Polyvinyl Chloride Materials Research Articles

Electrostatic Force Microscopy Measurement System for Micro-topography of Non-conductive Devices

AbstractA home-made electrostatic force microscopy (EFM) system is described which is directed toward assessment of the microscopic geometry of the surface of specimens made of non-conductive material with a large thickness. This system is based on the variation in the electrostatic force between the conductive probe and the non-conductive specimen in order to get its surface morphology. First, based on the principle of dielectric polarization, the variation rules of the electrostatic force between the charged probe and the non-conductive specimen were studied. Later, a special tuning fork resonant probe unit made of quartz crystal was fabricated for measurement of the electrostatic force, and the scanning probe microscopic system in the constant force mode was constructed to characterize the three-dimensional micro-topography of the surface of the specimen. Finally, this system was used to perform scanning measurement experiments on the indented surface of the specimen made of the polyvinyl chloride (PVC) material with thickness 3 mm. In the present experimental system, when the external voltage was 100 V and the distance from the probe tip to the specimen surface approximately 100 nm, the variance in the resonant frequency of the probe unit was around 0.5 Hz. These results indicate that this home-made EFM system can effectively characterize the micro-topography of the non-conductive specimen with very large thickness which is above several millimeters.

Preparation and characterization of polyvinyl chloride based nickel phosphate ion selective membrane and its application for removal of ions through water bodies

Polyvinyl chloride based nickel phosphate (PVC–NP) composite membrane was prepared by cast die method of membrane fabrication. The nickel phosphate (NP) inorganic material has been prepared by the novel sol-gel method which is qualitative method of material synthesis. The composite membrane has been designed by a uniform mixing of the NP and polyvinyl chloride (PVC) materials into 1:3 ratio of percentage. This novel PVC supported NP composite membrane is used as a barrier for transporting the electrolytes and heavy metal ions due their charge characteristic. By this nature composite membrane governs to adsorb and absorb characteristics of cations and anions present in water body. The structural, thermal and electrochemical characterizations were done by using different sophisticated techniques like FTIR, XRD, TGA/DTA as well as SEM-EDX, LCR and potentiometer. The characterizations of material as well as membrane indicated the information of functional groups, material nature, thermal stability, surface structure, porosity, elemental percentages, dielectric nature, ionic transportation etc. Teorell-Meyer-Sievers (TMS) theoretical method is used to determine the charge density of membrane which is an important theory to analyze the performance of designed membrane. The other important parameters of membrane can also be determined very easily by the help of calculated values of membrane charge densities.

Synthesis of SiO 2 @PAA microspheres and their application for controlling diisooctyl terephthalate migration from flexible PVC materials

The preparation of silicon dioxide (SiO2)@poly(acrylic acid) (PAA) microsphere was reported. The modified microspheres can be well dispersed in polyvinyl chloride (PVC) matrix. The structure of SiO2@PAA microspheres can be well-controlled and its mixtures with chlorinated polyethylene (CPE) for controlling diisooctyl terephthalate (DOTP) migration from PVC matrix. The results showed that the migration of DOTP was decreased with increasing content of SiO2@PAA microspheres, and the use of CPE together with SiO2@PAA microspheres has a synergistic effect on the reduction of DOTP migration. Moreover, CPE can enhance the interface combination between SiO2@PAA microsphere and PVC, and good dispersibility was observed in PVC/CPE/SiO2@PAA composites.

