SU759544A1 - Method of preparing forpolymers - Google Patents

Description

The invention relates to the field of polymers, which can be used as compositions, varnishes and press compositions for electrical and electronic hrominnennosti, aircraft proklitsennosti, rocket production; automotive and possibly nuclear power. ten

'A known method of producing prepolymers willow based on N, Ν-bisimides of unsaturated dicharboxylic acids of the general formula

15

ω

20

where in is a bivalent radical containing a carbon-carbon double bond;

A - divalent radical soder- ^{/ e} zhaschy at least two carbon atoms [1].

For these compounds, radical or anionic homo- and copolymerization by double bonds is possible, B 30

in the latter case, the reaction is carried out in solution or molten state at elevated temperatures. However, the relatively short "lifetime" of the melt, the use of expensive high-boiling solvents, as well as the need to regenerate the solvent after the polymer is precipitated in water (when the reaction is carried out in solution), significantly limits the use of polybromine acids.

In order to reduce the temperature of the process and obtain solutions of prepolymers with an almost unlimited "lifetime", a method is proposed based on carrying out the reaction of nucleophilic addition of primary amines to Risimide Formula I in a solution of low-boiling solvents in the presence of soluble copper salts in the amount of 0.2-2 , 0 wt.%.

¹ The use of a catalyst (copper salt) and low-boiling solvents, such as dioxane, cyclohexanone, tetrahydrofuran, pyridine, reduces the synthesis temperature from 140–160 to 60–100 ° C, greatly facilitates the separation of the polymer from

759544

promotional solution, as well as solvent regeneration.

Polybysmaleimide formation can be represented by the following scheme:

ta; ; na and <>

+ ρΗ ^ -Β-ΗΗ ^ -

G ’

According to the proposed method, the reaction of attaching primary amines to unsaturated N,-bisimides is carried out in a solution of low-boiling solvents (dioxane, tetrahydrofuran, cyclohexanone, pyridine, etc.) at a temperature of 60-100 ° C for 0.51.5 hours, the ratio of the initial Ν, ίί-bisimide and diamine is from 1.5 to 5: 1, in the presence of copper salts (in an amount of 0.2-2.0 wt.%. The resulting polybismaleimide prepolymer drops out of the reaction solution when cooled to room temperature The prepolymer is separated by filtration, washed, dried. ·

The resulting prepolymer is soluble in the cold in acetone, chloroform, benzyl alcohol, dimethylformamide, dimethylacetamide, α-methylpyrrolidone, dimethyl sulfide, melts in the range of 70-150 ° C and can be used later both in solution and as a molding composition by heating the prepolymer in the temperature range 200300 ° C with the formation of a cross-linked, three-dimensional structure. Various fillers can also be added to the prepolymer.

According to the data of differential thermal and thermogravimetric analyzes, the prepolymers of polybysmaleimide do not emit volatile compounds until decomposition. The temperature of the beginning of decomposition of crosslinked polybysmaleimides exceeds 400 ° C (thermogravimetric analysis in air at a heating rate of 10 ° C / min).

Example 1. In a three-neck flask equipped with a stirrer, thermometer,

5 load 3.5835 g (1 mol) Ν, Ν ^Ζ (4,44-diphenylmethane) dimaleimide, 0.9908 g (0.5 mol) of 4,4-diaminodiphenylmethane, 16 ml of dioxane in the presence of 0.05 g of acetate copper used as a catalyst is stirred for 30 min at 65-66 ° C.

The reaction mixture is cooled to room temperature. The polymer falls out of the reaction mixture at the rooms. Noah temperature. The precipitated polymer <5 is filtered off and dried at 40 ° C in

'for 4 hours

Output 71.3% of theory.

Calculated,%: C 69.50; H 4.70;

N 12.00.

