(53g) Phase Behavior of Pyrene and Vinyl Polymers with Aromatic Side Groups

We investigated phase behavior and thermodynamic properties of binary mixtures of pyrene and vinyl polymers with aromatic side groups using differential scanning calorimetry to understand the effects of π-π interactions in the mixtures of polymers and polycyclic aromatic hydrocarbons (PAHs), chemical motifs widely used for functional materials and abundant in nature. By employing the melting points of pyrene crystals in polymer, we constructed the phase diagrams of binary mixtures of pyrene and five polymers with different side groups. Using the phase boundary points, we extracted the effective interaction parameters between pyrene and the polymers and the pyrene compatibility increases increase with the magnitude of the dipole moment of side groups. We also extracted the composition of polymer-rich phases using the glass transition temperatures of the mixtures. We found that the stability limit is very important in the control of phase compositions, and thus proper processing including the consideration of the stability limit of the mixtures is mandatory to obtain target compositions of phase separated domains.