Kuhn length

The Kuhn length is a theoretical treatment, developed by Werner Kuhn, in which a real polymer chain is considered as a collection of ${\displaystyle N}$ Kuhn segments each with a Kuhn length ${\displaystyle b}$. Each Kuhn segment can be thought of as if they are freely jointed with each other. Each segment in a freely jointed chain can randomly orient in any direction without the influence of any forces, independent of the directions taken by other segments. Instead of considering a real chain consisting of ${\displaystyle n}$ bonds and with fixed bond angles, torsion angles, and bond lengths, Kuhn considered an equivalent ideal chain with ${\displaystyle N}$ connected segments, now called Kuhn segments, that can orient in any random direction.

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