SU1126570A1 - Process for preparing imidazoline curing agents for epoxy resins - Google Patents

Abstract

METHOD OF OBTAINING IMIDAZOLINE CALENDARS OF EPOXY RESINS by condensation of mono-, di- and / or polycarbric acids with ethylene-polyamines of the formula (-CH2CH2NH) -Hj where n 1-10, with the addition of equivalent quantities of C | C., p-unsaturated acid and polyamine of the specified formula with the ratio of scientific research institute carboxylic and d, / z-nenasy. from 10: 1 to 10:13 at 120-280 ° C, characterized in that, in order to increase the reactivity of hardeners at room temperature, the resulting imidazoline hardener is further condensed with a mono- or poly-acid Mannich base at 100-150 &; ° C at a molar ratio of imidazoline hardener and Mannich base from 2: 1 to 10: 1.

Description

This invention relates to a process of obtaining and imidaeolin hardeners for epoxy resins. A known method for the preparation of imidazoline hardeners, which consists in the condensation of mono-, days (or polycarboxylic acids with polyamines of the ethylene series Cl). By a known method, compounds of the formula - / g: K-CH2-CHj-NH-R O where R is MONO-, di- or polyvalent organic radical — carboxylic acid residue; p 1-10; RH, -CH2CH2NH2, CH., CH2NHCH2CH2NH, and the like. The lack of imidazole NOVA hardeners of the general formula (I) is EYALABST with their low reactivity at room temperature, which is related to the structural features of imidazoline hardeners, because to obtain a complex of indicators during curing of epoxy / g-C-CHj-CHgNH-CH s /

where r

CHgCH -, CH jjCH NH-CH, jCHj, etc.

R, R, n - is higher than the value.

A disadvantage of the obtained hardeners is their relatively low reactivity at room and low temperatures. Thus, to obtain epoxy polymers with sufficiently high strength and thermophysical parameters, the epoxy imidazoline compositions during the curing process must be treated at 80-120 ° C. Without heat treatment, the properties of epoxy polymers remain 40-100% lower even after exposure to cold for 4 months. It can also be noted that even for the most active hardeners such as adipic, azelaic and sebacic acid bimimidazolines, for which the gelatinization time with ED-20 epoxy resin varies from 2 to 5 hours, the time required for a set of minimally acceptable

 strength from: Verification in cold weather is 7-15 days. For this reason, imidazoline hardeners obtained in a known manner are practically unsuitable for curing epoxy resins at and below. These disadvantages substantially limit the scope of application of the known imidazoline hardeners and, of course, narrow the scope of application of the known methods for producing such compounds.

The purpose of the invention is to increase the reactivity at room temperature.

This goal is achieved by the fact that according to the method of obtaining imidazoline hardeners of epoxy resins by condensation of mono-, di- and / or polycarboxylic acids with polyamines of ethylene series

(,

where n 1-10,

with the addition of equimolar amounts

o (, - unsaturated acid and polyamine resins require heat treatment of the polymer material at a temperature not lower. Without such heat treatment, i.e., with pure cold curing, as well as during curing of epoxy resins with imidazoline strippers at 10-15 0, high level properties are not achieved even after 3-4 months of delivery.The closest to the proposed technical essence is the method of obtaining imidazoline hardeners, which consists in the condensation of MONO-, di and / or polycarboxylic acids with polyamides of ethylene Formula H2N (-CH2-CH2-NH) 2-H, where n 1-10, at 120-280C with the addition of an equivalent amount of t / L, -unsaturated acid and ethylene polyamine of the specified formula with a ratio of carboxylic acid aei, p- unsaturated acid from 10: 1 to 10:13 C23. The resulting hardener contains imidazoline compounds of the formula (I) and compounds of the new structure of the general formula "1, (П) КНj -Jn 3.. 1 of the specified formula with the ratio / carboxylic acid and o (-, - non-nascent acid from 10: 1 to 10:13 at 120-280 C; the adazoline hardener obtained by it is further condensed with Mannich mono-or poly-acid base with lOO-ISO C at a molar ratio of imidazoline hardener and Mannich base from 2: 1 to 10: 1. The obtained hardeners have reactivity close to imidazolines in the initial stages and at the same time provide the production of polymeric materials with a complex of valuable properties after 15–20 days of exposure to cold without special heat treatment. At the same time, epoxy compositions gain a minimum acceptable strength after 1–3 days of exposure, similar to the same eksperi ny compositions with polyethylenepoly us. The proposed method is characterized by simplicity and does not require the use of special equipment, the reactions proceed fairly quickly at very high temperatures (100-150 ° C). All necessary for

