|
|||||
|
|
An effect of side chain length on the solution structure of poly(9,9-dialkylfluorene)s in toluene |
|
| Authors: | M. Knaapila,L. Almá sy,M.L. Ramos,F. Galbrecht,U. Scherf,A.P. Monkman |
| Affiliation: | a MAX-lab, Lund University, POB 118, SE-22100 Lund, Sweden b Research Institute for Solid State Physics and Optics, POB 49, Budapest-1525, Hungary c GKSS Research Centre, Max-Planck-Strasse 1, D-21502 Geesthacht, Germany d Departamento de Química, Universidade de Coimbra, P-3004-535 Coimbra, Portugal e Fachbereich Chemie, Bergische Universität Wuppertal, Gauß-Strasse 20, D-42097 Wuppertal, Germany f Department of Physics, University of Durham, South Road, DH1 3LE Durham, UK |
| Abstract: | 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 (∼1 nm) and poly(9,9-dihexylfluorene) thin (∼1 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. |
| Keywords: | Conjugated polymers Polyfluorene Solutions |
| 本文献已被 ScienceDirect 等数据库收录！ | |