Behavior Of Polyethylene Glycol Research Articles

Preparation and Tribological Behaviors of Modified Rice Husk Carbon/MoS2 Composite Particles as a Functional Additive in Polyethylene Glycol

Rice husk carbon/molybdenum disulfide (RHC/MoS2) nanoparticles were prepared by a chemical precipitation method in order to comprehensively utilize the rice husk. 3-Aminopropyl trimethoxysilane (ATS) was used as a surface modifier to promote the dispersion capability of RHC/MoS2 particles in polyethylene glycol. The tribological behavior of polyethylene glycol (PEG) with different amount of modified particles was investigated using a ball-disk tribometer at the different velocities and loads. A three-dimensional (3D) laser scanning microscope (LSM) and x-ray photoelectron spectroscopy (XPS) were used to clarify the friction and wear mechanisms of modified composite particles in PEG. Results show that the modified RHC/MoS2 has good friction characteristics and dispersion in PEG. Modified RHC/MoS2 particles can effectively improve the wear resistance and friction reduction properties of PEG. The optimal additions of two kinds of particles are both 0.5 wt%. Friction and wear mechanism of composite particles were ascribed to the tribofilm that came from the components of composite particles.

INVESTIGATION ON THE EFFECT OF THE POLYETHYLENE GLYCOL ON THE ELECTROPHORTIC DEPOSITION OF ALUMINA AND ZIRCONIA

This work is a study of the effect of polyethylene glycol (PEG) on electrophoretic deposition) EPD) of alumina and zirconia particles. The effect of polyethylene glycol as a binder material and the toluene as a dielectric liquid, on the pH of suspension, the final thickness and green density of the deposed parts were studied. There was a difference in the behavior of polyethylene glycol when added for the alumina suspension and the zirconia suspension. The increase in polyethylene glycol was useful to deposit the zirconia more than alumina. The pH for both alumina and zirconia suspension increases with the increase of polyethylene glycol content and with the addition of toluene due to increase of the OH– concentration in the suspension. This increase of pH enhances the particle surface charge and enhances the deposition rate, which led to the increase of density of the deposit

Powder Injection Molding of Mullite: The Study of Binder Dissolution Behavior during Debinding Step Using Statistical Methods

The purpose of this work is to use the statistical methods including linear regression and statistical hypothesis test to study the dissolution behavior of polyethylene glycol (PEG), a water-soluble binder, during debinding step of the green specimens of mullite formed by powder injection molding (PIM). Two systems of composite binders were investigated including (A) 80 wt% polyethylene glycol (PEG) and 20 wt% polyvinyl butyral (PVB) and (B) 78 wt% PEG, 20 wt% PVB, and 2 wt% steric acid (SA)The lab-scale plunger type PIM machine was used to prepare the green specimens consisting of mullite powder and the composite binder. The possible solid loadings of the green specimens that could be prepared by this machine were 50, 52, and 54 vol% mullite (50, 48, and 46 vol% binder). The debinding was done by soaking the green specimens in the warm water at 40 or 60 oC to remove PEG. At level of significance 0.05 for statistical analysis, the dissolution behavior of PEG can be fitted with Avarami equation. In addition, from the Avarami equation obtained from each experimental condition, the dissolution rate of PEG was independent of the parameters used in this study including solid loading in the green specimens, water temperatures for debinding, and composite binder systems.

Miscibility Behavior of Poly Ethylene Glycol or Poly Ethylene Succinate/Chlorinated Poly Vinyl Chloride Blends Studied by Dielectric Relaxation Spectroscopy

The miscibility of chlorinated poly vinyl chloride (CPVC) and poly ethylene glycol (PEG) or poly ethylene succinate (PES) had been investigated using dielectric relaxation spectroscopy (DRS) over frequency and temperature ranges; 10 kHz - 4 MHz and 300 - 450 K, respectively. Three relaxation processes namely ρ-, α’-, and α-relaxation processes were observed for tan(δ) and the electric modulus M" of pure components and blends. The first one was attributed to the space charge polarization or the Maxwell-Wagner polarization. The second one was related to the amorphous regions located between the lamellar crystal stacks. The third one was due to the micro-Brownian motion of CPVC main chains. This process was found to be dependent in respect of temperature and frequency. The molecular dynamics of α-relaxation process were influenced by blending, i.e., the dielectric strength (De), the peak broadness, and the peak maximum of tan(δ) were found to be compositional dependent. Electric modulus analysis reveals that there is a role of electrode polarization for the dielectric relaxation.