HjKCHjCHzN-CCHzle; -N-CHjCHzNHj,

4.N (W)

HiUCHjCHjN- (CH CH CHjNHCH CHj CH, NH, / NsyNxy

By calculation, the molar ratio of compounds (III): (IV) 7: 3. The resulting product is a viscous, non-crystallizing liquid with the following physicochemical indicators:

Found

Calculated 397

381.9

(Iv)

Density at 25 ° С, g / cm3

1.08 The refractive index 1

1.5237 nor

B. Synthesis of target imidazoline hardener.

376.9 g of the imidazoline hardener obtained in A are placed in a four-necked flask equipped with a mechanical stirrer, a thermometer, a dropping funnel and a reflux condenser connected to an absorption column which is filled with 10% gray acid (an indicator is installed between the absorption column and the reflux condenser) 04 implementations of the proposed method, the initial products are available. EXAMPLE 1. A. Synthesis of the initial imidazoline hardener, To a round bottom chetyrehgor 1st flask equipped with a thermometer, mechanical mesh 206 g (2 mol) of diztilentiriamine and 202 g (1 mol) of sebacic acid are simultaneously charged at the same time as a bubbler for supplying nitrogen under a layer of liquid and a packed column connected to a direct cooler and distillate collector. The mixture is heated to 60 ° C and stirred to 30 g (0.3 mol) - methyl methacrylate and 31 g (0.3 mol) diethylenetriamine are additionally introduced; the mixture is heated to 80 ° C with continuous stirring and supply of nitrogen for 3 hours. Next, the temperature of the reaction mass is gradually increased to 200 ° C, while methanol is distilled off simultaneously. Next, the temperature is raised to 250 ° C. The reaction water is distilled off. After separation of the total amount of water, the reaction mass is cooled to 60 ° C and drained. Obtain 376.9 g (98.7% of theoretical) mixture of compounds of the formulas of the gas stream). The contents of the flask are heated to 130-140 ° C and 44 g (0.166 mol) of 2,4,6-tris (dimethylaminomethyl) phenol, UP-606/2, is added dropwise slowly, simultaneously the distillation of dimethylamine is formed. Pegemixing of the reaction mixture with PO-COC is continued until complete separation of dimethylakin.

R - l HCH-t CHzKH-Bi,

I41 11 / -CH2CH2N- (CH2) j-N-CH2CH2NH2; -Sch (v)

CH2 "H-H1 CH2N- (CH2) 8 -NCH2CH2NHCH2GH-N-CH2CH2NHj Synthesis of the starting and further target imidazoline hardener can be carried out continuously in one {. reception 402.8 g (99.8% of theory) of a dark colored viscous product are obtained containing compounds of the general formula

CH2-CHjN-CH-CH2NHCH2CH2W This is a compound obtained in a mixture. e the initial imidazoline, and the molar ratio of the compounds (III): (IV) :( V) 10: 7: 3 is calculated from the ratio of the starting components). The resulting hardener has the following physicochemical parameters: Calculated: Content: 23.99 23.88 nitrogen,% The content of primary amino groups in terms of nitrogen,% 5, 33 Viscosity at, Pa-s 79.6 Compound (V) can be obtained in a technically pure form by condensation of the starting imidazoline with U11-606 / 2 at a molar ratio of 3: 1, However, such an imidazoline compound is poorly soluble in common organic solvents, has a softening temperature of 150-160 and in a molten state It is a viscous substance, Therefore, CH2 CH2NH2 (compound (V ) in pure form is much less effective as a hardener of cold bore, than a mixture of compounds (III), (IV) and (V), B. Curing of epoxy composition, Preparing a mixture of 600 May, h, epoxy resin ED-22 with epoxy content groups of 23.2% and 60 mAh of butylglycidyl ether (resin EDB / 6 /), 329.9 mAh, synthesized in section B, imidazoline hardener. thoroughly mixed with 660 may, h, EDV tar, air bubbles are removed in a vacuum cabinet with a residual pressure of 3 mm Hg, Art. The epoxy composition obtained is poured into preformed metal molds for making standard specimens. Half of the standard specimens are cured for 15 days at room temperature, the other half within 24. hours at room temperature and 5 hours at 80 s. At the same time, a resin of EDB is being cured (330 parts by weight) with a mixture of HjN-CH2CH2NV. The resulting product is a viscous, noncritrimally liquid with the following physicochemical conditions: Found Calculate Molecular 476 mass Content,% hydrogen carbon (CH2 jg - V- CHz CH IIHCH - CH, NCH, CHzNH,., ("I) 24.67 25.77 Nitros 0.88 Acid Viscosity at 25 ° C, mPa-s 4960 - Density at 25 ° C, g / cm 1 , 12 The refractive index of p 1,5249. Synthesis of the target imidazoline hardener

