JPS58108248A - Flame retardant polyester resin composition - Google Patents

Abstract

PURPOSE:The titled composition, prepared by kneading red phosphorus coated with a thermosetting resin and a reinforcing filler with a thermoplastic polyester resin, having high flame retardancy without deteriorating the heat resistance, etc. of the polyester resin, and suitable for electrical parts, etc. CONSTITUTION:A flame retardant polyester resin composition prepared by kneading 99-34pts.wt. thermoplastic polyester resin, e.g. a resin consisting of a dicarboxylic acid component containing at least 90mol% and a diol component containing at least 90mol% ethylene glycol, with 1-25pts.wt. red phosphorus coated with a thermosetting resin, e.g. usually phenol-formalin resin, and 0- 65pts.wt., preferably 10-55pts.wt., reinforcing filler, e.g. glass fibers.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a polyester resin composition having a high degree of flame retardancy. More specifically, the present invention relates to a thermoplastic polyester resin composition coated with a thermosetting resin and made flame retardant using red phosphorus.

Thermoplastic polyester resins have a high softening point and excellent electrical and mechanical properties, including heat resistance, chemical resistance, and light resistance, so they are widely used in fibers, films, and molded products. .

However, it has poor flame retardancy, causing problems especially when applied to building material parts and electrical parts, and may be subject to significant limitations in terms of use.

Conventionally, it has been known to use halogen compounds together with flame retardant aids such as antimony trioxide to make thermoplastic polyester resins flame retardant. This often results in poor dispersion, resulting in a decrease in mechanical properties such as tensile strength, and leaching of the flame retardant onto the surface of the molded product, so-called pre-deinking. In order to improve this drawback, for example, Japanese Patent Application Laid-Open No. 1986-
459B states that S-flammability can be imparted to polyester by adding red phosphorus. However, since red phosphorus is extremely susceptible to chemical reactions, it is not only difficult to handle, but compositions containing red phosphorus also have the drawbacks of poor thermal stability and reduced electrical properties. .

As a result of intensive studies based on this viewpoint, the present inventors surprisingly found that by closely blending red phosphorus coated with a thermosetting resin with a thermoplastic polyester resin, a high degree of flame retardancy was achieved. The inventors have discovered that it is possible to obtain a composition that has excellent heat resistance stability and electrical properties, and has arrived at the present invention.

That is, the present invention contains (99 to 34 parts by weight of an al thermoplastic polyester resin, (b) 1 to 25 parts by weight of red phosphorus coated with a thermosetting resin, and (c) 0 to 65 parts by weight of a reinforcing filler. The gist is a flame-retardant polyester resin composition.

The details will be explained below.

In the present invention, the thermoplastic polyester resin includes a dicarboxylic acid component in which at least 90 mol% is terephthalic acid, and at least 90 mol% mateca ethylene glycol, propane-1,3-diol, butane-1,4-
diol, pentane-1,5-diol, hexane-1
, 6-diol, cyclohexane-1,4-dimetatool.It is obtained by direct esterification or transesterification and polycondensation with the diol component. Deer made of thermoplastic polyester resin! 0 to 10 mol% of the levonic acid component may be other aromatic dicarboxylic acids having 6 to 14 carbon atoms, aliphatic dicarboxylic acids having 4 to 8 carbon atoms, or alicyclic dicarboxylic acids having 8 to 12 carbon atoms. . Examples of such dicarboxylic acids are phthalic acid, isophthalic acid, 2.6-naphthalene dicarboxylic acid%4. Examples include A'-diphenyldicarboxylic acid, diphenylethane-4,4'-dicarboxylic acid, adipic acid, sebacic acid, and cyclohexanedicarboxylic acid. Also, 0 to 10 mol% of the diol component
is the number of carbons! 1 to 10 other aliphatic diols, carbon number 6 to
15 other alicyclic diols or aromatic diols having 6 to 12 carbon atoms. Examples of such diols include 2,2-dimethylpropane-1,3-diol,
2.2-bis-(4'-hydroxyschiff-11hexyl)
-propane, 2,2-bis-(4'-hydroxyphenyl)propane, hydroquinone, and the like. Furthermore,
an oxycarboxylic acid, such as ε-oxycaproic acid, in an amount of up to 10 mol% of the dicarboxylic acid component and diol component;
Hydroxybenzoic acid or the like may be copolymerized.

