Synthesis of halloysite nanotube based composite for enhanced ultraviolet shielding performance

Formulation and characterization of new ternary stable composites: Polyvinyl chloride-wood flour- calcium carbonate of promising physicochemical properties

Polymer nanocomposites have been investigated as lightweight and suitable alternatives to lead-based clothing. The present study aims to fabricate flexible, lead-free, X-ray-shielding composites using a polyvinyl chloride (PVC) matrix and different nanostructures. Four different nanostructures containing impure tungsten oxide, tungsten oxide (WO3), barium tungstate (BaWO4), and bismuth tungstate (Bi2WO6) were synthesized through various methods. Subsequently, their morphological characteristics were determined by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Also, energy-dispersive X-ray spectroscopy (EDS) analysis was performed to establish the presence of the filler in the PVC matrix. Two different weight ratios of these nanostructures (20% wt and 50% wt) were used to produce the PVC composites. To investigate attenuation parameters, the prepared composites were irradiated with X-rays at tube voltages of 40, 80, and 120kV. The results showed that the PVC composites containing 20% wt Bi2WO6 had the highest linear attenuation coefficient (µ) at all three voltages. Furthermore, they had the lowest half-value layer (HVL), tenth-value layer (TVL), and 0.5mm equivalent lead thickness values at each of the three voltages. The PVC composites containing 50% wt Bi2WO6 had attenuation coefficients greater than those reported for PbO at all three X-ray voltages. Among the studied tungsten nanostructures, bismuth tungstate had the best attenuation performance for X-ray protection. Additionally, this composite is light, flexible, and non-toxic, making it a promising alternative to lead aprons.

Ultraviolet (UV) radiation has a detrimental effect on the outdoor lifetime of PVC film materials. TiO2 nanoparticles, as commonly used UV absorbers, still suffer from poor transparency, high photocatalytic effect, and poor dispersion in PVC matrix. To mitigate these effects effectively, titanium dioxide nanorod @ silicon dioxide (TNr@SiO2) was synthesized and used as an anti-UV aging agent for polyvinyl chloride (PVC). The agglomeration effects of TiO2 nanoparticles in PVC films were solved by synthesizing TNr, and the catalytic effects of TiO2 was reduced by growing SiO2 on the TNr surface. Scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and UV-visible spectroscopy were utilized to demonstrate the excellent dispersion and low photocatalytic effects of the synthesized TNr@SiO2. Compared with pure PVC film, the color change of TNr@SiO2/PVC composite film is not evident after 800h of UV aging, and the retention of mechanical properties were 93.94%. Compared with TiO2/PVC, TNr@SiO2/PVC composite film has better transparency. Results show that TNr@SiO2 can maintain the properties of PVC better because the electrons of TNr@SiO2 are excited to form a positively charged hole after the absorption of UV light, and then the hole electron pairs are recombined and converted into thermal energy, which improves the durability of PVC. Therefore, this highly transparent TNr@SiO2/PVC composite film with low photocatalytic activity and high UV resistance will soon be applied in large-scale industrial production.

Preparation and interface structure study on dual-layer polyvinyl chloride matrix reinforced hollow fiber membranes

This study investigates the potential of incorporating CuO and Al nanoplates into a polyvinyl chloride (PVC) matrix to enhance the performance of medium voltage cables. The incorporation of nanoparticles into the PVC insulation material aims to improve the electrical, dielectric, and optical properties of the cable. The nanocomposite films were synthesized by dissolving PVC in tetrahydrofuran (THF) solvent and adding a mixture of 5 wt% CuO and Al nanoparticles. Fourier-transform infrared spectroscopy (FTIR) analysis confirmed the successful incorporation of the nanoparticles into the PVC matrix. The optical properties of the PVC/AlNPs and PVC/CuONPs + AlNPs nanocomposite films were characterized, revealing a decrease in band gap energy (4.35 eV) and Urbach tail energy (0.3702 eV) for the PVC/CuONPs + AlNPs film compared to the PVC/AlNPs film (4.5 eV and 0.41816 eV, respectively). Additionally, the PVC/CuONPs + AlNPs film exhibited higher absorption coefficients and increased electron delocalization and conjugation (carbon cluster value of 62.53). The dielectric properties of the CuONPs + AlNPs nanocomposites were investigated, with the sample containing 1.5% AlNPs demonstrating the highest AC conductivity (2.029 × 10−3 S/m), dielectric constant, and dielectric loss across the frequency range. Simulations of electric field distribution revealed that the PVC/CuONPs+1.5% AlNPs nanocomposite cable exhibited a more uniform electric field distribution compared to the PVC market cable, contributing to a reduction in electrostatic tension and a relative permittivity increase from 2.25 to 2.35. The electric potential distribution along the cable radius remained similar for both cable samples. These findings demonstrate the potential of nanocomposite insulation materials in enhancing the performance of medium voltage cables, paving the way for improved reliability, longevity, and efficiency.

Nanotubes as polymer composite reinforcing additive materials – A comparative study

A fluorescent biosensor based on acetylcholinesterase and 5-oxazolone derivative immobilized in polyvinylchloride (PVC) matrix

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.

