RU2022984C1 - Polymeric composition - Google Patents

Abstract

FIELD: chemistry and technology of high-molecular compounds. SUBSTANCE: polymeric composition has, wt.-%: polyamidobenzimidazole-4-phenyl- 2,2′, 5,5′ -tetramethyl-3-imidazoline-3-oxide-1-oxime 1.0-1.5, and carbon black 0.9-1.0. Composition shows resistance to the severe factors of cold climate and penetrating solar UV-radiation with minimal loss of physical-chemical indices. EFFECT: enhanced quality of composition. 1 tbl

Description

The invention relates to chemistry and technology of macromolecular compounds, in particular to composite polymer materials that can be used in various sectors of the national economy, where high demands are placed on these materials, in particular, to their properties that allow composite materials to withstand prolonged exposure to harsh factors of a cold climate and deep solar UV radiation with minimal loss of physico-chemical, mechanical indicators. The main requirement to composite polymeric materials, to provide a long operability products on their basis in extreme climatic conditions, when the Far North sharp seasonal temperature variations from -70 to 40 ° ^C.

 Polyamides are known obtained by solid-phase polycondensation in an inert gas stream based on diamines and dicarboxylic acids, in particular those obtained by polymerization of Σ-caprolactam, or based on hexamethylenediamine and sebacic acid. But all manufactured industrial polyamides are not stable against the effects of cold climate and deep UV radiation.

Also known are polyamidobenzimidazoles obtained by melt polycondensation based on bis-o-phenylenediamines, diphenyl ether of dicarboxylic acids and hexamethylenediamine based on these polymers having a high molecular weight (η _pr = 3.0-6.00 dl / g in HCOOH), are characterized high physical and mechanical strength properties, flexibility, elasticity. Compression materials based on them have σ _p = 30-55 MPa, E _p = 3-6%.

 The closest in technical essence to the achieved positive effect is a material comprising a heterocyclic polymer - polybenzimidazole and 4-phenyl-2,2 ', 5,5'-tetramethyl-3-imidazolin-3-oxide-1-oxime.

The disadvantages of the known synthetic polymer materials based on the above polyamides and polybenzimidazoles include the following:
after 4 months of exposure in a cold climate and deep UV radiation, samples are clarified on the surface of compression materials based on polyamides, cracks appear on the surface of the material after 9-12 months of exposure, which leads to destruction of the material;
in the case of polyamidobenzimidazole compression materials-analogues, during the year it decreases by 2 times, after 12-18 months. exposure to the surface of the samples scratches and cracks appear, which also leads to destruction of the material;
compression materials based on polybenzimidazoles containing 4-phenyl-2,2 ', 5,5'-tetramethyl-3-imidazolin-3-oxide-1-oxime under the same conditions practically retain their strength properties for 2 years, however, at further exposure, they become fragile.

 The aim of the invention is the stabilization of the physico-mechanical properties of polybenzimidazoles in cold climates and harsh UV radiation and expanding the range of composite materials.

 This goal is achieved in that polyamidobenzimidazoles (PABI), obtained by polycondensation of aromatic tetraamines, diphenyl ethers of dicarboxylic acids and diamines or Σ-caprolactam in a melt when heated in an inert gas stream, are dissolved in concentrated formic acid or dimethylformamide with stirring with stirring with stirring 4-phenyl-2,2 ', 5,5'-tetramethyl-3-imidazoline-3-oxide-1-oxime in an amount of 1.0-1.5 wt.% And soot in an amount of 0.9-1.0 wt.%.

Stirring was continued until a uniform suspension and subjected to heat treatment during 1.0-1.5 hours at a temperature of 20-50 ° ^C. Further, the suspension was added ammonia solution to precipitate fine powder poliamidobenzimidazola, stabilized powder separated on a filter, washed with water, dried .

Poliamidobenzimidazolnye molding powders are compressed by direct compression at temperatures of 180-260 ^{° C} and a specific pressure of 800-1,000 kgf / cm ² and compression produced materials having initial σ _p = 65-85 MPa, E _p = 3,5-4,5 % After exposure to cold climate and deep UV radiation during the exposure for 36 months in the conditions of Yakutsk, compression materials have high physical and mechanical strength indices: σ _p 49-63 MPa, E _p = 2.5-3.2% .

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Температура плавления 103-105^оС.For the synthesis of polyamidobenzimidazoles, bis-o-phenylenediamines of various structures can be used, preferably as 3,3'-diaminobenzidine, 3,3 ', 4,4'-tetraaminodiphenyl oxide, 3,3', 4,4'-tetraaminodiphenylmethane, 3, 3 ', 4,4'-tetraaminodiphenylsulfone, as well as adipic, sebacic acid diphenyl esters, various diamines, preferably hexamethylenediamine and Σ-caprolactam. The stabilizer used 4-phenyl-2,2 ', 5,5'-tetramethyl-3-oxide-1-oxime has the following structure
H

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Melting point 103-105 ^about C.

