JPH1180178A - Oligomer terminated with phosphorus-containing phenol and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject new phosphorus-containing phenol-terminated oligomer relatively high in the content of phosphorus, good in workability, and useful as a curing agent for epoxy resins, a phosphorus reaction type flame retardant for various resin raw materials and the like. SOLUTION: This new phosphorus-containing phenol-terminated oligomer of the formula [R<1> is a 6-14C aryl; Ar is a divalent aromatic residue obtained by substituting the two hydrogen atoms of the aromatic ring of (substituted) benzene, (substituted) biphenyl, diphenylmethane, diphenyl-2,2'-propane or cumylbenzene; (n) is 0, 1-50]. The oligomer of the formula is useful as a curing agent for epoxy resins, a phosphorus flame retardant used in raw materials for various kinds of resins such as epoxy resins and polyester resins, and the like. The phosphorus-containing phenol-terminated oligomer of the formula is obtained by reacting an arylphosphonic acid dihalide with an aromatic dihydroxy compound in the presence or absence of an acid acceptor.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a phosphorus-containing phenol-terminated oligomer having excellent flame retardancy, which is used as a curing agent for epoxy resins and as a raw material for various resins such as epoxy resins and polyester resins, and a method for producing the same.

[0002]

2. Description of the Related Art Originally, most of epoxy resins were used as adhesives by making use of the properties of cured products. Subsequently, new uses such as paints and glass fiber reinforced plastics increased due to the excellent mechanical strength and electrical insulation properties of the cured product, and recently, applications as electric and electronic materials, such as laminates, molding materials, Applications such as sealing materials have become noticeable. In the wake of a series of fires and fire accidents in home appliances, the demand for flame-retardant insulating materials has increased, and the use of flame-retardant epoxy resins has started in insulating materials, vehicles, ships, aircraft, and building materials. It is also used for flame retardation of housings and the like.

Conventionally, as a method of making an epoxy resin flame-retardant, for example, "Plastic Swage" (publisher: Plastic Swage Co., Ltd.), June 14, 1991, No. 14
As described on pages 6 to 153, a method using a halogen-containing epoxy compound such as diglycidyl ether of tetrabromobisphenolΑ, polyglycidyl ether of brominated phenol novolak, or a halogen-containing organic compound such as decabromobiphenyl ether. It has been known. However, these flame retardants reduce heat resistance, electrical insulation, and the like, and may generate toxic gas during fire combustion. In addition, since a communication network was paralyzed by a fire at a nuclear power plant or a telephone office, it has been desired to reduce hydrogen halide and reduce smoke.

On the other hand, as phosphorus-based flame retardants,
Inorganic compounds such as polyphosphates and red phosphorus, and organic compounds mainly containing phosphate esters, particularly triphenyl phosphate (TPP), are widely used. However, these phosphorus-based flame retardants have the moisture resistance of epoxy resin,
There was a problem that heat resistance and the like were reduced.

[0005] Phosphorus-containing epoxy compounds have been studied as phosphorus-based reactive flame retardants, and aromatic compounds having a phosphorus atom incorporated in the skeletal chain (JP-A-61-134395, JP-A-2-272014). And aliphatic ether compounds (JP-A-62-223215), aromatic compounds having a phosphorus atom in the side chain (JP-A-5-39345, JP-A-61-148219) and the like are known. . However, compounds in which an aromatic ring is not directly bonded to a phosphorus atom (JP-A-62-223215, JP-A-61-223215)
No. 148219) is an aromatic compound having low heat resistance and two or more aromatic rings bonded to a phosphorus atom like triphenylphosphine oxides (JP-A-61-134395, JP-A-5-39345). Is expensive and the purification of synthetic products is not easy. Aromatic compound having only one aromatic ring bonded to a phosphorus atom (JP-A-2-272014)
Is a low-viscosity liquid. For example, when it is used as a casting resin, its viscosity cannot be adjusted, or when it is used as a laminate material, there is a problem in workability because the prepreg has stickiness. Further, the aromatic compound disclosed in JP-A-5-39345 has a problem that the phosphorus content is low.

