MHEPE) without altering its morphology. The results of limiting oxygen index and cone calorimetry tests indicated that fPVC/MHEPE exhibited better flame retardancy and smoke suppression effects than did fPVC/MH. The peak of the heat release rate, total heat release, peak of the smoke production rate, and total smoke production of the fPVC/MHEPE composite were 206.0 kJ m−2, 45.90 MJ m−2, 0.0729 m2 s−1, and 9.88 m2, which were 8.64%, 14.00%, 27.61%, and 9.02% lower than those of the fPVC/MH composite, respectively. For the fPVC/MHEPE composite, a compact and continuous char residue formed, which could inhibit heat and flammable volatile migration between the matrix and burning zones. In the gas phase, the dilution effect of H2O vapor reduced the concentrations of O2 and flammable volatiles. The free‐radical quenching effect of ·PO and ·PO2 also played a vital role in extinguishing flame and terminating combustion. Further, the introduction of EPE improved the tensile and impact strengths of the fPVC/MH composites because of the excellent interfacial compatibility between MHEPE and the fPVC matrix. This study provides a simple and workable solution for the trade‐off dilemma, and the remarkable flame retardancy and mechanical properties of the fPVC/MHEPE composite render it a promising cable material. [ABSTRACT FROM AUTHOR]

Microplastics are an emerging class of recalcitrant organic pollutants that are of general scientific and public interest nowadays. It would be ideal to remove microplastics from the environment through biodegradation, as biodegradation is a highly ecological and economically acceptable approach. Unfortunately, the efficiency of biodegradation of conventional plastic polymers is low. The application of a suitable pretreatment could increase the efficiency of biodegradation. In this study, the applicability of UV-C/H2O2 and UV-C/S2O82− advanced oxidation processes as pretreatments for the biodegradation of polystyrene and poly(vinyl chloride) microplastics by the yeast Candida parapsilosis was investigated. For the investigated range (pH 4–10, peroxide concentration up to 20 mM and treatment duration up to 90 min), the UV-C/H2O2 process proved to be more effective in degrading polystyrene microplastics, while the UV-C/S2O82− process was more efficient at degrading poly(vinyl chloride) microplastics. Samples pretreated under optimal conditions (90 min treatment time at a pH of 5.7 and H2O2 concentration of 20.0 mM for polystyrene samples; 90 min treatment time at a pH of 8.6 and S2O82− concentration of 11.1 mM for poly(vinyl chloride) samples) were subjected to biodegradation by Candida parapsilosis. The biodegradation conditions included an agitation speed of 156 rpm and an initial pH of 5.7 for the experiments with the polystyrene samples, while an agitation speed of 136 rpm and an initial pH of 4.9 were used for the poly(vinyl chloride) experiments. The initial value of the optical density of the yeast suspension was 1.0 in both cases. The experiments showed a positive effect of the pretreatment on the number of yeast cells on the surface of the microplastics. [ABSTRACT FROM AUTHOR]

Polyvinyl chloride (PVC)/polyethylene oxide (PEO)/x wt % polyaniline (PANI) polymer blends were produced using a solvent casting method. X-ray diffraction was used to investigate the formed blends. The effect of adding different amounts of PANI on the light absorbance, transmittance, reflectance, extinction coefficient, refractive index, optical dielectric properties, nonlinear optical parameters and relaxation time characteristics of the PVC/PEO blends were explored. The direct and indirect optical band gap energies of the undoped PVC/PEO were 4.25 and (4.06, 2.76) eV, respectively. The direct and indirect optical band gap energies were reduced to their lowest values (4.02, 3.1) and (3.68, 2.14, 1.12) eV as the amounts of PANI were increased to 0.2 wt %. The effect of alloying between PVC and PEO and adding PANI on the emitted fluorescence spectra under various excitation wavelengths were investigated. All samples displayed varying degrees of blue-violet, blue, or blue-green colors depending on the concentrations of PANI. [ABSTRACT FROM AUTHOR]

