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The pervasive presence of nanoplastics (NPs) in the environment has gained increasing attention due to their accumulation in living organisms. These emerging contaminants inevitably interact with extracellular polymeric substances along respiratory or gastrointestinal tracts, and diverse organic coating on the surface of NPs, known as bio- or eco-corona, is formed. Although its impact on altering the NP properties and potential cell internalization has been extensively examined, studies on its role in NP partitioning in the cell membrane are elusive yet. In this work, molecular dynamics is used to investigate the formation of chitosan (CT) corona centered on a polyvinyl chloride (PVC) nanoparticle and the uptake of the resulting complex onto lipid membranes. Coarse-grained models compatible with the newly developed Martini 3.0 force field are implemented for the two polymers employing the atomistic properties as targets in the parameterization. The reliability of the coarse-grained polymer models is demonstrated by reproducing the structural properties of the PVC melt and of solvated CT strands, as well as by determining the conformation adopted by the latter at the NP surface. Results show that the spontaneous binding of CT chains of high and intermediate protonation degrees led to the formation of soft and hard corona that modulates the interaction of PVC core with model membranes. The structural changes of the corona adsorbed at the lipid–water interface enable a subsequent transfer of the NP to the center of the saturated lipid membranes and a complete or partial transition to a snorkel conformation depending on the hydrophilic/hydrophobic balance in the CT–PVC complex. Overall, the computational investigation of the coarse-grained model system provides implications for understanding how the eco-corona development influences the uptake and implicit toxicology of NPs. [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]

Purpose. High-fidelity mannequins are increasingly used to train the medical staff on many medical procedures. Lately, a new challenge regarding echogenic materials to build ultrasound-responding phantoms has emerged. The challenge is to find materials with a suitable combination of ultrasound velocity and consistency to the touch. Methods. Bibliographic research was performed to identify materials with promising stiffness, shape retention, and ultrasound velocity combinations. As-standardized-as-possible specimens were realized and tested using an A-mode ultrasound machine to evaluate the US velocity through them. Four differently doped silicones, five gelatin-based materials, five synthetic gelatins, and a 3D printable resin were included in the study. After being tested, the materials were monitored for 12 days to assess their durability and shape retention and tested again to evaluate the ultrasound velocity's stability. In the paper, the results of the characterization and follow-up of the materials are presented. Results. Outcomes show that gelatins are exceptional soft tissue-mimicking materials in terms of ultrasound velocity and consistency to the touch, but are poor in terms of overtime stability and therefore suitable for disposable short-term phantoms only. Doped silicones present lower ultrasound velocity compared to the reference value of 1540 m/s found in the literature, but excellent overtime stability, and shape retention properties. Values close to biological ones were also given by the Elastic 50A and by polyvinyl chloride plastisol. Conclusion. The paper gives a quantitative overview of the fidelity of both already-in-use and non-conventional materials, focusing on the ultrasound velocity value through them and their longevity in terms of macroscopically observed dehydration, shape retention, and bacterial onset. [ABSTRACT FROM AUTHOR]

[Display omitted] • Polyvinyl chloride inhibits carbon nanotube formation until its content is below 5% • Dechlorinating agents mitigate the impact of Cl on carbon nanotube formation. • Red mud, the optimal dechlorination agent, yields 30 wt% carbon with higher quality. • Volatiles undergo catalysis, forming aromatics or aliphatics during dechlorination. The presence of chlorine in polyvinyl chloride (PVC) presents a major challenge for realizing the high-value utilization of real waste plastics. The objective of this research was to develop a chlorine-resistant process for the preparation of carbon nanotubes (CNTs) from mixed plastics containing PVC. This study investigates the influence of PVC content and various dechlorinating agents (CaO, Na 2 CO 3 , red mud (RM), ZSM-5, Fe-Al 2 O 3 , Fe(OH) 3) on CNTs formation. The results showed that PVC content exceeding 5 % significantly inhibits CNTs formation. Employing dechlorinating agents in the pyrolysis process results in a substantial yield of CNTs from mixed plastics containing 10 % PVC. Among the dechlorinating agents, RM proves to be the most effective, leading to the highest carbon yield (at 30 wt%) and superior CNTs quality. Other dechlorinating agents, except for ZSM-5, yield comparable results, although there were some obvious variations of volatiles. Further investigation of the role of dechlorinating agents from the perspective of volatiles evolution was conducted via Py-GC/MS, and found that the dechlorination agent efficiently absorbs the HCl from mixed plastics pyrolysis, while also exhibiting catalytic and regulatory influence on volatile components. These findings offer valuable insights for the development of a chlorine-resistant process in the preparation of CNTs from mixed plastics that contain PVC. [ABSTRACT FROM AUTHOR]

Background: S-lon® (S) is a locally produced polyvinyl chloride-based solvent cement. It is a clear, slightly viscous liquid. Other constituents include 1-cyclohexanone, 3-butanone, and 1-acetone. It is used ubiquitously for building construction in Sri Lanka. Although the clinical effects of the compound have not yet been ascertained, the constituents have been implicated in neurotoxicity, respiratory tract, eye and skin irritation, and delayed liver and renal injury. Case description: A 42-year-old South Asian male presented following self-ingestion of S. His vital parameters were stable and initially managed symptomatically. A few hours later, he developed central nervous system depression and stridor requiring elective intubation. Examination of the upper airway revealed inflammation and edema. He was sedated and ventilated, and intravenous dexamethasone was administered. Attempts at removal of the nasogastric tube after extubation on day 3 failed. The patient had to be reintubated and sedated owing to extreme agitation not responding to routine doses of sedatives. The nasogastric tube had been amalgamated after reacting with S, forming a solid clump, later found after removal. The posterior pharynx and nasopharynx were packed and later removed before extubation. The patient made a full recovery and was transferred to the ward on day 5. Conclusion: Ingestion of a sufficient quantity of S could result in gut absorption with central nervous system depression, coma, and even death. No antidote is available for toxicity, and management is largely supportive. As witnessed in our patient, chemical laryngitis and upper airway inflammation may lead to upper airway obstruction. Chemical reactions with medical equipment may lead to unforeseen outcomes. [ABSTRACT FROM AUTHOR]

Since the development of industry, sound absorption and noise reduction have gradually become an urgent problem to be solved. Lightweight polymer film materials are very effective in response to sound waves, and sound waves can easily cause vibration of the film, which can convert sound energy into vibration and film friction to achieve sound absorption. The application conditions of the film material are very harsh, that is, a support body is required to fix the film and the film needs to be tensioned. The film is very thin and easy to damage. The idea of this research is to transform the film into a bubble structure and use a large number of film bubbles to form a cavity structure material. As a unit of the sound absorption structure, bubbles can avoid damage to the film. In this paper, commercial polyvinyl chloride film bubble materials are used to prepare two kinds of film multicavity structure materials, and the sound absorption performance of this film multicavity structure material is studied. The research results show that this film multicavity structure material has very excellent broadband sound absorption performance, which changes the narrow band sound absorption properties of the usual film single cavity. The average sound absorption coefficient can reach 0.84 in frequency range from 500 Hz to 6400 Hz. This structural material has a single peak sound absorption curve at the middle and low frequency bands, which is the characteristic of resonance sound absorption. And at the middle and high frequency bands, it exhibits the characteristics of broadband sound absorption. The film multicavity structure material has both cavity sound absorption and broadband sound absorption characteristics. [ABSTRACT FROM AUTHOR]

