DE1301135B - Process for the production of molded articles - Google Patents

Description

1 2

It is known that mixtures containing epoxy compounds 4 - methylimidazole, 2 - cyclohexyl - 4 - methylimidazole, and aliphatic amines, fairly quickly 2-octyl-4-hexylimidazole and mixtures thereof, react, so that it is necessary, the components. A particularly preferred liquid imidazole is that mix 2-ethyl-4-methylimidazole with each other shortly before use.

and then to use the mixture quickly before 5 used in the method of the invention the reaction begins. Such a procedure is used for those forming the base of the shaped bodies Of course, means a significant load and epoxy compounds those that on average more also leads in many cases to deficient than an epoxy group, i. H. a ^ j

Products, especially if they are not properly mixed '"^

the components and too rapid processing of the io '

Mixtures. The processability or ^ \ _{r n}

Consistency of the mixtures through the use of ^ ^ group,

aromatic amines must be extended, however
then a significantly higher temperature at the

Implementation will be applied. For many uses, 15 per molecule included. The number of on average The purpose of the epoxy compounds is to obtain a high reactivity in the molecule of epoxy groups, tion temperature undesirable, for example when winding if you consider the average molecular weight of the epoxy Threads, when encapsulating, etc. It therefore appeared connection divided by the epoxy equivalent weight, desirable as reaction components stick- The epoxy compounds can known to use substance-containing compounds that have been saturated or unsaturated for a long time, aliphatic, cycloaliphatic, Ensure "pot stability" and at the same time be aromatic or heterocyclic as well as appropriate high reaction temperatures for the formation of substituents, if any, which are not involved in the reaction Products with good physical properties, such as halogen atoms, hydroxyl groups, to lead. Ethereal remnants and the like

The invention relates to a process for 35 Preferred epoxy compounds are glycidyl ethers Production of moldings or sheet-like structures of polyhydric phenols, e.g. B. Diphenylolalkanes, on the basis of polyadducts by reacting, for example, diphenylolpropane, diphenylolethane and Epoxy compounds that contain more than one epoxy group Diphenylolmethane, Diphenylolsulfon, Hydroquinone, contained in the molecule, contained with amino nitrogen - resorcinol, dihydroxydiphenyl, dihydroxynaphthalene, the compounds, and is characterized by 30 or polyhydric phenols, such as novolaks and resols, that as nitrogen-containing compounds are liquid by the condensation of phenol and formaldehyde Imidazoles of the formula are made. Most suitable are glycidyl

polyether of 2,2-bis- (4-hydroxyphenyl) -propane with

X ₁ c N has a molecular weight between 340 and 4000.

:> ρ 35 Other useful epoxy compounds are poly-

TTQ Q χ epoxyalkyl ethers of aliphatic polyhydroxy compounds

\ vj / ² fertilize, such as ethylene glycol, glycerine and tri-

TT methylolpropane; Polyepoxyalkyl esters of polybasic

rule carboxylic acids, e.g. B. the diglycidyl esters of phthalic acid, terephthalic acid and adipic acid, and

in which X ₁ and X ₂ both represent aliphatic hydrocarbon polyglycidyl esters of polymeric unsaturated fatty residues with 1 to 8 carbon atoms, acids are used, for example the diglycidyl ester of the dimeric acid. acidified linoleic acid; epoxidized esters of unsaturated

The mixtures of epoxy compounds with more acids, e.g. B. epoxidized linseed oil or soybean oil; imidazolated vinylcyclohexane to be used as an epoxy group in the molecule and the dienes epoxidized in the invention, such as diepoxybutane and processes according to the epoxidation; Diepoxyalkyläther, in which compounds have two epoxyalkyl groups on only one oxygen atom at a lower temperature, have a relatively good shelf life and can be bonded to, such as diglycidyl ethers; and polyepoxy very resistant cross-linked moldings re-compounds, which are obtained by epoxidation of cyclo-setting, if they are at moderately high temperatures, about 50 hexene derivatives, such as. B. the 50 ⁰ C and above, are heated. This advantage is (3,4 - epoxy - 6 - methylcyclohexyl) - methyl ester which is particularly desirable in applications where a good S ^ -epoxy-δ-methyl-cyclohexanecarboxylic acid. Resistance of the mixtures necessary, a high The quantitative ratio between epoxy compound

Conversely, reaction temperature is undesirable, as and imidazole compound can be within a wide range for example, fluctuate in the formation of casting compounds for 55 areas. They react particularly well certain electrical apparatus, when winding products when the imidazole compound in a of threads, when applying coatings to an amount of 0.1 to 50 percent by weight of the epoxy foam products, in the production of coatings compound, even better when they are in a quantity of for certain military or engineering applications, 5 to 30 percent by weight of the epoxy compound armor and the like 60 is used.