[0006]

An object of the present invention is to provide a phosphorus-containing phenol-terminated oligomer having a relatively high phosphorus content and good workability.

Another object of the present invention is to provide a suitable method for producing the above-mentioned phosphorus-containing phenol-terminated oligomer.

[0008]

That is, the present invention provides a compound represented by the general formula (I):

[0009]

Embedded image (Wherein, R ¹ represents an aryl group having 6 to 14 carbon atoms;
r is benzene, biphenyl, an alkyl-substituted benzene substituted with an alkyl group having 1 to 6 carbon atoms, an alkyl-substituted biphenyl substituted with an alkyl group having 1 to 6 carbon atoms, diphenylmethane, diphenyl-2,2'-propane or cumylbenzene Represents a divalent aromatic residue in which two hydrogens of the aromatic ring have been substituted, n is 0.1 to 50, and the resulting oligomer is a mixture. The present invention provides a phosphorus-containing phenol-terminated oligomer represented by the following formula:

[0010] The present invention also relates to the above-mentioned phosphorus-containing phenol-terminated oligomer, which comprises reacting (A) an arylphosphonic dihalide and (B) an aromatic dihydroxy compound in the presence or absence of an acid acceptor. It provides a manufacturing method.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The phosphorus-containing phenol-terminated oligomer of the present invention is represented by the above general formula (I), and the aryl group represented by R ¹ in the general formula (I) includes:
It has 6 to 14 carbon atoms, and examples thereof include a phenyl group and a naphthyl group. Among them, a phenyl group is preferred. The aromatic nucleus such as phenyl group and naphthyl group may have a substituent such as alkyl group, hydroxyl group and amino group.

In the general formula (I), n is from 0.1 to 50, and the resulting oligomer is a mixture containing a monomer. When the value of n exceeds 50, the cured product characteristics of the resin obtained by using the oligomer of the present invention are deteriorated. n is 0.1 to
10 is preferable, and 0.1 to 5 is more preferable.

The phosphorus-containing phenol-terminated oligomer of the present invention preferably has a phosphorus content of 6 to 12% by weight from the viewpoint of flame retardancy. In addition, the hydroxyl equivalent is 100 to 519 g.
/ Eq, weight average molecular weight by GPC is from 250 to 140
0, the number average molecular weight is preferably 110 to 600.

The phosphorus-containing phenol-terminated oligomer of the present invention comprises (A) an arylphosphonic dihalide and (B)
It can be obtained by reacting an aromatic dihydroxy compound in the presence or absence of an acid acceptor.

The (A) arylphosphonic dihalides include unsubstituted arylphosphonic dichlorides such as phenylsulfonic dichloride, phenylsulfonic dibromide, and naphthylphosphonic dichloride, alkyl-substituted phenylphosphonic dichlorides, hydroxyphenylphosphonic dichlorides, and the like. Substituted arylphosphonic dihalides such as aminophenylphosphonic dichloride, alkyl-substituted phenylphosphonic dichloride, hydroxynaphthylphosphonic dichloride, aminonaphthylphosphonic dichloride and the like are used, among which phenylphosphonic dichloride is preferable. Examples of the aromatic dihydroxy compound include hydroquinone, resorcinol, 4,4'-dihydroxybiphenyl, and 3,4'-dihydroxybiphenyl. , Unsubstituted aromatic dihydroxy compound such as 3,3'-dihydroxybiphenyl, 3,3 '
-Dimethyl-4,4'-dihydroxybiphenyl, 3,
3 ', 5,5'-tetramethyl-4,4'-dihydroxybiphenyl, 4,4'-dihydroxydiphenylmethane, 3,4'-dihydroxydiphenylmethane, 3,
Such as 3'-dihydroxydiphenylmethane, 4,4'-dihydroxydiphenyl-2,2'-propane, 1,3-bis (4-hydroxycumyl) benzene, and 1,4-bis (4-hydroxycumyl) benzene; Unsubstituted aromatic dihydroxy compounds are used, among which hydroquinone, resorcinol, 4,4'-dihydroxybiphenyl, 4,4'-dihydroxydiphenyl-2,
2'-propane, 3,3 ', 5,5'-tetramethyl-
4,4'-dihydroxybiphenyl is preferred, and hydroquinone and resorcinol are particularly preferred.

