JPH0830141B2 - Flame retardant resin composition - Google Patents

Description

TECHNICAL FIELD The present invention relates to a flame-retardant resin composition having excellent mechanical properties and thermal stability.

[Prior Art] A thermoplastic polyester flame-retardant resin composition using a flame retardant containing an organic halogen compound as a main component, particularly a polyethylene terephthalate flame-retardant resin composition, has a relatively high molding temperature, There is a problem with thermal stability because the heat deterioration is remarkable.

As a thermoplastic polyester flame-retardant resin composition having improved thermal stability, for example, a composition containing a specific compound having excellent thermal stability described in JP-A-57-2357 is known. . In this publication, a specific substance containing a compound that lowers T _PK by at least 4 ° C. and an antimonate of a metal of Group I, II or VIII of the periodic table are allowed to coexist in a flame retardant system. In the meantime, it is described that the flame retardancy is enhanced without adversely affecting the thermal stability of the resin composition.

However, when the above-mentioned specific substance and antimonate are used, there is a problem that the mechanical strength of the resin composition is lowered.

[Problems to be Solved by the Invention] The present invention has been made in view of the above prior art, and provides a flame-retardant resin composition having relatively large mechanical strength and excellent thermal stability. The purpose is.

[Means for Solving Problems] The present invention provides a composition comprising a polyethylene terephthalate resin, an alkali metal salt of an ethylene / α, β-unsaturated carboxylic acid copolymer, and a flame retardant containing an organic halogen compound. And 2,2 '-(1,3-phenylene) -bis (2-
Oxazoline) or 2,2 '-(1,4-phenylene) -bis- (2-oxazoline) in an amount of 0.05 to 5.0% by weight.

[Operations and Examples] As the polyethylene terephthalate resin used in the present invention, terephthalic acid or a derivative thereof having an ester forming ability is used as an acid component, and a glycol having 2 to 10 carbon atoms or an ester forming ability thereof is used as a glycol component. It refers to a linear saturated polyethylene terephthalate resin obtained by using the derivative. Specifically, polyethylene terephthalate, polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate,
Examples thereof include polytetramethylene terephthalate and polyhexamethylene terephthalate, which may be used alone or in combination of two or more. Of these, polyethylene terephthalate is particularly preferable because it has excellent heat resistance and mechanical strength. Further, the polyethylene terephthalate-based resin may contain other components such as diethylene glycol, polyalkylene oxide, aromatic diols, etc. within a range of up to 50% by weight. In particular, when 0.5 to 40% by weight of a modified polymer containing a weight polymer of alkylene oxide having 1 to 4 carbon atoms or a phenylene unit is contained in the obtained flame retardant resin composition, the obtained resin composition is It has excellent crystallinity.
Especially the general formula (II): (In the formula, X ₉ is a —C (CH ₃ ) ₂ — group, —SO ₂ — group, —CO— group or —O— group, R ₂ is an alkylene group having 2 or 3 carbon atoms,
n and m each represent an integer of 5 to 15) A mixture of 0.5 to 20 parts (parts by weight, the same applies hereinafter) of diol represented by 80 to 99.5 parts of polyethylene terephthalate, or a block copolymer thereof is used in view of heat resistance. Is preferred.

A mixture of 0.5 to 20 parts of a diol represented by the general formula (II) and 80 to 99.5 parts of polyethylene terephthalate or a block copolymer thereof is further melt-mixed with a polyethylene terephthalate resin and used after dilution by a letdown method. It is preferable that the concentration of the diol represented by the general formula (II) is 0.5 to 20% by weight.

The intrinsic viscosity of the polyethylene terephthalate resin is 1: 1 with phenol and 1,1,2,2, -tetrachloroethane.
When measured at 25 ° C in a mixed solvent mixed in a weight ratio of
It is preferably 0.4 to 1.2. Further, it is preferably 0.5 to 1.0, particularly 0.55 to 0.70.

