Solubilities and polymer-solvent-nonsolvent θ-compositions of poly (di-n-alkyl itaconates)

In order to establish the prerequisites for the examination of solution properties of poly(di-n-alkyl itaconates), the solubilities of the first 11 members of this polymer homologous series were determined in 70 solvents, and the results correlated with the lengths of the ester substituents of the polymer chain, the solvent solubility parameters and the solvent hydrogen bonding capacities. The relation between solvent strength and the lengths of ester substituents of the monomer units was established quantitatively for several solvents in terms of φ_{2 crit.,} the nonsolvent volume fraction in ternary polymer-solvent-nonsolvent θ-mixtures, and evaluated according to a turbidometric titration method proposed by ELIAS ¹. Both groups of results are a guideline for the probable existance of θ-conditions for particular polymer-solvent pairs and permit the prediction of solubilities of still higher members of the series.