We present guidelines on how the solution structure of pi -conjugated hairy-rod polyfluorenes is controlled by the side-chain length and branching. First, the semiquantitative mean-field theory is formulated to predict the phase behavior of the system as a function of side-chain beads (N). The phase transition at N=N{ *} separates a lyotropic phase with solvent coexistence (NN{ *}). The membrane phase transforms into the isotropic phase of dissolved rodlike polymers at the temperature T_{mem}{ *}(N), which decreases both with N and with the degree of side-chain branching. This picture is complemented by polymer demixing with the transition temperature T_{IN}{ *}(N), which decreases with N . For NN{ *}, stable membranes are predicted for T_{IN}{ *}N{ *}. T_{mem}{ *}(N) decreases from 340 K to 280 K for N > or = 8 . For copolymers, the membrane phase is found when the fraction of F8 units is at least 90%, T_{mem}{ *} decreasing with this fraction. The membrane phase contains three material types: loose sheets of two polymer layers, a better packed beta phase, and dissolved polymer. For N > or = 7 and T

Structure and phase equilibria of polyelectrolytic hairy-rod supramolecules in the melt state Knaapila, M; Stepanyan, R; Horsburgh, LE; Monkman, AP; Serimaa, R; Ikkala, O; Subbotin, A; Torkkeli, M; ten Brinke, G; Horsburgh, Lockhart E. Take-down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.Downloaded from the University of Groningen/UMCG research database (Pure): http://www.rug.nl/research/portal. For technical reasons the number of authors shown on this cover page is limited to 10 maximum. FIN-02015 HUT, Finland ReceiVed: June 25, 2003; In Final Form: September 29, 2003 The structure formation and phase behavior of supramolecular hairy-rod polymers consisting of rodlike polymer chains with physically bonded side chains are investigated in the melt state using small-angle X-ray scattering. The supramolecules consist of poly(2,5-pyridinediyl), complexed by methanesulfonic acid to form poly(2,5-pyridinium methane sulfonates), to which octyl gallates are hydrogen bonded. These comblike supramolecules self-organize in rodlike assemblies in a square or oblique lattice or form lamellar structures. Moreover, nematic (solid) and macrophase separated structures are observed. These results are collected in a phase diagram in the high polymer fraction limit and they are in a clear qualitative resemblance with recent theoretical modeling. The differences and similarities between the experiments and theory are discussed.