Examples of the acid acceptor include alkalis such as sodium hydroxide, potassium hydroxide and calcium hydroxide, and amines such as dimethylaminopyridine, pyridine and triethylamine. Among them, dimethylaminopyridine, pyridine , Triethylamine and the like are preferred, and triethylamine is more preferred.

As the solvent, an inert solvent such as ethers such as tetrahydrofuran, ketones such as methyl ethyl ketone, and esters such as ethyl acetate is preferably used, and the concentration is preferably 50% by weight or less.

The amount of each component in the present invention is as follows:
Component (B) 70 to 3 with respect to 100 parts by weight of component (A)
00 parts by weight, and the component (B) 70 to 2
More preferably, the content of component (B) 70
It is particularly preferred that the amount be from 170 to 170 parts by weight. When the amount of the component (B) is less than 70 parts by weight, the number of hydroxyl groups tends to be extremely small due to a side reaction.
When used in a laminated material, the flame retardancy tends to decrease.

The reaction temperature in the present invention is from -70 to 50.
° C, more preferably -70 to 30 ° C, and particularly preferably -70 to 0 ° C. If the reaction temperature is lower than -70 ° C, the reaction rate tends to decrease remarkably, and if it exceeds 50 ° C, a side reaction tends to occur easily.

The reaction time in the present invention is 0.1 to 24.
The time is preferably set to 0.5 to 12 hours, more preferably 2 to 5 hours. If the reaction time is less than 0.1 hour, the reaction tends to be insufficient, and if it exceeds 24 hours, side reactions such as hydrolysis tend to occur easily.

The pressure of the reaction system in the present invention is not particularly limited. Therefore, the reaction can usually be carried out at normal pressure.

[0022]

The present invention will be described below with reference to examples. However, the present invention is not limited to the following examples.

Example 1 85 parts by weight of resorcinol (manufactured by Wako Pure Chemical Industries, Ltd.) and triethylamine (manufactured by Wako Pure Chemical Industries, Ltd.) 104 were placed in a reaction vessel equipped with a stirrer, thermometer, and dropping funnel in a draft. Parts by weight and tetrahydrofuran (manufactured by Wako Pure Chemical Industries, Ltd.) 53
4 parts by weight were sequentially added, and while keeping the inside of the reaction vessel at 0 to 5 ° C., a solution of 100 parts by weight of phenylphosphonic dichloride (manufactured by Wako Pure Chemical Industries, Ltd.) in 89 parts by weight of tetrahydrofuran was stirred over 90 minutes. It was dropped. After the completion of the dropwise addition, the cooling was stopped, and the stirring was further continued for 2 hours. After completion of the reaction, the mixture was filtered to remove triethylamine hydrochloride, and further washed with distilled water to remove residual triethylamine hydrochloride and unreacted resorcinol. Then room temperature, vacuum 13P
Under the condition of a, tetrahydrofuran was distilled off to obtain a pale brown solid. The yield was 87%, and it was confirmed by IR and NMR that the structure was represented by the general formula (I). The phosphorus content of this phenol-terminated oligomer is 1
0.8% by weight, weight average molecular weight by GPC is 1,16
4. The number average molecular weight was 582. Further, n in the general formula (I) was 1.70.

Example 2 A phosphorus-containing phenol-terminated oligomer was obtained in the same manner as in Example 1 except that the amount of resorcinol was changed to 113 parts by weight. The phosphorus content of this phenol-terminated oligomer was 9.1% by weight, the weight average molecular weight by GPC was 758, and the number average molecular weight was 386. Also,
N in the general formula (I) was 1.13.

