Today's KNOWLEDGE Share: RHEOLOGY

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Today's KNOWLEDGE Share:

RHEOLOGY

After many years in Polymer Science, I have to say that Dynamic Rheology is probably one of the most powerful tools out there !



It uses 1 or 2 grams of sample and gives you a tremendous insight in both processing/flow aspects or more fundamental molecular structure of your polymer.


Once you understand the basic concept of the produced output signals (essentially in-phase and 90° out of phase response), it will deliver its incredible power to describe the polymer melt.


The tool is also the absolute best to study thermal degradation vs. time or temperature.

It allows you to access the polymer relaxation spectrum, assess the degree of branching/crosslinking, predict weldline strength through re-entanglement time, study flow induced crystallization or gelification, etc. etc.

The comparison with steady shear or Capillary data and the applicability (or not) of the COX-MERZ rule will also highlight very important aspects of your sample micro-structure.

Yield stress of Bingham fluid can be observed also.


Don't underestimate this incredible technique to help you solve many polymer related issues.


Source:Vito Leo

Visit MY BLOG http://polymerguru.blogspot.com


#plastics #polymerscience #plasticinjectionmolding #rheology #thermal

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