Usually the self-combustion temperature of VOCs is high, through the activation of catalysts, the activation energy of VOCs combustion can be reduced, thus lowering the starting combustion temperature, reducing energy consumption and saving costs.
Generally (without catalyst), the combustion temperature is above 600℃, and such combustion will produce nitrogen oxides, which is often referred to as NOx, and this is a pollutant to be strictly controlled. Catalytic combustion is the combustion without open flame, generally below 350℃, no NOx will be generated, so it is safer and more environmental friendly.
Polydimethylsiloxane modified reactive polyacrylate products include BYK-3700, Tego-2500, Tego-2700.
The main types of polysiloxanes used as slip-increasing and anti-scratch agents are described above. When using them, they should be used according to needs, through experiments, and choose the smallest amount of use that achieves the effect.
The surface coating film wants to obtain the additives used for slippage, scratch resistance and anti-blocking properties, so it only needs to be added to the surface coating. The author believes that due to the migration of polysiloxane slip agents, a uniform monomolecular layer with reduced surface tension is formed on the surface of the coating film. The surface of the coating film covered by polysiloxanes can be recoated, but it is also possible to form a double layer at the interface, which affects the adhesion between the layers, especially when the amount of polysiloxanes is large, it will obviously cause the coating layer Adhesion between the drops. If recoating is necessary, the surface of the coating film needs to be thoroughly polished with sandpaper to remove the polysiloxane additives before recoating. Therefore, the author believes that polysiloxane slip agents are not recommended for use in intermediate coatings and primers.
Some scholars believe that as long as the optimal use amount is selected, the adhesion between layers will not be adversely affected, because after the addition of polysiloxanes, it will migrate to hard paraffin wax the surface of the coating film during the curing process of the coating film, except for containing reactive functionalities. Except for the base polysiloxane, it will not participate in the curing reaction. Film surface. The author believes that this kind of re-migration is possible, but the degree of migration and the difference between local and overall migration in the coating film are unknowable.
Using the above three types of slip agents, in addition to gaining slippage, anti-scratch and anti-blocking properties, the coating film also simultaneously obtains many properties such as wear resistance, leveling, increased hardness and pollution resistance.
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