Dispersion of fine talcum powder and its application in waterborne coatings

1. Dispersion study of fine talcum powder

During the research of fine talcum powder dispersion, the dispersibility can be well grasped by means of sedimentation experiment analysis. In this process, the fine talc powder was dispersed and settled using a 10 mL measuring cylinder. In this process, the concentration of the dispersant was controlled at about 2% and the volume was 10 mL. After the fine talc powder and the dispersing agent were disposed, they were dispersed by ultrasonication for 30 minutes, and then placed for 10 hours, and the thickness of the sedimentation layer of the fine talc powder was counted. After the fine talc is settled, the adsorption isotherm of the dispersant is measured. In the measurement process, the steps are as follows:

(1) A dispersant solvent having a concentration of 1% was placed and its wavelength was measured. In the wavelength measurement process, the ultraviolet visible light luminosity can be used for measurement, and the measurement results are recorded;

(2) The standard curve design and drawing of the dispersant adsorption isotherm are mainly determined by absorbance during the design and drawing process. In the dispersant ratio process, the ratio of different mass fractions was taken, and the ratios were 0.01%, 0.04%, 0.07%, 0.1%, 0.3%, and 0.5%, respectively.

(3) A 2% talc suspension was prepared at a dose of 10 mL, which was ultrasonically dispersed according to the concentration of the dispersant. In the measurement of the concentration of the dispersant, the measurement is performed using a standard curve to make the concentration of the dispersant more accurate.

When determining the adsorption isotherm value of the dispersant, the difference between the initial concentration of the dispersant and the equilibrium concentration is used as a calculation standard.

After the fine talc dispersant adsorption isotherm is determined, the coating needs to be prepared. The coating preparation can be carried out in an aqueous coating of a styrene-acrylic emulsion, and the coating is prepared by adding fine talc. The coating preparation process is as follows:
(1) The parameters of the styrene-acrylic emulsion are as follows: mass 25 g, solid content 48.3%, a film-forming auxiliary agent is added thereto, the content of the film-forming auxiliary agent is 10%, and the mixture is stirred to uniformly mix the two;

(2) The quality of the fine talcum powder is as follows: 0.2g, 0.6g, 1g, and respectively added to 10mL of deionized water, followed by adding a dispersing agent, ultrasonically dispersed, the dispersion time is 30min;

(3) The final step is to add the auxiliaries to the styrene-acrylic emulsion and deionized water, and uniformly stir them to obtain the prepared coating. After the preparation of the coating, it was applied to A3 carbon steel with a thickness of (26 ± 3) μm.

2. Dispersibility of fine talcum powder and its application in waterborne coatings

(1) Analysis of dispersibility of fine talc Powder The fine talc powder was subjected to sedimentation treatment by dispersing fine talc powder. In this process, after adding different types of dispersing agents, the sedimentation data of fine talcum powder existed. Certain differences. Among the selected dispersants, mainly dispersing agents such as FSJ-502, DA-01, S-100, etc., after adding them to fine talcum powder for sedimentation, the suspension sedimentation rate of fine talcum powder is as follows: S-100

At the same time, in the process of using FSJ-502 dispersant, the wavelength of the FSJ-502 can be grasped by the determination of the adsorption isotherm value. When the wavelength is 300~400nm, it can be used for the spectrum. The absorption is carried out to make the surface of the paint smoother and have a better visual sensory effect. Through the sedimentation treatment of fine talcum powder, when FSJ-502 dispersant is applied, its mass fraction and absorbance show a good linear relationship, which is greatly affected by the amount of ce in the process of fine talcum powder dispersion. When the ce value is 0.657 5g/L, the value of FSJ-502 reaches the saturation effect. The application of FSJ-502 in fine talcum powder makes the long chain of polymer get better stretching, forming an obvious adsorption layer, which can improve the performance level of the coating, which makes the coating in decoration. In the process, play a better effect.

(2) Analysis of performance of waterborne coatings

Fine talcum powder has been widely used in the present, and it has played a good role in the field of coatings. The addition of fine talcum powder to waterborne coatings has a large effect on its performance level. During the use of water-based paints, the coating is affected by fine talcum powder, resulting in some changes in its performance. For example, after the application of fine talcum powder, the surface dry ability and corrosion resistance of the coating will be improved to a certain extent. However, as the addition amount of fine talcum powder increases, the light transmittance and adsorption force may decrease. . The amount of fine talcum powder added has little effect on the impact resistance and flexibility of the coating. Regarding the impact of fine talc on waterborne coatings, the details are as follows:

Table 1 Effect of fine talcum powder on waterborne coatings

The application of fine talcum powder in waterborne coatings mainly affects the surface drying time, light transmittance and hardness of waterborne coatings. Therefore, in the application of fine talcum powder in water-based paints, it is necessary to pay attention to the effective control of the amount of fine talcum powder, so that it can better improve the performance of water-based paints to ensure that water-based paints play better in decoration. The role.

3, the conclusion

Based on the above analysis, with the rapid development of the decorative industry, its application requirements for coatings are constantly improving, and the dispersion of fine talcum powder is studied to make it better applied in waterborne coatings, for improving the decorative level and coating performance level. , played a vital role. In this process, it is necessary to grasp the dispersibility of the fine talcum powder, and consider how the effect of the fine talc powder on the surface dry time, light transmittance, hardness, flexibility, and impact resistance of the water-based paint, thereby In the application of water-based paints, it can be treated more specifically to achieve the effect of fine talcum powder. In addition, in the application process of fine talcum powder, it is necessary to pay attention to the choice of dispersant to ensure the dispersion effect of fine talcum powder, and create favorable conditions for its application in waterborne coatings.