Chloride Blends Research Articles

Efficacious constrained layer damping of carbon black‐reinforced nitrile butadiene rubber‐polyvinyl chloride blend vulcanizates: A comprehensive study

AbstractWe report efficacious vibration damping of carbon black reinforced nitrile butadiene rubber‐polyvinyl chloride blend (NVC) vulcanizates in a constrained layer damping (CLD) configuration. The objective is to compare numerical simulations using finite element method (FEM) and the widely used Ross‐Kerwin‐Ungar (RKU) model with the experimental results. NVC blend (50:50 by weight), was compounded with carbon black as reinforcing filler and vulcanized using a sulfur‐based curative system. Significant reinforcement and toughening were observed for the carbon black reinforced vulcanizates compared to the pristine blend. The viscoelastic properties of the vulcanizates were assessed using dynamic mechanical analysis (DMA), exploring their behavior concerning temperature variations and different frequencies to generate the Prony series coefficients for input in FEM analysis. Vibration damping experiments were conducted using the Oberst beam method in a single cantilever mode, with steel as the vibrating substrate, aluminum as the constraining layer, and the NVC vulcanizates as viscoelastic materials (VEM). Numerical simulations were performed using FEM to analyze mode shapes and frequency response function (FRF), and the RKU model was employed to quantify CLD system loss factors (SLF). The salient finding of this study was the observed SLF values in the range of 0.08–0.20 in the frequency regime of 200–2000 Hz. These values qualify the studied material as effective VEMs for CLD treatment of structural vibrations. This study supports design optimization efforts in a wide range of engineering applications where effective vibration damping is critical.Highlights Enhancement of NVC blend properties through carbon black reinforcement. Detailed analysis of viscoelastic behavior using DMA. Validation of findings through experimental modal analysis. Promising results in terms of system loss factors for CLD applications.

Understanding leaching of amylopectin from cellulose/amylopectin/[Bmim][Cl] blends during regeneration from water and aqueous ethanol using molecular dynamic simulations

The difference in amylopectin leaching from cellulose/amylopectin/1-butyl-3-methylimidazolium chloride ([Bmim][Cl]) blends during regeneration in water and aqueous ethanol has been observed in experimental studies. To fully understand the above phenomenon, molecular dynamic simulation was adopted to illustrate the regeneration mechanism after dissolution to understand interactions responsible for the elution/leaching of amylopectin starch. Molecular dynamics (MD) simulations reveal that amylopectin dissolution in [Bmim][Cl] is similar to cellulose in ionic liquids (ILs). Strong hydroxyl-Cl- hydrogen bonding drives dissolution, with [Bmim]+ ions playing a stabilizing role through van der Waals interactions. Amylopectin regeneration in water and aqueous ethanol occurs through the initial disruption of weak hydroxyl-Cl- bridging bonds followed by the disruption of strong non-bridging hydrogen bonds. The water network intercalates amylopectin chains, forming a few “short-lived” interchain HBs. This leaves a very weak electrostatic interaction as the dominant intermolecular interaction between water-regenerated amylopectin chains. Water solvates and elutes low molecular weight amylopectin oligomers, with only 47.29 % amylopectin retained in the blend. In contrast, ethanol-water hydrophobic-hydrogen interactions disrupt the water network, create an ethanol-rich environment, shorten the intermolecular distance between chains, decrease diffusivity, increase hydrogen bonding lifetime between amylopectin, and regenerate amylopectin in aqueous ethanol. The regenerated amylopectin chains interact through improved but weak electrostatic interaction. Improved interaction between chains limits the erosion of low-molecular-weight amylopectin from films retaining 83.11 % amylopectin, approximately two times that in water. At a molecular level, we established that a very weak electrostatic interaction among amylopectin is responsible for leaching in water during regeneration. Ethanol enhances electrostatic interaction among amylopectin chains to limit amylopectin leaching in aqueous ethanol. These observations could apply to other polysaccharide blended materials prepared by the dissolution-regeneration method.

