KR900004221B1 - Process for the preparation of bis-maleimide resin - Google Patents

Abstract

A modified bismaleimide resin is prepd. by Michael addition reaction of bismaleimide and aromatic secodary diamine at 100140 C. Pref. the mole ratio of the bismaleimideto aromatic secondary diamine is 1.2:1- 4.0:1. Pref. the bismaleimide is N,N'-1,3phenylene bismaleimide, N,N'-4,4'-diphenylmethane bismaleimide, N, N'-4,4'-diphenylsulphone bismaleimide, etc.. Pref. the aromatic secondary diamine is N,N'- dimethyl-4,4'-diamino diphenyl methane, N,N'-dimethyl-2,4-diamino toluene, or N,N'-dimethyl-2,6-diamino toluene, etc..

Description

Method for producing modified bismaleimido resin

The present invention relates to a method for producing a modified bismaleimide resin, and more particularly, to a modified bismaleimide resin oligomer obtained by Michael addition reaction of bismaleimide with an aromatic secondary diamine. It relates to a manufacturing method.

As is well known, reactive oligomers are low molecular weight intermediates having the properties of fully cured resins in thermosetting resins, which are excellent in thermal stability, but are very poor in processability for use as structural materials. It was introduced for.

Bismaleimide resins are all formed in the oligomer state, and when cured according to the backbone structure and molecular weight of the oligomer, the bismaleimide resin has a great influence on thermal and mechanical properties, and also has a great influence on the molding conditions.

Currently, bismaleimide resins have excellent properties such as excellent long-term thermal oxidation stability, high temperature wet-wet strength, dimensional stability, flame retardancy, and low water absorption rate, and are relatively inexpensive and easy to process. As a matrix resin of advanced composite materials in high-tech industries such as aerospace and defense industries, it is complex in all industries requiring heat resistance such as electronics, automobiles, and general industries. It is an excellent heat resistant resin that is used as a base material.

In general, resins made by copolymerizing only bismaleimide itself have a high cross-linking density, so the heat resistance is very high (Tg is higher than 300 ° C.), while very brittle and high boiling point is achieved. N-methyl-2-pyrrolidone (NMP, bp202 ℃) and N, N'- dimethylformamide (DMF.bp153 ℃), such as polar solvents are soluble only.

When prepreg is made by impregnating carbon fiber with a high boiling point polar solvent, it is difficult to remove the solvent, so it has a high residual solvent amount, and when it is laminated, the residual solvent acts as a plasticizer. This becomes a factor which reduces the physical property of resin.

Kerimid 601 resin, developed by Rhone-Poulence, a representative bismaleimide resin that is currently commercialized, is a bismaleimide 4,4-bismaleimide diphenyl methane and a primary diamine methylene. It is a reactive oligomer which has a molecular weight of about 1000 synthesized by Michael addition reaction of dianiline and is terminated with maleimide group.

In this case, the diamine is added to bismaleimide to increase the molecular weight of the oligomer, and as a result, the crosslinking density is lowered when it is cured, so that the heat resistance is somewhat lowered, but it has some toughness.

On the other hand, if the amount of diamine is too large, degradation occurs easily at high temperatures, making it ineffective as a heat resistant resin.

The Keremido 601 resin developed by Long-Fran succeeded in overcoming these conflicting properties and commercializing by finding an appropriate ratio (molar ratio of 2.5: 1) of bismaleimide and primary diamine.

However, Carimido 601 resin can only be used as a base material for multilayer printed circuit engines in the electronics industry due to the disadvantage of using N-methyl-2-pyrrolidone, a high boiling point polar solvent.

This is because bismaleimide diamine is Michael addition reaction at low temperature to form a low molecular weight oligomer, and when crosslinked by diamine as well as self-reaction of double bond of bismaleimide which is terminal group when cured at high temperature The crosslinking reaction also occurs simultaneously, resulting in a high crosslinking density.

In the present invention, by using bismaleimide and secondary diamine to solve such problems, the pot-life is greatly improved by eliminating the disadvantage that the cross-linking reaction proceeds during the Michael addition reaction at a low temperature and the viscosity increases rapidly. Could.

Here, puttrafra refers to the maximum time that hardening does not occur when a curing agent is mixed with a liquid thermosetting resin, and a high boiling point polar solvent, as well as a high temperature melting process (no solvent) are used. There is an advantage that this is possible.

When prepreg is manufactured by using a high temperature melting process, the physical properties of the final composite material are not impaired because no volatiles are generated at all except economical and processing advantages of using no solvent. That is, the present invention relates to a method for producing modified bismaleimide resin, characterized by Michael addition reaction of bismaleimide and aromatic secondary diamine at a temperature of 100-140 ° C.

Hereinafter, the present invention will be described in detail.

Bismaleimide used in the present invention is a substance represented by the following general formula (I).