112657010

According to Example 1, B. B out of 85.6 g of compounds (VII) and 46.8 g (0.17 mol) of 2,4,6-tris (dimethylaminomethyl) -resorcinol, 508.4 g (99.8% of

theoretical) dark colored viscous product, representing a mixture of compound (VII) with a substance of the formula.

2fe 82 -CH2m2N - v-CHV. The molar ratio of the divisions (VII) is calculated: (VIII) 1: 1. The resulting hardener has the following physicochemical properties. Calculated content 24.54 nitrogen,% 24.72 Content of primary amino groups in terms of nitrogen,% 4.21 Viscosity at 40 ° С, Pa s Curing with an epoxy composite based on a synthesized hole. Under the conditions of Example 1, p. B out of 660 g of EDB resin and 342 g of synthesized

i7H5Jg5r-N-CH2CH2KHCH2 SNGSch

V C | rHj2 r-lf-CHjCHjNHCHiCH iT The molar ratio of compounds (IX) :( X) is approximately 1; 1 (calculated from the ratio of the starting components). Imidazoline hardener has the following physico-chemical characteristics:

W CH2CH.N- (CHzje-TrN-CHiCH NHCHzCH-N-CHzCHol Hj CH2NHGH2CH2K- {CH2) 8-7r-N-CH2CH2llH2 bath curing agent prepares the epoxy composition and cures it cold (composition 7) and hot (composition 8) modes. In tab. 3 shows the properties of polymeric materials based on epoxy compositions. 7 and 8. Example4. Synthesis of the original imidazoline hardener. Under the conditions of example 1, out of 926 g (1 mol) methyl esters of fatty acids of soybean oil, 146 g (1 mol) of triethylene tetramine and 50 g (0.5 mol) of methyl methacrylate additionally added and 53 g (0.5 mol) of diethylenetriamine, 456 are obtained , 6 (96.8% of theoretical) low viscosity non-crystallizing dark-colored product, which consists of two compounds of the formula jCH-; rN-CH2CH2NH NS Found Calculated Molecules p467, 5 per weight 506%, carbon 72.01 of hydrogen 10.96 nitrogen 15.90

oxygen Viscosity at mPa s Density at, g / cm

Synthesis of target imidazoline hardener.

1126570

12

Under the conditions of example 1, p. B out of 456.6 g of synthesized hardener and 59.4 g (0.13 mol) of 3.3.5, 5 -tetrakis (dimethylaminomethyl) -diphenylolpropane-2, 2 (UP-0628) 486.2 g (98.7% of theoretical) of a viscous product is obtained, which is a mixture of the starting imidazoline (Compound (IX) and (X) and compounds of the general formula

ZO6 Rj - CH2CH2NHCH2CH2iN - or -CH-CHjN-CHO The molar ratio of compounds (IX) and (X) in total to compounds (XI) is 3: 2. The synthesized target curing agent has the following indicators: Content Calculated nitrogen,% 14.28 14.04 The content of primary amino groups in terms of nitrogen, 7, 1.70 Viscosity at -40 s, Curing by epoxy composites based on synthesized hardened bodies. 1 p. Out of 660 g of EDB resin and 414 g of synthesized hardener, an epoxy composition is prepared and cured in cold (composition 9) and hot (composition 10) modes. In tab. 4 shows the properties of polymeric materials based on epoxy compositions 9 and 10. Example 5 Synthesis of Soybean Oil Methyl Oligomeric Acids.