Experimental Investigation of the Shear Behavior of EPS Geofoam

Geofoam has been used in a wide range of geotechnical engineering projects since 1960s; either as lightweight fill material (e.g. embankments and bridge approaches) or as compressible inclusion (e.g. retaining walls and culverts). In most of these projects, geofoam is installed either in direct contact with other geofoam blocks or other construction material. Successful design of these composite systems requires a good understanding of both the compression and shear behavior of the geofoam blocks as well as the shear strength of the interface. In this study, an attempt has been made to measure the shear strength parameters of expanded polystyrene (EPS) geofoam blocks of different densities as well as the interface strength parameters as these blocks interact with sand as well as polyvinyl chloride (PVC) material. A series of direct shear tests has been carried out on geofoam samples of three different densities, namely, 15, 22 and 35 kg/m3. Shear test results on geofoam monoblocks showed that the increase in density results in an increase in the material cohesion, which is associated with a decrease in the internal friction angle. Most of the interface resistance was found to develop at small displacements. For geofoam–PVC interface, both the adhesion and angle of interface friction slightly increased with the increase in geofoam density. The measured geofoam–sand interface strength revealed a consistent increase in the angle of interface friction as the density of geofoam material increased. These experimental results can be used to guide engineers in estimating the interface parameters needed for both analytical and numerical analyses involving soil–EPS–structure interaction.

Synthesis, Characterization, Electrochemical and Antibacterial Studies of Synthesized PVC Supported CP Composite

The copper phosphate {Co3 (PO4 )2 } inorganic material has been synthesized by the sol gel method. The PVC supported CP membrane was designed by the mixing of inorganic CP and organic polyvinyl chloride (PVC) materials in 1:3 ratios of percentage. This membrane is used as a barrier for transportation of electrolyte and heavy metal ions due the charged particles on it. Due to this nature of membrane, it governs to adsorb as well as absorb characteristics of cations and anions. The structural, thermal and electrochemical characterizations were done by using different sophisticated techniques like FTIR, XRD, TGA/DTA as well as SEM-EDX, LCR and potentiometer analysis. The characterizations of material and membrane indicated the information of functional groups, material nature, thermal stability, surface structure, porosity, elemental percentages, dielectric nature, ionic transportation etc. Teorell-Meyer-Sievers (TMS) theoretical method is used to determine the charge density of membrane which is an important theory is used to analyze the performance of membrane. The other important parameters of membrane have also been determined easily by the help of obtained values of charge densities.

Устойчивость в агрессивных средах поливинилхлоридных материалов, модифицированных активированным волластонитом

Устойчивость в агрессивных средах поливинилхлоридных материалов, модифицированных активированным волластонитом

Materials of Construction Test: Insuring the Use of Safe Materials in Photo Books

The photographic industry has had a long-standing concern over the use of materials containing poly vinyl chloride (PVC) materials. This caution was warranted due to PVC materials and plasticizers causing damage to silver halide photographic prints in the 1970s and early 1980s, often from album covers and print storage sleeves, among others. Several international standards for safe storage of photographic materials specifically forbid the use of PVC-containing materials. However, as the photo book industry has grown, new imaging materials are now in use, such as pages produced with electrophotographic printing technologies. In addition the actual materials used in construction of the photo book itself have changed, including the use of modern PVC-containing materials. Given the historical concerns around the use of PVC, an extensive test was designed to explore a range of modern PVC-containing materials in combination with the typical range of imaging media in use today. This includes silver halide, electrophotographic, inkjet, and thermal dye transfer imaging systems. This paper will review the design, implementation, and results of this test, as well as provide recommendations and test procedures that can be used to determine the compatibility of photo book construction materials with various imaging systems.

Effect of chlorine treatment on inhibition of E. coli serogroup O2 incorporation into 7-day-old biofilm on polyvinylchloride surface

Poultry waterlines are constructed using polyvinylchloride (PVC) material on which bacterial biofilm can easily form. Biofilm can harbor pathogens including avian pathogenic E. coli (APEC) strains. An in vitro evaluation was performed to determine if E. coli sero group O2 (avian pathogenic) could attach on a PVC surface that had pre-formed biofilm and if this phenomenon could be affected when water was treated with chlorine. Initially, biofilm growth was induced in PVC test coupons (15.16 cm2) for a 7-day period mimicking the waterline scenario in the first wk of poultry brooding; and then this biofilm was challenged with E. coli O2 seeded water in presence/absence of chlorine treatment. After rinsing, test coupons were sampled for bacterial (APC) and E. coli O2 enumeration at various occasions post seeding the pathogen and chlorine treatment. Day 7 APC recovered from coupons was 4.35 log10 cfu/cm2 in trial 1 and 3.66 log10 cfu/cm2 in trial 2. E. coli O2 was not recovered from chlorine treated test coupons (P <0.05), whereas it was retrieved from untreated coupons (untreated contained >3 log10 cfu/cm2 in trial 1 and >2 log10 cfu/cm2 in trial 2). This study suggests that E. coli O2 can incorporate into pre-formed biofilm on a PVC surface within 24 h if water sanitation is not present, and the attachment time of the pathogen can prolong in the absence of already formed biofilm.

