SU739078A1 - Method of preparing polyamidophenylquinoxalines - Google Patents

Description

(540 METHOD OF OBTAINING POLYAMIDOPHENYL-KHINOXALINES

The invention relates to the preparation of nitrogen-containing polyheteroarylenes, in the structure of which phenylquinoxaline and carborane fragments are present, linked by amide groups. The presence of phenyl quinoxaline and carborane cycles in polymer chains causes a combination of high heat resistance of polymers and solubility in organic solvents with increased resistance to thermal destruction. Carborane-containing polyamides of amidophenylquinoxalines will find use as heat and heat resistant structural materials, glue Eve compositions, film materials, coatings and fibers. A known method of obtaining polym dophenylquinoxalines by reacting in m-cresol at 200 ° C aromatic tetramines with bis (oL-diketones) of the following structure: oVcO-CO-X-NHCQ-A -CONH-Y-CO-CO- - or p-fenylene; AG 0-p, m- or p-phenylene or., (, O, S, SO, SO) 11. The disadvantage of this method is the use of toxic m-cresol as a solvent and carrying out the reaction at high temperatures (00 °) in for 2-4 hours. The polyamidophenylquinoxalines obtained by this method have relatively low TC (below 300 °), which prevents their use at higher temperatures. According to TGA (L, T 4.5 K / min), they completely decompose when heated in air to. The aim of the invention is to synthesize polyamidophenylquinoxalines, having a high thermal characteristics. This goal is achieved by using a compound of formula 2-mmssac (H ° or its mixture with other (and known) dried tetraketones) as bis (e, -diketone), and chlorinated hydrocarbons in the presence of a catalyst — a proton donor — are used as solvents. 20-25 ° C,

The interaction of bis- (cC-diketone)

The introduction of carborane cycles into the structure of polyphenylquinoxalines alters their thermal characteristics, especially noticeably increasing resistance to thermal-oxidative degradation. Thus, the softening temperatures of all carborane-containing polyamidophenylquinoxalines lie above 300 ° C when heated in air to 600 ° C. These polymers retain 70–90% of their initial weight (high coke residues).

The introduction of carborane fragments into polyphenylquinoxalines leads to an improvement in the physicomechanical properties of the films, in particular, the elongation at break increases by an order of magnitude, reaching f 300%, unlike all

(or its mixtures with other tetraketo-, us) with aromatic tetramines obtained carborane-containing polyamidophenylquinoxalines of different composition, in which the number of carborane fragments varies, with the general formula;

MYAtyNY.

R

Well

otsshshnyh polyheteroarylenes with very low deformation ((5 °; 10%).

The polymers obtained by the process have good solubility and

can easily be recycled into products already in cyclized form. Products from them are distinguished by high deformation-strength properties, which are preserved at high temperatures.

The structure of the synthesized carborane-containing polyamidophenylquinoxalines is confirmed by the identity of the IR spectra of polymers and model

compounds obtained by treating 4, 4-bis- (phenylglyoxalyl) -m-carboranylenedianilide-o-phenylenediamine.

NHCOCB gH gCCONH

. In the IR spectra of polymers and model compounds, the absorption at 2600 and 1700 cm is characteristic of the stretching vibrations of B – H and amide bonds, respectively.

The advantage of the proposed method in comparison with the known method is the elimination from the synthesis of toxic. Characteristics of polyamidophenylquinoxalines of the general formula:

go m-cresol and holding it at room temperature. Received

however, the polymers have high viscosity characteristics and, consequently, high molecular weight. The characteristics of the homo1 {copolymers obtained are given in the table,

in which conventional polyphenylquinoxaline is presented for comparison.

