Reasons for Using Surface Modifiers

With the notable exception of carbon blacks, the natural surfaces of most particulate fillers are less than optimum for dispersion into, and interaction with, polymers. Surface modifiers can frequently improve this, and other filler properties. Sometimes materials which are effective surface modifiers will be found to have been added for filler manufacturing reasons. The main reasons for finding surface modifiers present are  

It should also be noted that the presence of surface modifiers can also influence other properties. This includes properties such as bulk density, powder flow and dustiness. They can also have unexpected effects on properties such as thermal stability, fire retardancy and ageing. These effects may be positive or negative. 

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