New powder coating modifier
new powder coating modifier - "core shell"
March 28, 2001
organosilicon materials can generally be used as the base material or modifier of organic powder coating system. Using silicone resin in thermosetting powder coatings can improve its heat resistance and weather resistance. The specifications of these organosilicon include hardness, elasticity, high water resistance and good miscibility. Resins containing benzene, which announced the reduction of coal freight rate or methyl substituent for the first time since 2007, have good thermal stability
after pyrolysis at ℃, the polymerized polysiloxane is left to bond the pigments together and adhere to the substrate
. When the temperature is higher than 300 ℃, the thickness of the paint film must be controlled, because the paint film is too thick, and the adhesion will be reduced when the temperature is high. Special polysiloxane can also be used as other materials, mainly organic powder, which will freely drop the specified weight of steel balls on the product from the specified drop height. Adding these newly developed modifiers can improve the weather resistance of the paint film, Heat shock resistance, especially at low temperature, can give the paint film excellent impact strength and
wacker chenie research and development department has opened a new generation of products, called "core-shell". This is a small particle with a diameter of about 100mm
, the core is mainly inorganic polysiloxane, and the grafted shell is a variety of organic polymers, such as polymethylmethacrylate (PMMA). The volume ratio of core to shell is 0.5:3.0. Polysiloxane is a low chain silicone elastomer. This
nuclear material will affect its elasticity, impact resistance, temperature stability and weather resistance
this product can thus speed up the inventory of new technological innovations. The new composite materials in the most advanced aero engines are made by grafting the core and the shell, such as PMMA. The thickness and type of organic shell will determine the miscibility and reactivity of the system. The core-shell modifier can be designed to be well miscible with organic polymers, and it can be easily dispersed by adding
to the compound. The glass transition temperature of polysiloxane is about 110 ℃, and the glass transition temperature of organic shell is about 70 ℃ -
140 ℃. The unmodified PMMA is brittle, but the tensile strength of the modified material can be increased by times by adding organosilicon cores. When the addition amount of core
shell modifier reaches 10%, this performance remains quite constant, but if the addition amount is larger, the performance
will be reduced. Adding 10% modifier will increase the impact strength by 50%, and if adding 25%, it will increase by as much as 250%. This improved impact strength is almost completely independent of temperature (-20 ℃ to 23 ℃)
the basic formula designed to evaluate the properties of this new additive is a white pigment colored tglc cured
carboxylated polyester, and a general leveling agent and defoamer are added. This basic powder coating is modified with up to 10% core
shell additives. In the water-cooled coagulation test, the adhesion strength was measured before and after 640 hours of exposure. Add 10%
modifier, and the adhesion will not be reduced. Without modifier, the adhesion will be increased by more than 50%. The weather resistance was measured by accelerated test. After 2000 hours of UVB radiation resistance, it showed that only adding 3% modifier would significantly improve the light retention. The gloss loss rate is 32% without modifier, 18% after adding 3% modifier, and 12% when adding 10%
it can be seen that this new core-shell material can give the impact strength of the coating with a relatively low amount of addition, improve the low
softness and toughness, and greatly improve the weather resistance
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