Chlorinated plastics are part of the everyday lives of consumers and producers alike. They can be found in buildings, automobiles, fashion, packaging and many other places. This prevalence makes them a considerable part of the plastic waste crisis. Interest in 'upcycling' (as opposed to recycling) has grown recently to augment the possibilities of managing plastic waste. The advances made in plastic upcycling have focused on polyethylene, polypropylene, poly(ethylene terephthalate) and polystyrene while chlorinated plastics, chiefly poly(vinyl chloride), have received much less attention. The release of chlorine‐containing molecules during treatment of chlorinated plastic greatly complicates cross‐method upcycling, or even the treatment of plastic mixes containing chlorinated plastics. This review presents a case for extracting value from chlorinated plastics by highlighting appealing upcycling products made owing to, or despite, the CCl bond via depolymerization, carbonization and modification. © 2024 Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]

Surface defects known as "gas checks" often mar the surfaces of poly(vinyl chloride) (PVC) calendered films. These defects are typically prevented through changes in the calender operating parameters, a costly exercise which also limits the sheet thickness and the production rate. Adding a low concentration of poly(caprolactone) (PCL)‐based star‐shaped compound can eliminate gas check defects in PVC calendering. The effects of a triheptylsuccinate‐terminated PCL with a PCL triol core and number average molecular weight of 540 g/mol (i.e., PCL540‐[(succ)‐C7]3) has been investigated on the material, thermal, and processing properties of PVC blends containing diisononyl phthalate (DINP) as a primary plasticizer and PCL540‐[(succ)‐C7]3 in low quantities (i.e., 0, 5, or 10 parts per hundred rubber (phr)) as a secondary plasticizer and processing aid. The most significant differences between PVC blends containing PCL540‐[(succ)‐C7]3 and those without are in the rheological properties of the PVC blends at higher temperatures and lower angular frequencies. Under these conditions, PVC blends containing 10 phr of PCL540‐[(succ)‐C7]3 have a complex viscosity nearly three times higher than those containing only DINP. PVC/PCL540‐[(succ)‐C7]3 blends had comparable tensile properties to those containing only DINP, with no significant change in maximum elongation and a small but significant increase of 28% in maximum stress. The addition of PCL540‐[(succ)‐C7]3 made it possible to produce calendered films without gas checks that were twice as thick as those produced in its absence. In addition to reduced wastage of marred films, the increased calender operating range for PVC films containing PCL540‐[(succ)‐C7]3 has the potential to significantly reduce energy costs for the calendering of thick PVC films. [ABSTRACT FROM AUTHOR]

The response of three of the most used commercial polymers (poly(vinyl chloride) (PVC), poly(ethylene terephthalate) (PET) and polypropylene (PP)) under irradiation with high repetition rate (1 kHz–1 MHz) femtosecond (450 fs) multi-pulse (N = 10–1500) laser at λ = 343 nm, 515 nm (1.40 J/cm2 for both former wavelengths) and 1030 nm (1.70 J/cm2) is reported, obtaining a study on how the absorption mechanism influences the processing efficiency for these materials. Tunable ablation depth and diameters are accomplished by modifying repetition rates at a constant fluence and number of pulses. The results highlight the role of absorption mechanism, repetition rate ranges and thermal properties of the materials for benefiting ablation efficiency. Furthermore, the use of high repetition rates improves the laser processing, reducing extended thermal effects and increasing ablation uniformity. [ABSTRACT FROM AUTHOR]

