Will inorganic coatings replace organic coatings in the future? Experimental proof!

0 Introduction: With the
development of industrialization, the earth's environment has been seriously damaged, and serious pollution threatens people's living space. "Green" and "environmental protection" are the requirements that people attach great importance to the coating industry after environmental protection, and are also the future development direction of the coating industry. Compared with organic coatings, inorganic coatings are taken directly from the rich minerals in nature, and the production and use of their substations are fully compliant with the requirements of energy conservation and emission reduction, and the vast majority of organic coatings with the same cost are difficult to achieve the technical indicators .
In recent years, the domestic construction industry market due to the national underground confined space with fire prevention, non-combustible interior wall paint mandatory requirements, promote the development of inorance interior wall paint, the major domestic architectural coating manufacturers are in the research and development of inorance building coatings, and constantly introduce their own new products, so that inororated silicate coatings in China to find a rare opportunity for development.
Inorganic coatings have better outdoor weather resistance and adhesion, but their resistance to contamination on its service life is equally important, on the preparation of inorganic coatings have more literature for reference, for organic coatings resistant to soiling research literature is also more. However, there are few reports in China on the influence factors of the resistance of inororable coatings to contamination.
experts, through the particle size of potassium silicate and silicone sol compound solution, explore the basis of the stability of potassium silicate and silicon sol mixing, and silicate coating breathability is one of its strengths, but porous surface will inevitably lead to a higher water absorption rate of the coating, resulting in dust ash easy to collect into the paint film when doing contamination testing, difficult to rinse down. Because of the special structure of silicate and silicone sol, there is a big difference with acrylic emulsion, and the structure of its resistance to contamination will not be exactly the same.
this paper analyzes the influence of silicate content, silicone sol content, powder structure and additives in the formulation to explore how to achieve high soil resistance inorderable coatings.
1 Experimental part
1.1 Experimental raw material potassium silicate (AH-K1: module 3.75 to 4.15, silica content >16%): Aussie; potassium silicate (GHSK: module 4.09, silica content 2 0.63%): Allianz; Stable potassium silicate (MOS-1010: module 3.6, silica content 16% to 18%): Peito; silicone sol (MOS-2012): Platinum Inte; PHEN emulsion (6516-2): Changxing; Pure propylene emulsion (7016G): BASF; PHEN emulsion (791ap): BASF; PHEN emulsion (296ds): Platinum Inte; PHEN emulsion (559ap): BASF; PHEN emulsion (R64): Dow; Season ammonium salt stabilizer (SPS): Clariant; Silicone hydrophobic (BS1306): WACKER; Teflon wax powder (TF1778): Lu Borun; Sulphite titanium white (R996): Sichuan Longyu; 800 microfluorite: Guangdong Yufeng. ;1000-eye heavy calcium (GF110): Guangfu; 800-eye talcum powder (CMS-666): Liaohua; 1250-eye wet mould mica (GA-4): Sharp.
1.2 High-speed dispersion machine (GFJ-0.4): Shanghai Modern Environmental Engineering Technology Co., Ltd.;
1.3 Coating preparation and performance test 1.3.1 inorganic bonding substances and emulsion compatible test selected calcium ion stability is more excellent several emulsion products, with the alternative two potassium silicate compatible test, according to emulsion: stabilizer: potassium silicate: 9:1:22 ratio mix, to observe whether there is a break or flocculation phenomenon. 1.3.2 The preparation of experimental formulations for inorgeable coating samples is available in Table 1.
1.3.3 Inorger exterior coating preparation process (1) premixed: add water to the dispersion cylinder, add additives, 300 to 500r/min mix to form a gel-like substance; Pulp grinding 20 to 25 min to less than 60 m fine; (3) add phenylpropyl emulsion and seasonal ammonium salt stabilizer to the dispersion tank, 800 to 1200r/min mix evenly, (4) add potassium silicate solution and the remaining water in turn in the dispersion cylinder, 800 to 1200r/min mixed evenly, that is. 1.3.4 Performance test method in accordance with JG/T26-2002 "external wall inorgeable building coating", respectively, test thermal storage stability, viscosity, ratio, low temperature storage stability, water resistance, alkaline resistance, drying time, scrub resistance, temperature change resistance, aging resistance, soil resistance, coating appearance and so on. The soil resistance test method is carried out according to appendix A method in JG/T26-2002, using coal ash as the pollution medium, and the change of paint film reflectivity before and after pollution is evaluated.
