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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.

The purpose of this paper is to investigate the effects of the components of whey‐protein based aqueous polymer‐isocyanate (API) adhesives on the bond strength.

The bond test (according to the JIS K6806‐2003 standard), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were used to characterise the whey‐protein based API adhesives with various formulations and processing technologies.

The good bond strength of the optimised whey‐protein based API adhesive was attributed to the formation of strong chemical bonds in the bondline and to the additions of polyisocyanate, polyvinyl alcohol (PVA) and nano‐CaCO₃ powder that improved adhesive cohesive strength by either chemical crosslinks or mechanical interlocking. The blending procedures of whey protein, PVA, polyvinyl acetate (PVAc) and p‐p‐MDI had great impacts on the performances of the whey‐protein based API adhesives.

SEM micrographs showed that the effects of blending processes on the bond strength, pot life and colour might be attributed to the particle size of hydrophobic p‐MDI droplet and p‐MDI distribution in the protein‐PVA matrix.

The study lays the foundations of the formulation design and the processing technology for preparing whey‐protein based API adhesives.

The effects of the components of whey‐protein based API adhesives and the effects of blending processes on the bond strength were investigated by means bond strength evaluation, FTIR and SEM analyses; whey protein is utilised successfully to prepare novel API adhesives for structural uses.

The new raw materials which have appeared in the two years have been heavily weighted towards water‐based coatings. Thus, these will be emphasised in the discussion that follows. Also of considerable interest are a variety of new solvent‐based acrylic raw materials. Beyond this, there has been only modest variations of existing products useful in the formulation of coatings.

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.

Each year the paint chemist avidly watches the literature for announcements of new raw materials with which he can extend the functionality of his products. Following are brief descriptions of some of the newer raw materials introduced recently.

The purpose of this paper is to study interactions between water‐based polymer isocyanate (WPI) adhesive and bamboo by means of differential scanning calorimetry (DSC).

The method of adapting new reference substance replacing aluminium was used due to the special characteristic of WPI adhesive when studying reactions between WPI adhesive and bamboo.

The methods of changing reference substance could counteract effect of water in the sample on DSC measurement. The results of DSC analysis showed that hardener of WPI adhesive can react with water and also with ‐OH in bamboo and matrix of WPI adhesives. That is to say that a competition exists between urethane formation (covalent bonding of isocyanate with hydroxyl groups in bamboo and matrix in WPI adhesive) and urea formation (isocyanate consumption due to the reaction with water) during the operation of glued bamboo products.

The method of changing reference substance can be used for other DSC samples in which water cannot be conveniently removed, but this method requires that weight of reference substance to be exactly the same as the sample used in DSC measurement. So accuracy of weighing was very important in this DSC measurement.

The method developed in this paper provides a simple and practical solution to studying interactions between WPI adhesive and bamboo by means of DSC.

Changing reference substance was brought forward as a new method of counteracting effect of water in the sample on DSC measurement. The understanding gained through this study could help improve bonding properties of glued bamboo products.

This paper aims to study the Improvements in self-cleaning property of the white acrylic water-based paint by addition of different percentages of three commercially available titanium dioxide (TiO₂) nanoparticles as additives. Then, due to the risk of destruction of polymeric materials in the presence of nanoparticles, degradation of dry paint film samples was investigated for 15 days using two important chalking and yellowing factors. Finally, the TiO₂-modified paint sample with the best performance and optimum percentage of TiO₂ nanoparticles that produced desired self-cleaning and dry film properties was introduced.

Self-cleaning and dry film properties of white acrylic water-based paint were investigated by addition of three various types of commercial available TiO₂ nanoparticles (SSP-25, STA-100 and KA-100). X-ray diffraction, transmission electron microscopy and Brunauer–Emmett–Teller were used for characterization of TiO₂ samples. Colorimetric tests in decolourization of C.I. Basic Red 46 (BR46) were used for determination of self-cleaning properties of TiO₂-modified paints in comparison with unmodified paint sample. Also, paints defects such as chalking and yellowing were tested along two weeks.