ABSTRACTIn the present study, hexagonal boron nitride (h‐BN) nanosheets were first functionalized with hydroxyl groups (h‐BN‐OH), and then phosphonic acid groups were grafted onto the h‐BN surface (BNP) using aminotris(methylenephosphonic acid) (ATMP) through a condensation reaction. The BNP was then incorporated into a polyvinyl chloride (PVC) matrix to prepare PVC/BNP composites. Thermogravimetric analysis showed an increase in thermal stability, with BNP/PVC composites exhibiting greater resistance to degradation at elevated temperatures. The addition of BNP improved the dispersion and interfacial adhesion within the PVC matrix, as confirmed by Scanning Electron Microscopy (SEM). Furthermore, the PVC/BNP composites exhibited a 22.5% increase in tensile strength (21.2 MPa) and an 82% improvement in elongation at break (464%) compared to pristine PVC composites, which showed a tensile strength of 17.3 MPa and an elongation at break of 255%. Moreover, the addition of BNP notably improved the thermal conductivity from 0.18 to 1.50 W/m K as the BNP content increased from BNP‐0 to BNP‐4. These improvements in thermal stability and mechanical strength, as well as excellent migration resistance, make BNP/PVC composites highly promising for advanced applications.

This paper explores the fabrication of high performance & low-cost Membrane by incorporation of alumina and activated carbon in Polyvinyl Chloride (PVC) matrix using phase inversion technique. This study examined the various effects of the alumina (Al 2 O 3 ) and activated carbon (C) on the PVC matrix by several analytical techniques such as scanning electron microscope (SEM), Thermogravimetric Analysis (TGA), and contact angle. The synthesized membranes were used to separation of toluene from toluene-heptane mixtures using pervaporation technique and analysed the mass fraction of toluene in the permeate collected in the pervaporation setup using refractive index method. The results showed that the PVC/ 50% activated carbon/ 50% alumina membrane would be a promising alternative for separation of toluene from heptane-toluene solution. As an outcome, PVC/activated carbon/alumina-based membrane has given better separation of toluene from heptane-toluene solution as compared to other synthesized membrane.

To illustrate the mechanism of oxidizer treatment on wood cellulose reinforced plastic composites, moso bamboo particles were modified with potassium permanganate aqueous solutions and then filled in polyvinyl chloride (PVC) matrix. Mechanical properties and thermal behaviors of moso bamboo particles reinforced PVC composites (BPPC) were investigated. Results showed that tensile strength of BPPC achieved its maximum value of 13.79 MPa with 0.5% potassium permanganate treatment while modulus of rupture and modulus of elasticity reached their highest values of 30.36 MPa and 3261.89 MPa, respectively, at 0.2% concentration. Potassium permanganate treatment enhanced elongation at break and flexural deformation of BPPC. The melting temperature reached 190.8°C with 0.5% potassium permanganate treatment and the melting enthalpy of crystallization was reduced to 69.82 J/g with 0.2% potassium permanganate treatment. A uniform dispersion of moso bamboo particles in PVC matrix was obtained after potassium permanganate treatment. Low concentration potassium permanganate would oxidize hydroxyl groups of moso bamboo cellulose while too high concentration would degrade moso bamboo cellulose. POLYM. COMPOS., 35:1460–1465, 2014. © 2013 Society of Plastics Engineers

Copper(II)-selective potentiometric sensors based on porphyrins in PVC matrix

By establishing representative volume units of polyvinyl chloride (PVC) matrix composites filled with calcium carbonate (CaCO3) particles with different agglomeration degrees, finite element simulation analysis is conducted to predict the degree of improvement of the mechanical properties of the CaCO3/PVC composites by the dispersion degree of calcium carbonate particles. When the agglomeration coefficient is 0.4, the stress concentration phenomenon of the CaCO3/PVC composites is the weakest, and the stress distribution of the entire CaCO3/PVC composites is relatively uniform. At the same time, the reinforcement effect of the CaCO3/PVC composites’s stiffness is also the best, increasing by 13.8%.

Hybrid materials from Polyvinyl chloride (PVC) and titania were prepared using sol-gel technique. In-situ generation of titania network in the PVC matrix was carried out by introducing required amounts of tetrapropylorthotitanate (TPOT) followed by hydrolysis/condensation of TPOT in the matrix. Homogeneous and semi-transparent films were obtained by casting and solvent evaporation. Mechanical properties of these films up to 15 wt. % titania contents were studied. The results showed an increase in the Young's modulus, length at rupture and toughness of the unplasticised PVC. However, the tensile strength and stress at break point decreased with the addition of titania contents. Thermal stability of the material was studied using dehydrochlorination (DHCl) technique and thermogravimetric analysis. The PVC samples with small amount of titania were found to be more stable as compared with the pure PVC.

In the present study, it was focused on developing mechanically stronger and thermally more stable polyvinyl chloride (PVC) composites by using green reduced graphene oxide (GRGO) filler to strengthen the negative features of PVC. For this purpose, GRGO reduced by vitamin C (ascorbic acid) with antibacterial properties was selected as filler. The PVC/GRGO composites were produced via colloidal blending method at different amounts of GRGO in PVC matrix (0.1, 0.3, 0.5 and 1% by weight), while pure PVC was also produced for comparison. The XRD and FTIR results showed that GRGO incorporated in the polymer matrix; this finding was also evident in SEM analysis. TGA and DSC analyses showed that the composite with 1% loading content of GRGO provided an important improvement on the thermal stability. The tensile strength and hardness of the composite having 0.1% GRGO increased by 42% and 98%, respectively. SEM image of PVC/GRGO-0.1 composite showed the galleries of GRGO filled with PVC. As a consequence, thermal and mechanical properties of PVC can be altered by changing loading content of GRGO. Moreover, the GRGO may be a good candidate for substitution of harmful fillers for PVC-based products.