Novel polyvinyl chloride ultrafiltration membranes blended with amphiphilic polyethylene glycol-block-poly(1, 2-dichloroethylene) copolymer for oily wastewater treatment

Amphiphilic di-block copolymer consisting of polyethylene glycol (PEG) and poly(1,2-dichloroethylene) (PDCE) blocks was synthesized following the atom transfer radical polymerization (ATRP) procedure. The chemical structure of the obtained di-block copolymer PEG-b-PDCE was confirmed by different characterization techniques. Polyvinyl chloride (PVC) blend PEG-b-PDCE ultrafiltration (UF) membranes (PVC/PEG-b-PDCE) were prepared using the non-solvent induced phase separation (NIPS) technique and their characteristics were investigated as a function of the PEG-b-PDCE blending ratio in the casting solution. Water contact angle, permeate flux, and oil–water emulsion separation tests were performed to evaluate the hydrophilic character, permeability and anti-fouling membrane performance. It was found that the presence of PEG-b-PDCE copolymer affected the morphological structure of the membrane showing its good pore-forming capability. The oil rejection ability and anti-fouling properties of the blend membranes were improved by increasing the PEG-b-PDCE content up to 0.075 wt%. Compared to PVC membrane, the blend membrane prepared with 0.075 wt% PEG-b-PDCE exhibited about four times higher permeability with an excellent oil rejection factor, 98.78 %, indicating that the PVC/PEG-b-PDCE blend membranes have high potential in oily wastewater treatment.

Phase-Separated Structure of NBR/PVC Blends with Different Acrylonitrile Contents Investigated Using STEM-EDS Mapping Analysis.

We investigated the phase-separated structure of nitrile butadiene rubber (NBR)/polyvinyl chloride (PVC) blends with different acrylonitrile (AN) contents in the NBR, using dynamic mechanical analysis measurements and scanning-transmission-electron-microscopy (STEM)-energy-dispersive-X-ray-spectroscopy (EDS) elemental analysis. Two separate sharp tan δ peaks were observed in the blend at the lower AN content of 18.0%, whereas a broad peak was observed in the blends with the higher AN contents of 29.0 and 33.5%, due to the increase in miscibility, as expected from the decrease in the solubility parameter difference with the increasing AN content. The STEM-EDS elemental analysis for the concentration distribution showed that the NBR was mixed in the large PVC domains with a diameter of several micrometers, and the excluded PVC existed around the interface of the domain-matrix phases in the blend with the lower AN content, whereas small domains with a diameter of several tens of nanometers were dispersed in the blend with the higher AN content. The concentration difference in PVC between the PVC domain and the NBR matrix became smaller with increasing miscibility as the AN content increased although the blends contained the same PVC content of 40 wt%.

A study on nitrile rubber/polyvinyl chloride blend vulcanization kinetics with different fillers by using single isothermal rheograph

An attempt has been made to establish a reasonably accurate microkinetics model for accelerated sulfur vulcanization of commonly used acrylonitrile rubber/polyvinyl chloride (NBR/PVC 70/30) blend (NVC73) from a single, isothermal rheograph data of torque versus time. The effect of three different types of fillers, such as pre-exfoliated organically modified montmorillonite (OMMT) clay, graphite (GRT) powder, and high abrasion furnace (HAF) carbon black (CB), were studied. The kinetics study was done with six solid-state reaction kinetics models. Among these, Sestak-Berggren (SB) equation was found to be the best model for the present compositions. The SB kinetic rate expressions were evolved after several iterations using empirical values of autocatalytic and non-autocatalytic orders of ‘ m’ and ‘ n’, respectively. The gum vulcanizate and OMMT clay-loaded compositions were found to have comparable conversion function f (α) and almost identical reaction rate constants at 150°C, under isothermal conditions. In comparison, HAF CB and GRT rate expressions differed from clay-loaded compositions. The validity of the reaction rate equations obtained was confirmed by comparison of plots for experimental and derived conversions with time.