The flame retardant referred to in the present invention means a compound containing an organic halogen compound as a main component and an antimony compound as the case requires. Specific examples of the organic halogen compound include tetrabromobisphenol A and its oligomer, decabromobiphenyl oxide, octabromobiphenyl oxide, poly-dibromophenylene oxide, brominated polystyrine, 2 moles of tetrachlorocyclopentadiene and 1 mole of cyclooctadiene. Condensation product with, poly pentabromobenzyl acrylate, tetrabisphenol A
And cyanuric chloride and tribromophenol condensate, hexabromocyclodecane, tribromophenol and glycidol condensate. Among the above compounds, a halogen-containing aromatic compound in which a halogen atom is directly bonded to an aromatic ring is preferable because the flame retardant has good thermal stability. The halogen is preferably bromine or chlorine.

The amount of the organic halogen compound as the flame retardant may be an amount sufficient to make the flame-retardant resin composition flame-retardant, and is usually 5 to 5 parts with respect to 100 parts of the polyethylene terephthalate resin.
It is 0 part, preferably 10 to 30 parts. When the content of the organic halogen compound is less than 5 parts, the required flame retardancy cannot be obtained, and when it exceeds 50 parts, the mechanical strength is significantly deteriorated.

In the present invention, examples of the antimony compound used as necessary include antimony trioxide, antimony pentoxide, sodium antimonate, potassium antimonate, zinc antimonate, etc., but the thermal stability of the flame-retardant resin composition Sodium antimonate is superior in sex. Particularly, sodium antimonate calcined at a temperature of 600 ° C. or higher is preferable, and the most preferable is sodium antimonate having an average particle diameter of 2 to 10 μm calcined at 600 ° C. or higher. The amount of the antimony compound used is 0 to 20 parts, preferably 1 to 15 parts, particularly preferably 2 to 10 parts, relative to 100 parts of the polyethylene terephthalate resin.
If the amount of the antimony compound used exceeds 20 parts, mechanical strength and thermal stability will decrease.

In the present invention, 2,2 '-(1,3-phenylene) -bis (2-oxazoline) 2,2'-(1,4-phenylene)-
Bis (2-oxazoline) is used, and these bisoxazoline compounds are used alone or as a mixture.

The amount of these bisoxazoline compounds to be blended is 0.05 to 5% by weight, preferably 0.05 to 5% by weight, based on the obtained flame retardant resin composition.
It is 0.1 to 3% by weight, particularly preferably 0.2 to 2% by weight. If the amount is less than 0.05% by weight, the heat stabilizing effect cannot be expected, and if it exceeds 5% by weight, the flame-retardant resin composition is melted when retained during molding. It is not preferable because the viscosity increases.

The flame-retardant resin composition of the present invention contains an alkali metal salt of ethylene / α, β-unsaturated carboxylic acid copolymer. By incorporating an alkali metal salt of the copolymer, thermal properties and mechanical properties are imparted at a relatively low mold temperature. The proportion of carboxyl groups neutralized with an alkali metal in the carboxyl groups contained in the alkali metal salt of the copolymer is preferably 5 to 50 mol%. The blending ratio of the copolymer is preferably 1 to 10 parts with respect to 100 parts of the polyethylene terephthalate resin. Specific examples of this copolymer include a copolymer of ethylene and acrylic acid, methacrylic acid, maleic acid, or other α, β-unsaturated carboxylic acid,
The olefin content is 50% by weight or more, and 5 to 50 mol% of the carboxyl groups in the copolymer are neutralized with an alkali metal. The preferred alkali metal is sodium.

In the flame-retardant resin composition of the present invention, if necessary,
Up to 200 parts, preferably 5 parts, of organic or inorganic reinforcing agent or filler per 100 parts of polyethylene terephthalate resin.
~ 200 parts can be blended. If the blending amount exceeds 200 parts, molding processing becomes difficult, and at the same time, the mechanical strength of the flame-retardant resin composition decreases. A preferred blending amount is 150 parts or less. The organic or inorganic reinforcing material or filler means a material added for the purpose of enhancing the function of the flame-retardant resin composition. Specifically, glass fiber, carbon fiber, asbestos,
Fiber reinforcements such as aromatic polyamide fibers, silicon carbide fibers, potassium titanate fibers and mineral fibers, calcium carbonate, magnesium carbonate, calcined clay, graphite, mica, talc, glass beads, metal powder, fluororesin powder and the like.