The present study evaluated the use of epoxidized esters of succinic acid, oleic acid, and propylene glycol as a bioplasticizer for poly(vinyl chloride) (PVC) and compared the results with the commercial phthalate plasticizer di(2‐ethylhexyl)phthalate. The chemical properties, structure, and biodegradation of the obtained bioplasticizer were analyzed. In order to analyze the influence of different PVC processing conditions on the properties of the obtained samples, the gelation process was carried out at 170, 180, 190, and 200°C at a time of 1.5–10.0 min. Mechanical properties, thermal characteristics, Fourier transform infrared spectroscopy analysis, plasticizer migration, and color change were determined for the resulting plasticized PVC samples. The performed studies allowed to confirm the obtaining of a biodegradable bioplasticizer (after 28 days, the decomposition rate in respirometry test was 72.7%). The optimal conditions for PVC processing were determined. For them the properties of the obtained material were superior. Processing PVC at 170°C for 7.5 min proved to be the most optimal conditions for the bioplasticizer synthesized in this study. Under these conditions, tensile strength of about 23 MPa and elongation at break of 200% were obtained, while plasticizer migration was very low (4.4% after 7 days and 6.8% after 28 days). [ABSTRACT FROM AUTHOR]

Poly(vinyl chloride) undergoes dechlorination in the presence of triethylsilane (Et3SiH) and a catalytic amount of [Cp2Zr(NPh2)][CH3B(C6F5)3] (1 b) at 40–80 °C, with up to 91 % efficiency. Stoichiometric reactivity studies conducted on cyclohexyl chloride as a model suggest that 1 b dechlorinates PVC by initial chloride abstraction, followed by hydride transfer to the cationic PVC chain from Et3SiH. Consumer items such as pipe fitting, vinyl disc or electric cable insulation undergo either dechlorination or hydrosilylation of the carbonyl‐containing copolymer (polyvinyl acetate) or plasticizer (phthalate). [ABSTRACT FROM AUTHOR]

The development of an electrochemical cobalt catalyzed C-Cl bond activation at room temperature for the nucleophilic addition of aryl and vinyl chlorides to α-ketoamides is described. The overall method operates through an electrochemically induced low valent cobalt catalyst that oxidatively adds to aryl or vinyl chlorides affording medicinally important 3-hydroxy oxindole and 3-hydroxypyrrolidinone scaffolds. The development of an enantioselective version using a chiral pyrox ligand is also demonstrated. [ABSTRACT FROM AUTHOR]

Homogeneous mercury-free catalysts synthesized using ionic liquids (ILs) have become increasingly popular due to their high activity and excellent stability for acetylene hydrochlorination. However, high viscosity as well as costliness limit the application of ILs. Here, for the first time, we explored the use of solvents for acetylene hydrochlorination since low-viscosity systems allow rapid mass and heat transfer processes. In the synthesized Ru–ILs–solvent system, tetraphenylphosphonium chloride (TPPC) shows excellent promoting effects on the reaction. Compared with the pure IL phase, the tetramethylene sulfone (TMS) system improves the catalytic performance, while the amount of IL used is reduced by more than 90%. Among the synthesized catalysts, Ru–TPPC–TMS shows the highest conversion rate of about 95% and vinyl chloride selectivity of more than 99.8% under the conditions of 170 °C and GHSV of 50 h−1. Briefly, this study provides new inspiration for the development of homogeneous catalysts for acetylene hydrochlorination. [ABSTRACT FROM AUTHOR]

Hydrogen chloride is produced as a by-product in industrial processes on a million-ton scale. Since HCl is inherently dangerous, its storage and transport are avoided by, e.g., on-site electrolysis providing H2 and Cl2 which usually requires complex cell designs and PFAS-based membranes. Here we report a complementary approach to safely store 0.61 kilogram HCl per kilogram storage material [NEt3Me]Cl forming the bichloride [NEt3Me][Cl(HCl)n]. Although HCl release is possible from this ionic liquid by heat or vacuum, the bichloride can be used directly to produce base chemicals like vinyl chloride. Alternatively, [NEt3Me][Cl(HCl)n] is electrolyzed under anhydrous conditions using a membrane-free cell to generate H2 and the corresponding chlorination agent [NEt3Me][Cl(Cl2)n], enabling the combination of these ionic liquids for the production of base chemicals. [ABSTRACT FROM AUTHOR]