The effects of surface modified date‐palm fiber fillers upon the thermo‐physical performances of high density polyethylene‐polyvinyl chloride blend with maleic anhydride as a grafting agent

AbstractTo demonstrate the upcycling of thermoplastic waste with good thermo‐physical properties, high density polyethylene (HDPE; 80 phr) and polyvinyl chloride (PVC; 20 phr) are mixed as the matrix using maleic anhydride (MAH) reinforced with unmodified and modified date palm fibers (DPFs; 30 phr). The effects of in situ grafting of MAH onto the DPFs‐HDPE‐PVC composites upon the resultant thermo‐physical characteristics are investigated and analyzed via Fourier transform infrared spectroscopy and scanning electron microscopy. Thus, the effective compatibilizing of both the HDPE‐PVC component and the grafted HDPE‐PVC blend with the modified DPFs are confirmed. In addition, the results of dynamical mechanical analysis and differential scanning calorimetry indicate that the glass transition temperature (Tg) of the composite is enhanced by the incorporation of modified DPFs. The thermal, mechanical, and water uptake properties of the composites are also improved. Rheological analysis at low frequency reveals that the introduction of hydrolyzed DPFs results in a higher complex viscosity (1.94 × 106 Pa s) and storage modulus (119,844 MPa) for the obtained composite (designated G‐Hydro). Overall, the G‐Hydro composite exhibits the best performance, making it ideal for a variety of construction and building purposes.

MWCNT nanocomposite films prepared using different ratios of PVC/PCL: Combined FT-IR/DFT, thermal and shape memory properties

Multi-wall carbon nanotube (MWCNT) mechanically strengthens the polymer and increases heat transfer within polymers as it increases its electrical properties. In this study, composites were produced by doping with poly ɛ-caprolactone (PCL) / poly vinyl chloride (PVC) blend prepared at different ratios, with a fixed MWCNTs ratio of 0.1%. By doing this, it is aimed to examine the effect of polymers, which are blend components, for the MWCNT polymer blend composite. It has been observed that all of the composites have shape-memory effects. When the thermal properties of the MWCNT blend composite were examined, it was observed that the melting temperature increased with increasing PCL ratio, in addition, two-step mass loss occurred in all composites. From the opacity measurements, it was seen that the transparency increased as the PVC ratio increased. Additionally, it was determined that the peaks overlapped when the density functional theory (DFT) and experimentally derived Fourier Transform Infrared spectroscopy (FTIR) spectra were compared.

Opening tubular structure polyimide/polyvinyl chloride based carbon nanofibers for supercapacitor

Polyimide (PI) and polyvinyl chloride (PVC) blend electrospun fibers are prepared by electrospinning process. PI/PVC electrospun fibers exhibit a certain degree of phase separation due to the incomplete compatibility of PI and PVC in N, N’-dimethylformamide. PI/PVC based carbon nanofibers with opening tubular structure can be obtained via thermally induced phase separation. The effect of precursor composition on the morphology and pore structure of carbon nanofibers is investigated by theoretical calculation and structural analysis. The relationship between pore structure and electrochemical performance of carbon nanofibers is studied significantly. Opening tubular structure carbon nanofibers derived from PI: PVC (mass ratio = 1: 1) electrospun fibers show suitable average pore diameter (5.12 nm), high BET specific surface area (1127.1 m2∙g−1) and large total pore capacity (0.65 cm3∙g−1). And opening tubular structure carbon fibers as electrodes in ionic liquid electrolyte exhibits a wide electrochemical stability window (3.5 V), high energy density (30.1 Wh∙kg−1), good power density (2685.5 W∙kg−1) and low internal resistance (2.1 Ω).

Pengaruh nilai K-value dan Penambahan Filler terhadap Kualitas Kulit Sintetis berbasis Polivinil Klorida

Synthetic leather is generally made using polyvinyl chloride or polyurethane resins by coating method. The balance between quality and production costs of the final product is influenced by the selection of the right material composition. Polyvinyl chloride resins are available in a variety of k-values, while fillers are often added to modify mechanical characteristics and lower the costs. The aim of this study was to examine the effect of the k-value of polyvinyl chloride blend and the amount of filler on the quality of synthetic leather. Plastisol is prepared by mixing resin, primary plasticizer, secondary plasticizer, and stabilizer according to the formulation. PVC resin blend with different k-values and certain amount of filler (10, 20, 30 and 40 phr) were used. The quality of the samples was tested using adhesion strength, tensile strength, and elongation at break testing according to ASTM D751-06. The results showed that resins blend with different k-values could be used to obtain the desired quality. The value of the adhesion strength, tensile strength and elongation at break will approach the characteristics of the larger part of the resin. The homogeneity of plastisol because of resin blend also needs attention, especially if the k-value difference between two resin is too large. Meanwhile, the use of calcium carbonate as filler in general will reduce the test results obtained.

