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Some factors of zinc stearate influencing the comprehensive performance of wood paint

wallpapers News 2021-01-11
In addition to polishing and transparency in coatings, zinc stearate also has other influencing factors such as diameter, dispersion, thickening, etc., which also affect the overall performance of wood paint.
1. The particle size of zinc stearate
Particle size is an indicator of the size of zinc stearate particles, which is generally measured by fineness. Usually, the simplest test of fineness is the fastest result is the fineness of the scraper. Generally, a certain proportion of zinc powder is added to the alkyd resin to disperse, then a little solvent is added to adjust the viscosity, and then the scraper fineness meter is used to test. The test result will be slightly larger than the actual fineness because the resin-coated powder occupies a certain thickness, but as long as the standard is comparable and repeatable, this test method can be used to measure whether the fineness exceeds the standard.
In the coating, the fineness of zinc stearates should not be too large, so that the effect of the spray plate will be full of particles protruding from the surface, and some places that are not polished will show unevenness. Sometimes zinc stearate contains coarse particles, which will also affect the aesthetics of the paint film to a certain extent.
2. Dispersibility of zinc stearate
In the production process of coatings, many zinc stearate manufacturers also mentioned the problem of dispersion. Under normal circumstances, the dispersion of zinc stearate in paint is not a problem, but in the production process of zinc stearate, there will be some indicators that will also affect the dispersibility to a certain extent, such as zinc stearate. If the acid value is too high, the temperature of the semi-finished product is too high, or the worker presses the package too seriously, the zinc powder will be poorly dispersed in the coating. At the same time, if the moisture in the zinc powder is too high, crystallization problems will occur, which is considered dispersibility. Not good, but using zinc stearate from Jiangxi Hongyuan Chemical will not cause this problem.
3. Zinc stearate thickens
The paint manufacturer does not accept the thickening of zinc stearate, because zinc stearate is added to the paint to make a finished product, its viscosity is determined, and the factory index has been set, even if the error is within ±500mP· s, so the method to test the thickening of zinc stearate is generally to use a rotary viscometer. If the deviation between the viscosity just after dispersion and the viscosity after a few hours is greater than 500mP·s, it is regarded as thickening. If the zinc stearate is thickened, the test of the finished product produced by the coating manufacturer will be very different from the time of use, and even the viscosity required for the original production of the coating is relatively large. Adding the thickening of zinc stearate, may cause The paint does not flow at all, especially the PE paint, which leads to scrap curing. Therefore, thickened zinc stearate cannot or is rarely used in coatings. This is also the case for many zinc stearate manufacturers but only a few manufacturers sell coating grade zinc stearate.