The results indicated that, in all types of TiO₂ nanoparticles, by increasing the amount of TiO₂ in modified paint, self-cleaning property of the samples was enhanced. The paint containing SSP-25 indicated better self-cleaning properties than others due to its larger surface area. However, its usage above 3.5 weight per cent caused yellowing and chalking defects in dried paint film.

In this research, TiO₂-modified paint sample with the best performance in both self-cleaning and mechanical properties was selected among the nine sets of prepared paint samples. All the materials used in this research such as acrylic resin and three types of TiO₂ nanoparticles are of industrial grade. Therefore, the introduced TiO₂-modified paint sample has the potential for the commercial production as a building exterior paint.

In the present study, an attempt at introducing a self-cleaning paint sample with acceptable mechanical properties using three types of commercially available TiO₂ nanoparticles as additives and industrial grade of acrylic resin which is the most commonly used water-based resin in building paints, as binder. As far as it was searched in the literatures, the parallel study of the self-cleaning and mechanical properties of paints has not been reported as noteworthy. Self-cleaning property of the acrylic water-based paint samples was investigated by adding three types of the commercially available TiO₂ nanoparticles. Also considering the possible detrimental effects of TiO₂ nanoparticles on polymeric materials and consequently on physical properties of the paint, chalking and yellowing factors in dried paint samples were evaluated.

Legislation is currently the key driver in the coatings industry. Reduction of the volatile organic content (VOC) of coating systems is a main aim. This may be achieved by designing the resin and coating with water as the carrying solvent. Reduction of resin viscosity to enable high solids coatings production is another route. The design and development of legislation‐compliant paint formulations based on water‐based epoxy resin systems and high solids polyurethane topcoats is discussed. A short review and discussion of the weaknesses of traditional accelerated test methods including salt‐spray, QUV^TM and Prohesion^TM used to check coating performance is presented. Some simple reaction and degradation mechanisms are shown.

The purpose of this paper is to evaluate naturally occurring phytic acid (PA) as a green-water-based lubricant.

Lubrication is studied using a ball-on-disk tribometer with silica glass against silicon nitride contact, and the friction coefficient and wear are measured in the boundary lubrication regimes.

Excellent lubrication performance was found by using PA aqueous solutions. After the running-in process, the sliding coefficient of friction could drop to as low as 0.01 with a quite low concentration of 7.5 × 10⁻⁴ M. The lubricating performance of PA solution could be further improved by increasing PA concentration. The work suggests that the excellent lubricity of PA in aqueous solution can be mostly contributed to its adsorption on the silica surface.

The paper shows that the natural products could be used as water-based lubricant additives.

Polyurethane (PUR) foam parts are traditionally manufactured using metallic molds, an unsuitable approach for prototyping purposes. Thus, rapid tooling of disposable molds using fused filament fabrication (FFF) with polylactic acid (PLA) and glycol-modified polyethylene terephthalate (PETG) is proposed as an economical, simpler and faster solution compared to traditional metallic molds or three-dimensional (3D) printing with other difficult-to-print thermoplastics, which are prone to shrinkage and delamination (acrylonitrile butadiene styrene, polypropilene-PP) or high-cost due to both material and printing equipment expenses (PEEK, polyamides or polycarbonate-PC). The purpose of this study has been to evaluate the ease of release of PUR foam on these materials in combination with release agents to facilitate the mulding/demoulding process.

PETG, PLA and hardenable polylactic acid (PLA 3D870) have been evaluated as mold materials in combination with aqueous and solvent-based release agents within a full design of experiments by three consecutive molding/demolding cycles.

PLA 3D870 has shown the best demoldability. A mold expressly designed to manufacture a foam cushion has been printed and the prototyping has been successfully achieved. The demolding of the part has been easier using a solvent-based release agent, meanwhile the quality has been better when using a water-based one.

The combination of PLA 3D870 and FFF, along with solvent-free water-based release agents, presents a compelling low-cost and eco-friendly alternative to traditional metallic molds and other 3D printing thermoplastics. This innovative approach serves as a viable option for rapid tooling in PUR foam molding.