GH NHCHzCH NHCHiCHgK- С „Hjz V A four-necked flask equipped with a thermometer, barbater for inert gas and a reflux condenser is charged with 400 g of methyl fatty acids obtained by methanolysis of soybean oil, 24 g of clay kil with a pH of a water extract of 7.5.8 g water and 0.88 g lithium carbonate. The reactor, the ionic mixture is heated under nitrogen and heated to 8 hours at this temperature. The reaction mass is then cooled until 5 g of phosphoric acid are injected to destroy the fine dispersion of clay, neutralize the lithium soaps and extract the iron oxides, keep it at temperature for 3 hours, then filtered on a funnel for hot filtration. The unconverted monomer esters are distilled off in vacuo at a residual pressure of 57 mm Hg. and the vapor temperature 220240 0. 220 g (55% of the mass of the load) of methyl esters of oligomeric fatty acids of soybean oil are obtained in the form of a viscous dark-colored liquid 13 with the following physicochemical indicators: Acid 5-8 mg KOH / mg. KOH / g Number of saponifiers or MGKON / G 165-175 mg CO. Water number g 95-105 g 1/1 Refractive index 1.4815 Molecular mass (cryoscopy in benzene) 580-620 Synthesis of initial imidazoline hardener. In a round-bottomed four-necked flask equipped with a thermometer, a stirrer, a barbaterom for the supply of an inignant gas and a distillation column connected to a direct chill, 220 g of methyl esters of oligomeric soybean oil, 74 g (1.08 equivalent per 1 equivalent) are sequentially loaded. ether groups) diethylenetriamine and, additionally, 4.3 g (0.05 mol) of methylac lat and 5.2 g (0.05 mol) of diethylene triamine. The reaction mixture is heated to 120-140 ° С. simultaneously inert gas passes, and the methanol produced by the reaction is distilled off. After the main part of methanol is distilled off (80-85% of the theoretical possible), the reaction mass is gradually heated to 250 ° C, and the residual amount of methanol and reaction water is held at 250-260 ° C. until complete cessation of the shoulder strap. An imidazoline hardener is obtained in the form of a complex mixture of compounds with the following physicochemical indicators: Molecular. mass,% 784 Content of nitrogen titrated,% 7.85. including primary amino groups 3.64 secondary amino groups 0.45 Viscosity at 25 ° C mPa s8560 Density at 25 ° C, g / cm. 1.04 Synthesized imidazoline is used to obtain the desired imidazoline hardener. Synthesis of target imidazolinog hardener. Under the conditions of example 1 p., From 258 g of the starting imidazoline hardener and 5.6 g (0.021 mol) of 2-dimethylaminomethylphenol, 261.2 g (99.7% of theoretical) of a viscous dark colored product are obtained, with the following physicochemical parameters mi Content is calculated nitrogen,% 10.98 10.85 Content of the primary. amino groups in nitrogen content,% 3.63 3.46 Viscosity at 40 ° C, Pa-s 12.6 Curing of an epoxy composition based on a synthesized hardener Under the conditions of example 1 p. Of 660 g of EDB resin and 626.4 g of synthesized The hardener prepares the epoxy composition and cures it in a cold (composition 11) and hot (composition 12) mode. In tab. 5 shows the properties of polymeric materials based on epoxy compositions 11 and 12. Example 6. Synthesis of methyl esters of a mixture of monomeric and oligomeric fatty acids of flaxseed oil. Under the conditions of Example 5, 300 g of methyl esters of fatty acids obtained from the methanolysis of linseed oil will be polymerized. The polymerization is carried out in the presence of 18 g of clay, with a pH of a water extract of 7.5.6 g of water and 0.66 g of lithium carbonate. After treating the polymer with phosphoric acid, filtering and distilling highly volatile materials (up to 150 ° C in weight at 5–7 mm Hg), 280 g of a mixture of methyl esters of monomeric and oligomeric acids of flax oil are obtained. Physico-chemical properties of the esters obtained: Acid number, mg KOH / G16-19 The saponification number, mg KOH / G180-188. Iodic number by the method of Wiisa,. g 1 / 100148-155 Content of monomeric acids,% 43-45

15

Synthesis of the original imidazolinog hardener,

Under the conditions of Example 1 p. A, out of 280 g (0.45 g-eq) of polymerized methyl spirin oil, 94 g (0.9 mol) of d-ethyl triamine, and 96.6 (0.2 mol ) 2-phenylacrylic acid and 20.6 g (0.2 mol) of diethylenetriamine, 341.8 g (98.5% of the theoretical) of the starting imidazoline curing agent are obtained in the form of a complex mixture of compounds with the following physicochemical indicators: Molecular weight 845 The content of nitrogen titrated,%. 8.06 including primary amino groups 3.82 secondary amino groups 0.8 Viscosity at, mPa-s; 1430

Density at 25s, g / cm3,04

Synthesis of target imidazoline hardener

Under the conditions of Example 1, p. B out of 341.8 g of an imidazoline hardening agent and 20.8 g (0.078 mol)

Destructive stress, kgf / cm

bending

under compression

when stretched

Elongation at

disintegration,%

.

