%0 Artikel
%@ 0032-3861
%A Knaapila, M.
%A  Almasy, L.
%A  Haramus, V.M.
%A  Ramos, M.L.
%A  Justino, L.L.G.
%A  Scherf, U.
%A  Burrows, H.D.
%A  Monkman, A.P.

%D 2008
%J Polymer
%N 1377
%P 2033 - 2038 
%R doi:10.1016/j.polymer.2008.02.046
%T An effect of side chain length on the solution structure of poly(9,9-dialkylfluorene)s in toluene
%U http://dx.doi.org/10.1016/j.polymer.2008.02.046
8 
%X The effect of side chain length of π-conjugated poly(9,9-dialkylfluorene)s has been studied in semi-dilute (10 mg/mL) toluene solutions using small-angle neutron scattering (SANS) and 1H and 2H NMR spectroscopies. Under these conditions, SANS data indicate that poly(9,9-dinonylfluorene) and poly(9,9-dioctylfluorene) are dissolved down to the molecule level and appear as elongated one-dimensional chains (length >20–30 nm). In contrast, the shorter side chain polymers exhibit a self-association so that poly(9,9-diheptylfluorene) forms thin sheet-like (not, vert, similar1 nm) and poly(9,9-dihexylfluorene) thin (not, vert, similar1 nm) and thick sheet-like (>6 nm) aggregates. 1H NMR data, together with the density functional theory (DFT) calculations, however, show that this occurs without changes in the conformation of the polymer backbone.