Example 3 100 parts by weight of the phosphorus-containing phenol-terminated oligomer of Example 1, 70 parts by weight of novolak type epoxy, 5.1 parts by weight of triphenylphosphine as a catalyst, and 100 ° C.
After heating and melting at a pressure of 2 MPa,
Pressing at 1.5 ° C. for 1.5 hours results in a phosphorus content of 6.
A 2% by weight resin plate was prepared and subjected to a combustion test based on the UL94V method. As a result, the total combustion time is 17 seconds,
The maximum burning time was 6 seconds, indicating a flammability of V-0.
In addition, after the above resin composition was made into a methyl ethyl ketone solution and impregnated in a glass cloth, the resin composition was heated at 120 ° C. for 5 minutes.
The solvent was removed using a vertical hot-air dryer to prepare a prepreg. The obtained prepreg had no stickiness and had good workability such as handleability. Further, n in the general formula (I) was 1.70.

Comparative Example 1 Example 3 was repeated except that the resin of Example 3 was changed to 100 parts by weight of novolak epoxy and 53 parts by weight of phenol novolak.
A resin plate was prepared in the same manner as described above, and a combustion test was performed. As a result, the resin plate was completely burned.

Reference Example A phosphorus-containing phenol-terminated oligomer was obtained in the same manner as in Example 1 except that the amount of resorcinol was changed to 311 parts by weight. The phosphorus content of this phenol-terminated oligomer was 4.3% by weight, the weight average molecular weight by GPC was 385, and the number average molecular weight was 186. Next, the procedure of Example 3 was repeated except that the phosphorus-containing phenol-terminated oligomer was changed to 100 parts by weight and novolak epoxy was changed to 247 parts by weight.
A resin plate was prepared in the same manner as described above, and a combustion test was performed. As a result, the resin plate was completely burned. Further, n in the general formula (I) was 0.54.

[0028]

The phosphorus-containing phenol-terminated oligomer of the present invention is excellent in that it has a high phosphorus content and good workability. By changing the molecular weight of the oligomer, the viscosity can be adjusted in the case of a liquid, and the melt viscosity can be adjusted in the case of a semi-solid or solid. When it is used for a casting resin, it is necessary to adjust its viscosity. By using the phosphorus-containing phenol-terminated oligomer of the present invention, it is possible to adjust the viscosity to an appropriate value and improve the casting workability. Further, when used as a laminate material, the molecular weight can be increased so as to be semi-solid or solid, the prepreg can be made non-sticky, and workability can be improved. Due to these effects, the phosphorus-containing phenol-terminated oligomer of the present invention is suitable for flame-retarding cast products, laminates, molded products, sealing materials, fibers, vehicles, ships, aircraft, building materials, housings, and the like.

According to the method for producing a phosphorus-containing phenol-terminated oligomer of the present invention, the above-mentioned phosphorus-containing phenol-terminated oligomer can be produced with high yield.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C08G 59/62 C08G 59/62

Claims (4)

[Claims] 1. A compound of the general formula (I) (Wherein, R ¹ represents an aryl group having 6 to 14 carbon atoms;
r is benzene, biphenyl, an alkyl-substituted benzene substituted with an alkyl group having 1 to 6 carbon atoms, an alkyl-substituted biphenyl substituted with an alkyl group having 1 to 6 carbon atoms, diphenylmethane, diphenyl-2,2'-propane or cumylbenzene Represents a divalent aromatic residue in which two hydrogens of the aromatic ring have been substituted, n is 0.1 to 50, and the resulting oligomer is a mixture. A) a phenol-terminated oligomer containing phosphorus. 2. R ¹ is a phenyl group and Ar is 1,3
The phosphorus-containing phenol-terminated oligomer according to claim 1, which is a phenylene group. 3. The phosphorus-containing phenol-terminated oligomer according to claim 1, wherein the phosphorus content is 6 to 12% by weight. 4. The phosphorus-containing phenol-terminated oligomer according to claim 1, wherein (A) the arylphosphonic dihalide and (B) the aromatic dihydroxy compound are reacted in the presence or absence of an acid acceptor. Manufacturing method.