cancellation in alignment between the two mesogenic cores of the rigid polyene
main chain and the LC side chain that are almost orthogonal to each other. Among
Group 1 and Group 2 di-LCPAs, the polymers bearing the double mesogenic core in
side chains (PA12, having the stilbene and terphenyl mesogens; and PA14, having
stilbene and PCH mesogens) are the most promising for the dichroic emissive PAs,
Fig. 6 (a) Linearly dichroic PL of aligned PA11, (b) XRD pattern of aligned PA11 shows a broad
peak at 4.5 Å (19.6
in 2θ) corresponding to the distance between the terphenyl LC moieties in the
side chains, inset: XRD Laue pattern of aligned PA11 film, and (c) orientation diagram of aligned
PA11. (d) Linearly dichroic PL of aligned PA13, (e) XRD pattern of aligned PA13 shows peaks at
31 Å (n = 2, 5.7
in 2θ) and 4.9 Å (18
in 2θ) corresponding to the interlayer distance of the main
chains and the distance between the PCH LC moieties in the side chains, respectively, and (f)
orientation diagram of aligned PA13. (g) Linearly dichroic PL of aligned PA14, (h) XRD pattern of
aligned PA14 shows a peak at 5.0 Å (17.8
in 2θ) related to the distance between the PCH LC
moieties in the side chains, and (i) orientation diagram of aligned PA14. Rectangles with orange
broken lines in (c, f, and i) indicate dominant emission moieties in the polymers (San Jose 2011)
12 Liquid Crystalline Conjugated Polymers with Optoelectronic Functions
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