Polyvinyl chloride (PVC) is involved in diverse applications that significantly influence our daily lives; it is industrially synthesized in various configurations in order to fulfill the target application. However, PVC is susceptible to photodegradation, yielding toxic byproducts detrimental to both the environment and human health, which diminishing its utility lifespan. Addressing this concern, current research explores the application of metal complexes as potential photostabilizers to mitigate PVC photodecomposition. The objective of this study is to investigate the effectiveness of formulated metal complexes in preventing photodegradation. Five metals, namely Cu(II), Ni(II), Cd(II), Zn(II), and Sn(II), are included. Examining parameters, such as molecular weight attenuation, the formation of alkene-laden and carbonyl fragments, and the surface morphology alterations of PVC sheets subjected to irradiation are considered. Findings indicate that these metal complexes exhibit remarkable efficacy in decreasing the photodegradation of PVC, thus presenting a promising avenue for extending its functional longevity. The polymer containing Cd(II) complex unit showed the least damage in the PVC surface due to photoirradiation, followed by other complexes. [ABSTRACT FROM AUTHOR]

A 240‐mg single tablet has been developed with the focus of reducing the pill burden of the apalutamide daily dose of 240 mg (4 × 60‐mg tablets). An open‐label, randomized, single‐dose phase 1 study with a 2‐sequence and 2‐period crossover design in healthy men determined the bioequivalence of a 240‐mg single tablet versus the currently available 4 × 60‐mg tablets (Part 1, N = 74) and assessed effect of a high‐fat meal (Part 2, N = 21) on apalutamide maximum plasma concentration (Cmax) and the area under the plasma concentration‐time curve (AUC0‐72 h). The 90% confidence interval of geometric mean ratios for Cmax and AUC0‐72 h fell between 80% and 125% for both Part 1 and Part 2. No new safety concerns with the 240‐mg single tablet were observed. To support the use of different food vehicles as well as nasogastric (NG) tubes for alternative administration, we conducted in vitro compatibility studies to evaluate the purity, dose, and stability of 240‐mg tablets dispersed in applesauce/yogurt/orange juice/green tea as well as in NG tubes (polyurethane/silicone/polyvinyl chloride). The studies confirmed the alternative administrations do not affect the purity, dose‐accuracy, or stability of apalutamide. The apalutamide 240‐mg tablet is bioequivalent to 4 × 60‐mg tablets and compatible with the tested food vehicles and NG tubes. [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]

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]

The article presents the design of Complibot, a robot with a novel gripper for pipe climbing. The mechanism of the gripper involves the use of a bistable buckled beam, which is a type of bistable compliant mechanism. The bistable buckled beam in the gripper is alternately actuated between its gripped and ungripped states using a camshaft and lever mechanism, which is powered by a single DC motor. The design parameters associated with the gripper are obtained both experimentally and numerically. A proper selection of design parameters helps in the efficient functioning of the gripper. After the design of the gripper, two such grippers are fabricated and attached to each other by two stepper motor-driven lead screws to make a pipe climbing robot with inchworm locomotion. The mobility of the robot is controlled by an Arduino Uno microcontroller after the electronic components have been integrated. Finally, Complibot is subjected to a series of tests to establish its maximum load-carrying capacity when climbing a polyvinyl chloride (PVC) pipe. Complibot is found to perform satisfactorily without slipping while climbing a PVC pipe with a diameter of 105–115 mm, a velocity of 0.2 m/min, a power consumption of 18.58 W, a maximum load-carrying capacity of 114.64 N, and a payload to weight ratio of 0.52. [ABSTRACT FROM AUTHOR]

Surface‐enhanced Raman spectroscopy (SERS) is a powerful analysis technique, and the SERS sensitivity is strongly dependent on metallic nanogaps with a greatly enhanced local electromagnetic field (i.e., hot spots). Once the analytes are located in the hot spot region, their Raman signals are enormously amplified. However, delivering analytes into such tiny hot spots remains a great challenge, particularly for molecules with small Raman scattering cross‐sections and no metal affinity. Here, by employing the isotropic contraction characteristics of polyvinyl chloride (PVC) when heated, a molecule trapping and SERS sensing strategy is demonstrated based on a large‐area ordered gold‐coated polystyrene nanospheres (PS@Au NSs) array with well‐controlled gap size assembled on PVC sheet. Compared with the traditional contraction‐adsorption mode, the developed adsorption‐contraction mode enables efficient delivery of analytes with or without metal affinity into the hot spots between the PS@Au NSs, leading to a significantly improved SERS performance with a large SERS enhancement factor of ≈3.57 × 107. The contractible SERS substrate exhibits a high sensitivity of 10−12 m for rhodamine 6G (R6G), 10−10 m for thiram, and 5 × 10−6 m for 2,3,4‐trichlorobiphenyl, as well as good signal reproducibility with relative standard deviations of 2.81% and 4.25% for R6G and thiram, respectively. [ABSTRACT FROM AUTHOR]

Migration of conventional petrochemical plasticizers can negatively affect the performance of plasticized products, human health and the environment and result in the reduction of petroleum resources. Thus, the development of bio-based plasticizers with migration resistance is very critical. In this study, two novel bio-based plasticizers with different structures derived from ricinoleic acid, i.e., epoxy acetylated benzyl ricinoleate (EABR) and epoxy acetyl terephthalate ricinoleate (EATPR), with good plasticizing effect and migration resistance were synthesized and characterized. The structure of EABR and EATPR was confirmed using FTIR and 1H NMR spectroscopies. The mechanical, thermal, and migration properties of the PVC samples plasticized with EABR and EATPR were extensively investigated, and the commercial plasticizer dioctyl terephthalate (DOTP) was used for comparison. The plasticized PVC samples with EABR and EATPR showed similar impact strength, elongation at break, and glass transition temperature (Tg) to DOTP-plasticized samples, indicating a good plasticizing effect on PVC. Furthermore, EABR and EATPR demonstrated superior performance in migration and volatility tests compared to DOTP. Besides, the plasticizing properties of the plasticized PVC were very sensitive to the structure of the plasticizer; EATPR, with a symmetric structure, showed better plasticization and plasticizing efficiency than EABR, with an asymmetric structure. In conclusion, the two bio-based plasticizers derived from ricinoleic acid showed attractive potential as alternatives to phthalate plasticizers, especially EATPR, with a larger symmetric molecular structure and higher aliphatic content. [ABSTRACT FROM AUTHOR]