Effect of 2% chlorhexidine treated coronal dentin on bond strength of two self-adhesives cements

Despite advances in adhesive dentistry, lasting bonds between indirect restorations and dentin remain a challenge. Objective: Therefore, the aim of this study was to evaluate the effect of chlorhexidine on the bond strength of self-adhesive cements to dentin after storage for 24 h and 90 days. Material and methods: Forty-eight human third molars crowns were included in polyvinyl chloride matrices using acrylic resin and worn to expose a flat dentin area. The specimens were randomly distributed into 8 groups (n = 12) in accordance with the self-adhesive cement (Rely X U200 and Smart Cem 2), the dentin treatment (application or not of 2 % chlorhexidine digluconate solution for 1 min) and the storage period (24 h or 90 d). Two cylinders’ cements (1.4 x 1 mm) were constructed on the dentin surfaces of each sample, stored in distilled water for 24 h or 90 days and submitted to a micro-shear test. Subsequently, a failure analysis was performed to classify the failure into adhesive, cohesive, and mixed. Data were subjected to ANOVA and Tukey (0.05) tests. Results: There was a statistically significant difference between the materials (Rely X U200 > Smart Cem 2 – p < 0.05) regardless of the surface treatment and the storage period. Conclusion: The chlorhexidine application did not affect the immediate or delayed bond strength values, regardless of the self-adhesive cement.

Preparation, characterization and application of GO-TiO2/PVC mixed matrix membranes for improvement in performance

Abstract Poly vinyl chloride (PVC) membranes are known for their low cost as well as good mechanical, thermal and chemical stability. However, the inherent hydrophobicity of the PVC material leads to fouling of membrane. Thus, in this paper, we have attempted to use GO-TiO2 nanosheets-blended PVC membranes. GO-TiO2 nanosheets are blended in the casting solution containing PVC and polyvinylpyrrolidone (PVP). Filtration experiments show that blending of GO-TiO2 sheets enhanced the permeate flux while keeping the rejection of humic acid almost same. The results are supported by characterizations like SEM, EDX, TEM, AFM, XRD and contact angle measurements.

Up regulation of IL-6 is involved in di (2-ethylhexyl) phthalate (DEHP) induced migration and invasion of non small cell lung cancer (NSCLC) cells.

Di (2-ethylhexyl) phthalate (DEHP), which is widely used in polyvinyl chloride materials, can be easily accumulated into human body. Lung cancer cells can be directly exposed to DEHP via inhalation, however, the effects and related mechanisms of DEHP on the progression of non small cell lung cancer (NSCLC) were not illustrated. Our present study revealed that DEHP less than 10-4M had no significant effect on the proliferation of A549 or H1299 cells, while nanomolar DEHP can trigger the migration and invasion of NSCLC cells. DEHP treatment also increased the expression of interleukin-6 (IL-6) and IL-8. Silencing of IL-6, while not IL-8, can attenuate DEHP induced migration and invasion of NSCLC cells. This was confirmed by result that neutralization antibody of IL-6, while not anti-IL-8, attenuated DEHP induced invasion of A549 cells. The inhibitor of NF-κB, while not ERK1/2 or Akt, abolished DEHP induced up regulation of IL-6 and invasion of NSCLC cells. DEHP treatment can increase the phosphorylation, nuclear localization, and transcriptional activities of p65, one of the major parts of NF-κB complex. Collectively, our study revealed that DEHP can stimulate NSCLC migration and invasion via NF-κB mediated up regulation of IL-6.

