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An endotracheal tube (ETT) is a greatly appreciated medical device at the global level with widespread application in the treatment of respiratory diseases, such as bronchitis and asthma, and in general anesthesia, to provide narcotic gases. Since an important quantitative request for cuffed ETTs was recorded during the COVID-19 pandemic, concerns about infection have risen. The plasticized polyvinyl chloride (PVC) material used to manufacture ETTs favors the attachment of microorganisms from the human biological environment and the migration of plasticizer from the polymer that feeds the microorganisms and promotes the growth of biofilms. This leads to developing infections, which means additional suffering, discomfort for patients, and increased hospital costs. In this work, we propose to modify the surfaces of some samples taken from commercial ETTs in order to develop their hydrophobic character using surface fluorination by a plasma treatment in SF6 discharge and magnetron sputtering physical evaporation from the PTFE target. Samples with surfaces thus modified were subsequently tested using XPS, ATR-FTIR, CA, SEM + EDAX, profilometry, density, Shore A hardness, TGA-DSC, and biological antimicrobial and biocompatibility properties. The obtained results demonstrate a successful increase in the hydrophobic character of the plasticized PVC samples and biocompatibility properties.

The novel work for this study is to make new films for the pure and doped PVC with organosilane; thus, it used organosilane moieties (25 mg) mixed with poly(vinyl chloride) (5 g). Thus drop-casting procedure was utilized to make these thin films. The pure PVC and PVC-organosilane (Si-L-NO 2 /PVC called SI and Si-L-Br called SII) optical properties were studied under the wavelength range from (250 to 1300 nm) using diffusive reflectance equipment. The optical properties like absorption increased up to (87–95%), while reflectance and transmittance decrease when added organosilane molecules. Furthermore, the dielectric constant (real and imaginary) and optical conductivity enhanced, respectively. On the other hand, Urbach energy increases when adding organosilane to PVC structure from 7.7011 to 14.146 eV; furthermore, skin depth, refractive index, and optical density were figured. The energy gap is reduced from 4 to 2.3 eV for the direct transition and from 3.4 to 1.6 eV for the indirect transition. SEM analysis was implemented over thin films of pure PVC and PVC-organosilane to see the morphology of these surfaces. The AFM analysis was utilized to exhibit the topography of the surfaces, thereby finding the surface roughness and the root-mean-square of the surface for these thin films. The improvement for these thin films is used in many applications such as absorption of the light when used as a coating in flat plate collector, and declines the reflectance in radars, strength external applications such as doors, windows, and the dielectric material in electronic devices.

The paper presents the characteristics of unplasticized PVC composites modified with biofiller obtained from the waste eggshells of hen eggs. The composites obtained by extrusion contained from 10 phr to 40 phr of biofiller. The filler was characterized using the SEM, TG, and sieve analysis methods. The influence of the filler on the processing properties was determined using plastographometric and MFR tests. Fundamental analysis of mechanical properties was also performed, i.e., Charpy impact strength and determination of tensile properties. The mechanical properties were supported with dynamical mechanical thermal analysis, time of thermal stability, and thermogravimetric analysis. Structure analysis was also performed using SEM and X-ray microcomputed tomography (micro-CT). The processing properties of the tested composites do not give grounds for disqualifying such material from traditional processing PVC mixtures. Notably, the biofiller significantly improves thermal stability. Ground eggshells (ES) work as scavengers for the Cl radicals released in the first stage, which delays the PVC chain’s decay. Additionally, a significant increase in the value of the modulus of elasticity and softening point (VST) of the composites concerning PVC was found. Ground hen eggshells can be used as an effective filler for PVC composites.

Rigid PVC plastics (R-PVC) contain large amounts of chlorine, and improper disposal can adversely affect the environment. Nevertheless, there is still a lack of sufficient studies on hydrothermal treatment (HTT) for the efficient dechlorination of R-PVC. To investigate the migration mechanism of chlorine during the HTT of R-PVC, R-PVC is treated with HTT at temperatures ranging from 220 °C to 300 °C for 30 min to 90 min. Hydrochar is characterized via Fourier transform infrared spectrometry and X-ray photoelectron spectroscopy. The results revealed that the hydrothermal temperature is the key factor that affects the dechlorination of R-PVC. Dramatic dechlorination occurs at temperatures ranging from 240 °C to 260 °C, and the dechlorination efficiency increases with the increase in the hydrothermal temperature. The main mechanism for the dechlorination of R-PVC involves the nucleophilic substitution of chlorine by -OH. CaCO3 can absorb HCl released by R-PVC and hinder the autocatalytic degradation of R-PVC; hence, the dechlorination behavior of R-PVC is different from that of pure PVC resins. Based on these results, a possible degradation process for R-PVC is proposed. This study suggests that HTT technology can be utilized to convert organochlorines in R-PVC to calcium chloride, achieving the simultaneous dechlorination of R-PVC and utilization of products.