Polymer blends of polyvinyl chloride/nitrocellulose/MoS2‐Nafion (PVC/NC/MoS2‐Nafion) were prepared using a casting technique. FTIR analysis revealed chemical interactions between the polymer matrix and filler. XRD analysis was employed to investigate changes in structural phases, while SEM illustrated the agglomerated morphology of the modified blends. The critical role of ionic interaction between Nafion and polymer system in enhancing electrical properties was confirmed through impedance analysis. The introduction of oxygenated functionalities improved surface topography and roughness, as observed by AFM. Electrical conductivity increased from 10−6 S/cm to 10−4 S/cm, accompanied by a decrease in activation energy (Ea). The addition of Nafion decreased bulk resistance, indicating enhanced ionic mobility, as supported by impedance analysis. TG‐DSC analysis demonstrated that MoS2 and Nafion improved thermal properties of polymer blends. The glass transition temperature (Tg) increased by approximately 13 °C and 21 °C with MoS2 and Nafion, respectively. Universal testing machine (UTM) results indicated moderate tensile strength and Young's modulus achieved by MoS2 and Nafion. With increasing Nafion loading, elongation at break rose to around 71 %, showcasing excellent interfacial interaction in polymer‐filler system. The resulting polymer blends, modified by Nafion, exhibited high ionic/electrical conductivity and show promise for hybrid polymer electrolyte applications. [ABSTRACT FROM AUTHOR]

Highlights This paper calculates the crashworthiness capability of glass‐reinforced epoxy composites over wrapped polyvinyl chloride (PVC) circular tubes with a triggering mechanism in the form of cutouts. The intended tubes were prepared by a wet wrapping method; after which they were subjected to quasi‐static axial compression. To compute crashworthiness indications, three design parameters, each at three levels, were used. The design parameters are the hole diameter (d), the hole's number (n), and the hole position (L). The Taguchi technique has been employed in the design of experiments (DOE) tactic to obtain the best crashworthiness parameters. With the maximum specific energy absorbed (SEA) and crashing force efficiency (CFE), the optimal parameters were found. Furthermore, the main effect, signal‐to‐noise ratio (S/N), as well as the analysis of variance (ANOVA), have been studied using the commercial software programme MINITAB 18. A few experiments were accompanied by the L9 orthogonal array. According to the results, “N” has the largest impact on the value of SEA with a contribution percent of 29.27%. While “d” has the main influence on the value of CFE with a contribution percent of 67.29%. Lastly, tests for confirmation were performed. to verify the predicted values in light of the experimental results. The optimized SEA developed tube is 74.72%, which is higher than the intact PVC tube and 12.29% lower than the intact hybrid tube. However, the optimum CFE was also 48 and 29.82% higher than the intact PVC tube and the intact hybrid tube, respectively. The number of holes has the highest impact on SEA value by 29%. The ideal specimen enhances SEA by 75% compared to the intact PVC tube. Hole diameter has the most influence on CFE value by 67%. The best specimen improves the CFE by 48% related to the intact PVC tube. [ABSTRACT FROM AUTHOR]

The accumulation of high amounts of plastic waste in the environment has raised ecological and health concerns, particularly in croplands, and biological degradation presents a promising approach for the sustainable treatment of this issue. In this study, a polyvinyl chloride (PVC)-degrading bacterium was isolated from farmland soil samples attached to waste plastic, utilizing PVC as the sole carbon source. The circular chromosome of the strain Cbmb3, with a length of 5,768,926 bp, was subsequently sequenced. The average GC content was determined to be 35.45%, and a total of 5835 open reading frames were identified. The strain Cbmb3 was designated as Bacillus toyonensis based on phylogenomic analyses and genomic characteristics. The bioinformatic analysis of the Cbmb3 genome revealed putative genes encoding essential enzymes involved in PVC degradation. Additionally, the potential genomic characteristics associated with phytoprobiotic effects, such as the synthesis of indole acetic acid and secondary metabolite synthesis, were also revealed. Overall, the present study provides the first complete genome of Bacillus toyonensis with PVC-degrading properties, suggesting that Cbmb3 is a potential strain for PVC bioremediation and application. [ABSTRACT FROM AUTHOR]

We report on the energy deposition of ultrashort laser pulses with two different intensities of 6 TW cm - 2 and 143 TW cm - 2 in polyvinyl chloride, using two-color pump-probe shadowgraphy. The interaction is imaged during the pulse propagation into the medium and up to 200 μ s after. The shadowgraphs show that higher-intensity pulses induce significantly more ionization of the material. Furthermore, it is shown that lower-intensity pulses propagate over the entire visible range of the shadowgraph without major losses, while higher-intensity pulses fade significantly after about 200 μ s . After the interaction, pulses of both intensities produce a similar temperature-induced shadowgraphy pattern. The observations of the ionization process, the propagation of the pulse in the medium, and the thermalization are explained based on theory regarding ultrashort pulse laser interaction with dielectrics. Furthermore, the ablation craters produced by multiple consecutive pulses of both intensities are compared. The crater produced with lower-intensity pulses shows trails of material change significantly below the ablation crater, while these trails do not exist when using pulses with higher intensity. This is attributed to the differences in pulse propagation observed in the shadowgraphs of single pulses. This work demonstrates, for the first time, the intensity dependence of energy deposition of ultrashort laser pulses in polyvinyl chloride and its consequences for laser micromachining. [ABSTRACT FROM AUTHOR]

Polyvinyl chloride (PVC) foam, valued for its mechanical and thermal properties along with cost-effectiveness, is extensively utilized across diverse industries. However, its high volatile organic compound (VOC) emissions hinder its adoption in eco-friendly synthetic leather. This study proposes a solution by optimizing the formulation design and foaming processes and achieving mechanical property enhancement via carbon-fiber-reinforced PVC composite foam (CF/PVC). The aim is to reduce PVC usage via enhancing its intrinsic properties. Systematic investigations were carried out on the impact of foaming raw materials, foaming processes, fiber content, and fiber length on the foaming performance, mechanical properties, and VOC emissions. The material formulation and process parameters were successfully optimized. Further assessment of various indicators such as the density, mechanical properties, and tear resistance of synthetic leather samples confirmed that the innovative CF/PVC foam developed in this study meets the requirements for automotive interior applications. Notably, the tensile strength and tear resistance of CF/PVC composite synthetic leather increased by 50% and 29%, respectively, compared to pure PVC, while VOC emissions decreased by 28%. It is anticipated that a more pronounced reduction in VOC emissions will be achieved in practical automotive interior leather applications when further considering the reinforcing effect of fibers, which leads to a reduction in PVC usage. The findings present a technical reference for innovative applications, aiming to enhance PVC foam performance and minimize emissions. [ABSTRACT FROM AUTHOR]

