Investigation of poly(arylenevinylene)s, 42. Synthesis of PPV-based copolymers containing alkyldiphenylamine and triphenylamine in the main chain

Abstract

SUMMARY: PPV-based copolymers carrying in-chain tertiary amino groups have been synthesized by Horner-type polycondensation of arylamine dialdehydes and alkoxy-substituted xylylene bis(phosphonate)s: [1NR1C 6 H 4 1CH2CH1C 6 H 2 (OAlkyl) 2 1CH2CH1C 6 H 4 1] n 6. Several compounds with the general structure 6 and containing methylamino, cyclohexylamino, and phenylamino groups have been prepared and analyzed. Incorporation of electron-rich amino groups into the PPV backbone does not interrupt the main-chain conjugation but has the effect of reducing the oxidation potential, thus transforming these polymers into highly photoconducting and hole injecting/hole transporting materials. These new polymers were evaluated using photoluminescence and cyclic voltammetry methods and characterized by gel-permeation chromatography (GPC) and DSC. The chemical structure was confirmed by NMR-and UV/VIS absorption spectroscopy. The polymers 6 are well-defined, completely soluble materials of high molecular weight (M -w A 20 000). They possess all-trans vinylene units and exhibit a strong green photoluminescence (U PL L 70%). Solutioncast solid films show an outstanding photoconductivity in the UV/VIS range.

Pentadecamer 2,5-Dipropoxy-1,4-phenylenevinylene

“…[19] The 5-(2-ethylhexyloxy)-2-methoxy system, which is related to 1p, exhibits in dioxane a λ max value of 498 nm. [19] The exact endgroups are not known, but again one has to assume terminal electronwithdrawing substituents, namely phosphonate and/or formyl groups, which induce a charge transfer effect.…”

Effect of Varying Thiophene Units on Charge‐Transport and Photovoltaic Properties of Poly(phenylene ethynylene)‐alt‐poly(phenylene vinylene) Polymers

“…[10][11][12][13][14] PPV derivatives exhibit rather low oxidation potential (low-lying highest occupied molecular orbital (HOMO)) and low reduction potentials (high-lying lowest unoccupied molecular orbital (LUMO)). [ 15 ] In contrast poly(phenylene ethynylene) (PPE) derivatives in which the vinyl double bonds of PPV backbone has been replaced by ethynyl triple bonds, possess relatively high reduction potentials (low-lying LUMO), [ 16 ] due to an enhanced electron affi nity induced by the electron-withdrawing character of the C C units. [ 17,18 ] Moreover PPEs possess a highly rigid conjugated structure leading to characteristics, which differ from the ones of PPV, e.g., polarization and molar extinction coeffi cients.…”

Synthesis and Characterization of a Novel Class of PPV Derivatives Covalently Linked to C60

“…Carbazole and triphenylamine moieties are also introduced into the copolymer main chains taking into account that copolymers containing the carbazole or triphenylamine moiety usually exhibit good electro-/photoactive properties, which make them suitable materials for application in light-emitting diodes and other optoelectronic devices. [11][12][13] Experimental Part Materials and Measurements 1,4-Dipentoxybenzene (1), [14] N-(3-bromopropyl)carbazole (4) [15] and 4,49-diformyltriphenylamine (7) [13] were prepared according to procedures reported in the literature. All solvents were distilled prior to use.…”