Structural, conductivity, mechanical and wettability properties of copper alumina reinforced chlorinated polyethylene/polyvinyl chloride blend nanocomposites

Structural, conductivity, mechanical and wettability properties of copper alumina reinforced chlorinated polyethylene/polyvinyl chloride blend nanocomposites

Thermal degradation kinetics, mechanism, thermodynamics, shape memory properties and artificial neural network application study of polycaprolactone (PCL)/polyvinyl chloride (PVC) blends

Thermal degradation kinetics, mechanism, thermodynamics, shape memory properties and artificial neural network application study of polycaprolactone (PCL)/polyvinyl chloride (PVC) blends

Physico-Chemical Structure and Gasification Performance of Co-Pyrolytic Char Produced by the Pyrolysis of Polyvinyl Chloride Blends with Two Rank Coals.

Co-pyrolysis of waste plastics and coal has been considered to be an environmentally friendly and scalable waste treatment technology. This study investigated the influence of polyvinyl chloride (PVC) on the physico-chemical structure and gasification performance of co-pyrolytic char with lignite (PZ) and bituminous (SM) coal. The structure characteristics were explored by applying an X-ray diffractometer and a specific surface area analyzer. The quantitative analysis on the influence of PVC on pore characteristics and carbon microcrystal structure was conducted by the fractal theory and deconvolution method. The gasification performance was explored using a thermogravimetric analyzer. When the PZ blending ratio was larger than 50%, the specific surface area of PVCPZ chars enlarged significantly due to the increment of mesopores. Nevertheless, the effect of SM on the pore structure was not pronounced, and the specific surface area of PVCSM chars was as small as PVC char. A higher PZ blending ratio benefited the formation of mesopores with an aperture smaller than 10 nm for PVCPZ chars, whereas SM had little influence on pore diameter distributions of PVCSM chars attributed to the remarkable coating effects. The values of fractal dimension of co-pyrolytic char were larger than PVC char, revealing that the adjunction of coal increased the pore surface coarseness and improved the complicacy of the pore structure. Quantitative analysis on XRD spectra indicated that the disorder extent of the carbon structure was improved because of coal addition, and the influence of lignite on the disorder degree of the carbon structure was more significant. The gasification reaction of co-pyrolytic char showed significant synergistic effects, resulting in the improvement of gasification performance.

Effect of nanoclay reinforcing filler in nitrile rubber/polyvinyl chloride blend: frequency response of dynamic viscoelasticity and vibration damping

Effect of nanoclay reinforcing filler in nitrile rubber/polyvinyl chloride blend: frequency response of dynamic viscoelasticity and vibration damping

Structural, Optical, Mechanical and Antibacterial Properties of MgO/Poly(Vinyl Acetate)/Poly(Vinyl Chloride) Nanocomposites

Polymeric blends and nanocomposites with improved functional properties have attracted attention worldwide for industrial applications. For food packaging applications and carrying purposes, the materials to be used should have UV blocking ability, antibacterial activity, and good mechanical properties. In this study, polyvinyl acetate (PVAc)/polyvinyl chloride (PVC) blends with optimized properties and MgO/PVAc/PVC polymer nanocomposites (PNCs) were prepared by solution casting and evaporation. Fourier transform infrared (FTIR) spectroscopy confirmed the complexation and miscibility between PVAc and PVC and their interaction with MgO nanoparticles (NP). X-ray diffraction and HR-TEM analyses showed the phase purity of MgO NP with a crystallite size of ~ 18.8 nm and their dispersion in the amorphous regions of the blend without affecting the structure of each other. UV–vis-NIR spectroscopy revealed that the band gap of the blend can be tuned by changing the added ratio of each polymer, and loading MgO NP increased the semiconducting behavior of the blend. Various optical constants such as the refractive index, absorption index, and optical dispersion parameters have been evaluated. The blend composition and effects of MgO content on the stress–strain behavior were studied. The addition of MgO to the blend enhanced the tensile modulus and strength. However, there was a corresponding decline in toughness and elongation at break. These results reflect the reinforcing effect of MgO NP, which reduces the flexibility of the polymer chains. The antibacterial activities of MgO/PVAc/PVC PNCs against Staphylococcus aureus, Escherichia coli, and Candida albicans fungi are studied. The improvements in optical, mechanical, and anitmicrobial properties make these nanocomposites suitable for some optical devices and in food packaging applications.