Polyvinyl chloride (PVC) is a kind of plastic widely used in different industries, and it is a hard and brittle polymer that requires the use of plasticizers to improve processability. Phthalates are small molecule plasticizers of PVC, which are easy to volatilize and migrate while improving the processing properties of PVC. We propose alternatives based on phenolic resin prepolymer modified by cardanol (CPF), which were added to PVC as reactive plasticizer and can improve the processability of PVC. The effects of CPF on the rheological properties and migration resistance of plasticized PVC were studied, and the changes in the physical properties of blends were also discussed. The results showed that the viscosity of PVC melt can be reduced by two orders of magnitude by adding 30 wt% prepolymers at 180°C compared with PVC without CPF, which indicated that CPF can be used to reduce the processing temperature of PVC. The test results of migration resistance showed that the mass loss rate of the blend with 30 wt% prepolymers was less than 1 wt% after curing, however, the mass loss rate of the blend with 30 wt% dioctyl phthalate (DOP) was more than 12% after 5 days of testing. When the PVC/CPF mass ratio was between 60/40-70/30, the maximum values of tensile strength and elastic modulus are 64.4 MPa and 3.2 GPa, respectively, which showed the addition of CPF could significantly improve the tensile strength and elastic modulus of the blend system compared with PVC without CPF. Especially, the thermal stability of CPF is better than that of DOP, CPF exhibits the maximum thermal decomposition temperature (410°C), higher than that of DOP (170°C), which can adapt to higher processing temperature. [ABSTRACT FROM AUTHOR]

In this research, a solvent thermal dechlorination method was adopted to remove chlorine from polyvinyl chloride (PVC) material, using ethylene glycol (EG) as solvent and adding alkaline additives, so as to improve the dechlorination efficiency and reduce the reaction temperature. KOH, NaOH and K 2 CO 3 were selected as additives and their dechlorination activity was found to decrease in the following order: K 2 CO 3 >KOH>NaOH. Afterward, the effect of K 2 CO 3 concentration, reaction temperature and reaction time on the dechlorination of PVC was studied and a novel dechlorination mechanism was investigated. The results showed that solvothermal dechlorination may accomplish efficient dechlorination at low temperatures. The reaction temperature can be reduced to 180 ℃ in 0.5 M K 2 CO 3 /EG system with a solid-liquid ratio of 1:40(g:ml) and more than 97% dichlorination, which is 10 ℃ lower than the lowest temperature reported in published literature. Through the characterization and analysis of solid products, the dechlorination mechanism of PVC in K 2 CO 3 /EG system was proposed. Glycolate ion and OH- may be formed in the reaction and they both work to dechlorinate PVC by removing the Cl through two distinct substitution reactions. [Display omitted] [ABSTRACT FROM AUTHOR]

This paper describes both an experimental study and a numerical investigation on the compressive behavior of new types of solid as well as hollow composite columns, which consist of Unplasticized Polyvinyl Chloride (UPVC) tubes filled with expansive concrete. 32 specimens were categorized into four groups and cast with expansive concrete. Half of the specimens were confined additionally with two layers of GFRP wraps. Furthermore, two specimens were cast with ordinary concrete to be compared with those expansive counterparts. All the composite columns were tested under the monotonic compressive loading. The effects of GFRP confinement, aspect ratio of composite columns (L / D), and hollowness of concrete core on compressive behavior were investigated. It was demonstrated that adding expansive agents improved the load-carrying capacity and ductility of columns by enhancing the tri-axial state of stress in the concrete core. Moreover, an increase in aspect ratio decreased both peak load and its corresponding axial strain. Approximately 40% increase was observed in the values of peak load for specimens confined with GFRP wraps. Generally, concrete core removal in the hollow specimens resulted in slightly higher average compressive stress. Finally, a finite element (FE) simulation was performed using ABAQUS software, and the numerical results were validated with experimental tests of the present study. [ABSTRACT FROM AUTHOR]

In this work, it was proposed to introduce non-stoichiometric nano cadmium sulfide (CdS1-x) nanoparticles into polyvinyl chloride (PVC) polymer using simple, environmentally friendly and low-cost techniques. Undoped and doped PVC polymers with non-stoichiometric CdS1-x were formed using casting and thermolysis procedures. Rietveld refinement was applied to identify the phases formed and microstructure parameters in non-stoichiometric CdS1-x. Different techniques were used to investigate the structure, morphology, optical properties and dielectric of polymer films. The direct and indirect optical band gap (Eg) values of the undoped PVC film are 5.63 eV and (5.22, 4.49, 3.51) eV. As the sulfur concentration in the nanofiller increased to 97%, the direct and indirect Eg values of the CdS1-x doped polymers decreased to (5.21, 4.07, 2.44) eV and (4.18, 2.3, 2.03) eV, respectively. The optical dielectric constant and optical conductivity reached their maximum values as the amount of sulfur reached 97% in CdS1-x. Doped polymers are effective materials against UVA, UVB, and UVC spectra and work very well as solar cell absorber materials. The CIE 1931 chromaticity diagram revealed that PVC shifted from blue color to green-yellow and yellow-orange regions under excitation wavelengths of 317 and 380 nm, respectively. The electrical dielectric constant reached its maximum value when the sulfur content of the nanofiller reached 95%. AC conductivity has its maximum value when PVC is loaded with CdS0.9. The manageable optical and electrical features show that PVC/CdS1-x polymers could be potential optical materials in the development of futuristic flexible-type optoelectronic devices. [ABSTRACT FROM AUTHOR]

• Geographic and technical matching approach was proposed for PW recycling. • This optimization could aid in accelerating achievement of carbon neutrality. • Mechanical/material recycling should be prioritized at current technical level. • Technical parameters were prioritized over geolocation for more CO 2 reductions. • The emission reductions per ton of PVCW disposed increased in future scenario. This study provided a geographic and technical matching approach supporting low-carbon style recycling systems, demonstrated using polyvinyl chloride waste (PVCW) generated in 2018 in Mie Prefecture, Japan. From a carbon dioxide (CO 2) emission basis, mechanical/material recycling (MR) and energy recovery facilities were all allocated full capacity; however, parts of chemical recycling facilities were excluded in the optimal solutions. From the spatial distribution of the allocated result, we confirmed a trend that to achieve the minimum total emissions, the matchings from pretreatment to recycling facilities were done based on a nearby priority rule. From an emission reduction basis, MR accounted for the major proportion of total reductions which was similar to that accessed from an emission basis. Thus, the promotion of MR should be prioritized at the current technical level when optimizing emissions of the whole lifecycle. The number of facilities allocated were substantially reduced; meanwhile, the averaged emission reductions per ton of PVCW disposed were increased from the current level (2.93) to the near-future level (4.99 t-CO 2 t−1). Thus, we concluded that this optimization under a higher technical level was effective to make the current recycling system with more emission reductions (low-carbon environmental effect) and require fewer disposal facilities (cost-saving economic effect). Meanwhile, certain long-distance routes found in solutions implied that technical parameters were more important than geolocation parameters to achieve maximum emission reductions. [ABSTRACT FROM AUTHOR]