Another advantage of the compounds according to the invention The imidazole can be in per se

Process obtainable molded body is that known way together with others for the they were excellent despite the reaction at moderate temperature epoxy polyadduct formation have physical properties, use components, e.g. B. with phenols, mercapdies tanen, triphenylphosphine, triphenylarsine, triphenyl prove themselves especially at an elevated temperature. stibine, amines, amine salts and quaternary ammo

Examples of the sodium salts to be used according to the invention. Imidazole compounds are, inter alia, 2-ethyl examples of suitable and for the mentioned

Purpose known amines which can be used together with the imidazole compounds are Benzyldimethylamine, dicyandiamide, p, p'-bis (dimethylaminophenyl) methane, Dimethylethanolamine, morpholine, dimethylaminopropylamine, metaphenylenediamine, Polyalkylene polyamines such as diethylenetriamine and mixtures of the above mentioned amines. the Salts can be formed from an inorganic or organic acid and an amine, such as the hydrochlorides, the sulfates and the acetates of the tertiary amines described above. examples for quaternary compounds are: benzyltrimethylammonium chloride, phenyltributylammonium chloride, cyclohexyltributylammonium sulfate, Benzyl trimethyl ammonium sulfate, benzyl trimethyl ammonium borate, diphenyl dioctyl ammonium chloride and mixtures thereof.

These additional amines can be used in a manner known per se in amounts of 0.1 to 25 percent by weight, preferably from 1 to 5 percent by weight, based on the epoxy compounds, can be used.

The reaction is complete after mixing the epoxy compound with the imidazole compound Heating the mixture thus obtained causes. The mixture can be different before the implementation known additives are added, such as solvents, diluents, pigments, fillers, fibrous Products, dyes, resins, plasticizers and non-volatile extenders. Is the epoxy compound or the imidazole compound is a relatively viscous liquid or solid substance, then you can heat the components while mixing them or use a solvent, e.g. B. benzene, Toluene, cyclohexane, ketones, ethers, esters, nitriles.

Furthermore, monoepoxy diluents can be used in a manner known per se, such as Butyl glycidyl ether, phenyl glycidyl ether and monoglycidyl ester. Take monoepoxy thinner participate in the reaction and can generally in amounts of up to 20 percent by weight of the epoxy compound be used. Inert, non-volatile extenders can also be used, such as Coal tar, coal tar pitch, asphalt, pine pitch, turpentine oil, lubricating oil fractions and their aromatic Extracts, as well as refined lubricating oils.

The applicable during the reaction temperature can vary within a wide range and is generally between about 40 and 300 ⁰ C, preferably between 50 and 25O ⁰ C.

The moldings obtained by the process according to the invention have a surprisingly high level Dimensional stability in the heat and very good strength properties even at elevated temperatures. They also show great durability to boiling water and strong solvents and other chemicals. These Unusual properties make the process according to the invention particularly valuable for production of adhesive bonds, laminates and other molded articles, such as encapsulation of electrical components Equipment according to methods known per se.

The great advantage of being used as reaction components in the process according to the invention Imidazole is based on the fact that the masses prepared with it at a moderately high temperature Reaction can be brought, so that when using them no adverse effects on the heat-sensitive material to which they are applied is to be feared.

The invention is illustrated in more detail by the following examples. The parts mentioned therein are parts by weight. The epoxy compounds A, B and C are polyglycidyl ethers of 2,2-bis (4-hydroxyphenyl) propane with the following characteristics.