The decomposition temperature of 170-190 ^about C.

 The proposed method is confirmed by the following examples.

Example 1. A mixture of 34.545 g (0.15 mol) of 3,3 ', 4,4'-tetraaminodiphenyl oxide (TADPO), 44.73 g (0.15 mol) of diphenyl adipate (DFA) and 11, 31 g (0.10 mol) Σ-caprolactam (CL) is charged into the condensing tube, repeatedly blowing it with an inert gas: the tube was placed in a bath heated to ^about 200 C. The reaction mixture is melted, then the temperature within 1,0-1, 5 hours raise to 270 ^about C and maintain at this temperature for 4 hours, then create a vacuum of 1.0-2.0 mm Hg in the reaction system. and the reaction is continued for another 1.0 hour at the same temperature. The copolymer yield is almost quantitative. η _ol = 4.76 dl / g (in concentrated HCOOH, s = 0.5 g / dl, 20 ^° C). The copolymer is soluble in the cold in sulfuric and formic acids, amide solvents, tricresol.

The polymer is dissolved in condensed formic acid, adding with stirring a 1.0% stabilizer - 4-phenyl-2,2 ', 5,5'-tetramethyl-3-imidazoline-3-oxide-1-oxime and 1.0% carbon black from the polymer by subjecting to a heat treatment for 1.0 hours at a temperature of 20-50 ^{° C} to form a uniform suspension, then was added to a solution of ammonia-alcohol solution with stirring, separated fine powder is stabilized by a press filter, washed with water and alcohol and dried in cabinet at 100-120 ^o C.

The resulting powder was pressed in a mold by direct compression at 240-260 ^{° C} and a specific pressure of 800-1,000 kgf / cm ² and obtained compression material having an initial tensile breaking stress σ _p = 75-85 MPa and elongation at break E _p = 4.0%. After exposure to cold climate factors for 3 years, σ _p 60-63 MPa, E _p = 3.2%.

 The method of obtaining polyamidobenzimidazoles and the preparation of polymer compositions in examples 2-4 is similar to example 1.

PRI me R 2. Hinges are the same as in example 1, the stabilizer is 1.5 wt. % + carbon black 1.0 wt.%, σ _p and E _p in table 1.

PRI me R 3. Samples are the same as in example 1, the stabilizer is 1.0 wt.% + Carbon black 0.9 wt.%, Σ _p and E _p in table 1.

PRI me R 4. Samples are the same as in example 1, the stabilizer is 1.6 wt.% + Carbon black 1.0 wt.%, Σ _p and E _p in table 1.

PRI me R 5. A mixture of 23.03 g (0.10 mol) of TADFO, 11.62 g (0.10 mol) of hexamethylenediamine (HMD) and 70.88 (0.20 mol) of diphenylsebacinate (DPS) loaded into a condensation tube and then the process is carried out analogously to example 1. The reduced viscosity of a 0.5% polymer solution in HCOOH is η _ol = 2.53 dl / g. The polymer is soluble in the cold in sulfuric and formic acids, with slight heating in tricresol and dimethylformamide.

Press powder with the addition of 1.0 wt.% Stabilizer and 1.0 wt.% Carbon black is obtained analogously to example 1 and is pressed into the mold by direct compression at a temperature of 180 ^about and a specific pressure of 800 kgf / cm ² and get a compression material, having σ _p = 67-70 MPa, E _p = = 4.0%. After exposure to cold climate factors for 3 years, σ _p = 69-70 MPa, E _p = 3.6%.

PRI me R 6. The hinges are the same as in example 5, + stabilizer 1.5 wt.% + Carbon black 1.0 wt.%, Σ _p and E _p in the table.

 The proposed polymer compositions are resistant to the effects of cold climate. During the exposure in cold climates and harsh UV radiation for 36 months, they practically retain their initial physical, mechanical and physico-chemical characteristics (see Table 1).

 It should be noted that it is enough to introduce 1.0-1.5 wt.% 4-phenyl-2,2 ', 5,5'-tetramethyl-3-imidazoline-3-oxide-1-oxime and 1.0 wt.% soot in PABI, so that the copolymers become resistant to the effects of cold climate and deep solar UV radiation. Such polymer compositions can be used as compression and composite polymer materials capable of withstanding the effects of cold climate factors.

Claims (1)

POLYMERIC COMPOSITION containing a heterocyclic polymer, 4-phenyl-2,2 ¹ , 5,5 ^1- tetramethyl-3-imidazolin-3-oxide-1-oxime, characterized in that, in order to stabilize the physicochemical, physicomechanical the properties of the composition when exposed to factors of a cold climate and deep solar UV radiation, it contains polyamidobenzimidazole as a heterocyclic polymer and additionally contains soot in the following ratio of components, wt.%:
4-Phenyl-2.2 ¹ , 5.5 ^1- tetramethyl-3-imidazolin-3-oxide-1-oxime 1.0 - 1.5
Soot 0.9 - 1.0
Polyamidobenzimidazole Else

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