The flame-retardant resin composition of the present invention contains, in addition to the above components, additives generally used for thermoplastic flame-retardant polyester resins, such as antioxidants, colorants, plasticizers, resins other than polyester, and the like. You can also do it.

Polyethylene terephthalate resin, ethylene / α,
A composition obtained by mixing an alkali metal salt of a β-unsaturated carboxylic acid copolymer, a flame retardant, a bisoxazoline compound and, if necessary, other components is a uniform and easy-to-use composition by further melt mixing. It becomes a flame composition. It is convenient to use an extruder for melt mixing.

Next, the present invention will be described more specifically with reference to Examples and Comparative Examples.

Examples 1 to 3 In a mixed solvent in which phenol and 1,1,2,2, -tetrachloroethane were mixed at a weight ratio of 1: 1, the intrinsic viscosity measured at 25 ° C was 0.63, and the water content was 0.03% ( (% By weight, the same applies below) Polyethylene terephthalate 46 dried to the following
Part, 14 parts Pyrocheck 68PB (manufactured by Ferro Corporation) which is a flame retardant, 3 parts antimony trioxide as an antimony compound, and hyramine 1707 which is an alkali metal salt of an ethylene / α, β-unsaturated carboxylic acid copolymer ( Mitsui·
2 parts by mixing 5 parts of DuPont Polychemical Co., Ltd., 0.5 parts of Stabilizer Irganox 1010 (manufactured by Ciba Geigy) and 0.5 parts of Stabilizer Cynox 412S (manufactured by Cypro Kasei Co.) 2,2 '-(1,3-phenylene) -bis (2-oxazoline) was added to 0.5% each as shown in Table 1.
Parts, 1.0 parts, and 1.5 parts were added, and the mixture was stirred with a ribbon blender for 5 minutes. This compound is a twin-screw extruder PC manufactured by Ikegai Tekko KK
Melt-kneading was carried out using M-45 to obtain a flame-retardant resin composition in pellet form.

At this time, 30 parts of glass fiber (Glaslon 03JA-486A, manufactured by Asahi Fiber Glass Co., Ltd.) was added in the middle of the twin-screw extruder. The temperature conditions for extrusion were such that a temperature gradient of 280 ° C to 260 ° C was applied from the hopper side to the die side. For the other conditions, general conditions were selected so that extrusion could be stably performed. Then, the pellet resin was dried at 140 ° C. for 4 hours, and a test piece was prepared using an injection molding machine (manufactured by Toshiba Machine Co., Ltd., IS-75E). At this time, in order to evaluate the thermal stability, the injection molding temperature was set to a normal temperature (270 ° C) and a high temperature (300 ° C), and the mechanical strength of the obtained test piece was examined. Injection molding conditions are mold temperature 80 ℃, cooling time 30 seconds,
The primary injection pressure is 750 kg / cm ² , the secondary injection pressure is 400 kg / cm ² , and the injection time is 10 seconds. The thermal stability was evaluated by measuring the tensile strength and Izod impact strength without notch with a 270 ° C injection molded specimen.
This was done by comparing with a 00 ° C injection molded test piece. The results are shown in Table 1.

Example 4 Instead of the 2,2 ′-(1,3-phenylene) -bis (2-oxazoline) used in Example 1, 2,2 ′-(1,4-phenylene) -bis (2-oxazoline) ) A test piece was prepared in the same manner as in Example 1 except that 1.0 part was used, and the mechanical strength was measured to evaluate the thermal stability. The results are shown in Table 1.

Comparative Example 1 A test piece was prepared in the same manner as in Example 1 except that 2,2 '-(1,3-phenylene) -bis (2-oxazoline) was not added, and its mechanical strength was measured to obtain heat. Stability was evaluated. The results are shown in Table 1.