The accumulation of high amounts of plastic waste in the environment has raised ecological and health concerns, particularly in croplands, and biological degradation presents a promising approach for the sustainable treatment of this issue. In this study, a polyvinyl chloride (PVC)-degrading bacterium was isolated from farmland soil samples attached to waste plastic, utilizing PVC as the sole carbon source. The circular chromosome of the strain Cbmb3, with a length of 5,768,926 bp, was subsequently sequenced. The average GC content was determined to be 35.45%, and a total of 5835 open reading frames were identified. The strain Cbmb3 was designated as Bacillus toyonensis based on phylogenomic analyses and genomic characteristics. The bioinformatic analysis of the Cbmb3 genome revealed putative genes encoding essential enzymes involved in PVC degradation. Additionally, the potential genomic characteristics associated with phytoprobiotic effects, such as the synthesis of indole acetic acid and secondary metabolite synthesis, were also revealed. Overall, the present study provides the first complete genome of Bacillus toyonensis with PVC-degrading properties, suggesting that Cbmb3 is a potential strain for PVC bioremediation and application.

Due to its versatile properties polyvinyl chloride (PVC) based materials are employed in several applications. At high temperatures and in acidic media PVC is prone to release toxic materials into the environment. Several reports are available in the literature about the modification of PVC to minimize such problems. Herein, an attempt is made to prepare PVC/Halloysite nanotube (HNT) nanocomposites with a fixed amount of compatibilizer, OPTIM GE 344 (maleic anhydride modified very low-density polyethylene (VLDPE)) and characterize the composites with respect to thermal stability, mechanical properties, and structural aspects. Both tensile and flexural strength showed appreciable improvement for the 4 wt% loading of the nanofiller. Thermogravimetric analysis (TGA) showed that the maximum degradation temperature improved by approximately 24 °C for 4 wt% filled composites. PVC thermomat measurements of the samples were used to study the thermal stability of the composites. PVC without HNT showed 36 min as the stability time and it increased to 398 min for 4 wt% of HNT loading. To complement the thermal properties of the composites, the mass loss measurement and contact angle behavior of the composite surfaces were also done. The decrease in contact angle values denoted better surface wettability properties. The mass loss measurements showed a decrease with respect to the filler loading of HNT, indicating a better interaction between the polymer matrix and HNT.

Abstract Polyvinyl chloride (PVC) is one of the most important commercial plastics but it is thermally unstable at processing temperatures. Therefore, heat stabilizers are widely used to safeguard by improving resistance of PVC products at high temperature. But most of them are a highly toxic that can cause severe health issues in humans and harmful to the environment. In the present study mixed of calcium/zinc stearate heat stabilizer and green Expandable graphite (EG) is prepared via hydrothermal treatment using additives of nontoxic, environmental protection. The characteristics of the thermal stability of poly vinyl chloride can be investigated by Scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) will be used to examine structure of the heat stabilizers, A universal testing equipment will be used to determine the mechanical properties and thermal gravimetric analysis (TGA). From TGA results the weight loss was 43.49% at 342°C for sample with Ca/Zn‐ stearate, while wt loss is 55.87% at 260°C for sample with EG which increase thermal stability. Differential scanning calorimetry affirmed the enhancement of PVC's thermal stability, showing a shift in the glass transition temperature an increase of 67°C. Mechanical tests indicated that samples with EG exhibited higher tensile strength and elongation at break, emphasizing the positive impact on PVC's mechanical properties. The burning test highlighted thermal stability of EG‐containing samples, retaining color and structure even after exposure to 180°C heat. This innovative approach not only enhances thermal stability but also aligns with eco‐friendly principles, making it a promising solution for improving PVC properties. Highlights Ca/Zn‐ stearate, expandable graphite developed by a safe hydrothermal process. Comprehensive analysis indicates improved thermal stability. Safe stabilization of eco‐friendly calcium/zinc, expandable graphite. Effective solution: Eco‐friendly, improved PVC properties. Expandable graphite improved mechanical properties of PVC.

ABSTRACT: Introduction. The application of nanocomposites in various industries has increased in recent years due to their unique properties and performance characteristics. Enhancing the quality performance of nanocomposites presents a formidable challenge, primarily attributable to the intricate interactions among their constituent elements. This paper presents an overview of the methods used to analyze and calculate the quality performance of nanocomposites using PVC as the base material. Methods and materials. To calculate technological parameters that are not directly measurable, we conducted a thorough analysis of literature sources related to the specific process under consideration. Through this analysis, we established appropriate relationships between empirical data in accordance with the fundamental principles of thermodynamics and mass transfer processes. In the course of the research, the method of neural networks was applied in order to describe the process of vinyl chloride polymerization carried out by suspension method. To solve this problem, a cascade network with forward propagation of the signal and backward propagation of the error was applied. Network composition: in the hidden layer – ten sigmoid neurons, in the output layer – two linear neurons. Results and Discussion. Throughout this research, it was observed that the heat flux during polymerization exhibits temporal variation, contingent upon the concentration level of the initiator. Further the dependencies obtained can be used in controlling the flow rate of refrigerant into the reactor cooling jacket, to ensure that the entire process is isothermal. It was found that by varying the stirrer speed, it is possible to change the particle size and hence the molecular weight distribution of polyvinyl chloride. The developed neural network was tested. The obtained results have minimal error and are close to the real values, from which we can conclude that the network is trained correctly and the dependence between the data is found. Conclusion. Dependencies linking physicochemical parameters of the technological process with the design features of the apparatus have been established. To maintain the quality of PVC, in particular the appropriate molecular weight distribution, a neural network (a cascade network with direct signal propagation and reverse error propagation, consisting of ten sigmoidal neurons in the hidden layer and two linear neurons in the output layer) was developed in MATLAB environment. The network was trained on a sample and tested on test values, which showed that the network predicts the outcome of the process with minimal tolerable error, with other parameters unchanged.

