Stannous octanoate uses

Uses: Organic synthesis, basic catalyst for the production of polyurethane foam, catalyst for room temperature curing silicone rubber, polyurethane rubber, polyurethane coating \ sealant, silicone rubber and other industries .

The thickening mechanism is that in the water phase of the latex paint, the first is that the hydrophobic end of the molecule associates with the hydrophobic structure of latex particles, surfactants, and pigments to form a three-dimensional network structure, which is also the source of high shear viscosity; the second is like a surface The active agent, when its concentration is higher than the critical micelle concentration, forms micelles, and the mid-shear viscosity (1~100s-l) is mainly dominated by it; third, the hydrophilic chain of the molecule and the water molecule act through hydrogen bonds to achieve Thickening effect.

Its characteristics are: due to low shear rate and low viscosity, it has good leveling properties and has no effect on the gloss of the coating. The high shear rate has high viscosity, so the coating film has a high degree of fullness. The molecular weight is low, and the viscosity is high at high shear rate, so the paint roller coating has good splash resistance. These aspects are generally better than alkali swelling thickeners. In addition, it has good antibacterial properties and low yield value. However, surfactants, emulsions, solvents, etc. in the formulation have a great influence on its thickening effect. If the content of the emulsion increases, the surface tension decreases and the particle size decreases, the thickening effect will increase.

Because the hydrophobic structure absorbs and associates with each other, the HLB value of any component in the system changes, and the thickening effect also changes, that is, it is very sensitive to formulation changes. However, the water, wetting agent, titanium dioxide, fillers, and wax for water-soluble solvents  in the formula have weak interaction with associative thickeners, so they have little effect on viscosity. Richey et al. 15 use fluorescent tracer pyrene associative thickening (PAT, the number average molecular weight is 30000, the weight average molecular weight is 60000), the study found that when the mass fraction is 0.02%, the micellar aggregation degree of A cry sol RM-825 and PAT is about 6; thickener and latex particle surface The association energy of PAT is about 25kJ/mol; the area occupied by each PAT thickener molecule on the surface of the latex particles is about 13nm², which is about 14 times the area occupied by Triton X-405 wetting agent 0.9nm².

Associative polyurethane thickeners such as RM-2020NPR, DSX 1550, etc.
The development of environmentally friendly associative polyurethane thickeners has received general attention. For example, BY K-425 is a urea-modified polyurethane thickener without VOC and A PEO, Rheol ate 210, Borch iGel 0434, Tego Visco Plus 3010, 3030 And 3060, etc. are all associative polyurethane thickeners that do not contain VOC and A PEO.