Poly(vinyl chloride) (PVC) is the third most produced synthetic polymer in the world, irreplaceable in many applications including medical ones. The production of soft PVC presents a problem with volatile low-molecular plasticizers that can be harmful to human health. Therefore, they are often replaced with polymeric plasticizers, which are less effective and require higher processing temperature, however. In this work, we have studied a specific method of PVC plasticization consisting in the mixing of PVC with monomeric ε-caprolactone in a closed system. During thermal treatment of the mixture, in situ polymerization of the ε-caprolactone occurs, initiated by a tin stabilizer of PVC present in the mixture, which results in the formation of poly(ε-caprolactone), a non-toxic and bio-degradable polymeric plasticizer with various molar mass. In this way, a stable plasticized PVC material can be obtained, the thermal stability, softening range and mechanical properties of which correspond to the use of conventional plasticizers. [ABSTRACT FROM AUTHOR]

Urea cyanurate, as a new nitrogen-rich organic-based heat stabilizer, for the enhancement to thermal properties of polyvinyl chloride (PVC) is prepared via the simple precipitation method, in this study. Characterization, thermal and mechanical properties of the stabilized PVC were examined by means of fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA/DTG), X-ray photoelectron spectroscopy (XPS) measurements, discoloration test, congo red test and the weight-loss method, thermal aging test, and tensile analysis. Results showed that the thermal stability of PVC is improved after the addition of urea cyanurate in PVC formulation and weight loss related to HCl releasing in the normal PVC processing temperature (180°C) is less than 1%. Enhancement of the thermal properties and stability time of the PVC lead to decreased degradation tendency. Oven-aging test result showed that the color change during degradation process of PVC samples improved by adding the urea cyanurate. The tensile strength of stabilized samples were about 42%, higher as compared to the pure PVC. The optimum and best results for improving the thermal and mechanical properties of PVC were obtained by incorporating the 3 wt % of the urea cyanurate. [ABSTRACT FROM AUTHOR]

To date, there has been limited information in the literature on the application of carbon fibre-carbon nanotube systems for the modification of poly(vinyl chloride) (PVC) matrixes by micro- and nanometric fillers and an evaluation of the properties of the unique materials produced. This paper presents the results of newly designed unique multiscale composites. The advantages of the simultaneous use of carbon fibres (CFs) and carbon nanotubes (CNTs) in PVC modification are discussed. To increase the dispersibility of the nanofiller, CFs together with nanotubes were subjected to a sonication process. The resulting material was introduced into PVC blends, which were processed by extrusion. The ratio of components in the hybrid filler with CF_CNT was 20:1, and its proportion in the PVC matrix was 1, 5, and 10 wt.%, respectively. Comparatively, PVC composites modified only with carbon fibres were obtained. The structure, thermal, electrical, and mechanical properties and swelling resistance of the composites were studied. The study showed a favourable homogeneous dispersion of nanotubes in the PVC matrix. This enabled effective modification of the structure at the nanometric level and the formation of an interpenetrating network of well-dispersed hybrid filler, as evidenced by a decrease in volume resistivity and improvement in swelling resistance, as well as an increase in glass transition temperature in the case of PVC/CF_CNT composites. [ABSTRACT FROM AUTHOR]

Flexible intravenous solution containers (IV bags) were introduced to the marketplace in the early 1970s. These new containers were designed to replace glass IV bottles and were quickly adopted widely for delivering medical solutions to patients throughout the world. The 40 years during which commercially available IV solutions in glass bottles were used, the healthcare industry grew dramatically with better patient outcomes while also reducing operational costs. These early developments then led to the rapid expansion of new medical devices that have been further developed to improve healthcare and reduce overall costs of the products and devices. It is not an exaggeration to suggest that the medical device industry was founded on the development of the flexible poly (vinyl chloride) (PVC) plastic IV tubing and bag. After the IV bag product lines grew to serve many markets, a new unmet need was discovered for an aseptically produced premixed drug container. This article will review how a new film was developed and used to produce the required aseptically made IV premixed drug product. It was, after the Food and Drug Administration (FDA) gave "clearance to market", a ground-breaking product, never before thought possible for the highly FDA-regulated and controlled industry. [ABSTRACT FROM AUTHOR]

