Alternating Copolymers of 2,6-Bis(p-dihexylaminostyryl)anthracene-9,10-diyl and N-Octylcarbazole with Large Two-Photon Cross Sections

We report the synthesis thermal one and two photon properties of poly(2 6 bis(p-dihexylaminostyryl)anthracene 9 10 diyl alt N octylcarbazole 3 6 /27 diyl) (P1/P2) The as synthesized polymers exhibit number average molecular weights of 1 7 x 10(4) for P1 and 2 1 x 10(4) g/mol for P2 They emit strong one and two photon excitation fluorescence with the peak around 502 nm and the fluorescence quantum yields around 0 76 in chloroform In film state P1 and P2 show differ ent red shift emission with the peaks at 512 nm and 523 nm respectively The DSC measurement reveals that as synthe sized polymers are all amorphous aggregates with the glass transition temperatures of 131 degrees C for P1 and 152 degrees C for P2 The solution two photon absorption (TPA) properties of P1 and P2 in chloroform are measured by the two photon induced fluo rescence method using femtosecond laser pulses (120 fs) The TPA cross sections (delta) are measured over the range of 700-900 nm The maximal delta of P1 and P2 all appear at similar to 800 nm and are 1010 GM and 940 GM per repeating unit respectively This suggests that no notable interactions among structure units that impair their fluorescence and TPA properties and the polymers with large delta can be obtained by using the high TPA active units as building blocks (c) 2010 Wiley Periodicals Inc J Polym Sci Part A Polym Chem 48 5704-5711 2010