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The commercial success of electro‐deposition of aqueous coating is mainly concerned with the development of water‐soluble film forming polymers. The field of these water‐soluble polymer systems for surface coating application is growing rapidly and expanding vigorously and they are destined to play a leading role in the near future. This may be mainly attributed to regulations on emissions, environment and ecology. In doing so, the electrodeposition technique offers a remarkable assistance to these systems at comparatively low cost, low energy requirement and high utilization efficiency. Research workers have done work on water‐soluble alkyds, epoxies and acrylics.

The acute shortage coupled with tremendous increase in cost of various solvents used by paint industry and pollution becoming a serious concern has resulted in intensive study of water‐borne coatings. Water‐borne coatings ideally meet the needs for coating systems which do not cause atmospheric pollutions and at the same time help in conservation of precious and renewable petroleum resources. Many research workers have developed water‐soluble epoxies, alkyds and acrylics to make water‐based surface coatings.

The purpose of this paper is to explore the factors that affect the compactness of the mud filter cake, so as to prepare diaphragm wall slurry with good uniformity, small filtration loss and excellent recycling performance.

In this paper, the thickness, filtration loss and slurry viscosity of the filter cake are used as the characterization methods. The effects of pore depth, slurry specific gravity, intercalated metal ions, bridging polymer and water-soluble polymer on the compactness of the filter cake were studied.

The experimental results showed that the slurry's own pressure (pore depth) and specific gravity have little influence on the compactness of the filter cake and K⁺ can be considered as an auxiliary filtration loss reduction factor. Both the sulfonate copolymer and the potassium polyacrylate particle can significantly reduce the filtration loss of the slurry, which can effectively improve the filter cake compactness. Moreover, the composite application of potassium polyacrylate particles in the sizes of 80–100 and 150–200 meshes can exhibit a better filter cake compaction effect.

It solves the problems of high pulping cost, serious pollution of the environment, poor quality of filter cake formation and large filtration loss during the construction of the diaphragm wall, which improved the construction quality of the diaphragm wall.

For corporations that are considering a global joint venture, take a look at the strategy used by Hercules Inc. This company has had a history of successful international partnerships since the 1930s.

For conservation of petochemical solvents and reduction of air pollution, the water soluble polymers will play an important role in surface coating industry. The coatings based on water soluble polymers are thinned with water instead of petroleum solvent. Basically, the water based coatings may be made from oils, alkyds, polyesters, aminoes, phenolics, epoxies and acrylics. In spite of a large number of other synthetic resins being available for use in coating formulations, the alkyd resins surpass all of them in versatility, and low cost; combining a broad spectrum of performance properties with economy. Water soluble alkyd resins are similar to their solvent borne counterparts. The major difference is that their formulation is modified to introduce pendant carboxylic acid groups along the polymer backbone. These pendant acid groups can be neutralised with basic compounds to produce water solubility. Several workers studied preparation and evaluation of film characteristics of water soluble alkyd resins using various types of polybasic acids, polyhydric alcohols and fatty acids. The curing of these resins has been satisfactorily accomplished by stoving in presence of water soluble amino resins.

The encapsulation of electronic assemblies within thermoplastic polymers is an attractive technology for the protection of circuitry used in harsh environments, such as those experienced in automotive applications. However, the relatively low‐thermal conductivity of the encapsulating polymer will introduce a thermally insulating barrier, which will impact on the dissipation of heat from the components and may result in the build‐up of stresses in the structure. This paper therefore seeks to present the results from computational models used to investigate the thermal and thermo‐mechanical issues arising during the operation of such electronic modules. In particular, a two‐shot overmoulded structure comprising an inner layer of water soluble and an outer layer of conventional engineering thermoplastics was investigated, due to this type of structure's potential to enable the easy separation of the electronics from the polymer at the end‐of‐life for recycling.

Representative finite element models of the overmoulded electronic structures were constructed and the effects of the polymer overmould were analysed through thermal and thermo‐mechanical simulations. Investigations were also carried out to explore the effect of materials properties on the overmoulded structure.

