The performance of hydrophobic modified polyether thickener is similar to that of HEUR, and the products are Aquaflow NLS200, NLS210 and NHS300 from Hercules. modified polyurea thickener is a thickener developed by BYK. Its thickening mechanism is the action of both hydrogen bonding and end-group bonding.
Compared with general thickeners, it has good anti-settling and anti-sagging properties. According to the different polarity of end groups, modified polyurea thickeners can be divided into three types: low-polar polyurea thickeners, medium-polar polyurea thickeners and high-polar polyurea thickeners. The first two are used to thicken solvent-based coatings, while high polarity polyurea thickeners can be used in both high polarity solvent-based coatings and water-based coatings to thicken. Low-polar, medium-polar and high-polar polyurea thickeners are available as BYK-411, BYK-410 and BYK-420 respectively.
Polyamide-modified alkyd resins were developed in the 1950s and are considered to be a revolution in the “DIY” market. Usually at the end of the alkyd resin production process, the amide will react with the remaining acid functional groups. At this time, low molecular weight dimer acid-based polyaminoamines or polyamides can be used to modify the final resin. The formation of hydrogen bonds between them shows gelling properties. The paint using this resin looks like a solid, but when the brush is immersed in the paint bucket, especially when the coating film stretches, the hydrogen bonds are broken, and the polymer molecules are oriented in the direction of the brush and shear, thus forming a sticky flow. After a brief period of leveling of the coating film and the complete disappearance of the mechanical force, as the solvent evaporates, the gelation formed by ptfe wax uses the entanglement of the intermolecular chains makes the viscosity build up again.
The wax-modified resin is mainly used for air-drying alkyd, and it is rarely used for industrial drying paint. This is due to temperature sensitivity, and the use of polar and hydroxyl functional solvents will affect the thickening mechanism. The use of such thickeners, such as thixotropic acrylic or short/medium oil, isocyanate or urethane thixotropic alkyd, all give temperature-stable thixotropy and can be applied to modern high-solids styling coatings , Will not be destroyed by polar solvents.
Factors affecting the efficiency of driers
The film-forming conditions during coating construction and changes in coating formulations make the use of driers different, so they must be adjusted according to the actual situation. The factors that affect the dryness are: temperature, humidity, light, resin type, solvent, film thickness, pigments and driers. (1) Film-forming conditions  The temperature during film-forming has a greater influence on its drying speed. For example, the same paint dries slowly in winter and fast in summer.
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