Of course, the thermoplastic polyester resin may be branched with trivalent or tetravalent alcohols or tribasic or tetrabasic acids; examples of suitable branching agents include trimesic acid, trimellitic acid, trimellitic acid, Examples include methylolpropane and pentaerythritol.

From an industrial standpoint, polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, etc. are preferred, and they may be used alone or in a blend of two or more. Furthermore, for the purpose of increasing crystallinity, organic acid salts such as sodium acetate, sodium benzoate, thorium hydrogen phthalate, disodium phthalate, magnesium stearate, sodium stearate, calcium stearate, etc.; Nucleating agents such as inorganic salts such as sodium, calcium carbonate, calcium silicate, magnesium silicate, calcium sulfate, and notrium sulfate; metal oxides such as zinc oxide, magnesium oxide, and titanium oxide are added. Alternatively, polyethylene glycol-1 may be copolymerized or mixed with polypropylene glycol, polyalkylene glycol such as polytetramethylene glycol, dibasic acid such as adipic acid and diol such as butane diol. -1 may contain aliphatic polyester oligomers, so-called ionomers such as sodium salts of ethylene/acrylic acid copolymers, etc.; A compound having a structure having an organic acid metal salt at the terminal may be contained. Particularly preferred are resins based on polyethylene terephthalate that increase the crystallization rate (by containing a nucleating agent, polyalkylene glycol, a compound having a structure having an organic acid metal salt at the terminal end of the polyalkylene glycol, etc.). . Furthermore, for the purpose of improving the mechanical and electrical properties of the thermoplastic polyester, it may contain polyamide polymers, polycarbonate polymers, etc., and diene rubbers, acrylic rubber polymers, butyl rubber polymers, etc. It may also contain thermoplastic rubbers such as polymers, ethylene-propylene rubber copolymers, ethylene-acetic acid arsenic copolymers, urethane rubbers, epichlorohydrin rubbers, and silicone rubbers.

In the present invention, red phosphorus coated with a thermosetting resin refers to red phosphorus whose surface is uniformly coated with a thermosetting resin. The thermosetting resin referred to herein may be any resin that can uniformly cover red phosphorus, and is usually selected from phenol-formalin, urine s-formalin, melamine-formalin, alkyd, and the like. The thermosetting resin raw material is added to an aqueous red phosphorus dispersion while stirring and then polymerized, or the initial condensate of the resin raw material prepared in advance is added to the red phosphorus aqueous dispersion while stirring and then polymerized. According to the method described above, red phosphorus can be coated with a thermosetting resin. During this coating process, a dispersion stabilizer or a red phosphorus stabilizer such as magnesium hydroxide may be added. After polymerization, it is filtered, washed with water, and dried to be used as a flame retardant.

In this way, red phosphorus coated with thermosetting resin is cut off from contact with air and moisture, and acquires strong resistance against them. Furthermore, since it is coated with thermosetting resin, the coating does not dissolve even when melted and mixed with thermoplastic polyester resin, so there is no exposed layer of red phosphorus, and there is no resistance to air or moisture. In addition, the increased compatibility ensures uniform dispersion.

The amount added to the composition to exhibit a sufficient flame retardant effect is 1 to 25 parts by weight, preferably 2 to 15 parts by weight. If the amount added is less than 1 part by weight, the flame retardant effect will be small, and if it exceeds 25 parts by weight, the quality may become unstable. In addition, red phosphorus coated with a thermosetting resin may be used alone, and if necessary, other flame retardants such as halogenated diphenyl ether compounds, halogenated polycarbonate compounds, halogenated It is also possible to develop a synergistic effect by using polyphenylene oxide compounds, halogen-containing S-) riazine compounds, halogenated bisphenol type epoxy resins, etc. In addition, if necessary, flame retardant aids such as trioxide may be added. It can also be produced by using antimony, antimony pentoxide, antimony tartrate, etc.