The effect of graphene and nanoclay on properties of nitrile rubber/polyvinyl chloride blend with a potential approach in shock and vibration damping applications

The effect of graphene and nanoclay on properties of nitrile rubber/polyvinyl chloride blend with a potential approach in shock and vibration damping applications

Thermo-mechanical properties of polyethyleneimine (PEI) modified HNTs filled ABS/PVC composites

In this work, the surface properties of Halloysite nanotubes (HNTs) are successfully altered by using the Polyethyleneimine (PEI). Modified HNTs (m-HNTs) have successfully incorporated in Acrylonitrile-Butadiene-Styrene copolymer (ABS) and Poly Vinyl Chloride (PVC) blends with the help of injection molding machine, by melt mixing process. In order to enhance the thermo-mechanical properties of 90/10 ABS/PVC blends and its m-HNTs filled composites, the m-HNTs were varied in wt% like 0.5, 1, 1.5 and 2. The enhanced mechanical and thermal properties of the 90/10 ABS/PVC blends were observed at 1.5 wt% addition of m-HNTs. There was measurable difference in mechanical properties like tensile and impact strength of prepared composites, 74.46% and 36.73% respectively. However, it was also observed that thermal stability of the prepared blends in addition of m-HNTs was improved hand in hand which is explained with the help of Differential Scanning Calorimetry (DSC). The m-HNTs filled 90/10 wt% ABS/PVC can be used in different areas like pipe fittings, electric applications, automobile, etc.

Triphenyl Phosphite Regulates Degradation Behavior and Properties of Polylactic Acid/Ferric Chloride Blend

Triphenyl Phosphite Regulates Degradation Behavior and Properties of Polylactic Acid/Ferric Chloride Blend

Effects of a reduced-sodium added-potassium salt substitute on blood pressure in rural Indian hypertensive patients: a randomized, double-blind, controlled trial

High salt intake is a major modifiable risk factor of hypertension which is prevalent in India. It is not yet clear if salt substitutes reduce blood pressure (BP) among Indian hypertensive patients. Examine the acceptability, usage, and BP effects of a reduced-sodium and added-potassium salt substitute among hypertensive patients. We enrolled 502 participants with hypertension (aged 61.6±12.0 y, 58.8% women) from 7 villages in rural India. Participants were randomly assigned to receive either regular salt (100% sodium chloride) or the salt substitute (70% sodium chloride/30% potassium chloride blend), and advised to replace all home salt use. The primary outcome was the change in systolic BP (SBP) from baseline to 3 mo comparing the salt substitute and regular salt groups. Secondary outcomes included the change in diastolic BP (DBP), 24-h urinary biomarkers, and self-reported use and satisfaction with the study salt provided. A total of 494 (98%) participants completed 1 mo and 476 (95%) participants completed the 3-mo follow-up. At 3 mo, the salt substitute intervention significantly decreased the average SBP by 4.6 mmHg (95% CI: 3.0, 6.2, P< 0.001) and DBP by 1.1 mmHg (95% CI: 0.2, 2.1 mmHg, P=0.02). There was a significant increase in 24-h urinary potassium excretion in the salt substitute group by 0.24 g/d (95% CI: 0.12, 0.35 g/d, P< 0.001) and a decrease in the urinary sodium to potassium ratio by 0.71 (95% CI: 0.55, 0.87, P< 0.0001) compared with the control group. Participants reported that they used the study salt nearly every day of the week (mean±SD, 6.3±1.8 d) and rated the taste of the study salts similarly. The reduced-sodium added-potassium salt led to a substantial reduction in SBP in hypertensive patients, supporting salt substitution as an effective, low-cost intervention for BP lowering in rural India. This trial was registered at clinicaltrials.gov as NCT03909659.

