Poly (phthalates glycol) esters are carbon-black ultra-dispersants in solventized chains (2)

2 Results and discussion of the effect of the relative molecular mass of
2. 1 PAEG on dispersion performance
Polyester chain length has a greater effect on the dispersion effect of synthetic ultra-dispersants, mainly reflected in the fineness of the coating after the ingredients are ground and the viscosity of the coating.
2. 1. 1 Effect of relative molecular mass on coating fineness
The dispersion fineness of carbon black particles determines the coloring force, transparency and stability of the coating. Fine particles through the large, paint coloring force reduced, stability is poor, fine through the low, transparency increased, stability is also better, but the coating system and production costs have put forward higher requirements, generally 10 to 15 m is appropriate. Figure 2 shows the effect of the relative molecular mass of PAEG on coating fineness.
As can be seen from Figure 2, when the relative molecular mass of PAEG super-dispersant is 1,000, compared to the blank sample, the fineness of the coating has decreased significantly, but they are greater than 15 m (byK163 corresponding to the standard value), indicating that the super-dispersant has a certain dispersion capacity, but the dispersion effect is not ideal; Degrees are close to the dispersion effect of BYK163, and are not higher than the fineness value of BYK163, reflecting a good dispersion effect, when the relative molecular mass reached 3,000 and 4,000, the fineness of the coating does not drop back up, which may be due to the long solvent chain between the chain of chains, which in turn causes pigment particles to appear a certain degree of "bridge" flocculation.. 2. 1. 2 Effect of relative molecular mass on coating viscosity
the relative molecular mass of PAEG on coating viscosity is shown in Figure 3.From Figure 3, it can be seen that when the super-dispersant relative molecular mass of 1,000, the coating shows a better anti-stick effect, but compared with BYK163, there is a significant gap; The ability to reduce adhesion even exceeds BYK163, but when the relative molecular mass is 3,000 and 4,000, the effect of the coating is greatly reduced, and even samples with a relative molecular mass of 4,000 have little adhesion, which further proves the hypothesis that too long solventization chains may have inter-molecular tangles.
, the relative molecular quality of solventized chain polyester (phthalates glycol) esters in this experiment was preferably 2,000.
2. 2 Effects of different anchoring groups on coating performance
The formation of a strong combination of anchoring groups in ultra-dispersant structures and pigment particle surfaces is critical to the selection of anchoring groups for pigments of different structures. The correct anchoring group-pigment combination avoids the "re-coarseness" of dispersed pigment particles, while also providing excellent color and gloss for cured paint film. In this paper, the selection of ultra-dispersant anchoring group is evaluated from the angle of paint film color and gloss.
According to the grinding effect, paEG with a relative molecular mass of 2,000 was selected as the solventized chain, and N, N-methylamine, N-methylamine, N-methylethanolamine, polyethylene subamine, polyethylene polyamine were selected for end-based change, obtaining a series of ultra-dispersant PAEG-1, PAEG-2, PAEG-3 and PAEG-4. According to GB/T 11186. 2 - 1989 method to determine the paint film phase, the results can be seen in Table 1.as can be seen from Table 1, compared to the blank sample, the color fastness of the paint film has been improved to varying degrees compared to the blank sample, where the color fastness of THEG-3 is the best, even better than BYK163; The same trend is found in the yellow-green phase, where the effects of PAEG-2 and PAEG-3 are close to BYK163, and chroma e also indicates that PAEG-3 has a performance closer to the standard sample in 4 samples..