The application of gas-phase white carbon black in coatings requires scientific process control to achieve its functionality.
1、 Distributed process control
1. Equipment selection
① Low viscosity coating systems (such as solvent based paints) use high-speed shear dispersers to ensure uniform dispersion of nanoparticles;
② High viscosity systems (such as silicone resin coatings) require strong shearing using a kneading machine or an open mill to avoid agglomeration;
③ Three dimensional high-speed dispersion or grinding equipment is recommended for powder coatings.
2. Distributed parameter optimization
① Control the speed range, type of mixing blade, and equipped with a cooling system to prevent local overheating leading to gel;
② The dispersion time needs to balance efficiency and stability, avoiding excessive shear damage to the hydrogen bond network.
2、 Functional application methods
1. Rheological regulation
① As a thixotropic agent, unmodified hydrophilic products (such as HL-200) form a hydrogen bond network through surface silanol groups:
② Thickening and anti settling during static state (such as pigment anti settling), reducing viscosity under dynamic shear to improve workability;
③ Adding 1.8% to acrylic paint can significantly improve its anti sagging performance (275 μ m coating does not sag).
2. Performance enhancement modification
1. Hydrophobic products (such as HB-139):
① Add 0.8% to the epoxy system to simultaneously optimize the anti sagging properties and coating glossiness; Improve coating hardness, scratch resistance, and chemical corrosion resistance.
2. Transparent system application:
Control the amount of addition (usually 0.5% -2.0%) to adjust the matte effect and avoid affecting the light transmittance.
3、 Special system adaptation
1. Water based coatings: Surface modified products should be selected to solve the problem of shrinkage caused by high surface tension and improve flowability;
2. High solid content coatings (such as ship paint): prevent vertical surface sagging through thixotropy while ensuring storage stability.
4、 Application key points
Before adding, it is recommended to pre disperse the white carbon black in the solvent or resin base material to avoid direct powder addition, which may cause difficulty in dispersion; Hydrophobic products are more suitable for systems with high water resistance requirements, while hydrophilic products are more suitable for polar solvent systems. The specific addition ratio needs to be determined through rheological curve testing according to the coating formula to balance workability and final film performance.