in polymers

The ratio of the mean-square end-to-end distance,
, of a linear polymer chain in a theta state to
, where is the number of rigid sections in the main chain, each of length ; if all of the rigid sections are not of equal length, the mean-square value of is used, i.e.
In simple single-strand chains, the bonds are taken as the rigid sections. The recommended
symbol is: ( when
).

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