JPH07278264A - New polyglycidyl ether and flame-retardant epoxy resin composition containing same - Google Patents

Abstract

PURPOSE:To obtain a flame-retardant epoxy resin compsn. which is excellent in flame retardance though it does not contain or hardly contains a halogen and which is esp. suitable for electric and electronic applications by compounding an epoxy resin contg. no phosphorus, a polyglycidyl ether contg. phoshporus, and a curative. CONSTITUTION:This flame-retardant epoxy resin compsn. contains at least one epoxy resin contg. no phosphorus, a polyglycidyl ether of the formula (m is 2 or 3; n is 0 or 1 provided m+n is 3; R<1> is optionally branched 1-6C alkyl, alicyclic, or arom.; R<2> and R<3> are each H or 1-4C linear alkyl; R<4> is H, 1-4C linear alkyl, or arom.; and R<5> is H or CH3), and a curative. This compsn. is prepd. by mixing the foregoing ingredients by publicly a known method and is not only esp. suitable for electric and electronic applications but also suitable for other applications, such as coating materials, adhesives, and flooring.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a phosphorus-containing polyglycidyl ether compound, a process for producing the same, a curable flame-retardant epoxy resin composition containing at least one of the phosphorus-containing polyglycidyl ether compounds, and a composition thereof. The present invention relates to a manufacturing method, an article containing the composition in a cured state, particularly a printed wiring board.

[0002]

Epoxy resin compositions are commonly used in the electronics and electrical industries. Typical examples thereof are printed wiring boards (formerly called printed circuit boards), electrocasting and potting, and the use of semiconductors in encapsulants. In these application areas, the epoxy resin composition is required to have not only an excellent combination of mechanical, electrical and physical properties, but also a high degree of durability and flame retardancy. To date, the most commonly used flame retardant epoxy resin compositions suitable for use in the manufacture of laminates, especially for printed wiring boards, are conventional brominating compounds such as tetrabromodiphenylolpropane. It was based on epoxy resins, or epoxy resins obtained by the reaction of liquid epoxy resins with tetrabromodiphenylolpropane, curing agents such as dicyandiamide and accelerators such as imidazole. In these compositions, the bromine is about 10-25 per total composition.
Flame Retardancy Test Method UL 94, when present in an amount of wt%
The desired flame retardancy level of V = 0 rating by V is obtained. The environmental downsides associated with halogen-containing compositions are the same as long as the other physical / electrical and mechanical properties of the epoxy resin composition are at the levels required for these applications. It triggered the search for alternative flame-retardant epoxy resin compositions with very low halogen content at the flammability level.

Such flame retardant epoxy resin compositions are disclosed in US Pat. No. 4,345,059, which relates to epoxy resin compositions containing 3-hydroxyalkylphosphine oxide as a flame retardant.
However, the composition has a number of drawbacks. First, the 3-hydroxyalkylphosphine oxide is
Often poorly soluble in epoxy resin monomers, and therefore, in the formulation of the resin or in the resin to obtain a uniform blend, a strong organic solvent such as dimethylsulfoxide,
Dimethylformamide or halogenated solvents must be used. This involves an extra step in the preparation of the epoxy resin composition, and the use of organic solvents is becoming increasingly unacceptable from an environmental point of view. Second, since the 3-hydroxyalkylphosphine oxides are not normally reactive under the conditions of conventional epoxy resin curing processes, such as those applied in printed wiring board manufacturing, the oxides are at the end of the curing cycle in the resin matrix. It will not chemically bond with and will be incorporated therein as an inert additive that does not. This entails the risk of leaching of phosphine oxide from the cured resin composition, which sometimes leads to reduced flame retardancy. Furthermore, the presence of inert additives deteriorates the overall properties of the cured resin.

