JPH09249800A - Flame retardant resin composition - Google Patents

Abstract

(57) 【Abstract】 PROBLEM TO BE SOLVED: To obtain a molded product having a high degree of flame retardancy, good appearance and mechanical properties, and having good processability in resin kneading and injection molding. To provide a polyester resin composition. A flame-retardant resin composition comprising a polyester resin, a phosphoric acid ester represented by the formula (I), and a novolac-type phenol resin. (In the formula, X represents a bond or —C (CH ₃ ) ₂ —, and n represents 0 or 1.)

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a novel flame-retardant resin composition. More specifically, a non-halogen flame-retardant polyester resin composition having good processability for resin kneading and injection molding, having a high degree of flame retardancy, and obtaining a molded article having good appearance and mechanical properties. Regarding

[0002]

2. Description of the Related Art Polyester resins such as polybutylene terephthalate have excellent mechanical properties, heat resistance, chemical resistance, etc., and are therefore widely used as molded articles for applications in the electric / electronic fields, automobile fields, etc. ing.

[0003] Among these, there are many uses requiring flame retardancy, and mainly halogen compounds and antimony compounds are used as flame retardants,
A resin provided with flame retardancy by using it as a flame retardant aid is provided.

However, halogen-based flame retardants may cause corrosion products to corrode metals that are electric parts, and some halogen-based flame retardants have a problem of environmental impact. A flame-retardant resin of the type is required.

As a non-halogen flame retardant, there are phosphorus compounds, and low molecular weight phosphoric acid esters such as triphenyl phosphate have been often used. By the way, a polyester resin such as polybutylene terephthalate has a relatively high processing temperature, and in the case of a low molecular weight phosphoric acid ester, there are problems of bleed-out and heat resistance. Therefore, JP-A-5-1079 discloses a heat-resistant phosphoric acid ester having a high molecular weight.

However, as a result of studies by the present inventors, when these heat-resistant phosphoric acid esters are used in polyester resin, the problems of bleed-out and heat resistance are improved, but in order to obtain high flame retardancy. It is necessary to add a relatively large amount of a combination agent such as a phosphoric acid ester and a melamine compound. For this reason, the workability of resin kneading and the workability of injection molding have become problems, and the physical properties such as mechanical properties of molded products have not been satisfactory. Further, particularly when glass fibers are blended, a relatively small amount of glass fibers up to about 20 parts by weight per 100 parts by weight of polyester resin is blended with a relatively large amount of phosphoric acid ester and a concomitant melamine compound. However, it was difficult to obtain sufficient flame retardancy.

[0007]

The object of the present invention is to obtain a molded product having a high degree of flame retardancy, good appearance and mechanical properties, and having good workability in resin kneading and injection molding. A flame-retardant polyester resin composition of the present invention is provided. Further, when glass fiber is compounded, the flame retardant resin composition is to be prepared in a wide range from a relatively small amount to a large amount.

[0008]

Means for Solving the Problems As a result of intensive studies for solving the above problems, the present inventors have found that a specific phosphoric acid ester is
It was found that by using an appropriate amount of a specific compound that works as a concomitant agent, it is possible to make it highly flame-retardant, have good mechanical properties, and have no problems with resin kneading and injection molding processability. The invention was reached.

That is, according to the present invention, (A) 100 parts by weight of the polyester resin, (B) 5 to 60 parts by weight of the phosphoric ester represented by the formula (I), and (C) the novolac type phenolic resin 3 to 40. A flame-retardant resin composition comprising 1 part by weight and (D) 0 to 50 parts by weight of glass fiber is provided.

[0010]

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(In the formula, X is a bond or --C (CH ₃ ) ₂
-, And n represents 0 or 1. Examples of the polyester resin (A) used in the present invention include polybutylene terephthalate, polyester elastomers composed of polybutylene terephthalate and polyoxytetramethylene glycol, polybutylene naphthane dicarboxylate, and polycyclohexane dimethanol terephthalate. Further, a copolymerized polymer obtained by copolymerizing a small amount of a copolymerization component with these polymers may be used.

