Methods of Using Surface Modifiers

Modification of the surface of fillers may be brought about in a variety of ways. The most appropriate will depend on many factors, including the nature of the filler and the process used in producing it, the nature of the additive, and of the polymer and the composite processing conditions. 

Usually requires an expensive additional step, but is claimed to give more efficient use of the additive. Usually less expensive, but may require higher additive levels. 

Volatile by-products such as alcohols are easily dealt with. Volatile by-products can be a problem. 

Essential where improved filler processing and stability are sought.  

Surface reaction and coverage can be strictly controlled. Interference from other compounding additives can be minimised. Surface reaction is very much at the mercy of processing conditions, including competition from other additives. Residual, unreacted, additive more likely to be present and may cause problems. 

---