US Pat. No. 4,345,059 discloses 3-
A possible solution to this problem has been provided by pre-reacting the hydroxyalkylphosphine oxide and the anhydride compound at a temperature of 70-120 ° C. before compounding with the epoxy resin. This is an additional step in the preparation of epoxy resin compositions, and introduces ester bonds into the composition, which has a negative effect on hydrolytic stability and water absorption of the composition in the cured state. The problem underlying the present invention is a flame-retardant epoxy resin without the above-mentioned drawbacks, which relates to an epoxy resin composition having a low halogen content or halogen-free and containing 3-hydroxyalkylphosphine oxide as flame retardant. Producing a composition. Accordingly, the present invention is particularly directed to a) at least one phosphorus-free epoxy resin compound, b) at least one polyglycidyl ether represented by the following general formula (I):

[0005]

[Chemical 2]

Wherein m is 2 or 3, n is 0 or 1, m + n is 3 and R ¹ has 1 to 6 carbon atoms, optionally branched alkyl, alicyclic or aromatic. Represents a group group, and R ² and R ³ are individually hydrogen or 1 to 4
Is a linear alkyl group having carbon atoms, R ⁴ is hydrogen, a linear alkyl group having 1 to 4 carbon atoms or an aromatic group, and R ⁵ is hydrogen or a methyl group. ),
And c) a curable flame-retardant epoxy resin composition containing a curing agent.

It has been found that the compositions according to the invention exhibit excellent flame retardancy at very low halogen contents and in the absence of any halogen. The composition according to the invention containing 0% halogen and 5% phosphorus, based on the total weight of the composition, gave a V = 0 rating according to the flame retardancy test UL94.
Further, in comparison with the above-mentioned prior art epoxy resin composition containing 3-hydroxyalkylphosphine oxide as a flame retardant, the composition of the present invention shows that the compound of the general formula (I) is well dissolved in a standard epoxy resin. Therefore, it is easy to mix, and in addition, in the cured state, it has a) a high glass transition point and b) an excellent retention of flame retardancy as expected during time.

The present invention also relates to the polyglycidyl ether represented by the above general formula (I). In the formula,
R ¹ is preferably an optionally branched alkyl group having ¹ to 6 carbon atoms, R ² , R ³ and R ⁴ are each preferably hydrogen or a methyl group, an ethyl group or a propyl group,
R ⁵ is preferably hydrogen. Particularly preferred polyglycidyl ethers of general formula (I) are those in which R ¹ is a methyl, ethyl, propyl, isopropyl, butyl or sec-butyl group,
² , R ³ , R ⁴ and R ⁵ are hydrogen. The most preferred polyglycidyl ethers of general formula (I) are triglycidyl ethers of tri (3-hydroxypropyl) phosphine oxide (TGE-FRT), and di (3
-Hydroxypropyl) 2-methylpropylphosphine oxide diglycidyl ether (DGE-FRD).

The epoxy resin composition of the present invention contains at least one polyglycidyl ether of the general formula (I), and thus can contain a mixture of at least two thereof. The polyglycidyl ether of general formula (I) is
It can be prepared by reacting the precursor 3-hydroxyalkylphosphine oxide compound with an appropriate amount of epihalohydrin, preferably epichlorohydrin, in the presence of a suitable base or acid catalyst known in the art.