Among these, polybutylene terephthalate,
Copolymer with a small amount of isophthalic acid, naphthalene dicarboxylic acid, etc., polyester elastomer consisting of polybutylene terephthalate and polyoxytetramethylene glycol, and copolymer with a small amount of isophthalic acid, naphthalene dicarboxylic acid etc. Polymers are particularly preferred.

Phosphate ester (B) used in the present invention
Is a compound represented by formula (I).

[0014]

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(In the formula, X is a bond or —C (CH ₃ ) ₂ —
And n represents 0 or 1. Examples of the phosphoric acid ester (B) include compounds represented by formula (II), formula (III) or formula (IV).

[0016]

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The amount of the phosphoric acid ester added is 5 to 50 parts by weight, preferably 5 to 40 parts by weight, based on 100 parts by weight of the polyester resin (A). If the amount added is less than 5 parts by weight, the flame retardance is not sufficient, and if it is more than 50 parts by weight, the mechanical properties of the molded product will deteriorate, which is not preferable.

The novolac type phenolic resin (C) used in the present invention is a thermoplastic phenolic resin, to which no curing agent such as hexamethylenetetramine is added. A pure phenol resin obtained from phenol or formaldehyde or a modified phenol resin is used.

The amount of novolac type phenolic resin added is
3-40 relative to 100 parts by weight of polyester resin (A)
Parts by weight, preferably 5 to 30 parts by weight. Addition amount is 3
If it is less than part by weight, the flame retardance is not sufficient, and if it is more than 40 parts by weight, the mechanical properties of the molded product will be poor, which is not preferable.

The glass fiber (D) used in the present invention is
Although not particularly limited, alkali-free glass fiber is preferably used.

The amount of glass fiber added is 0 to 50 parts by weight, preferably 0 to 40 parts by weight, based on 100 parts by weight of the polyester resin (A).

Melamine compound (E) used in the present invention
Is melamine or a salt thereof, and examples thereof include melamine, melamine cyanurate, and melamine isocyanurate.

The tetrazole compound used in the present invention is 5,5'-bistetrazole 2-ammonium,
5,5′-bistetrazole 2-aminoguanidine,
An example is 5,5′-bistetrazolepiperazine.

The addition amount of the melamine compound or the tetrazole compound is 5 with respect to 100 parts by weight of the polyester resin.
-100 parts by weight, preferably 5-50 parts by weight. If the amount added is less than 5 parts by weight, the effect on flame retardancy due to the addition of these compounds is not sufficient, and if the amount added is 100 parts by weight or more, the mechanical properties of the molded product will be unfavorable.

The fluororesin (F) used in the present invention is polytetrafluoroethylene, tetrafluoroethylene /
An ethylene copolymer etc. are illustrated.

Fluorine resin is added in the amount of polyester resin 1
It is 0.01 to 2 parts by weight based on 00 parts by weight. If the addition amount is less than 0.01 parts by weight, the effect of flame retardancy due to the addition of the fluorine resin is not sufficient, and if it is more than 2 parts by weight, it is not preferable in terms of moldability.

The flame-retardant resin composition of the present invention is a reinforcing filler other than glass fiber, as long as the object of the present invention is not impaired.
Antioxidants, heat stabilizers, impact modifiers such as various elastomers, nucleating agents, plasticizers, release agents, pigments such as titanium oxide and carbon black, and commonly used additives such as dyes may be further added. good.

The flame-retardant resin composition of the present invention is produced by a usual method. For example, a method of melt-kneading a polyester resin, a phosphoric acid ester, a novolac type phenol resin, and a glass fiber using an extruder can be used.

The flame-retardant resin composition of the present invention can be molded by ordinary injection molding, extrusion molding or the like.

[0030]

EFFECTS OF THE INVENTION The flame-retardant resin composition of the present invention is a non-halogen flame-retardant resin composition having a high degree of flame-retardant property and good appearance and mechanical properties of molded articles. In addition, since the resin kneading processability and injection molding processability are good, its industrial value is extremely large.

[0031]

The present invention will be described in more detail with reference to the following examples. In the examples, “parts” means “parts by weight”. Intrinsic viscosity was measured at 35 ° C. using an orthochlorophenol solvent.

