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A kind of the Z-6020/E-44 modified waterborne hydroxyl acrylate resin (Z-WEA) and its application in volatile organic compound-free waterborne coatings were prepared.

The Z-6020/E-44 modified waterborne hydroxyl acrylate resin (Z-WEA) was obtained dropwise by adding a mixed solution of methyl methacrylate, n-butyl acrylate, hydroxyethyl methacrylate, acrylic acid and an initiator into a pre-prepared solution of isopropyl alcohol and E-44 and by semi-continuous solution polymerization, and this chain was further extended with organosiloxane (Z-6020) through graft copolymer, which was then neutralized with organic base and dispersed with water, with waterborne amino resin curing agent to form a film, and the properties were tested.

The results showed that when the dosage of initiator was 2.5% accounts for the total acrylic monomer, the hydroxyl content was 10%; the dosage of E-44 was 16%; the dosage of Z-6020 was 6%; the mass ratio of hard and soft monomer was 2.0:1; the neutralization was 100%; Z-6020/E-44 modified waterborne hydroxyl acrylate resin (Z-WEA) had excellent dispersion performance in water and storage stability; water absorption of cured film was 7.8%; pencil hardness reached 5H; adhesive force was 1 level; and the film was uniform and endowed with remarkable heat resistance, high gloss and good fullness.

This paper established a method to synthesize Z-6020/E-44 modified waterborne hydroxyl acrylate resin (Z-WEA) with green surfactants that can be used in the coatings, adhesives, finishing agents and so on.

This paper provides a method of preparing Z-6020/E-44 modified waterborne hydroxyl acrylate resin (Z-WEA) and with waterborne amino resin curing agent to form a film, and the film is uniform and endowed with remarkable heat resistance, high gloss and good fullness and meets the requirements of high-grade paint.

This paper aims to deal with the experimental and numerical investigations of the fire protection performance of a waterborne intumescent coating (IC) on structural steel in case of natural fires. Based on own small-scale laboratory tests, an advanced numerical model is developed to simulate the fire protection performance of the investigated coating in case of arbitrary fire scenarios. The insulation efficiency of the coating is described within the model by temperature and heating rate-dependent material properties, such as expansion factors, thermal conductivity and heat capacity. The results of the numerical model are compared to own large-scale fire tests of an unloaded I-section beam and column.

As natural fires can show arbitrary regimes, the material properties of the waterborne IC are investigated for various heating rates. Based on these investigations, a material model for the IC is implemented in the finite element program ABAQUS. With the help of user subroutines, the material properties of the coating are introduced for both the heating and cooling phase of natural fires, allowing for two- and three-dimensional thermomechanical analyses of coated steel elements.

The results of the performed small-scale laboratory tests show a heating rate-dependent behavior of the investigated coating. The mass loss as well as the expansion of the coating change with the heating rate. Moreover, the material properties obtained on small scale are valid for large scale. Therefore, a material model could be developed that is suitable to reproduce the results of the large-scale fire tests. Additionally, with the help of the numerical model, a dimensioning approach for the dry film thickness (DFT) of the investigated coating is derived for arbitrary natural fires.

The material properties presented in this paper are only valid for the investigated waterborne IC and the parameter area that was chosen. However, the developed modeling approach for the fire protection performance of ICs is general and can be applied for every coating that is part of the intumescent product family.

Until now, only few research works have been carried out on the fire protection performance of ICs under non-standard fire exposure. This paper deals extensively with the material properties and the material modeling of a waterborne IC exposed to natural fires. Especially, the laboratory examinations and the numerical simulations are unique and allow for new evaluation possibilities of ICs.

The purpose of this study is to prepare a new self-emulsified waterborne epoxy hardener which can emulsify the liquid epoxy resin in aqueous media without addition of acid neutralizers.

Two synthetic steps were adopted to prepare novel self-emulsified amine-epoxy adduct type hardener composition based on the reaction of a commercially available polyetheramine, bisphenol A epoxy resin and triethylene tetramine. The different factors affecting the synthesis of the waterborne epoxy hardener were explored by emulsifying and curing properties. The process and products were analyzed and confirmed by FIRT.

Compared to an introduction of polyether as a hydrophilic segment in previous literature, whose reaction required Lewis acid catalysts and strict control of the presence of water, the introduction of polyetheramine to obtain a novel self-emulsified waterborne epoxy hardener were concise and convenient by mere two amine-epoxy addition steps in this research. Moreover, the final product offered good film formation with a practical value of mechanical properties, glass transition temperature and water-resistant property.

The self-emulsified waterborne epoxy hardener can be used to prepare water-resistant waterborne coatings from liquid epoxy resins while also providing the option of zero VOC formulations.

Introduction of hydrophilic polyether amine to prepare self-emulsified waterborne epoxy hardener without acid neutralizers has not been systematically studied previously.

The flammability of epoxy resin is a major disadvantage in applications that require flame resistance. Epoxy monomers and hardeners containing flame-retardant elements are molecularly incorporated in the resin network are expected to exhibit better flame resistance than those borne on an additive approach. In recent years, because of health and environmental regulation, the use of waterborne coatings has received many attentions. However, waterborne epoxy resin curing agent with excellent flame retardancy has been seldom reported. The paper aims to study the preparation of waterborne P-N-containing epoxy resin curing agent and its performances (P-N – phosphorous and nitrogen).

