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Attempts have been made to synthesize polyphosphazenes with pendent tertiary amino side units via macromolecular substitution. Incorporation of -OCH2CH2N(CH3)2, -OCH2CH2OCH2-CH2N(CH3)2, and -NHCH2CH2N(CH3)2 groups was studied. Polymers in which all the side groups consisted of one type of aliphatic tertiary amino-containing unit and species that also contained 2,2,2-trifluoroethoxy or phenoxy groups as cosubstituents were examined. Related phosphazene cyclic trimers were also prepared as small molecule model systems to examine synthetic variables, characterization techniques, and hydrolytic behavior. Those phosphazenes in which the tertiary amino-containing side groups are linked to the skeleton through an aliphatic oxygen-phosphorus bond are sensitive to hydrolysis induced by the basicity of the terminal amino group. However, species in which the tertiary aminocontaining units are linked to the backbone through an alkyl nitrogen-phosphorus bond are stable to water and are candidate materials for use in a range of membrane and surface applications. Small molecule model studies also identified reactions of P-Cl bonds in (NPCl2)3 with N,N-dimethylbutylamine to form dialkylamino-substituted phosphazenes and hydrolysis products.

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The synthesis and structure of a new class of poly(metallophosphazenes) is described. The polymers have the general formulas [NP(OR)j]b and [NP(OR)I(OCH2CF3)y]"> where the OR side group is (iie-2-phenoxyethoxy)chromium tricarbonyl and x + y = 2. The single-substituent polymer is the first example of a poly(metallophosphazene) that has one transition-metal unit on every side group. Nonmetallo polymers with the general structures [NP(OR')2]", [NP(OR')»(OCH2CF3)y]", and [NP(OCH2CF3)2]", where the OR' substituent is 2-phenoxyethoxy and x + y = 2, were prepared for comparison with the corresponding metallophosphazene polymers. Structural characterization for the high polymers was carried out by NMR spectroscopy, infrared spectroscopy, gel permeation chromatography, and elemental analysis. Thermal analysis of the polymers was investigated by differential scanning calorimetry and thermogravimetric analysis.

Poly(thieno [3,4-b]thiophene) (PTT) based transparent conductive polymers have been developed for hole injection layer (HIL) applications in polymer light-emitting devices. Using a second generation material that uses a poly(perfluoroethylene-perfluoroethersulfonic acid) as polymeric dispersant/counter-ion (PTT:PFFSA), significant improvement (up to 6 times with LUMATION Green 1304 as the light emitting layer) in PLED lifetime has been achieved compared to the lifetime of first generation PTT:PSSA (PTT:poly(styrene sulfonic acid)) based devices. Compared with the work function of 5.2 eV for PTT:PSSA film, PTT:PFFSA films have a higher work function of 5.5~5.7 eV. Interestingly, we found that the resistivity of PTT:PFFSA films is dependent on the film preparation conditions such as annealing temperature and time; while the work function of PTT:PFFSA films is independent on the film annealing conditions. We also studied the dependence of the device leakage current and lifetime on the preparation conditions of PTT:PFFSA based HIL films. Higher HIL annealing temperature results in higher device leakage current mainly due to the lower resistivity of the PTT:PFFSA HIL film prepared under such condition. However, the device lifetime is almost independent on the annealing temperature in the studied temperature range from 130 to 210 o C using dispersions with PFFSA-to-TT ratios of 12:1 and 18:1.