Influence of Decontaminating Agents and Swipe Materials on Laboratory Simulated Working Surfaces Wet Spilled with Sodium Pertechnetate.

Context:Decontamination of various working surfaces with sodium pertechnetate minor spillage is essential for maintaining good radiation safety practices as well as for regulatory compliance.Aim:To observe the influences of decontaminating agents and swipe materials on different type of surfaces used in nuclear medicine laboratory work area wet spilled with 99m-technetium (99mTc) sodium pertechnetate.Settings and Design:Lab-simulated working surface materials. Experimental study design.Materials and Methods:Direct decontamination method on dust-free lab simulated new working surfaces [stainless steel, polyvinyl chloride (PVC), Perspex, resin] using four decontaminating agents [tap water, soap water (SW), Radiacwash, and spirit] with four different swipe material [cotton, tissue paper (TP), Whatman paper (WP), adsorbent sheet (AS)] was taken 10 samples (n = 10) for each group.Statistical Analysis:Parametric test two-way analysis of variance is used with significance level of 0.005, was used to evaluate statistical differences between different group of decontaminating agent and swipe material, and the results are expressed in mean ± SD.Results:Decontamination factor is calculated after five cleaning for each group. A total of 160 samples result calculated using four decontaminating agent (tap water, SW, Radiacwash, and spirit), four swipe material (cotton, TP, WP, and AS) for commonly used surface (stainless steel, PVC, Perspex, resin) using direct method by 10 samples (n = 10) for each group.Conclusions:Tap water is the best decontaminating agent compared with SW, Radiac wash and spirit for the laboratory simulated stainless steel, PVC, and Perspex surface material, whereas in case of resin surface material, SW decontaminating agent is showing better effectiveness. Cotton is the best swipe material compared to WP-1, AS and TP for the stainless steel, PVC, Perspex, and resin laboratory simulated surface materials. Perspex and stainless steel are the most suitable and recommended laboratory surface material compared to PVC and resin in nuclear medicine. Radiacwash may show better result for 99mTc labelled product and other radionuclide contamination on the laboratory working surface area.

Thermo-mechanical characterization of banana particulate reinforced PVC composite as piping material

A banana particulate reinforced polyvinyl chloride (PVC) composite was developed with low cost materials having an overall light-weight and good mechanical properties. The specimen composite material was produced with the banana (stem) particulate as reinforcement using compression molding. The composition with optimum mechanical property of 42MPa was estimated to have a long term stress value of 25MPa corresponding to 40% loss in strength over a period of 32years. This composition has a formulation of 8%, 72% and 20% of banana stem particulates (reinforcement), PVC (matrix) and Kankara clay (filler) respectively with corresponding water absorption of 0.79%, Young’s Modulus of 1.3GPa and a density of 1.24g/cm3. Thermogravimetric analyses showed that constituents of reinforcement/filler in the composite increased the thermal stability of the composite by 38.6% over that of pure PVC. The composite has better creep stability at elevated temperatures than PVC. Long term TTS (time–temperature-superposition) performance prediction at 50°C showed the composite satisfied WLF assumption with reduced stiffness to 0.65GPa over an estimated period in excess of 100years of usage indicating better long term performance than PVC pipe material – the stiffness could be much higher when used below 50°C. Comparison with conventional piping materials showed the composite offered a price savings per meter length of 84% and 42% when compared with carbon steel and PVC material.

Influence of Fillers on Polyvinyl Chloride Materials Thermal Resistance

Innovative materials and structures are analyzed in this paper. Multicomponent formulation of polyvinyl chloride materials containing various functional additives requires assessment of their influence on polymer stability while processing and operating. According to the nature, particulate fillers widely used in plasticized and liquid compositions based on polyvinyl chloride may have different impact on thermal resistance of materials. This paper presents the study of organic and nonorganic dispersed waist as filler in polyvinyl chloride formulation and determines key parameters of their influence on thermal resistance of composition. Polyvinyl chloride stabilization course by means of polyfunctional fillers-modifiers in different mechanisms, such as: chemical stabilization – chloride hydride acceptance, replacement of chlorine labile atom in polymer macromolecule, adjoining conjugated defective ethylenic bonds, recombination macroradicals and physical stabilization – chloride hydride sorbing, reduction of mechanical destruction by oiling, etc. have been considered. Contribution into stabilization course in various mechanisms depending on chemical nature, dispersion rate and mineral content of fillers is evaluated.

