Expressions for the optical anisotropy Dgr;Ggr; of Kuhn's random link (an equivalent to the stresshyphen;optical coefficient) of stereohyphen;irregular and multirepeat polymers are derived on the basis of the additivity principle of bond polarizabilities and the rotationalhyphen;isomerichyphen;state approximation for rotations about skeletal bonds. By multirepeat polymers we mean ones in which a stereochemically identical structure repeats along the chain at an interval of an arbitrary number of skeletal bonds. Expressions for the unperturbed meanhyphen;square endhyphen;tohyphen;end distance lang;r2rang;, which are required in the calculation of Dgr;Ggr;, are also obtained. All expressions are cast into compact form by use of Flory and Jernigan's method. Comparison is made of expressions for rang;r2rang; derived in this paper, with those given previously by Flory and his cohyphen;workers and by the present author.
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