Preparation and Investigation on the Adsorption Behavior of Polyethylene Glycol Modified Sodium Alginate Porous Membrane Adsorbent for Cr(III) Ions

- In this study, sodium alginate based porous membrane adsorbents (GA/SA) were prepared by using polyethylene glycol (PEG) as porogen and glutaraldehyde (GA) as cross-linking agent. The prepared GA/SA were used to remove Cr (III) ions from wastewater to test its adsorption performance. The proposed technique is very convenient for operation. The batch experiments were performed to investigate the adsorption kinetics of Cr (III) ions from aqueous solution under different conditions, such as the amount of PEG in the GA/SA, pH of solution, initial Cr (III) ions concentration, adsorbent dose and contact time. The GA/SA exhibited the maximum uptake capacity of 57.4 mg/g under the optimal condition. The experiment results show that the adsorption is high pH-dependent. Various kinetic models were applied to examine the mechanism of adsorption processes. Pseudo-second-order kinetic model exhibits the best correlation with experimental data. The kinetic experiment results show that the adsorption of Cr (III) ions is a multistep limited adsorption process. Out of Langmuir and Freundlich isotherm equations, the batch equilibrium data are better described by the Freundlich isotherm equation. The prepared GA/SA could be considered as a potential low-cost and high-effective bio-sorbent for removing and recovering Cr (III) ions from the aqueous solutions.

Investigation of Copper Plating and Additive Interactions in the Presence of Fe3+/Fe2+ Redox Couple

The impact of the ferric/ferrous (Fe3+/Fe2+) redox couple on the behavior of polyethylene glycol (PEG) and bis-(3-sulfopropyl) disulfide (SPS) during copper electrodeposition is investigated. The Fe3+/Fe2+ couple is used in plating of copper onto printed circuit boards and may have advantages when implemented for on-chip metallization of copper. Experiments show that in the presence of Fe3+/Fe2+ the suppressing behavior of PEG does not change; in contrast, the accelerating activity of SPS increases when Fe3+/Fe2+ is present in a copper-plating bath. Furthermore, potentiostatic experiments suggest that SPS interacts with Fe2+ ions in the bulk electrolyte, probably to produce 3-mercapto-1-propane sulfonic acid (MPS) at low ppb levels.

The self-diffusion behavior of polyethylene glycol in cartilageas studied by pulsed-field gradient NMR

The self-diffusion behavior of the polyethylene glycol (PFG) polymer in bovine nasal cartilage was studied by pulsed-field gradient (PFG) nuclear magnetic resonance (NMR). PFG NMR allows the determination of the mean square displacement of molecules in a given diffusion time (in the range of a few milliseconds up to seconds), monitors distances in micrometer scales and has the advantage of being non-invasive. Moreover the application of pfg nmr does not require concentration gradients In a previous study, PFG NMR was used to investigate the self-diffusion behavior of the PEG polymer in cartilage at very highconcentrations. In this study, much lower PRG concentrations were used in order to detect the effects of the structural composition of the cartilage tissue more efficiently. It will be shown that at very low (<10 wt.-%) PFG concentrations, the effect of restricted polymer diffusion in cartilage is negligible. The self-diffusion coefficients (SDC) are primarily influenced by the water content and the molecular weight (MW) of the appliec. PFG. The problems encountered with PFG NMR diffusion studies using high field gradients as well as in vivo aspects of this study are discussed.

Phase change behavior of polyethylene glycol in blends with cellulose

Abstract Thermodynamic properties and phase change behaviors of polyethylene glycol (PEG) in blends with cellulose (CELL) were found to be completely different than those of pure PEG. When the CELL fraction of the blend was larger than 5 wt%, PEG within the blend did not melt into a liquid state, as was the case with pure PEG, even at a temperature over 50°C above its melting point. Instead of fusion, a solid-solid phase transition was found in these PEG-CELL blends with an enthalpy as large as 100 J/g.