Functional Disubstituted Polyacetylenes and Soluble Cross-linked Polyenes: Effects of Pendant Groups or Side Chains on Liquid Crystallinity and Light Emission of Poly(1-phenyl-1-undecyne)s

A group of new poly(1-phenyl-1-undecyne)s with different mesogenic and chromophoric pendant groups or side chains were successfully synthesized and the structural variations were found to greatly affect the mesomorphic and luminescent properties of the polymers. The 1-phenyl-1-undecyne monomers (C6H5)C⋮C(CH2)9OCOR with R = C6H4−C6H10−C5H11 (1), C6H4−OCO−C6H4−OC6H13 (2), and C6H4−C⋮C−C6H4−OC7H15 (3) were prepared by simple esterification and/or coupling reactions. The polymerizations of 1−3 were effected by WCl6−Ph4Sn in toluene at 60−80 °C, giving polymers with high molecular weights in good isolation yields. The structures and properties of the polymers were characterized and evaluated by GPC, IR, NMR, TGA, DSC, POM, XRD, UV, and PL analyses. The polymerizations of 1 and 2 yield linear poly(1-phenyl-1-alkyne)s P1 and P2, respectively, while that of 3 gives a nonlinear macromolecule with its poly(1-phenyl-1-alkyne) main chain cross-linked by the oligo(diphenylacetylene) side chains resulted from the parti...