Models have shown that some power de‐rating of components is required to prevent temperatures exceeding those in unencapsulated circuits and have quantified the benefits of adding thermally conductive fillers to the polymer. Simulations have also clearly demonstrated the benefits of foamed polymers in reducing thermal stresses in the assemblies, despite their poorer thermal conductivity compared with solid polymers.

The paper illustrates the thermal issues affecting the overmoulded electronics and gives some guidelines for improving their performance.

Measures the intrinsic viscosities, in acetone and tetrahydrofurane (THF) at different temperatures, of a terpolymer of methyl methacrylate, ethyl acrylate and methacrylic acid, prepared by semicontinuous emulsion polymerization (latex). Analyses data with the aid of the equations of Huggins, Kraemer, Martin, Schulz‐Blaschke and an equation recently suggested by Rao. Considers relationships between different parameters. By comparing uncleaned samples with samples purified by single precipitation or by dissolution and precipitation from THF, observes the effects of low‐molecular weight and water‐soluble on the intrinsic viscosities. Discusses solvent powers and effects of degree of purification and temperature on viscosity. Discusses polymer‐solvents interactions in terms of the acceptor/donor properties of the solvents. Concludes that purification of functionalized latices can lead to modifications of the original systems, through the elimination of different polymer chains.

To determine the inhibition efficiency and adsorption characteristics of two water soluble polymers namely polyvinyl alcohol (PVA) and polyethyleneglycol (PGE) as corrosion inhibitors of mild steel in H₂SO₄.

The inhibition efficiencies of PVA and PEG were evaluated using the weight loss and hydrogen evolution techniques at 30‐60°C.

The inhibition efficiency (I per cent) of the inhibitors increased with increase in concentration and temperature. The inhibitors (PVA and PEG) were found to obey Temkin, Freundlich and Langmuir adsorption isotherms from the fit of the experimental data at all concentrations and temperatures studied. The phenomenon of chemical adsorption is proposed from the activation parameters obtained. PEG was found to be a better inhibitor than PVA.

The mechanistic aspect of the corrosion inhibition can be better understood using electrochemical studies such as polarization and AC impedance spectra.

The findings may be useful in cooling water systems in industries under simulated conditions.

This paper provides additional new information on the inhibiting characteristics of PVA and PEG as promising corrosion inhibitors.

This paper aims to discuss the use of polyvinyl alcohol (PVA) as a water-soluble support material in desktop three-dimensional (3D) printing. Using a water-soluble material as one of the printing filaments in a dual-extrusion 3D printer provides the flexibility of printing support structures and rafts in complex components and prototypes. This paper focuses on the challenges of acrylonitrile butadiene styrene (ABS)–PVA dual-extrusion printing, and optimal settings and techniques for such hybrid printing.

Several hybrid ABS–PVA parts were printed using a commercial desktop 3D printer. An experimental study was designed to examine the solubility of the PVA support in water by varying four different parameters: length of time in water, water temperature, stirring rate and PVA surface area. The rate of PVA solubility in water was then used to examine its relationship with each parameter.

Numerous problems were encountered while printing ABS–PVA printing parts, including storing the spool of PVA in a dry environment, determining optimal extrusion and build plate temperatures and ABS–PVA adherence during dual extrusion printing. There is no strong literature to address these challenges. Hence, optimal settings and techniques for effective hybrid ABS–PVA were determined. Print yields were also recorded to examine the reliability of ABS–PVA printing.

The tendency of PVA to absorb moisture resulted in a number of build fails and prevented build times longer than 40 minutes. Future work can explore how to print PVA directly from a dry environment.

The optimal settings and techniques for dual-extrusion ABS–PVA printing that are presented in this paper can effectively be used to explore prototyping of geometrically complex parts with PVA as support material.

In addition to the practical implications, the results from this work are a valuable addition to the literature related to printing using water-soluble polymers such as PVA. The experimental methods and techniques of this paper can be used to assess the reliability of similar 3D printing technologies.