in polymers

A hypothetical linear macromolecule consisting of an infinitely thin chain of continuous curvature; the direction of
curvature at any point is random. The model describes the whole spectrum of chains
with different degrees of chain stiffness from rigid rods to random coils, and is
particularly useful for representing stiff chains. In the literature this chain is
sometimes referred to as a Porod–Kratky chain. Synonymous with continuously curved
chain.

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