An investigation on 4-aminobenzoic acid modified polyvinyl chloride/graphene oxide and PVC/graphene oxide based nanocomposite membranes

We synthesized graphene oxide (GO) using a modified Hummer’s method, and then blended it into polyvinyl chloride (PVC) and amino-functional PVC (PVC-4ABA) matrices. GO was added to 0.5 g PVC at 0.01, 0.05, 0.1 and 0.5 g. The PVC/GO matrix was modified using 4-aminobenzoic acid (4ABA) at 0.01, 0.05, 0.1 and 0.5 g per 0.5 g PVC. This gave four amino-functional PVC/GO series and one PVC/GO series nanocomposite membranes that were prepared by a solution blending route. The filler and the modifier (4ABA) content effect on the PVC membrane properties were investigated. Fourier transform infrared spectroscopy confirmed the GO functional groups and PVC modification with 4ABA. According to scanning electron microscopy, a unique two-way layered structure was observed for modified PVC and GO composites. XRD explained the conformation of PVC/GO and modified PVC/GO nanocomposites. GO crystallite size and its interlayer distance between sheets were also studied. The XRD peak at 2θ = 10.8° with interlayer spacing of 0.81 nm was calculated with the Bragg equation. GO particle size was calculated (Scherrer formula) as 7.78 nm. XRD results revealed fine interaction between modified PVC and GO compared with unmodified PVC composites. Glass transition temperature (Tg) of non-modified PVC/GO nanocomposite was 202℃, whereas modified nanocomposite with similar GO loading had Tg equal to 212℃. Higher filler content gave better hydrophilic membranes as determined by solvent content, porosity, and shrinkage ratio. PVC-4ABA-0.5/GO 0.5 membrane with a low contact angle (25°) is a fine option for water purification. The overall results suggest that the higher modifier concentrations developed better interaction between the nanofiller and PVC.

Effect of Machined Surface Shape on Sound Reflection

Sound reflection of materials is influenced by many factors, e.g. by material type, density, thickness, porosity, angle of sound incidence, surface shape and excitation frequency of acoustic wave. The aim of the paper is to investigate the surface shape effect of expanded polyvinylchloride material on sound reflection. For this reason polyvinylchloride samples of different surface shapes and perforations were produced on universal and CNC machine tool. The material ability to reflect sound of the investigated polyvinylchloride samples was experimentally measured by means of the transfer function method on Kundt's impedance tube. The material samples were subsequently compared in terms of their sound reflection. It was verified that the highest sound reflection was obtained in case of the smooth surface polyvinylchloride sample.

Bis-(2-ethylhexyl) Phthalate Increases Insulin Expression and Lipid Levels in Drosophila melanogaster.

Bis-(2-ethylhexyl) phthalate (DEHP) is one of the most widely used plasticizers, and human beings are exposed to DEHP via polyvinyl chloride (PVC) materials, medical equipment and even drinking water. While DEHP has been implicated to influence metabolism and endocrine functions, important questions remain about the molecular mechanisms of these effects. We employed the model organism Drosophila melanogaster and examined physiological, molecular and behavioural effects from DEHP-contaminated food. We found that DEHP, at levels comparable to human exposure, made male flies more resistant to starvation and increased lipid levels, while decreasing circulating carbohydrates. Moreover, DEHP-fed male flies had higher expression levels of an insulin-like peptide known to regulate metabolism, as well as the insulin receptor. Our results suggest that long-term DEHP feeding may induce diabetes-like dysfunctions. These findings provide a molecular background of how DEHP may have detrimental effects on metabolic functions.

The application of prepared porous carbon materials: Effect of different components on the heavy metal adsorption.