2 results and discussion
2.1 emulsion and silicate suitability analysis according to the method mentioned in 1.3.1, select different combinations of potassium silicate and emulsion for experiments, the experimental combination is seen in Table 2.
The first premise of exploring the resistance of inorgeable coatings is to select a stable storage product system, and then do follow-up performance testing, from Table 2 can be seen: (1) different silicate / silicone sol with different emulsion compatible will appear different performance, small editor in the verification experiment found that the combination of the two mixed with broken milk, after making paint, there will be different degrees of post-thickening and adhesion phenomenon. Therefore, the method can be used as an easy method to determine the compatible of silicate and emulsion; (2) potassium peto silicate with stable treatment is milder than other potassium silicate, emulsion is more tolerant of it, more widely adapted, and the module in a certain range of potassium Australicate due to insufficient crystal concentration, The emulsion has the lowest tolerance, the higher the corresponding requirements for the emulsion, (3) the silicone sol has better compatible with potassium silicate and various emulsions, is not easy to produce flocculation or gel phenomenon, (4) the emulsion itself is more alkaline, then the better the compatible with silicate compounding.
2.2 Silicates and emulsions with the effects on stain resistance to take Table 1 1 formulation to add different emulsion and potassium silicate combinations, other raw materials unified, preparation of sample paint, and preparation of models. The performance test methods described in 1.3.4 are used to test each performance separately.
visible from Table 3, the combination of different silicates and emulsions showed greater differences, combining the balance of performance and the optimal performance of stain resistance, the MOS1010 and 791ap were selected to carry out experiments on the formulation of 2, 3, 4, 5, and some of the resulting properties as shown in Table 4.
can be seen by the recipes in Table 4, 2, 3, 4, Contamination resistance and emulsion in the adhesive material in a larger proportion of correlation, improve the content of emulsion, reduce potassium silicate content, anti-fouling performance showed an increasing law (see Figure 1), but in order to achieve a lower organic matter content, the experiment in potassium silicate compound silicone sol and improve the use of, soil resistance will also be improved, such as the use of the method of 5 , resistance to contamination will be significantly improved.
2.3 the effect of the powder structure on stain resistance can also be seen in the data in Tables 4, 5 and 6. The proportion of heavy calcium in the formula is reduced, increase the amount of silicon micro-powder and mica powder, its resistance to contamination is also significantly improved, the reason may be that the pore rate of silicon micro-powder is low, good filling, effectively reduce the pore rate of the paint film, and the layer structure of the mica powder better provides closure, so that the paint film surface ash is easy to flush clean, and excessive addition of heavy calcium will have a negative effect on the paint film stain resistance.
2.4 Additives on the effects of stain resistance for the 5-formulation, try to improve soil resistance by adding additives, consider using WACKER silicone hydrophobic agent BS1306 to increase coating hydrophobic and Luberon TF1778 TF1778 Teflon wax powder to increase coating anti-stick properties. See table 5.
It can be seen that the simple use of silicone hydrophobic agent can not make the powder ash that has been adsorbed to the coating film washed out of the water, and Teflon wax powder because to a certain extent to reduce the adhesion of the powder ash on the surface of the paint film, improve the smoothness of the paint film, so it is beneficial to improve the resistance of inorganic paint film.
3 Conclusion
Experiments on several factors that may affect the stain resistance of inorient coatings show that loose pores on the surface of the silicate coating coating film are the main cause of poor soil resistance, while the effects of the surface energy of the lacquer coating are more limited, so improving the soil resistance of inoroculated coatings is not a simple adjustment, but needs to be adjusted from the following aspects: (1) to improve the emulsion content, reduce the pore rate; Salt and silicone sol compounding method, and improve the proportion of inormeric adhesives, reduce the pore rate; (3) by selecting silicon micro-powder and mica powder, such as a type of filling and closed performance of better powder, reduce the porosity rate; (4) supplemented by a certain amount of Teflon wax powder, help to reduce the surface energy of the paint film, improve stain resistance, through the above-mentioned comprehensive considerations, in order to make products that meet the existing standards of stain resistance.
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