Epoxy equivalent

Molecular weight

Viscosity (Poises 25 ° C)

Melting point (Durran) ⁰ C ...

example 1

Epoxy compounds

AtBIC

200 380 150

250 483

27 I 52

There were ^ 100 parts of epoxy compound A combined with 10 parts of 2-ethyl-4-methylimidazole. At room temperature, this mixture had a pot life of more than 8 hours. A portion of the mixture reacted at 60 ° C for 8 hours was converted into a hard, insoluble, infusible molding having excellent heat distortion temperature (HVT), hardness, strength and chemical resistance. The heat distortion temperature and strength values are given in Table 1 below under (A) in comparison with the HVT and strength values of comparable preparations (B) and (C) which were produced using known and customary conversion components. The mixture (B) containing 100 parts epoxy compound A and 14.3 parts of m-phenylenediamine and was reacted for 2 hours at 8O ⁰ C and for an additional 2 hours at 15O ⁰ C. The mixture (C) containing 100 parts epoxy compound A and 12 parts of tri (2-ethylhexanoic acid) salt of tri (dimethylaminoäthylphenol) and was reacted at 6O ⁰ C in the course of 8 hours for reaction.

Table 1 By S Add
(A) immensetzi
(B) mg
(C) 110
882
350 150
931
539 67
777 HVT, ⁰ C ..... 32,200
10,500 30,800
21,000 35,000 Maximum tensile strength,
kg / cm ²
23 ° C game 2 100 ⁰ C Tensile modulus, kg / cm ²
23 ° C 100 ° C

100 parts of epoxy compound A were combined with 10 parts of 2-ethyl-4-methylimidazole and the obtained mixture used for winding threads. Here, glass fibers were added to the mixture dipped, pulled through it and then wound on a mandrel to form the belt. The product obtained was reacted at 60 ° C. for 8 hours. The epoxy-polyadduct content was 15%

The following table 2 lists some properties of the product obtained under (A) in comparison

shown equal to the properties of a comparable product (B), which is made from the mixture (B) prepared according to Example 1 (epoxy compound A and m-phenylenediamine) and like the mixture from Example 1 had been brought to implementation.

Table 2

2-ethyl-4-methylimidazole mixed. This mixture was ^{heated to 70 °} C. for several hours. In this way, too, hard, insoluble, non-meltable moldings which had good properties at high temperature were obtained.

Example 6

system
(A) I (B)

20,300 455,000

637
322

Tensile strength, maximum kg / cm ²

23 ° C 14,000

Glass load, maximum kg / cm ²

23 ⁰ C 21.700

Tensile modulus, kg / cm ² 448,000

Horizontal thrust

Strength, kg / cm ²

23 ° C 644

150 ⁰ C 462

Example 3

100 parts of epoxy compound A were combined with 10 parts of 2-butyl-4-ethylimidazole and that obtained mixture kept at 60 ° C for several hours. The with the appropriate shape The structures obtained were hard, insoluble and not meltable and had particularly good properties at high temperature.

If in Example 1 the epoxy compound A ίο was replaced by a mixture of equal parts of the epoxy compound A and S ^ epoxy-o-methylcyclohexyl-S ^ -epoxy-6-methylcyclohexanecarboxylate, similar 14,700 satisfactory results were obtained.

Example 4

* 5 Example 7

Also a reworking of Examples 1 to 3, but with 2,4-dioctylimidazole as the reaction component was used, gave results which also corresponded to those of Examples 1 to 3.

Claims (2)

Patent claims: 1. Process for the production of moldings or sheet-like structures based on polyadducts by reacting epoxy compounds that contain more than one epoxy group in the molecule with amino nitrogen-containing compounds, characterized in that the nitrogen-containing compounds are liquid imidazoles of the formula 30th Replaced in Examples 1 and 2, the epoxy compound A by an equivalent amount of Epoxy compounds B and C, similar results could be obtained. X ₁ -C- -N t! .CX ₂ Example 5 There were 100 parts of a glycidyl ether of a novolac resin, which is produced by the reaction of a condensation product obtained from phenol and formaldehyde with epichlorohydrin, with 15 parts 40 in which Xi and X ₂ both represent hydrocarbon radicals with 1 to 8 carbon atoms can be used. 2. The method according to claim 1, characterized in that that the imidazole compound 2-ethyl-4-methylimidazole is.