Are Kuhn Lengths Determined by the Number of Bonds?

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SUMMARY

Kuhn lengths are not fixed but depend on the number of bonds in a polymer chain. In the discussion, specific values are provided: 18 bonds for polyethylene and 24 bonds for poly(cis-isoprene), with Kuhn lengths of 12 Å and 9 Å, respectively. The formula for Kuhn length, h = nL and <h²> = nL², indicates that Kuhn lengths vary based on the chosen number of bonds 'n'. Therefore, the assertion that Kuhn lengths are fixed is incorrect.

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chemie
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Okay so I know that they aren't but this thing i am reading makes it appear that they are fixed.
QUOTE from the text:

"The values of nb(for the statistical segment) chosen in this work are 18 bonds for
polyethylene and 24 bonds (a hexamer) for poly(cisisoprene).
One reason for these choices of nb involves the concept of the Kuhn statistical length, which, for polyethylene is ,12A°and ,9 A° for poly(cis-isoprene)".

So is he trying to say that Kuhn lenghts are fixed?

I don't understand. because kuhn lenghts follow this formula: ,h=nL and <h^2>=nL^2 ...which means it depends on the number of bonds 'n' that we chose to work with in the first place.
 
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well i was wrong they are indeed fixed.
 

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