Health-care-associated infections (HAIs) can occur if a contaminated product bypasses current tests and prophylactic measures. These contaminations may be missed due to low bacterial loads or the presence of adhered biofilms. Antibacterial coatings applied inside blood storage bags or onto medical devices are promising to further reduce the residual risk of HAIs. The aim of this study was to optimize the antibacterial efficacy of a polymer — polydopamine — as a potential material for the prevention of transfusion-transmitted bacterial infections. When varying the concentration of dopamine monomers (1-3 mg/mL), the sample position (horizontal vs vertical), the stirring speed (0–90 RPM) and the reaction time (0.5 – 24 h), the morphology and wettability of the coatings were modified as determined by UV–visible (absorbance 0.013 – 0.562 at 320 nm), wettability (contact angle 35 – 61 °C) and atomic force microscopy measurements (total roughness 6 – 140 nm). The resulting cytotoxic (< 6%) and antibacterial behaviors (< 90 – 99% bacterial reduction) of the coatings were determined using ISO-10993–5 and ISO 22196 standardization. Coatings with good thickness and roughness had optimal antibacterial effects against Staphylococcus aureus (1.6 ± 0.4 log reduction), although minimal reduction was measured against Escherichia coli (0.05 log reduction). The antibacterial efficacy of polydopamine appears to be linked to its thickness and roughness, two parameters that may affect the surface wettability and, in turn, bacterial adhesion. Based on these results, polydopamine could be employed to help limit HAIs, although its antibacterial properties need to be further improved depending on the nature of bacteria and the requirements of the applications.

Microplastics (MPs) are environmental pollutants and can be inhaled by humans to threaten health. The lung tissue, responsible for the gas exchange between the body and the environment, is vulnerable to MPs exposure. However, from the perspective of cellular senescence, the effect of MPs on lung cells and tissues has not yet been deeply dissected. In this study, we reported that all the four typical MPs exhibited the significant biological effects in term of inducing senescence of human lung derived cells A549 and BEAS-2B in vitro. We further found that polyvinyl chloride (PVC) increased the reactive oxygen species (ROS) level in A549 cells and that PVC-induced senescent characteristics could be largely reversed by antioxidant treatment. Importantly, intratracheal instillation of PVC MPs in mice could effectively impair their physical function, induce the increased systemic inflammation level, cause the accumulation of senescent cells. Our study demonstrates that MPs induce senescence in human lung epithelial cells and mouse lungs by activating ROS signaling, and provides new insight into the potential pathogenesis of MPs on lung diseases.

AbstractPolymethyl methacrylate (PMMA)/Congo Red (CR) and polyvinyl chloride (PVC)/CR composite films were prepared on optical glass by the drop method for optical measurements and also prepared as tablets under pressure for dielectrical measurements. The optical transmission spectra measurements for PMMA and PVC film doped with CR showed a highly absorption in the ultraviolet-visible (UV-Vis) optical range (at 353 nm and 518 nm) and considerably blocking in broad visible range (190 nm–640 nm). PMMA/CR and PVC/CR composite films containing congo red at a concentration of 1 wt% showed maximum absorption bands at 290 nm and 416 nm, but their transmittance percentages were reasonably reduced compared to those of pure PMMA and PVC. Both of composites indicated high transmittances between 640 nm and 800 nm. The optical constants of the PMMA/CR and PVC/CR composite films such as optical band energy gaps (Eg) estimated using Tauc’s model, refractive index and reflectance (%) were calculated. UV–Vis, Fourier transform infrared spectroscopy (FTIR) and Thermogravimetry Analysis (TGA) measurements were used to confirm the breakdown of the -N = N- azo group bonds attached to the aromatic ring as a result of thermal decomposition of CR at 500 °C, and it was suggested that N2 gas was eliminated from the CR above 360 °C. The dielectric plots showed that the dielectric constant increased when the CR is doped up to 70 wt% in the polymer matrices. A further increase in the doping concentration of CR resulted in an increase of the dielectric constant. The dielectric constant decreased with an increase in the frequency for all of the samples. The ac (alternating current) conductivity values of PMMA and PVC showed an increase with increasing CR dopant in the polymer composites, while the ac conductivity values were found to be values between those of the pure polymers and CR. [ABSTRACT FROM AUTHOR]

Replicated studies are advantageous for optimizing larval rearing of the Eastern oyster (Crassostrea virginica) and increasing the availability of high-quality seed for the continued expansion of the U.S. oyster aquaculture industry. Although small-scale systems using live algal feeds have been used successfully, rearing larvae on algae concentrate presents additional challenges. To determine the feasibility of rearing oyster larvae in small-scale systems using algae concentrate, oyster larvae were raised for 2 weeks in replicate control (1,000 L) and microcosm (17 L) tanks. Five aeration strategies were tested in the microcosms in two separate trials. Results of this study indicate similar survival in small systems compared to controls through the appearance of eyed larvae. Accumulated algae and pink biofilm formation in microcosms using polyvinyl chloride (PVC) airlifts suggest that this aeration strategy is undesirable. One- and 5-mL air injectors maintained higher overnight oxygen levels than controls. The recovery of more eyed larvae after 14 dpf in control systems may be the result of significant temperature fluctuations in microcosms. Overall, this study demonstrates that algae concentrate can be used to rear oyster larvae in small-scale systems, providing a live feed alternative that saves space and labor in replicated studies. [ABSTRACT FROM AUTHOR]

Polyvinyl chloride remains one of the most prevalent polymers in the industry, yet its substantial environmental impact, attributed to its fossil origin, prompts the exploration of innovative solutions. Composites, particularly bio-composites, emerge as promising alternatives to mitigate the ecological footprint of PVC while enhancing its characteristics. This study addresses this concern by presenting the development of a bio-composite comprising 90% PVC and 10% biological filler derived from bovine horn, renowned for its high keratin content. The primary objective was to create an innovative, environmentally friendly, and sustainable material. To rigorously assess the properties and thermal stability of this bio-composite, a comparative thermogravimetric analysis was conducted against virgin PVC. The results reveal the superior thermal stability of the biocomposite compared to virgin PVC, particularly beyond 280 ℃. This enhancement is attributed to the substantial presence of keratin in the biological filler, constituting nearly 90% of the horn biomass. Notably, the observed mass loss in the bio-composite is lower than that of virgin PVC at temperatures exceeding 280?. This research underscores the potential of bio-composites, specifically those incorporating bovine horn-derived filler, as promising alternatives to mitigate the ecological footprint of PVC while concurrently improving its thermomechanical characteristics. The innovative material developed in this study holds promise for sustainable applications in various industries, aligning with the growing demand for environmentally conscious alternatives. [ABSTRACT FROM AUTHOR]

Droplet collectors are commonly utilized to gauge the effect of pesticide deposition on crops. However, the varying surface characteristics of these collectors can lead to disparate data outcomes. Notably, water-sensitive paper is limited in humid environments, hindering rapid droplet deposition evaluation. Consequently, the selection of appropriate droplet collectors based on the environmental conditions is imperative. This study involved the use of five typical droplet collectors to establish a method for the swift and accurate evaluation of spray effectiveness, employing various spray liquids. It was observed that the surface free energy of five widely used droplet collectors was measured as follows: 35.11 mN m−1 for semigloss paper, 33.81 mN m−1 for coated paper laminated with polyvinyl chloride, 48.38 mN m−1 for kromekote paper (KP), 33.90 mN m−1 for polyvinyl chloride cards, and 39.95 mN m−1 for water-sensitive paper. When comparing the outcomes of deposition tests across these five collectors, it was noted that the results pertaining to droplet density were minimally influenced by the surface properties of the collectors with droplet coverage following. The volume of deposition was found to be the most susceptible to the surface characteristics of the collectors. Therefore, in the context of collecting and processing droplets, prioritizing droplet density as the metric for evaluation proved to be more reliable than using the other indicators. [ABSTRACT FROM AUTHOR]

