Microphase separation-promoted crystallization in all-conjugated poly(3-alkylthiophene) diblock copolymers with high crystallinity and carrier mobility?

Journal of Materials Chemistry Pub Date: 2012-08-06 DOI: 10.1039/C2JM33204C

Abstract

The crystallinity of all-conjugated diblock copolymer, poly(3-butylthiophene)-b-poly(3-dodecylthiophene) (P3BDDT), with varied block ratios was significantly enhanced by a “two-step” thermal annealing treatment. The resulting P3BDDT exhibited an attractively high crystallinity of ～35%, which is a 3-fold enhancement over those of its homopolymer counterparts. The space-charge limited current (SCLC) mobility measurement revealed that the carrier mobility of the highly crystalline P3BDDT film was increased to as high as ～8.4 × 10?3 cm2 V?1 s?1, exceeding the highest SCLC mobility of poly(3-alkylthiophene) homopolymer films reported in previous work (i.e., ～1.6 × 10?3 cm2 V?1 s?1). DSC, XRD, AFM and SAXS characterizations demonstrated that the interplay of crystallization and microphase separation during the “two-step” thermal annealing treatment plays a key role in the improvement of P3BDDT crystallinity.

Graphical abstract: Microphase separation-promoted crystallization in all-conjugated poly(3-alkylthiophene) diblock copolymers with high crystallinity and carrier mobility
Recommended Literature