Publication Type
Journal
Journal Name
Chemistry of Materials
Publication Date
Page Numbers
4367 to 4374
Volume
23
Issue
19
Abstract
The assembly and characterization of well-defined, end-tethered poly-
(p-phenylene) (PPP) brushes having high molecular weight, low polydispersity and high
1,4-stereoregularity are presented. The PPP brushes are formed using a precursor route that
relies on either self-assembly or spin coating of high molecular weight (degrees of poly-
merizations 54, 146, and 238) end-functionalized poly(1,3-cyclohexadiene) (PCHD)
chains from benzene solutions onto silicon or quartz substrates, followed by aromatization
of the end-attached PCHD chains on the surface. The approach allows the thickness
(grafting density) of the brushes to be easily varied. The dry brushes before and after
aromatization are characterized by ellipsometry, atomic force microscopy, grazing angle
attenuated total reflectance Fourier transform infrared spectroscopy, and UV-Vis spectros-
copy. The properties of the PPP brushes are compared with those of films made using oligo-
paraphenylenes and with ab initio density functional theory simulations of optical proper-
ties. Our results suggest conversion to fully aromatized, end-tetheredPPPpolymerbrusheshaving eective conjugation lengths of 5 phenyl units.