Reduced sp. viscosity, light-scattering values, and Goode's J-value were detd. for mixts. of isotactic (I) and syndiotactic poly(Me methacrylate) (II) in CHCl3. Plots of these values vs. I-II ratios indicated that stereocomplexes appear not only at the 1:2 I-II ratio (shown by previous x-ray diffraction data), but also at a 2:1 I-II ratio. These 2 special interactions appear independently of the mol. wts. or tacticities of the isomers, and it is assumed that the stereocomplexes are not large structures.
vd Berg, W. B., Hijmans, B. S., Piet, P., & Heikens, D. (1968). Complex formations between iso and syndiotactic polymethyl methacrylate in solutions. Nature, 217(5132), 949. https://doi.org/10.1038/217949a0