Compounds of general formula (I) are specifically for example N, N'-1,3-phenylene bismaleimide, N, N'-4,4'-diphenylmethane bismaleimide, N, N'- 4,4'-diphenylether bismaleimide, N, N'-4,4'-diphenyl sulfone bismaleimide, N, N'-3,4'-diphenylsulfon bismaleimide, N, N ' -4,4'-dicyclohexylethanebismaleimide, N, N'-4,4'-dimethylenecyclohexanebismaleimide, N, N '.- 4,4'-diphenylcyclohexane bismaleimide , N, N'-1,3-xylylene bismaleimide, 2,4-bismaleimide toluene, 2,6-bismaleimide toluene and the like are suitable.

The secondary diamine used in the present invention is a substance represented by the following general formula (II).

Where Ar 'is an aromatic group and R is an aliphatic group

Compounds of formula (II) are specifically for example N, N'-dimethyl-4,4'-diamino diphenylmethane, N, N'-methylenyl-4,4'-diamino diphenylmethane , N, N'-dimethyl-4,4'-diaminodiphenylsulfone, N, N'-diphenyl-4,4-diaminodiphenylether, N- (1,3-dimethylbutyl) -N ' -Phenyl-paraphenylene diamine, N-isopropyl-N'-phenyl-paraphenylene diamine, N, N'-diphenyl-paraphenylene diamine N, N'-dimethyl-2,4-diamino toluene, N, N'-dimethyl-2,6-diamino toluene and the like are suitable.

In addition, the molar ratio of bismaleimide and secondary diamine is used as 1.2: 1-4.0: 1, Preferably it is 2: 1-3: 1.

When the amount of the secondary diamine is used in the above range or less, the crosslinking density becomes low and the heat resistance is lowered. When the amount of the secondary diamine is used in the above range, the heat resistance is high but the toughness is low.

Hereinafter, the present invention will be described in detail by way of examples.

Example 1

10.8 g N, N'-dimethyl-4,4'-diamino diphenyl methane (1mo1) and 42.9 g N, N'-4,4'-diphenyl methane in a three-necked flask equipped with a stirrer and thermometer Bismaleimide (2,5mo1) is added.

Subsequently, 130 ℃ was maintained while stirring with a stirrer to react for about 10 minutes to confirm that the clear solution, poured into an aluminum dish, cooled to room temperature and then pulverized in a mortar to obtain a yellowish brown glossy powder.

Using the PMS (Rheometrics Mechanical Spectromter) model 605, and poured into a parallel plate (Paral1el Plate) and trimming (Trimming), the foot life was analyzed by measuring the viscosity change over time while heating at 130 ℃ in the dynamic mode.

The results are shown in Table 1.

Comparative Example 1

After 9.5 g of methylene dianiline (1mo1) was maintained at 120 ° C, 42.9 g of N, N'-4,4'-diphenylmethane bismaleimide (2.5 mol) was added and reacted for about 5 minutes. The same results as in Example 1 were shown in Table 1 below.

Comparative Example 2

4.5 g of N, N'-diethyl-4,4'-diamino diphenyl methane (0.5 mo1) and 3.9 g of methylene dianiline (0.5 mo1) were mixed and maintained at about 130 ° C., followed by 35.8 g of N Except for reacting for about 10 minutes by addition of N'-4,4'-diphenylmethane bismaleimide (2.5 mol) was carried out in the same manner as in Example 1 and the results are shown in Table 1.

TABLE 1

Comparison: The lower the bund, the better the moldability.

Claims (4)

A method for producing a modified bismaleimide resin, characterized in that Michael addition reaction of bismaleimide and aromatic secondary diamine at a temperature of 100-140 ° C. The bismaleimide of claim 1, wherein the bismaleimide is N, N'-1,3-phenylene bismaleimide, N, N'-4,4'-diphenylmethane bismaleimide, N, N'-4,4 '-Diphenylether bismaleimide, N, N'-4,4'-diphenylsulfone bismaleimide, N, N'-3,4-diphenylsulfone bismaleimide, N, N'-4,4 Dicyclohexylmethane bismaleimide, N, N'-4,4'-dimethylene cyclohexane bismaleimide, N, N'-4,4'-diphenyl cyclohexane bismaleimide, N, N'- A method for producing a modified bismaleimide resin, characterized in that any one of 1,3-xylene bismaleimide, 2,4-bismaleimide toluene, 2,6-bismaleimide toluene. The method of claim 1, wherein the aromatic secondary diamine is N, N'-dimethyl-4,4'-diamino diphenyl methane, N, N'-dimethylethyl-4,4'-diamino diphenyl methane, N, N '-Dimethyl-4,4'-diamino diphenyl sulfone, N, N'-dimethyl-4,4'-diamino diphenyl ether, N- (1,3-dimethyl butyl) -N'-phenyl- Para phenylene diamine, N-isopropyl-N'-phenyl-paraphenylene diamine, N, N'-diphenyl-paraphenyllian diamine, N, N'-dimethyl-2,4-diamino toluene, N, A method for producing a modified bismaleimide resin, characterized in that any one of N'-diethyl-2,6-diamino toluene. The method for producing a modified bismaleimide resin according to claim 1, wherein the molar ratio of bismaleimide and aromatic secondary diamine is 1.2: 1 -4.0: 1.