composed of a mixture of ordered and amorphous regions. Crystalline lamellae
formed of planar, stacked chain segments are separated by interlamellar amorphous
domains comprising chain ends, chain folds, and long tie-chains, the latter
interconnecting neighboring crystallites. Although little is known about the precise
nature of these interconnections, qualitative considerations were proposed by
0
0
30
20
10
width
mobility
W AFM = 1.0 X L W + 6.0
0
5
1 0
10
15
20
20
30
40
10 –2
10 –3
10 –4
10 –5
10 –6
L W – Weight Average Contour Length (nm)
M W – Weight Average Molecular Weight (kDa)
Mobility (cm
2
/Vs)
W
AFM – Nanofibril Width (nm)
Fig. 12 Evolution of P3HT nanofibril width W AFM and hole mobility μ as function of weightaverage molecular weight M w and weight-average contour length L w [79]. Thin films were
prepared by drop-casting from toluene (1 mg/mL). (Reprinted with permission from Zhang
et al. [79]. Copyright (2006) American Chemical Society)
Fig. 13 Microstructure in P3HT thin films: (a) molecular arrangements of the polymer chains
within the nanocrystalline lamellae, which are separated by amorphous domains; and (b) mesoscale morphology of P3HT consisting of crystalline lamellae (dark grey) separated by amorphous
domains (light grey). Tie-chains connecting adjacent lamellae are shown in red. Image courtesy of
Florian Fischer
Morphology of P3HT in Thin Films
59