The article presents research on the thermal decomposition of individual ingredients and compositions that are physical mixtures of emulsion poly(vinyl chloride) (PVC), cadmium yellow, and stearic acid. The results of the tests were TG, DTA, and DTG graphs. From their course, the initial decomposition temperatures, maximum decomposition rate, and final temperatures were determined, and changes in the mass of samples and the values of thermal effects were calculated. The influence of pigment and stearic acid on the thermal decomposition of PVC was investigated. Cadmium yellow, modified in an alkaline medium and containing hydroxyl groups, was also used for the tests. It was found that the presence of both pigment and stearic acid had a retarding effect on the initiation of thermal decomposition of PVC. The addition of CdS modified in an alkaline environment had a more or less similar effect on the initial decomposition temperature of PVC. Depending on the composition of the polymer and the value of the final temperature, different values of thermal effects and the amount of products formed were indicated. [ABSTRACT FROM AUTHOR]

Background: Chemicals emitted from industrial facilities include known or suspected mammary carcinogens and endocrine disruptors, but epidemiologic studies are limited. We evaluated associations between air emissions of multiple carcinogenic chemicals and postmenopausal breast cancer risk in a large prospective U.S. cohort. Methods: We used the U.S. Environmental Protection Agency’s Toxics Release Inventory to estimate historical airborne emissions (1987–1995) of 19 known and probable carcinogens for participants enrolled (1995–1996) in the NIH-AARP Diet and Health Study. Among 170,402 women, 15,124 breast cancers were diagnosed through 2018. We constructed inverse distance- and wind-weighted average emissions metrics within 1, 2, 5, and 10 km of the enrollment address for each chemical. We estimated multivariable adjusted HRs and 95 % CIs for categories (quartiles, tertiles, medians) of each chemical in association with breast cancer overall and separately by type (invasive, ductal carcinoma in situ) and estrogen receptor (ER) status. Results: We observed an association between benzene emissions and breast cancer risk that was strongest at 1 km (HRQ4 vs. non-exposed = 2.06, 95 %CI: 1.34–3.17; p-trend = 0.001). The magnitude of the association weakened with increasing distance (2 km HRQ4 vs. non-exposed = 1.17, 95 %CI=0.92–1.49; p-trend = 0.19; 5 km HRQ4 vs. non-exposed = 1.05, 95 %CI=0.94–1.16; p-trend = 0.37; 10 km HRQ4 vs. non-exposed = 0.95, 95 %CI=0.89–1.02; p-trend = 0.19) and appeared to be most relevant for invasive rather than intraductal disease. Overall risk was also elevated for vinyl chloride at 5 km (HR≥median vs. non-exposed = 1.20, 95 %CI=1.01–1.43; p-trend = 0.04), but not 2 km or 10 km. We observed suggestive associations for asbestos, trichloroethylene, and styrene in different subgroup analyses, but risk patterns were not clear across distances. Associations with other chemicals were generally null, with limited evidence of heterogeneity by disease type or ER status. Conclusions: An increased risk of breast cancer associated with relatively high levels of industrial benzene emissions warrants additional study, particularly among participants with diverse sociodemographic characteristics that live in areas with higher density of industrial facilities.