The amount of polyglycidyl ether of general formula (I) in the composition of the invention is such that the proportion of phosphorus is 1 to 7% by weight, more preferably 3 to 7% by weight, based on the total weight of the composition. Preferably. Lower amounts of phosphorus do not give the desired level of flame retardancy, higher amounts are not economically advantageous. The selection of the phosphorus-free epoxy resin composition (hereinafter referred to as the epoxy resin compound) used in the composition of the present invention is not critical and depends on the field of application of the epoxy resin composition. In electrical and electronic end uses it is preferred to use one or more aromatic epoxy resin compounds, optionally mixed with one or more cycloaliphatic and / or aliphatic epoxy resin compounds. . Examples of suitable epoxy resin compounds are diglycidyl ether of diphenylol propane, diglycidyl ether of diphenylol methane or products obtained therefrom; diphenylol propane / formaldehyde resin, diphenylol methane / formaldehyde resin,
Polyglycidyl ethers of phenol / formaldehyde resins and cresol / formaldehyde resins; diglycidyl ethers of resorcinol; tetrakis (p-glycidylphenyl) ethane; phthalic acid, isophthalic acid,
Polyglycidyl esters of terephthalic acid and trimellitic acid; N, N-diglycidylaniline, N, N, O-triglycidyl-p-aminophenol, triglycidyl isocyanuric acid, N, N, N ', N'-tetra Glycidyl-bis- (p-aminophenyl) -methane; 1,4-
Di- and polyglycidyl compounds of polyhydric alcohols such as butanediol, trimethylolpropane and polyalkylene glycols, and halogenated epoxy resin compounds such as diglycidyl ether of tetrabromodiphenylolpropane and diphenylolpropane diene compounds. It is a reaction product of a liquid epoxy resin such as glycidyl ether and tetrabromodiphenylolpropane. When the epoxy resin composition of the present invention contains one or more halogenated epoxy resin compounds, the total halogen content of the composition is less than about 15% by weight, preferably about 10% by weight, based on the total weight of the composition. Less than, more preferably about 5
It is less than wt%. Preferred epoxy compounds are diphenylolpropane, diphenylolmethane and diglycidyl ethers of tetrabromodiphenylolpropane,
And a product obtained from said diglycidyl ether, or diphenylol propane / formaldehyde resin,
It is a polyglycidyl ether of diphenylol methane / formaldehyde resin, phenol / formaldehyde resin and cresol / formaldehyde resin.

The epoxy resin composition of the present invention contains at least one epoxy compound. Therefore,
The epoxy resin composition of the present invention preferably contains a mixture of at least two kinds of the above epoxy compounds, more preferably one or more kinds of the non-halogenated epoxy compounds and one or more kinds of the halogenated epoxy compounds. is there.

The type of curing agent used in the composition of the present invention is not critical and depends primarily on the type of epoxy resin used. The amount of curing agent used should be sufficient to obtain a complete cure. Suitable curing agents used in electrical and electronic epoxy resin compositions are, for example, amines, amides, and anhydrides.
Particularly suitable amine hardeners are, for example, diaminodiphenylmethane (DDM), isophoronediamine (IPD) and dicyandiamine (DICY). The amount of the curing agent used in the epoxy resin composition of the present invention is such that the ratio of amine hydrogen equivalent to epoxy equivalent is in the range of 0.9 to 1.5, preferably 0.9 to 1.1, and more preferably 1. The amount is such that 0.0.

The epoxy resin composition of the present invention may further include other additives commonly used in the art such as a curing accelerator and / or a filler and a colorant. Furthermore, the epoxy resin composition of the present invention can be produced by a method known in the art, for example, by blending or mixing the components in a desired order and technique. As mentioned above, the epoxy resin composition of the present invention is particularly suitable for use in electronics and electrical applications, but is also suitable for various other uses such as coatings, adhesives, flooring and the like. Accordingly, the present invention also relates to articles, in particular printed wiring boards, which contain the composition of the invention in the cured state.

[0014]

[Examples] Material : Epicoat 825 [(Shell Chemical Co., Ltd.) 57
Diglycidyl ether of diphenylolpropane (bisphenol A) having 12 mmol / kg EGC] Diglycidyl ether of tetrabromodiphenylolpropane (tetrabromobisphenol A) having 2690 mmol / kg EGC

Hardener : Isophoronediamine (IPD) Diaminodiphenylmethane (DDM)

Phosphorus-containing compound of the general formula (I) : 5871 mmol /
Di (3-hydroxypropyl) -2-with kg EGC
Diglycidyl ether of methylpropylphosphine oxide (DGE-FRD) Triglycidyl ether of tri (3-hydroxypropyl) phosphine oxide (TGE having an EGC of 7420 mmol / kg (T
GE-FRT)

Conventional phosphorus-containing compound : tri (3-hydroxypropyl) phosphine oxide (FRT) di (3-hydroxypropyl) -2-methylpropylphosphine oxide (FRD)

