Aromatic Azopolymers Produced by Oxidative Coupling of Primary Aromatic Diamines

Abstract

SynopsisResults of the novel polymerization of primary aromatic diamines by oxidative coupling with oxygen as oxidant and the cupric-cuprous redox couple as catalyst are reported. The coupling reaction is generally applicable to aromatic diamines yielding a large variety of linear, high molecular weight polymers containing the oxidatively formed azo linkage as a part of the polymer chain. The oxidative coupling reaction, normally conducted a t room temperature and atmospheric pressure, is catalyzed by a cupric ion -nitrogen base complex. Tertiary amines such a s pyridine and disubstituted amides such a s dimethyl acetamide effectively serve as nitrogen bases in the complex and as solvents. No oxidative polymerization occurs in the absence of the catalyst. Catalyzed oxidation of primary aromatic diamines yields exclusively azo linkages, as is proved by independent synthesis of one of the polymers. Reactivity of primary aromatic diamines in oxidative coupling is positively related to their relative basicity. The azopolymers prepared are colored by the aromatic azo bond system incorporated; they are thermally stable and infusible. A number of compositions that made strong, flexible films were fabricated.

Azo Polymers

“…The catalyzed oxidative coupling of aromatic diamines has been intensively studied for the synthesis of polymers containing stable azo groups (69)(70)(71)(72)(73)(74)(75)(76)(77)(78)(79)(80)(81)(82)(83)(84)(85)(86). For example, aromatic amines have been studied with molecular oxygen in the presence of a Cu + /pyridine catalyst (87).…”

“…For example, aromatic amines have been studied with molecular oxygen in the presence of a Cu + /pyridine catalyst (87). This reaction has been used with a variety of primary aromatic diamines (69)(70)(71)(72)(73)(74)(75)(76)(77)(78)(79)(80)(81)(82)(83)(84)(85)(86).…”

“…Thermal stability is the most frequently studied property of azo polymers (69)(70)(71)(72)(73)(74)(75)(76)(77)(78)(79), and decomposition occurs above 350 • C. It has been suggested that a high degree of conjugation might lead to organic conductors or semiconductors. Electrical conductivity has been determined (53,54,73), and x-ray measurements made on cylindrical films (Debye-Scherrer measurements) of (49) and (47) have shown a high degree of crystallinity (77).…”

Bach-Type Polycondensation with the Aid of Hemoglobin as an Oxygen Supplier, and Synthetic/Bio-Composite

“…In 1966, Bach synthesized main chain-type polyazobenzene by Cu 2+ −catalyzed oxidative coupling (Scheme 1) [1]. This reaction requires oxygen for the polycondensation.…”

Aromatic Polyazines by a Copper‐Amine Catalyzed Oxidative Polymerization Reaction

“…[13 -15] Similar catalyst systems have also been used in the synthesis of polydisulfides [16 -18] poly(azo arylenes), [19,20] polyacetylenes, [21] and azoxyarylenes. [22] In this paper we report on the copper/amine catalyzed oxidative formation of azines from imines for the synthesis of polymeric azines.…”