In this study, five typical municipal solid waste (MSW) components (tyres, cardboard, polyvinyl chloride (PVC), acrylic textile, toilet paper) were used as raw materials to prepare four kinds of MSW-based carbon materials (paperboard-based carbon materials (AC1); the tyres and paperboard-based carbon materials (AC2); the tyres, paperboard and PVC-based carbon materials (AC3); the tyres, paperboard, toilet paper, PVC and acrylic textile-based carbon materials (AC4)) by the KOH activation method. The characteristic results illustrate that the prepared carbon adsorbents exhibited a large pore volume, high surface area and sufficient oxygen functional groups. Furthermore, the application of AC1, AC2, AC3, AC4 on different heavy metal (Cu(2+), Zn(2+), Pb(2+), Cr(3+)) removals was explored to investigate their adsorption properties. The effects of reaction time, pH, temperature and adsorbent dosage on the adsorption capability of heavy metals were investigated. Comparisons of heavy metal adsorption on carbon of different components were carried out. Among the four samples, AC1 exhibits the highest adsorption capacity for Cu(2+); the highest adsorption capacities of Pb(2+) and Zn(2+) are obtained for AC2; that of Cr(3+) are obtained for AC4. In addition, the carbon materials exhibit better adsorption capability of Cu(2+) and Pb(2+) than the other two kind of metal ions (Zn(2+) and Cr(3+)).

Numerical investigation of generalized Graetz problem in circular tube with a mass transfer coupling between the solid and the liquid

The unsteady diffusion equation in a tube and the advection/diffusion equation in laminar flow in a liquid of a solute are theoretically established. The most important parameters are the migration strength α and the so-called Graetz number Gr. The former dimensionless number is the product of the partition coefficient of the solute at the solid/liquid interface, the ratio of the tube thickness to the interior radius and the ratio of diffusion coefficients of the solute in the liquid and in the solid. The Graetz number Gr is the ratio of the diffusion time scale in the liquid based on the interior radius of the pipe to the advection time over the tube length. The problem is applied to the plasticizer migration from a polyvinyl chloride material to a liquid with the safety food applications in mind. The migration of the plasticizer is solved numerically for various tube sizes, flow conditions and partition coefficients of the plasticizer in the liquid. For comparison, the numerical results obtained in static condition are also provided.The average plasticizer concentration in the liquid behaves following two main regimes as a function of the migration strength. When α is much smaller than one, the average plasticizer concentration in the liquid is an algebraic function of the axial coordinate, z, at the power two third and increases linearly with time. Conversely, when α is much larger than one, the average plasticizer concentration is linear as a function of axial distance and increases as a function of the square root of time. Moreover, the concentration is much smaller of few orders of magnitude in dynamic condition than in static working showing that in the context of food contamination the dynamic approach is more appropriate and relevant for demonstration of compliance with the safety authorities requirements.

Treatment of Snoring with a Nasopharyngeal Airway Tube

Objective. To study the feasibility of a standard nasopharyngeal airway tube (NPAT) as treatment for snoring. Methods. An obese 35-year-old man, who is a chronic, heroic snorer, used NPATs while (1) the patient's bedpartner scored the snoring and (2) the patient recorded himself with the smartphone snoring app “Quit Snoring.” Baseline snoring was 8–10/10 (10 = snoring that could be heard through a closed door and interrupted the bedpartner's sleep to the point where they would sometimes have to sleep separately) and 60–200 snores/hr. Several standard NPATs were tested, consisting of soft polyvinyl chloride material raging between 24- and 36-French (Fr) tubes. Results. The 24 Fr tube did not abate snoring. The 26 Fr tube was able to abate the snoring sound most of the night (smartphone app: 11.4 snores/hr, bedpartner VAS = 2/10). The 28 and 30 Fr tubes abated the snoring sound the entire time worn (smartphone app: 0 snores, bedpartner VAS 0/10) but could not be tolerated more than 2.5 hours. The tube of 36 Fr size could not be inserted, despite several attempts bilaterally. Conclusion. Appropriately sized nasopharyngeal airway tubes may abate the snoring sound; however, as in this patient, they may be too painful and intolerable for daily use.