[Example 1] 57 parts of polybutylene terephthalate having an intrinsic viscosity of 0.90, 20 parts of a phosphoric ester represented by the formula (II), 8 parts of a novolac type phenol resin (PR-53195 of Sumitomo Dures Co., Ltd.), and 250 parts of glass fiber using an extruder (Laboplast mill)
Was kneaded, the thread was extruded, and chips were formed by a cutter. Extrudability was stable with almost no thread breakage.

The chips thus obtained were dried at 120 ° C. for 4 hours, and then combustion test pieces and tensile test pieces were injection molded under the conditions of a melting temperature of 250 ° C. and a mold temperature of 80 ° C.

[0034]

[Table 1]

Using this test piece, a vertical combustion test (UL9
4, 1/16 inch) and tensile test (ASTM D-6
38) was carried out. The results are as shown in Table 1.

The result of the combustion test showed high flame retardancy corresponding to UL94 V-0.

[0037]

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Comparative Example 1 60 parts of polybutylene terephthalate having an intrinsic viscosity of 0.98, 20 parts of the phosphoric acid ester represented by the formula (II), 15 parts of melamine cyanurate, and 15 parts of glass fiber were prepared in the same manner as in Example 1. It was extruded into chips. The extrudability was unstable as compared with Example 1 due to frequent thread breakage.

Further, in the same manner as in Example 1, molding, combustion test and tensile test were carried out. The results are shown in Table 1.

The result of the combustion test was equivalent to UL94 V-2, which was inferior to that of Example 1. The tensile properties were also inferior to those of Example 1.

[Examples 2 to 6 and Comparative Example 2] The procedure of Example 1 was repeated, except that the amount of polybutylene terephthalate, the type of compounding agent, and the amount were as shown in Table 1. Table 1 shows the results
It was shown to.

[Example 7] Polybutylene terephthalate (30% by weight) and polyoxytetramethylene glycol having an average molecular weight of 2000 (70% by weight) were used, and the melting point was 190.
Polyester elastomer 73 with ℃ and intrinsic viscosity 1.30
Parts, 15 parts of the phosphoric acid ester represented by the formula (II), and 12 parts of the novolac type phenolic resin (PR-53195) are kneaded at 230 ° C. using an extruder (Laboplast mill) to form chips in the same manner as in Example 1. did.

The chips thus obtained were dried at 120 ° C. for 4 hours, and then a combustion test piece was injection molded under the conditions of a melting temperature of 230 ° C. and a mold temperature of 80 ° C.

Using this test piece, a vertical combustion test (UL9
In accordance with No. 4, a sample piece thickness of 1/16 inch) was carried out. The results are as shown in Table 1.

The results of the combustion test showed excellent flame retardancy equivalent to UL94 V-0.

Comparative Example 3 The procedure of Example 5 was repeated except that the amount of polyester elastomer, the type of compounding agent and the amount were as shown in Table 1. The results are shown in Table 1.

The result of the combustion test was UL94 V-2 equivalent, which was inferior to that of Example 5.

Claims (4)

[Claims] (A) 100 parts by weight of a polyester resin,
(B) 5 to 50 phosphoric acid ester represented by the general formula (I)
A flame-retardant resin composition comprising 3 parts by weight, (C) 3 to 40 parts by weight of novolac type phenolic resin, and (D) 0 to 50 parts by weight. Embedded image (In the formula, X is a bond or —C (CH ₃ ) ₂ —, and n is 0.
Or 1 is shown. ) 2. The flame-retardant resin composition according to claim 1, wherein the polyester resin (A) is polybutylene terephthalate or a polyester elastomer composed of polybutylene terephthalate and polyoxytetramethylene glycol. 3. The flame-retardant resin composition according to claim 1, which further comprises 5 to 100 parts by weight of the melamine compound or the tetrazole compound (E) with respect to 100 parts by weight of the polyester resin (A). 4. The flame-retardant resin composition according to claim 1, 2 or 3, further comprising 0.01 to 2 parts by weight of (F) a fluororesin per 100 parts by weight of the polyester resin (A). .