As is clear from Table 1, the flame-retardant resin composition of the present invention has high strength and excellent thermal stability.

Example 5 A test piece was prepared in the same manner as in Example 2 except that Irganox 1010 and Synox 412S were not used, and the mechanical strength was measured to evaluate the thermal stability. Table 2 shows the results.

Comparative Example 2 A test piece was prepared in the same manner as in Example 5 except that 2,2 '-(1,3-phenylene) -bis (2-oxazoline) was not used, and its mechanical strength was measured to obtain heat. Stability was evaluated. Table 2 shows the results.

The flame-retardant test of the test pieces (thickness: about 0.79 mm (1/32 inch)) obtained in Examples 1 to 5 and Comparative Examples 1 and 2 was UL-94 (Underwriters Laboratories, USA).
According to the standard), both were VO.

Example 6 A test piece was prepared in the same manner as in Example 1 except that 3 parts of sodium antimonate was used instead of the antimony trioxide used in Example 1, and the mechanical strength was measured to determine the thermal stability. evaluated. The results are shown in Table 3.

Comparative Example 3 A test piece was prepared in the same manner as in Example 6 except that 2,2 '-(1,3-phenylene) -bis (2-oxazoline) was not added, and its mechanical strength was measured. The thermal stability was evaluated. The results are shown in Table 3.

[Effects of the Invention] The flame-retardant resin composition of the present invention has high mechanical strength and is excellent in thermal stability at the same time, and thus is suitable for injection molding materials such as automobile interior materials and electronic precision parts. It can be used for.

Claims (9)

[Claims] 1. A composition comprising a flame retardant containing a polyethylene terephthalate resin, an alkali metal salt of an ethylene / α, β-unsaturated carboxylic acid copolymer and an organic halogen compound, and 2,2 ′-( 1,3-phenylene) -bis (2-
Oxazoline) or 2,2 '-(1,4-phenylene) -bis- (2-oxazoline) in an amount of 0.05 to 5.0% by weight. 2. The flame-retardant resin composition according to claim 1, wherein the flame-retardant agent comprises a halogen-containing aromatic compound in which halogen is directly bonded to an aromatic ring and an antimony compound. 3. The flame-retardant resin composition according to claim 2, wherein the antimony compound is an antimonate of a metal of Group I, II or VIII of the periodic table. 4. The flame retardant resin composition according to claim 3, wherein the antimonate is sodium antimonate and / or potassium antimonate. 5. The blending amount of the halogen-containing aromatic compound is 5 to 100 parts by weight of the polyethylene terephthalate resin.
The flame-retardant resin composition according to claim 2, wherein 50 parts by weight and the compounding amount of the antimony compound are 1 to 15 parts by weight. 6. An alkali metal salt of an ethylene / α, β-unsaturated carboxylic acid copolymer, wherein 5 to 50 mol% of the carboxyl groups contained in the alkali metal salt of the copolymer are neutralized with the alkali metal. Is a copolymer, and the amount of the alkali metal salt of the copolymer is polyethylene terephthalate resin.
The flame-retardant resin composition according to claim 1, which is 1 to 10 parts by weight with respect to 100 parts by weight. 7. The flame retardant resin composition according to claim 1, wherein the polyethylene terephthalate resin is polyethylene terephthalate. 8. A polyethylene terephthalate resin comprising polyethylene terephthalate and a compound of general formula (II): (In the formula, X ₉ is a —C (CH ₃ ) ₂ — group, —SO ₂ — group, —CO— group or —O— group, R ₂ is an alkylene group having 2 or 3 carbon atoms,
A block copolymer with a diol represented by the formula (n and m are integers of 5 to 15), wherein the content of the diol in the copolymer is 0.5 to 20% by weight. The flame-retardant resin composition according to item. 9. An organic or inorganic reinforcing material and / or a filler is blended in an amount of 5 to 200 parts by weight based on 100 parts by weight of a polyethylene terephthalate resin.
The flame-retardant resin composition according to item.