Premium
The β Phase Formation Limit in Two Poly(9,9‐di‐ n ‐octylfluorene) based Copolymers
Author(s) -
Bright Daniel W.,
Moss Kathryn C.,
Kamtekar Kiran T.,
Bryce Martin R.,
Monkman Andrew P.
Publication year - 2011
Publication title -
macromolecular rapid communications
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.348
H-Index - 154
eISSN - 1521-3927
pISSN - 1022-1336
DOI - 10.1002/marc.201100221
Subject(s) - copolymer , polymer chemistry , materials science , polymer science , limit (mathematics) , phase (matter) , polymer , chemistry , organic chemistry , composite material , mathematics , mathematical analysis
Random copolymers of poly(9,9‐di‐ n ‐octylfluorene) (PF8) incorporating 0, 8, 12, 15, and 20% dibenzothiophene (DBT), and copolymers with 2, 5, 8, 12, and 15% dibenzothiophene‐S,S‐dioxide (S‐unit) were synthesised. Absorption and emission spectra of thin films indicate that the DBT system shows a linear decrease of toluene vapour induced β phase with increasing DBT content to a 20% cutoff, whilst in the S‐unit copolymers the β phase is present up to 12% co‐monomer content, and at 15% the characteristic absorption peak is absent or masked. These results demonstrate the limits, in thin films, at which the β phase can be formed in widely used PF8 copolymer systems for device applications and clearly show that it is practical to use copolymers having electron or hole transport units in the polyfluorene backbone and still be able to form efficient β phase emission sites.