SU418064A1 - Method of producing polyamides with free amino group - Google Patents

Description

one

The invention relates to the preparation of polymers.

A known method for producing polyamides with free amino groups is by polycondensation of tetraamines and dicarboxylic acid dichlorides.

However, the polymers obtained have a low molecular weight (the reduced viscosity in concentrated sulfuric acid is 0.08-0.22), which makes it difficult to use them practically. ,

In order to obtain high molecular weight polymers, a method for the production of polyamides by polycondensation of difluoroanhydrides of aromatic dicarboxylic acids and tri- or tetraamines is proposed.

The reaction is carried out in a solvent, for example dimethylacetamide, dimethylformamide, dimethyl sulfoxide, N-methyl-L-pyrrolidone and other similar solvents at -30-0 ° C using a catalyst, for example carboxylic acids. The catalyst is injected into a solution of tetraamine or difluoroanhydride. Best results are obtained when introducing it into the diftoran hydride solution.

The proposed method involves the gradual introduction into the solution

etraamine difluoroanhydride in solid, in the form or in the form of a solution with a certain speed in an equimolar ratio or in an amount that provides a 0.1-1% excess.

The polymers obtained by the proposed method have a high molecular weight (reduced viscosity f)

 Example 1. To a solution of 2.3028 g of tetraaminodiphenyl ether (TADPE) in 34 ml of dimethylacetamide (DMAA) at -20 ° C is added a solution of 1.7012 g of difluoroanhydride of isophthalic acid (FAIC) and 0.915 g of benzoic acid over 1 hour (BK) in 17 ml of DMAA. The solution is stirred for 5 hours at -20 ° C and left for 16 hours at room temperature. The resulting polymer is then separated by precipitation into water, washed from HF and dried. The reduced polymer viscosity in sulfuric acid is given in HjSC. 1.2.

Note 2. To a solution of 2.3028 g

TADA in 34 ml of DMAA with a solution of 1.7012 g of FAIK and 0.6 g of acetic acid in 17 ml of DMAA is added over 1 hour. The solution is stirred for 5 hours at -20 ° C and left for 16 hours.

Claims (1)

at room temperature. The formed polymer is precipitated into water / washed from HF, dried, InpHB 2 0, -P-Mp and measure 3. To a solution of 23028 g of TADPHE; in 17 ml of DMAA at -20C a solution of 1.7012 g FAIK and 0.915 g of BQ in 17 ml of DMAA is added over 1 hour. The solution is stirred for 5 hours at and left for 16 hours at room temperature. The polymer formed is precipitated into water, washed from HF and washed 11 "in H 5O, -I curve J Example 4, To a solution of 2.3028 g TADPE ml DMAA, FAIC solution 1.7012 is added over 1 hour. and 2.11) 43 g of tert-amyltoluic acid in 17 ml of DMAA. The solution is stirred for 5 hours at -20 ° C and left for 16 hours at room temperature. The polymer formed is isolated by sedimentation in WATER, washed from HF, dried in I, SO, o Cr; - Precipitation of polymers into water immediately after 5 hours of stirring at -20 ° C leads to the formation of a gel due to the fact that during the precipitation process the interaction of the remaining fluoride hydride groups with amines, begins to be determined not by energy, but by steric factors. If the synthesis is carried out under optimal conditions that ensure the most complete consumption of the fluoride hydride groups during the reaction, the polymer can be isolated by precipitating the RAM into the water after 5 hours of stirring at -20 ° C. However, there is still some possibility of formation of branched structures, however, the polymer remains completely soluble, although more twist is commolecular. So, the polymer obtained according to / example 3 and planted in water immediately after 5 hours of mixing, is completely soluble in DMAA, sulfuric acid and has IrridB, 8. Separation of the polymer is possible in other ways, for example, by hydrolyzing or blocking the hydrofluoric acid groups during the precipitation process. Thus, precipitation of the polymer into an ammonia solution allows the preparation of soluble polymers. Obtaining polymers by the proposed method can be carried out in a solution of technical dimethylacetamide with high humidity. All the polymers obtained are soluble in concentrated sulfuric acid, dimethyl acetamide and other amide-type solvents. Polymer solutions can be stored for a long time (the specific viscosity in concentrated sulfuric acid for 300 hours varies from 1.1 to 1.04). The resulting polymers can be used directly or to make other polymers, for example polybenzimidazoles. Heating the polyaminoamide, g B, for 4.5 hours at 300–360 ° C in vacuum leads to its conversion to polybenzimidazole with 14% I, 14. The invention The method of obtaining polyamides with. free amino groups by polycondensation of tri- or tetraamines and aromatic dicarboxylic acid halides, 1 characterized by chuo, for the preparation of high molecular weight polymers, aromatic dicarboxylic acid difluorohydrides are used as halides of hydride.