Waterborne P-N-containing epoxy curing agent was prepared in this study using reactive flame retardant 10-(2,5-dihydroxyphenyl)-9,10-dihydro-9-xa-10-phosphaphenanthrene-10-oxide, liquid epoxy resin, triethylenetetramine and butyl glycidyl ether at the mole ratio of 1.0:2.0:2.0:2.0.

The results show that the epoxy thermoset from the prepared P-N-containing curing agent presents good flame retardancy and can pass the V-1 rating, and the cured epoxy thermoset film presents excellent performances such as water resistance, adhesion, impact resistance and pencil hardness. This study provides useful suggestions for the application of the water-borne flame retardancy epoxy resins in coating industry.

Each step of products during the preparation of waterborne P-N-containing epoxy curing agent cannot be accurately tested.

This method for synthesis of waterborne P-N-containing epoxy curing agent is novel and could be used for various applications in epoxy coating industry.

The silicone modifications of two-component epoxy resin coatings are commonly built on epoxy resins rather than on epoxy curing agents. The silicone-modified epoxy curing agent system is rarely reported yet. This study aims to prepare the polysiloxane (PS)-modified waterborne epoxy coatings based on aqueous curing agents technology.

Waterborne epoxy curing agents with different contents of terminal epoxy PS were synthesized by reacting with triethylenetetramine, followed by incorporating of epoxy resin (NPEL-128) and polyethylene glycol diglycidyl ether. The waterborne epoxy coatings were prepared with the above curing agents, and their performance was investigated through thermogravimetric analysis, scanning electron microscopy, mechanical characterization, gloss measurement, chemical resistance test and ultraviolet (UV) aging experiment.

The results showed that the epoxy coating prepared by silicon-modified curing agent has higher gloss, better chemical resistance and UV resistance than the coating from unmodified curing agent with terminal epoxy PS and commercially available waterborne epoxy curing agent (Aradur 3986), as well as the competitive mechanical properties and heat resistance. Reduced water absorption on fibrous paper was also obtained with the help of silicon-modified curing agent.

These findings will be valuable for resin researchers in addressing the modification issues about waterborne epoxy resin and curing agent.

The purpose of this paper is to evaluate the role of encapsulation temperature on the preparation of silica-encapsulated waterborne aluminium pigments.

The waterborne aluminium pigments were prepared with H₂O₂ as anchoring agent and siloxane used as precursors in pH = 9.0 medium at different temperatures. The anchorage and compactness of silicon which on aluminium surface were characterized by optical microscopy, scanning electron microscopy and N₂ adsorption-desorption. The anticorrosion property was characterized by the volume of produced hydrogen as a function of time.

The effect of encapsulation temperature on anticorrosion property of aluminium pigments is reflected from the anchorage and the compactness of silica on aluminium surface. Furthermore, when encapsulation temperature is 45-50°C, the silica platelets uniformly anchored on the aluminium surface as a dense film, which show the best anticorrosion property. Lower and higher encapsulation temperatures cause the silica platelets to agglomerate rather than anchor on the aluminium surface, which is unfavourable for the anchorage and the formation of compact silica film. The use of product in waterborne coatings gives a higher glossiness than that of raw material.

Only pH = 9.0 medium was explored, and the other pH medium could result in different optimum temperatures.

The investigation results provide theoretical basis for obtaining excellent waterborne aluminium pigments.

The method of investigating corrosion resistance mechanism of aluminium pigments based on anchorage and compactness is novel.

New raw materials which are announced each year for coatings are largely variations on products that have existed for a long time. Very little basically new has appeared for several years, a consequence of a general trend in the chemical industry in which the introduction of new products has decreased markedly. This is not to say, however, that there have not been marked improvements in many areas, and one such area comprises waterborne vehicles.

The purpose of this paper is to prepare waterborne UV-curable pigment pastes for cotton fabric printing.

O/W (oligomer-in-water) emulsions of polyurethane acrylate (PUA) oligomer in sodium dodecyl benzene sulphonate (SDBS) aqueous solution were prepared by ultrasonic emulsification method.

The present work studies various factors affecting the stability and droplet size of the O/W emulsion stabilised by SDBS. The optimal emulsifier concentration was 2.5 per cent, under which condition the stability of the emulsion increased as the emulsifier content increased, with a subsequent decrease in the droplet size of the emulsion, while above which emulsion agglomeration occurred. Increasing the power and duration of ultrasonic dispersion resulted in increased emulsion stability and decreased droplet size, while increases in the oligomer content reduced the emulsion stability. Darocure 1173 mixed with PUA and then emulsified in the SDBS aqueous solution guaranteed uniform dispersion of the photoinitiator, resulting in faster curing speed.

This paper presents a new method for making waterborne externally emulsified oligomers for UV curing, and finds that it is easy to convert the existing oligomers into waterborne equivalents by this method. Cotton fabrics printed with the oligomer emulsion based pastes were found to have good colour strength and crockfastness.