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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…
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…
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.
Water soluble epoxy resins were prepared from epoxy resin, linseed fatty acids, maleic anhydride, trimellitic anhydride, maleinised dehydrated castor oil and maleopimaric…
Water soluble epoxy resins were prepared from epoxy resin, linseed fatty acids, maleic anhydride, trimellitic anhydride, maleinised dehydrated castor oil and maleopimaric acid. Pigmented coating compositions for anodic electrodepositions were prepared from water soluble epoxy resins using red oxide of iron and zinc phosphate as pigment. The electrodeposition parameters such as voltage, time, solid content and pH value were optimised. The mechanical and chemical film properties of different electrocoating compositions were studied.
Water soluble epoxy‐amine adducts were prepared by reacting epoxy resin with diethanolamine in different molar ratios. These adducts were further partially esterified with…
Water soluble epoxy‐amine adducts were prepared by reacting epoxy resin with diethanolamine in different molar ratios. These adducts were further partially esterified with linseed oil fatty acids. Aqueous coating compositions for cathodic electrodeposition were prepared from epoxy‐amine adducts and esterified epoxy‐amine adducts separately. Film properties of cathodically electrodeposited coatings were evaluated and studied. It was observed that coatings based on 20% and 30% esterified epoxy‐amine adducts had good overall film properties.
Water soluble alkyds were prepared from phthalic anhydride, maleic anhydride, trimellitic anhydride and maleopimaric acid separately by monoglyceride process. Pigmented…
Water soluble alkyds were prepared from phthalic anhydride, maleic anhydride, trimellitic anhydride and maleopimaric acid separately by monoglyceride process. Pigmented electro coating compositions were prepared from water soluble alkyd resin, red oxide of iron and zinc phosphate. The anodic electrodeposition parameters such as voltage, time, solid content and pH were optimised. The mechanical and chemical properties of different electrocoating compositions were studied. The coating compositions prepared from water soluble alkyd resin based in maleopimaric acid showed good mechanical and chemical properties.
This paper deals with the synthesis of water soluble electrodepositable epoxy resins from maleopimaric acid and epoxy resin. Water soluble methylated urea formaldehyde…
This paper deals with the synthesis of water soluble electrodepositable epoxy resins from maleopimaric acid and epoxy resin. Water soluble methylated urea formaldehyde resin and melamine formaldehyde resin were also synthesised for curing purposes. The coating compositions were prepared from water soluble epoxy resins, water soluble MF resin, water soluble UF resin, red oxide of iron and zinc phosphate. Thereafter the optimum conditions for electrodeposition were determined in terms of voltage, time, solid contents, pH and bath temperature. These anodic electrocoatings had good film properties such as scratch hardness, flexibility, impact resistance and resistance to water, acid, alkali and solvent.
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…
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 purpose of this paper is to describe the synthesizing of polyesteramide (PEA) resins using an acid functional acrylic copolymer (ACR) and hydroxy ethyl fatty amide…
The purpose of this paper is to describe the synthesizing of polyesteramide (PEA) resins using an acid functional acrylic copolymer (ACR) and hydroxy ethyl fatty amide (HEFA) of dehydrated castor oil (DCO) and to study the effect of HEFA on the performance properties of the coating films of PEA resins.
The PEA resins are synthesised by using ACR (synthesised by using butyl methacrylate (BMA) and maleic anhydride (MA)), and HEFA. Different formulations are developed by using ACR and HEFA. The coatings are made using xylene/acetone as a solvent. These coatings are applied on mild steel panels and are cured at 110°C. Various mechanical, optical and chemical properties of the coating films are evaluated.
The study reveals that, HEFA of DCO is used successfully as a cross‐linking agent for the ACR to form the PEA resins. Incorporation of long chain fatty acid (C18) moieties of the fatty amide in the PEA resins backbone is thought to serve as flexibliser, which lead to improved mechanical and chemical properties of the films. The optimum results are obtained from composition three of copolymer A having (3:1) (ACR:HEFA) molar ratio.
The PEA resins synthesised here are made up of ACR (synthesised by using BMA and MA), and HEFA of DCO. Besides, this ACRs can be synthesised from acrylic acid. In addition to this, one can also use HEFA synthesised from other oils.
This method provides a simple solution for the synthesis of PEA resins and resulting to their improved mechanical properties. The developed product is also an environment friendly product.
The method developed here for the synthesis of PEA resins form ACRs and HEFA is unique and can be used as an effective surface coating material. These studies will help to develop low volatile organic compounds product which could find numerous industrial applications in surface coatings for metal surfaces.
Current virtual simulation platforms provide various tools to generate non-immersive simulation processes purposefully in different domains. The generated simulation…
Current virtual simulation platforms provide various tools to generate non-immersive simulation processes purposefully in different domains. The generated simulation processes are adopted for analysis, presentation, demonstration and verification. In the virtual maintenance domain, this intuitive and visual method has benefitted product maintainability design and improvement. Generating an ideal and reasonable non-immersive virtual maintenance simulation is always time-consuming because of the complicated human operations and logical relationships involved. This study aims to propose a semiautomatic approach to increase efficiency in non-immersive virtual maintenance simulation implementation.
The methodology analyzes the general catalogs of common maintenance tasks and explores the corresponding secondary development approaches of simulation tools that can achieve motion simulation in virtual environments, by focusing on the diversity, complexity and uncertainty in non-immersive virtual simulation process generation. Afterward, a single virtual human motion can be generated by controlling the parameters and indices of the simulation tools. Subsequently, all of the generated single motions are connected logically to simulate the entire maintenance process.
Instead of selecting various tools, such as that in a traditional method, the proposed methodology analyzes and integrates the necessary basic parameters considering the characteristics of virtual maintenance simulation for a target maintenance activity.
The user can control the predefined parameters to generate the simulation combining several other simple operations in virtual environments. Consequently, the methodology decreases simulation tool selection and logic consideration and increases efficiency to a certain extent in non-immersive virtual maintenance simulation generation.
The binder or media component of surface coatings can be subdivided into two broad groups, non‐convertible and convertible, which differ in their mode of film formation…
The binder or media component of surface coatings can be subdivided into two broad groups, non‐convertible and convertible, which differ in their mode of film formation. Binders of the non‐convertible type do not undergo chemical conversion reactions whenthey cure, and film formation here involves loss or evaporation of a volatile solvent and concomitant deposition of the solid binder. Important members of this group are the rubber derivatives and the many examples of vinyl copolymers; some recent developments in the technology of these polymers were described in the previous article in this series. This article will consider the convertible media used in coatings, where film formation involves some form of chemical reaction. Commencement of this reaction is dependent upon either the presence of a suitable initiator, or by exposure to some form of radiant energy, which causes the binder (in the form of a monomer or partially‐polymerised component) to rapidly polymerise. This polymerisation reaction can take one of several forms though the result is the same; the binder and hence the liquid paint is converted into a solid material which is substantially insoluble in the original carrier solvent. This review will consider some of the recent literature concerned with three important members of the convertible group of media; alkyd, epoxy and polyurethane resins.