²⁰ ChdNavmd

Found,%: C 70.13; H 4.54,

N 11.40. ;

Example 2. In a three-neck flask equipped with a stirrer, a thermometer,

25 load 3.5835 g (1 mol) Ν, Ν ’(4,4'-diphenylmethane) dimaleimide, 0.9908 g (0.5 mol) 4,4'-diaminodiphenylmethane, 16 ml dioxane c. in the presence of 0.001 g of copper acetate, used as a catalyst, mix for 30 minutes at the boiling point of the solvent (101 ° C).

The reaction mixture is cooled to room temperature. After 3-5 hours, the polymer precipitates from the reaction CME B ^133. The precipitated polymer is filtered off and dried at 40 ° C for 4 hours.

Yield 60% off. theories.

Calculated,%: C 69.60; H 4.70 /

40 N 12.00.

^Χ 54 ^Η 20 ^Ν 4 ° 4

Found,%: C 71.00 ', H 4.56; N10.30.

Example 3. A three-necked col 45 bu, equipped with a stirrer and a thermometer, is charged with 3.5835 g (1 mol) M, 1G (4,4-diphenylmethane) dimaleimide, 0.9908 g (O, 5 mol) 4,4-diaminodiphenylmethane, 16 ml of tetrahydrofuran in the presence of

units 0.04 g of copper acetate used as a catalyst, stirred for 30 min at the boiling point of the solvent (b5-6 ^ *. C).

The reaction mixture is cooled to room temperature. The polymer falls out of the reaction mixture at this temperature.

The precipitated polymer was filtered and dried at 40 ^e C. • Techa of 4h.

60 Yield 70% of theory.

Calculated,%: C 69.50 H 4.70 ',

N 12.00. ,

Found,%: C 69.40; Η 4.80ί 65 N 10.30.

759544

Example 4. In a three-necked flask equipped with a stirrer, a thermometer, load 3.5835 g (1 mol) Ν, Ν '(4,4-diphenylmethane Dimalimide, 0.9908 g (0.5 mol) 4,4-diaminodiffeiylmethane,

16 ml of tetrahydrofuran in the presence of 5 Wii * 0.05 g of copper formic acid, used as a catalyst, is stirred for 30 minutes at the boiling point of the solvent (65-66 ° C). ten

The reaction mixture is cooled to room temperature. The polymer falls out of the reaction mixture at room temperature. The precipitated polymer is filtered off and dried at 40 ° C for 4 hours.

Output 60% of theory.

Example 5. In a three-neck flask equipped with a stirrer, a thermometer, load 1,7917 g (0.5 mol) _

Ν, Ν '(4,4-diphenylmethane) dimaleimide, * 0

1.9817 g (1 mol) of 4,4-diaminodiphenylmethane, 16 ml of dioxane in the presence of 0.05 g of formic copper, used as a catalyst, are stirred for 30 minutes at 65-66 ^o C.? 5

Cool the reaction mixture to room temperature. The polymer falls out of the reaction mixture at room temperature. The precipitated polymer is filtered off and dried at 30 ° C for 4 hours.

Yield 54% of theory.

Example 6. In a three-necked flask equipped with a stirrer, thermometer, Load 3,5835 g (1 mol) of N, N '(4,4-35-diphenylmethane) dimaleimide, 1,9817 g,

(1 mol) 4,4-diaminodiphenylmethane,

1.6 ml of dioxane in the presence of 0.05 g * of copper formic acid used as a catalyst is stirred for 30 minutes at the boiling point of the solvent (10 ° C)

The reaction mixture is cooled to room temperature. The polymer falls out of the reaction mixture at room temperature. The precipitated polymer is filtered and dried at 40 ° C for 4 hours.

Yield 50% of theory.

The method is characterized by ease of implementation, high yield of the target product, and the prepolymers obtained have good solubility, low melting point and can be used as impregnating compositions, varnishes and press materials in various fields of modern engineering and technology.

Claims (1)

Claim The method of producing prepolymers by reacting unsaturated dicarboxylic acids with N, бис-bisimides with primary diamines in an organic solvent medium when heated, is due to the fact that, in order to reduce the temperature of the process, the reaction is carried out in the presence of 0.2 to 2.0 wt.%.