[Preparation Method of Phosphorus-Containing Compound of General Formula (I)] a) Preparation Method of DGE-FRD A round glass reactor having an appropriate size, a heating mantle, an anchor type rotary stirrer, a thermocouple, and a water separator. And 2 arranged in series
Equipped with 1 reflux condenser. A vacuum pump with an in-line dry ice strap was connected to the top of the condenser.
The applied vacuum was adjusted with a Buench 168 vacuum distillation controller. A Labotron LDP-26 metering drain pump was also directly connected to the reactor. Epichlorohydrin (ECH) 11 mol (1017.5 g), FRD 1.1 mol (244 g) and benzyltriethylammonium chloride (BETEC) 0.
03 mol (6.3 g) were mixed in a reactor and heated to 55 ° C. Sufficient vacuum was applied to bring the reaction mixture to reflux (typically 140-145 mbar). Maintaining these conditions, NaOH 4.4 as a 50% aqueous solution
Mole (176 g) was added dropwise in 3 equal portions over 3 hours.
During the addition of NaOH, the vacuum was adjusted so that the mixture of ECH and water was azeotropically distilled and the mixture was collected in a water trap. Water was separated and ECH was returned to the reactor. Post-reaction : After the addition of the aqueous NaOH solution was complete, the reaction mixture was stirred for a further 1.5 hours at 55 ° C. and 140-145 mbar. Workup : Water was added to the reaction mixture and the brine formed was separated. CH ₂ Cl ₂ was then added and the resulting solution was washed first with 10% aqueous Na ₂ HPO ₄ until neutral and then with water. The solvent and residual ECH were removed on a vacuum rotary evaporator at 120 ° C. and 20 mbar final conditions. Then 50 ml of water were added and stripped again on a rotary evaporator under the same final conditions. 357 g of a viscous liquid resin was obtained.

B) Method for preparing TGE-FRT As a starting material, 11 mol (1017.5 g) of ECH and FRT were used.
1.1 mol (248 g), BETEC 0.03 mol (6.3 g)
And DMSO 3.51 mol (275 g), and NaOH 6.6 mol (264 g) as a 50% aqueous solution,
The above method was repeated. As a result, viscous liquid resin 1
880 g were obtained. The characteristics of the product obtained by the above method are shown below.

Solids yield Weight average molecular weight Phosphorus weight% EGC mmol / g DGE-FRD 96% 334 9.3 5.92 TGE-FRT 64% 392 7.9 7.42

[Production of Cast Material] The compositions of the present invention and the comparative composition were prepared by mixing the respective components in proportions according to the compounding data shown in Tables 1 to 3. In each case, heating was required. The obtained uniform liquid material was poured into an aluminum tubular mold pretreated with a suitable mold release agent. The resin formulation was then heated at a temperature between 150 and 200 ° C. for a suitable time until fully cured.

[Measurement of physical properties of cast material] Underwriter Labor for samples cut from the cast material according to the test standard
UL-94 exam ("Standard for tests for atories")
flammability andof plastic material for parts in d
evices and appliances "4th edition June 18, 1991), measurements of burning time, dripping behavior and cotton ignition, and 94 V = 0, 94 V = 1 or 94 V = 2 of materials.
Was classified into Tan delta (E "/ E ') was measured by dynamic mechanical analysis.

[Results] The compounding data of the compositions A to H of the present invention and the comparative compositions 1 to 10 and the physical properties of the castings are shown in Tables 1-3.
Shown in the table. It should be noted that the relative amounts of each component in the formulation are due to the weight percentages of phosphorus and bromine required in the final casting. When comparing each composition,
Most importantly, the weight percentages of phosphorus and optionally bromine are the same.

Table 1 shows the inventive compositions A to D containing TGE-FRT. All compositions AD are UL-94
It can be seen that the grade is V = 0, and excellent results are shown in other tests. Note that it was not possible to prepare a comparative composition containing FRT instead of TGE-FRT. FRT is a solid substance that has been found to be very insoluble in epoxy resin compounds. Even if heated, a uniform FRT epoxy resin solution could not be obtained.

