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Intrinsic viscosity of a polymer and its density

  1. Jul 23, 2014 #1
    Hello Forum,

    I have two polymers (both in pellet form). Their spec sheet shows that the two polymers have different intrinsic viscosity IV. There are so many definitions of viscosity (dynamic, intrinsic, inherent, etc.)

    In general viscosity and density are two independent properties of a fluid. Surely most common substances that have high viscosity also have high density.Regardless, it seems that the two properties are not connected. One example: Some motor oil is more viscous than water but less
    dense than water.

    As far as IV (intrinsic viscosity): http://en.wikipedia.org/wiki/Intrinsic_viscosity
    it is defined as s a measure of a solute's contribution to the viscosity of a solution...

    I would like to understand if the polymer rated with larger IV also has a higher density than the other one. I am simply melting the polymers and not putting them into a solution with a solvent...

  2. jcsd
  3. Jul 25, 2014 #2
    Higher iv correlates with higher molecular weight. This them correlates with higher melt viscosity. Iv is usually used to compare molecular weights for the same polymer.

  4. Jul 26, 2014 #3
    Thank you Chet
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