Background/Objectives: Persistent high Premature Ventricular Contraction (PVC) burden (>10%) may result in PVC-induced cardiomyopathy. Current guidelines, supported by limited evidence, recommend flecainide for PVCs originating from the ventricular outflow tract (Class IIa). UNIFLECA is a prospective cohort study, aiming to assess the efficacy and safety of flecainide in PVC burden reduction in adults, irrespective of PVC origin, focusing secondarily on symptom relief and improvement of left ventricular ejection fraction (LVEF) in patients suffering from PVC-induced cardiomyopathy. Methods: Participants were adults with frequent PVCs, defined as PVC burden > 5%, confirmed by two 24 h Holter recordings taken at least one month apart, who denied catheter ablation treatment. Patients who were deemed ineligible for catheter ablation were also included. A total of 50 patients were screened and 35 were administered Flecainide, with dosage adjustment based on follow-up Holter results and QRS increases. Changes in PVC burden, LVEF, symptomatic status, along with treatment adherence, were evaluated. Results: In adults with frequent PVCs, flecainide led to a significant reduction in PVC burden, with a mean decrease of 76.2% in the first month, and 63.1% of patients achieving a PVC burden reduction greater than 80%. Conclusions: UNIFLECA contributes to the understanding of how personalized, non-interventional therapeutic modalities can be employed to manage PVCs, especially for patients unwilling to have or ineligible for ablation procedures.

Polyvinyl chloride (PVC)-dibutyl adipate (DBA) gels are a fascinating dielectric elastomer actuator showing promise in soft robotics. When actuated with high voltages, the gel deforms towards the anode. A recent application of PVC gels in electrohydraulic actuators motivates elastic and hyperelastic constitutive relationships for tensile loading modes. PVC gels with plasticizer-to-polymer weight ratios of 2:1, 4:1, 6:1, and 8:1 w/w were evaluated. PVC gels exhibit a linear elastic region up to 25% strain. The elastic modulus decreased with increasing plasticizer content from 288.8 kPa, 56.1 kPa, 24.7 kPa, to 11 kPa. Poisson’s ratio also decreased with increasing plasticizer content from 0.42, 0.43, 0.39, to 0.35. We suggest that the decrease in polymer concentration facilitates a weakly interconnected polymer network susceptible to chain slippage that hinders the network response, thus lowering Poisson’s ratio. Our work suggests that PVC gels can be treated as isotropic and incompressible for large strains and hyperelastic modeling; however, highly plasticized gels tend to act less incompressible at small strains. The power scaling law between the elastic modulus and plasticizer weight ratio showed high agreement, making the elastic modulus deterministic for any plasticizer content. The Neo–Hookean, Mooney–Rivlin, Yeoh, Gent, Ogden, and extended tube hyperelastic constitutive models are investigated. The Yeoh model shows the highest feasibility when evaluated up to 3.5 stretch, showing a maximum normalized root-mean-square-error of 6.85%. Together, these findings establish a constitutive basis for PVC-DBA gels, incorporating small strain elasticity, large strain non-linear behavior, and network analysis while providing suggestive insight into the network structure required for accurately modeling the EPIC.

Bearing in mind the aspiration of the world economy to create as complete a closed loop of raw materials and energy as possible, it is important to know the individual links in such a system and to systematise the knowledge. Polymer materials, especially poly(vinyl chloride) (PVC), are considered harmful to the environment by a large part of society. The work presents a literature review on mechanical and feedstock recycling. The advantages and disadvantages of various recycling methods and their development perspectives are presented. The general characteristics of PVC are also described. In conclusion, it is stated that there are currently high recycling possibilities for PVC material and that intensive work is underway on the development of feedstock recycling. Based on the literature review, it was found that PVC certainly meets the requirements for materials involved in the circular economy.