Recycling materials has become an immerging tendency as a way for preserving natural resources. The waste disposal of polymeric materials has a significant impact on the environment and public health through their practical application in civil engineering constructions. The current experimental study aims to investigate the possibility of using polyvinyl chloride (PVC) waste in concrete and also to evaluate the PVC concrete properties in comparison with ordinary concrete (OC). This investigation research involves reusing the left-over PVC tube wastes and their incorporation in concrete. Three different replacement ratios (5%, 10% and 15%) of natural sand by polyvinyl chloride were considered, taking into account two different sizes (fine and fiber) of polymeric wastes. The effects of each incorporated PVC waste on the compressive strength, and tensile strength were studied. The fresh properties of concrete were investigated by conducting a slump test. The results revealed a decrease in the workability of the fresh PVC concrete compared to ordinary concrete. It was observed that the concrete made with fiber PVC shows a lower workability (decrease of 54%) in comparison with the first one which contains fine PVC aggregates. The concrete made with fiber PVC aggregates improves the compressive strength up to 23.5%. This latter increased simultaneously with increasing the replacement ratio of PVC waste. However, the increase of fine PVC waste content caused a decrease in compressive strength till 21%. The test results also revealed that the concrete mixes with high fiber and moderate fine PVC ratios enhanced the concrete mechanical performance. [ABSTRACT FROM AUTHOR]

This study investigates the impact and after-impact compression behavior of sandwich structures with carbon fiber composite face-sheets consisting of various polymeric core structures. In particular, the performance of polypropylene foam core with closed cell structure, which is new to engineering applications, against other polymeric core structures was investigated. Sandwich panels were subjected to three different impact energies and after-impact compression tests were conducted on each sample to reveal their damage tolerances and load-carrying capabilities. In-situ acoustic measurements were made to fully understand the damage and evolution mechanisms in the after-impact compression tests. Honeycomb polypropylene (PP) foam, polyvinyl chloride (PVC), and extruded polystyrene (XPS) foam were used as core materials. As a result of the tests, it was obtained which damage types occurred at which force levels. PP core panels exhibited different impact behavior compared to conventional sandwich core structures and were successful in preventing damage to the face sheets. [ABSTRACT FROM AUTHOR]

• Latest trends and challenges in PVC and copper recovery technologies from thin cables. • Current technologies prioritize copper recovery, PVC recovery is low-priority. • Physical treatments alone cannot achieve high-purity PVC recovery from thin cables. • Combined chemical and physical treatments enable high-purity PVC and copper recovery. • Next-generation solutions for proper management of thin end-of-life cables. This review investigates the latest trends in separation technologies regarding hard-to-recycle thin cables, specifically in the form of end-of-life wire harnesses (WHs). The cables in WHs mainly contain copper (Cu) and poly(vinyl chloride) (PVC), which is commonly used to insulate and sheath cables. This review reveals that most separation technologies prioritize the recovery of Cu and overlook that of PVC. The recovery of high-purity PVC is very important because of its incompatibility with other plastics or Cu during recycling treatments. Through this investigation, we confirm that physical treatments, such as stripping and chopping, are insufficient to recover high-purity PVC from thin cables. Instead, a combination of chemical (e.g., swelling of PVC insulation or sheathing of cables under a suitable solvent) and physical (e.g., ball or rod milling and mechanical agitation of swollen cables) treatments can be used to achieve the recovery of high-purity PVC and Cu both for recycling. We believe that recovering metals and plastics from end-of-life cables is vital for sustainable waste management, offering several environmental and economic benefits. [ABSTRACT FROM AUTHOR]

The present research paper investigates the chemical, thermal, mechanical, thermo‐mechanical properties, and fractography of sandwich composites made from E‐glass‐reinforced isophthalic polyester with Poly Vinyl Chloride (PVC) foam as a core by hand. These composites are commonly used in marine applications and manufactured by hand lay‐up method. A comparison is made between the properties of the PVC foam polyester sandwich composite with E‐glass layers on both sides (SC1) and the PVC foam isophthalic polyester sandwich composite with double layers of E‐glass on both sides (SC2) in relation to single‐layer E‐glass. Fourier transform infrared (FTIR) spectroscopy is employed to analyze the chemical composition of the composites. Various mechanical properties, including impact strength, flexural strength (FS), fracture toughness, and tensile strength (TS), are evaluated for the fabricated composites. Thermo‐mechanical and thermal properties are examined using dynamic mechanical analysis and thermogravimetric analysis (TGA), respectively. The chemical analysis identifies the unsaturation sites of (CH2)n, carbonyl group CO of the ester group, and the stretching of CH and CH3. The mechanical properties of SC2 composites are observed to be superior to those of SC1 composites. TGA revealed that both SC1 and SC2 composites showcased comparable temperature‐dependent weight loss patterns. Nonetheless, the SC2 composite displayed elevated glass transition temperature values and superior damping properties, as indicated by its higher Tanδ values. Examination of the fractured surfaces using a scanning electron microscopy (SEM) micrograph reveals a honeycomb structure, matrix cracking, and fiber pullout. Highlights: Examination of the chemical, thermal, mechanical, and thermo‐mechanical attributes of sandwich composites made from E‐glass‐reinforced isophthalic polyester with PVC foam as the core.Evaluation of the impact of E‐glass layering on the thickness of the composite skin.Analysis of interfacial properties through FTIR techniques.Assessment of mechanical properties like impact strength, FS, fracture toughness, and TS.Investigation of fracture surfaces using SEM. [ABSTRACT FROM AUTHOR]

Novel magnetic ionic polymers based on polyvinyl chloride ([PVCs][FeCl4]) with liquid-crystalline (LC) ordering were synthetised and characterised. The [PVCs][FeCl4] containing magnetic tetrachloroferrate ions were prepared with PVC, pyridyl LC monomers and FeCl3. Various devices and instruments were used to characterise the chemical structure, thermal behaviour, magnetic properties, and LC properties. The synthetised [PVCs][FeCl4] showed smectic LC phase and presented excellent thermal stability. Several magnetorheological (MR) fluids were prepared using [PVCs][FeCl4] as particles and silicone oil as carrier fluid. MR Effects and settlement stability were investigated. Under the condition of external magnetic field, the MR fluids showed Bingham flow characteristics, and the MR effect was enhanced with increasing FeCl4− content in the systems. Under the condition of magnetic field intensity of 80 kA/m and shear rate of 2.5 s−1, the magnetorheological efficiency of [PVCs][FeCl4] based MR fluids with particle concentration of 20% can reach up to 14.7. The excellent MR effect of [PVCs][FeCl4] was due to the strong coupling between the magnetic moment of the FeCl4− anion and the orientation of cationic LC primitive under the action of an applied magnetic field. Furthermore, the good settling stability of the MR fluids was due to the introduction of organic mesogens, PVC main-chains and the ionic components for the [PVCs][FeCl4] particles. [ABSTRACT FROM AUTHOR]

