What is silicone?
Silicone, the scientific name is generally called silicone, polysiloxane, silicone powder used in the market is generally produced from higher molecular weight silicone plus silica, is the silicone dispersion to silica, low molecular weight silicone is generally liquid, we commonly known as silicone oil. However, if the molecular weight is large enough, it can be made into a flaky solid.
Silicone powder and silicone masterbatch
What is silicone masterbatch? What is silicone powder? The distinction is actually quite simple. Ultra-high molar mass of polysiloxane uniformly dispersed in particles or loaded on the surface of silica powder, the former is called silicone masterbatch, while the latter is called silicone powder.
General silicone powder to silicone content of more and less to distinguish the classification, if your silicone powder in the silicone content is 40%, that is, silicone powder should be 40% silicone (silicone oil) + 60% silica and other additives (such as coupling agents, etc.), if the silicone content is relatively high, it is best to make the master batch first, because the intermolecular force of silicone is strong, not easy to disperse uniformly through physical methods, the need for strong shear to complete. The higher the silicone content in silicone powder, the greater the viscosity of the material, the less easy to disperse when used in plastics. Silicone content and high molecular weight can be used as a wear-resistant agent, but then its lubricating properties on the contrary, the mechanism of lubrication is that the coefficient of friction between silicone and silicone is small, silicone stable average dispersion to the system to have this phenomenon, if the system are not dispersed, it is not good to talk about lubrication.
The so-called silicone masterbatch, that is, after dilution of silicone (generally or silicone + silica) and then 50%-30% of the carrier and other additives, the carrier is generally polyolefin, can be added directly as inorganic filler wetting agent use.
Silicone masterbatch application in plastics has excellent performance.
1、Improve plastic processing fluidity and mold release. Reduce torque, reduce equipment wear, easy mold filling, reduce product defective rate.
2、Significantly reduce the coefficient of friction, improve the smoothness, improve the surface gloss, enhance the surface silk touch, and improve the scratch resistance.
3、Improve flame retardancy, reduce smoke density, improve the impact strength and surface gloss of flame retardant materials (high filling).
4、Have good stability and non-migration.
5、Silicone masterbatch is safe to use, easy to mix, stable in performance, and easy to disperse in resin.
6、Different additive amounts have a direct impact on the performance, which is generally shown as follows: when the additive amount is low, it will improve the fluidity and internal smoothness of the plastic, and molding is easier. When the addition amount is high, it will improve the surface properties of the material, including reducing the friction coefficient and giving glossiness to the surface.
In some special areas, silicone masterbatch has good use effect.
1、In the halogen-free flame retardant wire and cable materials, it can significantly improve the scratch resistance and prevent the frost spraying phenomenon.
2、In the automotive PP composite material, it can significantly improve the scratch resistance and surface gloss of the material.