Do universal purging compounds work with all applications and polymers?

Thermoplastic processing is done in many different ways with many different polymers, within a wide range of processing temperatures. Universal purging compounds are available on the market, and they do provide benefit in very limited applications. However, universal purging compounds are compromised solutions, and are not the best solution for the majority of operations. Universal purging compounds are effective only on polymers compatible with their matrix and MFI and less effective on incompatible polymers and/ or with very different matrices. When transitioning between two incompatible polymers, two differing MFI ranges, or two different matrices, it is best to use a specialized purge compound.