Poly(butyl acrylate) grafted styrene and acrylonitrile copolymer (PBA‐g‐SAN, ASA) with core–shell structures were prepared by emulsion polymerization technology to improve the toughness of the poly(vinyl chloride) (PVC). The mechanical properties of the PVC/ASA blends were investigated. The notch impact strength of the PVC/ASA blend could reach 1200 J/m when the 13 phr ASA was added to the PVC. This was several times more than pure PVC resin. Scanning electron microscopy analysis results indicated that the improvement in impact strength of the PVC/ASA blend was attributed to shear yielding induced by ASA particles. Additionally, subtle changes in the ratio of monomers in the shell layer led to significant fluctuations in the mechanical properties of the composites. Dynamic mechanical analysis showed that the intermolecular interaction forces between ASA particles and PVC resins played a key role in improving the toughness of PVC/ASA blend. [ABSTRACT FROM AUTHOR]

Herein, low molecular weight poly(vinyl chloride‐co‐n‐butyl acrylate‐co‐vinyl acetate) (PCBV) ternary copolymers with varied copolymer composition was employed as a novel polymeric lubricant in rigid PVC. The lubrication effect of PCBVs on the melting process and mechanical properties of the final PVC products were fully investigated. The results indicated that PCBV can serve either as an internal or as an external lubricant depending on its composition. PCBV‐45.5 terpolymer (PBA% ~ 45.5%) exhibits outstanding balance both internal and external lubricating roles. SEM‐EDS results show that addition PCBV‐45.5 form a film on the surface of PVC grains as similar as that adding both internal and external lubricants. Fusion characteristics and DMTA demonstrate that PCBV‐45.5 prolongs the fusion time (26% extension, 1.5 phr) and reduces the glass transition temperature (4.0 °C, 1.5 phr). Finally, the mechanical properties of rigid PVC have been greatly improved by using 1.5 phr PCBV‐45.5. In detail, the tensile strength increased from 54 to 59 MPa and the elongation at break increased from 10% to 30%, respectively. Meanwhile, the impact strength of PVC/PCBV‐45.5 is 3.6 times that of the blend without addition. The excellent performance of PCBV exhibited great potential as a polymeric lubricant candidate in rigid PVC composites. [ABSTRACT FROM AUTHOR]

A catalyst system based on palladium 2‐methylnaphthyl complexes bearing ylide‐functionalized phosphines (YPhos) was found to enable the selective γ‐arylation of 1,3‐dioxinone derivatives with diversely functionalized aryl, heteroaryl, and vinyl chlorides. The products were further converted into 1,3‐diketones and heterocycles, highlighting their function as synthetic hubs. Experimental and computational studies revealed that bulky, electron‐rich YPhos ligands are uniquely effective because they enable the oxidative addition of aryl chlorides at room temperature while at the same time efficiently promoting the rate‐limiting reductive elimination step of the thermally sensitive enolates. [ABSTRACT FROM AUTHOR]

In this work, dioctyl 2,5‐thiophenedicarboxylate (DOT), a potentially bio‐based plasticizer, was synthesized and evaluated as an alternative to traditional petroleum‐based plasticizers. The chemical structure of DOT was confirmed by FTIR and 1H NMR. Besides, its plasticization effect on poly(vinyl chloride) (PVC) was investigated in detail, and dioctyl 2,5‐furandicarboxylate (DOF) as well as dioctyl isophthalate (DOIP) with similar chemical structures were used as references. The DMA results showed that the glass transition temperature (Tg) of PVC/DOT, PVC/DOF, and PVC/DOIP was 45.1°C, 33.6°C, and 51.3°C, respectively, indicating that the plasticizing efficiency of DOT was better than that of DOIP but lower than that of DOF. However, the tensile test results exhibited that the elongation at the break of PVC/DOT was higher than that of PVC/DOF, which was attributed to the easy phase separation between DOF and PVC. In addition, DOT displayed the best volatility resistance and exudation resistance among the three plasticizers, attributed to its highest molecular weight. Moreover, the migration loss of DOT in non‐polar solvents was much smaller than that of DOIP because of its stronger molecular polarity. In conclusion, DOT has good potential to replace traditional petroleum‐based plasticizers and be used as a primary plasticizer for PVC. [ABSTRACT FROM AUTHOR]