N.A. Churochkina

The structure of fatty aromatic polyimides

Abstract It is shown that orientated, crystalline films can be obtained from polyalkylene-imides derived from 3,4,3′,4′-tetracarboxydiphenyl oxide and 1,6-hexamethylene-1,8-octamethylene and 1,10-decamethylenediamine. The structure of the films was studied by the X-ray diffraction method and electron microscopy. It was found that the polymer from 1,8-octamethylenediamine shows the greatest tendency to crystalline. The unit cell of the crystal and the density of the crystallites have been determined for this polymer, and a model of the macromolecule has been constructed. The conditions for crystallization and conversion to the amorphous state have been found, and the degree of crystallinity of some smaples has been determined. Electron photomicrographs and electron diffraction patterns of fibrillar and lamellar structures in orientated, crystalline films, have been obtained.

The hydrodynamic properties of the polyimide from the dianhydride of 3,4,3′,4′-tetracarboxydiphenyl oxide and 9,9-bis-(4-aminophenyl) fluorene☆

The hydrodynamic properties of solutions of a polyimide from the dianhydride of 3,4,3′,4′-tetracarboxydiphenyl oxide and 9,9-bis-(4-aminophenyl)fluorene have been investigated and the parameters of the equations relating [ν] to S0andMw have been determined. It was found that beginning at Mw=400 × 103 the behaviour of the polymer molecules in solution is in accord with the theories of non-free-draining Gaussian coils. The length of the Kuhn segment characterizing the chain rigidity is A = 20–21 A.

Synthesis and properties of mixed cardic polyimides

Mixed polyimides from the dianhydrides of pyromellitic acid, 3,3′,4,4′-diphenyltetracarboxylic acid, 3,3′,4,4′-tetracarboxydiphenyl oxide and 3,3′,4,4′-benzophenonetetracarboxylic acid, reacted with the following diamines: 9,9-bis(4-aminophenyl)fluorene, 9,9-bis(4-aminophenyl)anthrone, 3,3-bis(4-aminophenyl)phthalide and 4,4′-diaminodiphenyl oxide, have been synthesized and studied. It is shown that in this series of capolyimides their properties (solubility in organic solvents and softening point) are dependent mainly on the chemical structure of the acidic component. It was found that heat treatment of films of mixed polyimides containing 3,3′,4,4′-benzophenonetetracarboxylic acid radicals increases their strength characteristics considerably.

The synthesis of polyaspartimides in solution

The mechanisms of the migrational copolymerization of cardio bis-maleimides with cardo diamines, yielding a water-soluble polyaspartimide, have been investigated. The process has been carried out in m-cresol at 150°C over benzoic acid as catalyst. The aspartimide and maleimide fragments have been found to resist a transamidation under selected synthesis conditions.

Synthesis and properties of siloxane-containing card-like copolymers☆

High-molecular (Mw = 87000–137000), film-forming card-like copolyimides, siloxane-containing and soluble in organic solvents, have been obtained from siloxane-containing diamines, namely, 1,3-bis-(3-aminopropyl)tetramethylsiloxane or α,ω-bis-(3-aminopropyl)oligodimethylsiloxanes having n dimethylsiloxane fragments where n = 29, 39 or 99, with the card diamines, namely, 9,9-bis-(4′-aminophenyl)fluorene, 3,3′-bis-(4′-aminophenyl)phthalide and the dianhydrides of 3,3′,4,4′-tetracarboxydiphenyl, 3,3′,4,4′-tetrabenzophenone, and 3,3′,4,4′-tetradiphenyl oxide. The dependence of the properties of the copolyimides on the following has been established: the chemical structure of the card group, the presence and form of the bridge group in the arylenimide fragment and the amount and length of the oligodimethylsiloxane fragment.

Synthesis and properties of polyamides with diphenylene anthracene fragments in the macromolecules

Abstract The patterns of low temperature polycondensation of 9,10-bis-(4′-aminophenyl)anthracene and terephthaloyl chloride in amide solvents have been studied. High molecular weight homo-and co-polyamides have been obtained based on 9,10-bis-(4′-aminophenyl)antracene, p -phenylene diamine, 9,9-bis-(4′-aminophenyl)fluorine, 5(6)-amino-2(4′-aminophenyl)benzimidazole and the chloranhydrides of adipic, sebacic, tere- and iso-phthalic acids, 2,2-bis-(4-carboxyphenyl)hexafluoropropane and 3,3-bis-(4′-carboxyphenyl)phthalide. Strong films have been obtained from homo- and co-polyamides soluble in amide solvents.

Synthesis of polyketones from chlorides of aromatic dicarbocylic acids and samarium(II) iodide

Abstract Homo- and copolymeric α-diketones were prepared by reacting chlorides of dicarboxylic acids (terephthalic, isophthalic, 2,2-bis(4-carboxyphenyl)hexafluoropropane) with samarium diiodide in tetrahydrofurane. Some of the products are soluble in N-methyl-2-pyrrolidone, dimethylformamide or dimethylacetamide. A study of the synthesis of polyketones and also of a model compound - benzil - led to the conclusion that the resulting polymeric α-diketones are chemically heterogenous and contain vicinal diketogroups along with hydroxymethylene groups.