Weigh 12g of Na2CO3 into the reaction flask and dissolve it with 200g of water for stirring, add 200g of ammonia with a concentration of 20% and put the reaction flask into a water bath to raise the temperature to 50°C; weigh 1g of additive and dilute it with 20g of water and add 50% to the reaction flask; weigh 100g of monobutyltin trichloride liquid into a constant pressure funnel and add it slowly dropwise into the reaction flask, then thermostat the reaction for 2h. Add 20% of the diluted additive every 30 minutes. After the reaction, the monobutyltin oxide was filtered through a cloth funnel, and the filter cake was transferred to a 500Ml beaker and washed with about 200ml of water, and the washing temperature was controlled at 50-60°C. The filter cake was dried with a rotary evaporator at 70-80°C. The final product was 70.78g of monobutyltin oxide with a yield of 99.1%. The assay indexes were as follows: Sn: 55.56%; Cl: 0.41%; purity: 99.2%.
Silicone oil is resistant to ultraviolet radiation and other radiation, ozonation, and has stability against climate change, making it one of the materials with the best weather resistance. Because it can penetrate into the paint surface, adding a proper amount of silicone oil and other organopolysiloxanes to the paint can extend the service life of the paint.
Polyether modified methyl silicone oil
The chemical structure of polyether-modified methyl silicone oil mainly includes graft type (Ⅰ, Ⅱ) and block type (Ⅲ, Ⅳ). Among them, type Ⅰ and Ⅲ polyether-modified polysiloxane are passed through =Si- O-C=bonding, type II and IV polyether modified polysiloxanes are bonded through =Si-C=. Its chemical structure is: Type Ⅰ and Type Ⅲ silicone oil is =Si-O-C = structurally modified silicone oil, and its hydrolytic stability is poor; Type Ⅱ, N type silicone oil is =Si-C = structurally modified silicone oil, which is stable in hydrolysis The performance is good and the application is more extensive, but the cost is much higher.
The properties of polyether-modified silicone oil vary with the changes of 4 different chain links (m, n, a, b), so the polyether-modified silicone oil with different chemical structures can be prepared by adjusting m, n, a, and b to make It is suitable for coating performance requirements.
In order to balance the performance of polyether modified silicone oil, paraffin emulsion formulation sometimes other hydrocarbon groups such as long-chain alkyl groups or phenyl groups can be introduced into the silicone chain links. In the above formulas, R is -H, -Ac, CHs, -CaH, etc., which can be selected according to needs during use.
The ratio of polydimethylsiloxane chain link to polyether chain link has a great influence on performance. Generally, the larger the dimethyl silicone chain segment, the higher the surface activity of the polyether modified silicone oil, but the worse the compatibility with the paint base and polar solvents. The larger the polyether chain segment, the better the water solubility of the silicone oil and the worse the surface activity. The a and h in the composition of the polyether chain also have a balance between hydrophilicity and hydrophobicity, because a CH(Me) CHzO chain is more hydrophobic than a CH2CH2O- chain. In order to maintain surface activity, it is generally controlled at b/(a+b)=0.2~0.8. That is, when b/(a+b) <0.2, the hydrophobicity is strong, and the hydrophilic-lipophilic balance value (HLB value) is small; when b/(a + b) ≥ 0.8, the hydrophilicity is strong, and the HLB value is large.
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