Table 2 shows the compositions EH of the present invention and the comparative compositions 1-4. Compositions E and 1, F and 2, G
It can be concluded that the use of DGE-FRD gives higher tan delta values than the injection moldings containing FRT giving the same weight percent phosphorus by comparing 3 and 3 and H and 4. Further, all of Compositions AD were UL-94.
It can be seen that it gives a rating of V = 0 and gives excellent results for the other tests.

Table 3 shows comparative compositions 5-10. From this table it can be seen that only compositions 9 and 10 containing 20% by weight of bromine give a UL-94 V = 0 rating.

[0027]

[Table 1]

[0028]

[Table 2]

[0029]

[Table 3]

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Internal reference number FI Technical indication location H05K 1/03 610 L 7011-4E (72) Inventor Anthony Weiburg The Netherlands, 1031 · Sem · Amsteldam, Bathaysweg 3 (72) Inventor Ian Peter Vrienhoek, Netherlands, 1031 Säem Amsteldam, Bathaysweg 3

Claims (17)

[Claims] 1. A polyglycidyl ether represented by the following general formula (I). [Chemical 1] (In the formula, m is 2 or 3, n is 0 or 1, and m + n is 3
And R ¹ represents an optionally branched alkyl group, alicyclic group or aromatic group having ¹ to 6 carbon atoms,
R ² and R ³ each independently represent hydrogen or a linear alkyl group having 1 to 4 carbon atoms, R ⁴ represents hydrogen, a linear alkyl group having 1 to 4 carbon atoms, or an aromatic group;
⁵ represents hydrogen or a methyl group. ) 2. R ¹ is an optionally branched alkyl group having ¹ to 6 carbon atoms, R ² , R ³ and R ⁴
Is a hydrogen, a methyl group, an ethyl group or a propyl group, and R ⁵ is a hydrogen atom. 3. R ¹ is an optionally branched methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group or a tert-butyl group, and each of R ² , R ³ , R ⁴ and R ⁵ is hydrogen. The polyglycidyl ether according to claim 2. 4. A triglycidyl ether of tri (3-hydroxypropyl) phosphine oxide. 5. A diglycidyl ether of di (3-hydroxypropyl) 2-methylpropylphosphine oxide. 6. A curable flame retardant composition comprising a) at least one phosphorus-free epoxy resin compound, b) at least one polyglycidyl ether according to claims 1-5, and c) a curing agent. Epoxy resin composition. 7. The proportion of phosphorus is 1 to 7 per the total amount of the composition.
The composition of claim 6 which is in weight percent. 8. The epoxy resin compound is a diglycidyl ether of diphenylolpropane, diphenylolmethane or tetrabromodiphenylolpropane, or a product obtained from one of the diglycidyl ethers; Alternatively, the composition according to claim 6 or 7, which is a polyglycidyl ether of diphenylol propane / formaldehyde resin, diphenylol methane / formaldehyde resin, phenol / formaldehyde resin or cresol / formaldehyde resin. 9. The composition according to claim 6, which contains a mixture of a non-halogenated epoxy compound and a halogenated epoxy compound. 10. A halogen content of 15 per total composition.
The composition according to any one of claims 6 to 9, which is less than wt%. 11. The composition according to claim 6, wherein the curing agent is an amine, a carboxylic acid anhydride or an amide. 12. The composition according to claim 11, wherein the amine curing agent is diaminodiphenylmethane, isophoronediamine or dicyandiamide. 13. A reaction of a precursor 3-hydroxyalkylphosphine oxide compound with a suitable amount of epihalohydrin in the presence of a suitable base or acid catalyst.
A method for producing the polyglycidyl ether according to claim 1. 14. A method for producing a composition according to any one of claims 6 to 12 by blending or mixing the reactants in a desired order or method. 15. A method of using the composition according to any one of claims 6 to 12 for producing a printed wiring board. 16. An article containing the composition according to claim 6 in a cured state. 17. A printed wiring board containing the composition according to claim 6 in a cured state.