Impact viscosity, kgf cm / cm Heat resistance VIC a, C

Gel time at, min

2657016.,

hardeners U1T-606/2 receive 350.4 g (99.5% of theoretical) of a dark-colored viscous product with the following physicochemical 5 Properties:.

Content

Nitrogen TIT- Calculated

ruled% 9.2 7.93

Content 10 primary

amino groups

In terms of

3.38 per nitrogen,%

3.67 Viscosity at,

38.6 Pa-s

Curing of epoxy composition based on synthesized imidazoline hardener. 0 Under the conditions of example 1 p. B, a composition of 330 mas is prepared. EDB and 297 ma.ch. synthesized imidazoline hardener. The epoxy composition is cured in a cold (composition 13) and hot (composition 14) mode.

The properties of the polymeric materials thus obtained are given in Table. 6

T and b and ij and J.

874 ± 102

1100 + 49

880 ± 55

1088 ± 28

437 + 88

658 + 43

47

Properties Destructive stress, kgf / cm: during bending under compression under tension Relative elongation at break,% Intensity of viscosity, kgf-cm / cm 15.7 ± 3.3 Heat resistance according to ViCa, C 128 Time of gelatinization at 25 C, min ;; I Properties ... „„ „.., J Destructive stress, kgf / cm: during bending under compression under tension Relative elongation at break,% Shock viscosity, kg-cm / cm Heat resistance according to VIC, C Gel time At 25 ° C, min. Properties. - Destructive stress, kgf / cm: during bending under compression under tension Relative elongation at break,% Impact viscosity, kg-cm / Heat resistance according to VIC, C Gel time at, min

T.a.6.JLJlJL a.2 ..

The performance properties in the composition are 994 ± 41 1118t31 521 + 44 4.3 ± 1.8 643 ± 84 084 + 35 846 ± 63 194 ± 29 390 ± 74 567 ± 45 4.6 + 1.2 1.9 ± 1.3 668 + 2.9 7.9t4.0 134 66. and csa 3 Indicators of properties in compositions g- 1148 + 64. 1203 + 39 1096 ± 37.1188 ± 49 608 + 56624 + 24 4.8 + 1.94.9 + 1.4 17.0 + 3.1.18.5 + 3.5 158164 126 Table4 Property measures in compositions 1 910 964+ 51. 994 ± 51 906 + 32935 + 45 484 + 30496 + 38 6.9 ± 2.07.3 ± 1.8 15.3 ± 4.416.9 + 4.2 8894 260 19

Properties

Destructive stress, kgf / cm under bending under compression when stretched,

Relative elongation at break, / Impact-viscosity, kg “cm / cm Heat resistance by VIC, € Gelding time at 25 ° С, min

Destructive stress, kgf / cm

bending988 + 32

compressive927 + 24

when stretched 503 + 49

Elongation at break, 6.6 + 2.5

Impact viscosity, kg.cm / cm 16.7 + 4.3

Heat resistance VIC, C78

Gelatinization time at min 300

20

..

properties in the composition

Indicators

lEZZfZZ 11

1034 ± 38

1093 ± 49

602 ± 34

8.8 + 4.0 16.7 + 4.1 117

990 + 46 956 + 30 538 ± 37

7.2 + 3.0 17.0 + 06.2 82

Claims (1)

(54X57) METHOD FOR PRODUCING IMIDAZOLINE HARDENERS OF EPOXY RESIN. condensation of mono-, di- and / or polycarboxylic acids with polyamines of an ethylene series of the formula Η ^ Νί-ΟΗ ^ Ι ^ ΝΗ ^ -Η, where η = 1-10, with the addition of equimolar amounts of οί, ρ-unsaturated acid and polyamine of the specified formula with a ratio of carboxylic acid and βί, / e-unsaturated acid from 10: 1 to 10:13 at 120-280 ° C, characterized in that, in order to increase the reactivity of the hardeners at room temperature, the resulting imidazoline hardener is additionally condensed with a Mannich mono- or poly-acid base at 100-150 ° C with a molar ratio of imidazoline hardener and base Mannich from 2: 1 to 10: 1. 1 1126570