Compressibility, Durability and Strength of Coal Fly Ash–Carbide Lime–Sodium Chloride Blends

Compressibility, Durability and Strength of Coal Fly Ash–Carbide Lime–Sodium Chloride Blends

A Comparative Experimental Study of Alternative Iron Sulfide Scale Dissolvers in the Presence of Oilfield Conditions and Evaluation of New Synergists to Aminopolycarboxylic Acids

SummaryIssues such as high corrosion rate, hydrogen sulfide (or H2S) generation, and scale reprecipitation have required the use of alternative dissolvers such as tetrakis(hydroxymethyl)phosphonium sulfate (THPS)–ammonium chloride (or NH4Cl) blend and chelating agents to dissolve iron sulfide (or FeS) scales. However, there are many aspects of these dissolvers that need investigation. This paper provides a guideline to select the best dissolver under various oilfield conditions by an extensive laboratory study. Furthermore, the iron sulfide scale removal is enhanced by the use of new synergists to the chelating agents.The application of THPS and diethylenetriaminepentaacetic acid (DTPA) in well tubulars or pipelines requires laboratory testing to determine the optimal conditions such as dissolver concentration, treatment time, and dissolver/scale (D/S) ratio (cm3/g) at 150°F. This evaluation considers oil-wet scales, mixed scales, presence of additives, and presence of salts during the treatment. Synergists such as potassium chloride (or KCl), potassium iodide (or KI), potassium formate (or HCOOK), sodium fluoride (or NaF), and potassium citrate (or K-Citrate) were added to ethylenediaminetetraacetic acid (EDTA), DTPA, and hydroxyethylethylenediaminetriacetic acid (HEDTA), and the scale solubility was evaluated at 150 and 300°F. Inductively coupled plasma–optical emission spectrometer analysis of the supernatant solution at various intervals of time up to 48 hours revealed the kinetics of the dissolution process. H2S generated from the scale dissolution process was measured using Draeger tubes. Corrosion tests helped in measuring the damage to the tubulars as a result of the dissolver’s contact with N-80 coupons.Solubility tests indicated the dissolver’s scale removal capacity at different concentrations. The work also accounted for the consumption of the dissolver for the scale removal. The optimal blend was chosen considering both the dissolution capacity and the dissolver consumption. For THPS–ammonium chloride blend, 0.75 mol/L THPS (30 wt%) and 2 mol/L NH4Cl (10 wt%) proved to be the optimum dissolver concentration at 150°F. Similarly, for DTPA, 0.4 mol/L K2-DTPA was evaluated to be the most effective dissolver concentration. The THPS–ammonium chloride blend was found to dissolve the iron sulfide slowly compared with K2-DTPA and 15% hydrochloric acid (HCl). The presence of crude oil on the scale hindered its solubility with K2-DTPA by 8%. The presence of calcium carbonate influenced higher selectivity of chelating the calcium ions by K2-DTPA. However, the overall fraction of scale removal was not affected. Adding corrosion inhibitors (CIs) did not affect the scale solubility significantly and also helped in maintaining an acceptable corrosion rate of N-80 coupons below 0.05 lb/ft2 at 150°F. The reaction of HCl and the iron sulfide scale generated 1,800 ppm of H2S in comparison with 0- and 10-ppm by THPS–ammonium chloride blend and K2-DTPA, respectively. Adding potassium iodide and potassium citrate to EDTA helped in improving the scale solubility at 150°F. Sodium fluoride improved the scale dissolution by EDTA and DTPA at 300°F.This paper addresses oilfield-like conditions on scale solubility by evaluating the role of mixed scale, scale mass, presence of hydrocarbons on the scale, and presence of monovalent/divalent ions in dissolver solution. A detailed and direct comparison of HCl, THPS–ammonium chloride blend, and DTPA in dissolving iron sulfide at various conditions enables easier selection of the dissolver for a field treatment. New synergists for iron sulfide scale dissolution are introduced in this paper. This work can help oilfield companies understand the nuances of applying different alternative iron sulfide dissolvers.