Background: The I-LMA ventilates while providing a port for blind insertion of an endotracheal tube. The ILMA Fastrach is used especially for intubating in a difficult airway scenario. Its accompanying endotracheal tube is not economical nor readily available. In comparison, two alternative endotracheal tubes – polyvinyl chloride and wire-reinforced tubes were used for tracheal intubation through the ILMA. Aims and Objectives: The aim of our study was to compare the ease of intubation when using conventional PVC tubes versus the wire-reinforced flexometallic tubes with the ILMA-FastrachTM. The number of attempts, time taken and additional maneuvers were noted. Intra-operative hemodynamic changes, post-operative sore throat, bleeding and hoarseness of voice was recorded over a period of 24 hours. Methodology: After informed consent, 60 ASA I-II patients undergoing elective surgeries under general anesthesia were allocated to undergo blind intubation with the PVC tube or the wire-reinforced flexometallic tube. Results: More attempts were required for successful intubation using the wire-reinforced tube than the PVC tube with 76.7% passing in the first attempt in the PVC, and 53.3% passing in the first attempt in the flexometallic group. (P = 0.4). Average time for intubation in the PVC group: 28.24 ± 7.22 seconds. Average time for intubation in the flexometallic tube: 45.8 ± 15.78 sec. Occurrence of post-operative sore throat was 13.3% in the PVC group and 26.6% in the flexometallic group, with minimal hoarseness of voice 3.3% in the PVC group and 10% in the flexometallic group. There was also a slightly higher hemodynamic response in those who were intubated with the flexometallic tube than a PVC tube. Conclusion: Intubating via the ILMA-Fastrach with the PVC tube offered better intubating conditions with regards to lesser time taken, lesser attempts, less manipulation, and less hemodynamic variations as compared to the patients who were intubated using the wire-reinforced tube. [ABSTRACT FROM AUTHOR]

Field observations of flow measurement difficulties using portable ultrasonic flow meters are reported in this work. Accordingly, pipe wall thickness and sensors' spacing were identified as two important sources of the in-situ flow measurement inaccuracies. Experimental tests were accomplished to evaluate the effect of input parameters on the performance of the portable ultrasonic flow meters. Iron and Unplasticized Poly Vinyl Chloride (UPVC) pipes of the outer diameters of 3, 4, and 8 inches were tested. For all tested cases, the pipe wall thickness increase would affect the ultrasonic performance more than the cases with the wall thickness decrease. A mixed effect of the sensors' spacing was observed for the changes in pipe material/dimensions. Finally, a correction equation was proposed to improve the flow measurements. [ABSTRACT FROM AUTHOR]

Polyvinyl chloride (PVC) is a polymer widely used in the world whereas safety problems owing to PVC aging are often reported. Thermal‐oxidative aging is known the main cause of its performance deterioration and lifetime decreasing. The existing PVC aging detection methods are complicated, making it difficult to achieve rapid on‐site diagnosis. The purpose of this paper is to evaluate the degree of PVC aging by means of terahertz technology. Samples were subject to thermal‐oxidative aging, and the corresponding dielectric spectra were measured by a terahertz time‐domain spectrometer. It turns out that the aging dependent dielectric spectra conforms to the physicochemical theory. Moreover, numerical correlation between the change in permittivity and the degree of aging, underlying a new solution for the aging forecast aimed at plastics. [ABSTRACT FROM AUTHOR]

Optically transparent dual‐band frequency‐selective surfaces (FSSs) are promising candidates to address the specific design challenges of the Internet of Things. This paper demonstrates their potential by discussing different configurations of the two single‐layer FSS designs on an innovative optically transparent polyvinyl chloride surface material. First, FSS cells consist of two cross dipoles placed forming angles of ±45∘ $\pm 4{5}^{\circ }$, where each rotated dipole structure parallel to the other. Then, in the second design, each one of the two cells is mirrored to enable polarization control for each band. As a proof‐of‐concept, five prototypes of each design having a unit cell size of 0.43λ0×0.43λ0 $0.43{\lambda }_{0}\times 0.43{\lambda }_{0}$ are fabricated through a combination of cost‐effective printing and shearing. The manufactured prototypes yield more than 93% transparency and robust dual‐band performance. Moreover, more than 20 and 40 dB isolation for lower‐ and upper‐frequency bands are achieved from the fabricated prototypes. High‐transparency, cost‐effectiveness, and robust high performance in terms of suppression make both structures suitable for sub‐6‐GHz fifth generation applications. [ABSTRACT FROM AUTHOR]

The rapid upgrading of electronic products led to the generation of a great deal of waste tantalum capacitors (WTCs). The recovery of WTCs is of great interest due to the high-value metal tantalum and resin materials. However, it is difficult to separate/recover the materials from WTCs because of the special structure and composition. Polyvinyl chloride (PVC) waste with high level of chlorine could result in severe corrosion and emission of chlorinated pollutants in the conventional disposal process. In this study, a synergetic and high-efficiency treatment of WTCs and PVC by subcritical water (SubCW) process was developed based on the interaction of the two kinds of wastes. The interaction between WTCs and PVC in SubCW could significantly reduce the treatment temperature and shorten the reaction time for recovering high-purity metal tantalum from WTCs, and it could also markedly improve the dechlorination efficiency (DE) of PVC. The optimized conditions for the synergetic treatment of WTCs and PVC were 325 ℃, 30 min, solid-to-liquid ratio of 1:5 g/mL, and PVC-to-WTCs ratio of 6:1 g/g. The resin conversion efficiency (RCE) of WTCs and the DE of PVC could reach 100% and 97.39% under the optimized conditions. The HCl released from PVC in SubCW could significantly promote the acid-catalytic hydrolysis of resin materials in WTCs and resulted in the production of abundant phenol/phenol derivates. In turn, hydroxyl functional group of phenol/phenol derivates could enhance the dechlorination of PVC by promoting the hydroxyl substitution reaction pathway. High level of benzoic acid (72.52%) could be obtained from the interaction between the decomposition products of WTCs and PVC by radical and oxidation reactions. The SubCW synergetic process developed in this study provided a high-efficiency and low-energy strategy for metal tantalum recovery, benzoic acid production, and dechlorination from WTCs and PVC wastes. [Display omitted] [ABSTRACT FROM AUTHOR]