Intrinsic symmetry of the AABb-type distribution

By taking an AaBb‐type polymerisation as an example Each unit has a functional groups of type A and b of type B. , an intrinsic symmetry of the equilibrium number fraction distribution of species is revealed. The symmetry shows that the distribution is invariant under transformation between the variables which describe the total system and the variables which describe the sol. It results that, when the polymer quantities for the pre‐gel regime are given, the corresponding quantities for the post‐gel regime can easily be obtained. As an illustration, the k th radius of an AaBb‐type polymerisation is discussed.