S (SY

N,

five

Tw

1.2 Not once- 570 1.8 - -530

100 25

75 2.75 --520

90

m is getting hot

90

75

Note,

The method of obtaining a new bis-fct, -cyketone) -4,4 -bis- (phenylglyoxalyl) -m-carboranylene dianilide and the synthesis of carborane-containing polymers

2 (ОУсо-со-{-ын2 се, sosOs osess

ousO-soo) -diss dN somn-uso-co @

in a three-necked flask equipped with a stirrer, an injection for argon and an addition funnel, a solution of 2.25 g is prepared

(0.01 mol) 4-aminobenzyl in 10 ml of tetrahydrofuran and 1.01 g added

(0.01 mol) of triethylamine. 1.35 ml is added dropwise to the solution.

(0.004 mol) of m-carborane dicarboxylic acid dichlorohydride, and a precipitate of hydrochloric triethylamine is observed. The reaction mixture is stirred at room temperature for 2 hours, then the precipitate is from

Table continuation

) Measured for 0.5% solution in

m-cresole at 25c. ) From thermochemical curves) According to the data of dynamic thermogravimetric analysis, AT 6 deg / min in air.

dophenylquinoxalines consists in

next.

Synthesis of 4,4-bis- (phenylglyoxide} -m-carboranylene dianilide

filter from solution, solution

5 is evaporated on a rotary evaporator and the precipitate formed is crystallized from a mixture of benzene: heptane. Output 90% of theory. Tp 201-203C.

Found,%: C H 4.98; and 4.60; At 16.25.

Calculated dl, В „, О,%:

1I SzaNeo;

At 16.73. ; N 4.33, Example 1. Synthesis of Carborai45 containing polyamidophenylquinoxaline of the new General Formula:

To a suspension of 0.4605 g (0.002 mol) of 3.3, 4.4-tetra-aminodiphenyloxide () in 5 MP of chloroform: methanol in a ratio of 10: 1 at room temperature and stirring, 1.2936 g (0.002 mol) 4 are gradually added. , 4-bis- (phenylglyoxalyl) -m-carboranylene dianilide. The reaction mixture is stirred at room temperature in a stream of argon for 3 hours, after which the polymer solution is diluted with 10 ml of chloroform

and poured into methanol. The polymer is filtered off, washed with methanol and dried.

Polymer yield quantitative, fp 1.8 dl / g (0.5% solution in m-cresol at. The value of the coke residue at 90%. According to the thermomechanical curves, the polymer does not soften c.

Example 2.- Preparation and isolation of the polymer as in Example 1, but using as tetramine

0.4284 g (0.002 mol) of 3, 3-diaminobenzidine (R -) PPr DL / g (0.5% solution of m-cresol at 25 ° C).

PRI me R 3-5. Copolymers containing carboranic and phenylquinoxaline cycles in the structure are prepared and isolated as in Example 1, using the bis - ("{gdiketones): 4,4-e) Is- (phenylglyoxalyl) -m-carboranylenedylenilide in the reaction in different ratios. and 1,4-bis- (phenylglyoxalyl) benzene.

Films obtained by pouring from 10% solutions of polymers and copolymers in chloroform on a cellophane g substrate have G 900–1,200 kg / cm € - 180–280%.

Thus, the introduction of carboranic cycles in the polyphyl l. Quinoxalines has a stabilizing effect.

(o) -CO-CO-O NHCOCB, jjH QCCOHN-CO-CO or its mixture with other tetraketones, and-chlorinated hydrocarbons are used as solvents in the presence of a proton donor catalyst at 2 0-25 C.

on polymers, which can be explained by the formation of more heat-resistant partially cross-linked structures in the process of destruction, apparently due to various transformations of the m-carborane group, under the action of amide and reactive terminal amino groups.

Claims (1)

Invention Formula The method of obtaining polyamide-phenylquinoxalines by reacting bis (cC-diketones) with aromatic tetraamines in an organic solvent, characterized in that in order to show thermal characteristics of the product, a compound of the general formula b- (ot-diketone) is used Sources of information taken into account in the examination 1, US Patent 3,746,687, Cl. 260.2, published. 1973 (prototype).