This article presents a comparative analysis between the construction system using PVC panels and concrete and conventional masonry, exploring their advantages and disadvantages in the context of civil construction. The main objective is to assess the feasibility of each method, considering factors such as sustainability, cost, efficiency, and environmental impact. The study was conducted based on a literature review of the mechanical properties of PVC, its resistance to degradation, and its practical applications in various areas of construction. Characteristics such as execution speed, durability, and environmental challenges were also compared. The results indicate that the PVC system offers significant advantages in terms of construction speed, resource savings, and durability. However, it presents challenges such as the emission of toxic gases in fire situations and limited suppliers, which can increase costs. Conventional masonry, although widely used and accessible, faces problems such as waste generation and quality control. It is concluded that both systems have their place in civil construction, and the choice between them should be based on a detailed analysis of the project’s needs, considering environmental impacts and long-term costs. Este artículo presenta un análisis comparativo entre el sistema constructivo utilizando paneles de PVC y concreto y la mampostería convencional, explorando sus ventajas y desventajas en el contexto de la construcción civil. El objetivo principal es evaluar la viabilidad de cada método, considerando factores como la sostenibilidad, el costo, la eficiencia y el impacto ambiental. El estudio se llevó a cabo en base a una revisión de la literatura sobre las propiedades mecánicas del PVC, su resistencia a la degradación y sus aplicaciones prácticas en diversas áreas de la construcción. También se compararon características como la velocidad de ejecución, la durabilidad y los desafíos ambientales. Los resultados indican que el sistema de PVC ofrece ventajas significativas en términos de rapidez de construcción, ahorro de recursos y durabilidad. Sin embargo, presenta desafíos como la emisión de gases tóxicos en situaciones de incendio y la limitación de proveedores, lo que puede aumentar los costos. Por otro lado, la mampostería convencional, aunque ampliamente utilizada y accesible, enfrenta problemas como la generación de residuos y el control de calidad. Se concluye que ambos sistemas tienen su lugar en la construcción civil, y la elección entre ellos debe hacerse en base a un análisis detallado de las necesidades del proyecto, considerando los impactos ambientales y los costos a largo plazo.

This study investigated the effect of nanofiller on the structural properties of thermally aged polyvinyl chloride (PVC)/Aluminum oxide (Al2O3) nanocomposites prepared with different amounts of nanoparticles (2.5, 5.0, and 7.5 wt%) using various techniques. Experimental studies were designed to monitor structural changes in PVC/Al2O3 nanocomposites by means of dielectric characterization, charging and discharging currents measurements, SEM and FTIR analyses, and visual observations as a function of nanofiller amount and aging time. The results obtained demonstrated that the dielectric permittivity of PVC was increased for unaged samples with the addition of 2.5% and 7.5% Al2O3 nanoparticles. An increase in dielectric losses is also observed at the same level of filler content, attributable to interfacial polarization driven by improved charge transport and dipole relaxation. A decrease in charging and discharging currents with higher Al2O3 content is attributed to an increase in matrix rigidity, which restricts charge carrier mobility. The charging and discharging currents progressively increased during thermal aging, as polar aging products were formed during this process, which could improve charge mobility and conductivity. FTIR and SEM analyses indicated that with thermal aging, polar groups formation was more likely due to structural decomposition of the matrix and mild dehydrochlorination. The changes in color were indicative of surface degradation. These results provide new insight into the electrical and aging behaviors in PVC/Al2O3 nanocomposites.

In order to assess the human exposure risks from the release of contaminants from water pipes made of polyvinyl chloride (PVC), experiments were carried out by subjecting the PVC pipe material to burning and leaching conditions followed by analysis of the emission and leachate samples. The emissions of burning pipes were analyzed by both infrared spectrometry and gas chromatography-mass spectrometry (GC-MS). The emission test results indicate the presence of chlorinated components including chlorine dioxide, methyl chloride, methylene chloride, allyl chloride, vinyl chloride, ethyl chloride, 1-chlorobutane, tetrachloroethylene, chlorobenzene, and hydrogen chloride were detected in the emissions of burning PVC pipes. Furthermore, the concentrations of benzene, 1,3-butadiene, methyl methacrylate, carbon monoxide, acrolein, and formaldehyde were found at levels capable of affecting human health adversely. The analysis of PVC pipe leachates using GC-MS shows that there are 40–60 tentatively identified compounds, mostly long-chain hydrocarbons such as tetradecane, hexadecane, octadecane, and docosane, were released when the burned PVC materials were soaked in deionized water for one week. Quantitative analysis shows that 2-butoxyethanol, 2-ethyl-1-hexanol, and diethyl phthalate were found in the burned PVC polymer at the average levels of 2.7, 14.0, and 3.1 micrograms per gram (μg/g) of pipe material. This study has significant implications for understanding the benzene contamination of drinking water in the aftermath of wildfires that burned polymer pipes in California.