In the present invention, the reinforcing filler refers to a fibrous, plate-like, or granular inorganic filler, and by blending these, mechanical strength, heat resistance, and dimensional stability can be further enhanced. Specific examples include glass fiber, mineral fiber, carbon fiber, silicon carbide fiber, boron carbide fiber, potassium titanate fiber, gypsum fiber, mica, talc, kaolin, clay, asbestos, calcium silicate, calcium sulfate, calcium chloride, etc. In particular, glass fiber, mica,
Talc and mineral fiber are preferred, and these may be used alone or in combination of two or more.

Further, the surface may be treated with a silane coupling agent or the like in order to improve the affinity with the resin.

The blending amount is usually 0 to 65 parts by weight, preferably 10 to 55 parts by weight considering mechanical strength, heat resistance, and fluidity.
Can be determined based on quality settings.

To produce the composition of the present invention, a thermoplastic polyester resin, a red phosphorus coated with a thermosetting resin, and a reinforcing filler may be mixed by a known method. That is, examples include a method of adding and blending the thermoplastic polyester resin during production, a method of mixing and extruding using an extruder, and the like.

Other additives such as thermal antioxidants, light stabilizers, pigments, dyes, plasticizers, lubricants, etc. may be added to the composition of the present invention to the extent that flame retardancy is not impaired.

In this way, it is possible to obtain a composition that has a high degree of flame retardancy, as well as excellent heat stability and electrical properties.

The composition of the present invention can be widely used for molding various molded parts, pipes, containers, etc., and can be particularly suitably used for electrical parts, building material parts, automobile parts, etc., and can also be used for fibers, films, and sheets. .

The present invention will be described below with reference to Examples, but the present invention is not limited to these Examples. In the examples, the tensile strength of the molded product was ASTM-D63B, the heat distortion temperature (1B, b kg/d) was ASTM-D6AB,
Flame retardancy is UL-94 vertical test method, arc resistance is ASTM
- Measured by a method based on D7195. Heat resistance stability was evaluated by tensile strength retention after being left in an oven at 15° C. for 7 days. Further, the amounts added in each example are parts by weight.

Example 1 [Manufacture of red phosphorus coated with phenolic resin] 200 ml of water was placed in an autoclave equipped with a stirrer having an internal volume of s o l l, and 100 f of finely ground red phosphorus was suspended. Add 3g of phenol to this.

A 37% formalin aqueous solution (phenol/formaldehyde (molar ratio) = 1/2) was added and dissolved, heated to 80° C. with strong stirring, and a small amount of phosphoric acid was added. 1 hour,
After continuing stirring while maintaining the same temperature, cool to room temperature.
The crime was washed away.

The obtained furnace slag was heated in an open oven at 140"C for 3 hours to complete curing of the resin and remove water. The phosphorus content of the obtained red phosphorus was 85%. Red phosphorus coated with resin was produced (hereinafter abbreviated as coated red phosphorus).

Examples 2 to 4, Comparative Example 1 Polyethylene terephthalate, coated red phosphorus of Example 1,
Mineral fiber (processed mineral fiber), fiber length 3
Parrot glass fibers were extruded and mixed in various ratios and then injection molded to obtain test pieces. As shown in Table 1, it did not impair mechanical properties, had a high degree of flame retardancy P, and exhibited excellent arc resistance and heat resistance stability.

As Comparative Example 1, Table 1 also shows the case where ordinary red phosphorus was added to the coated red phosphorus. In this case, although flame retardancy can be imparted, it is clear that arc resistance and heat resistance stability are at a low level.

Table 1 Examples 5 to 6 Polyethylene terephthalate, the coating material of Example 1, glass fiber with a fiber length of 3M, and talc were extruded and mixed in various ratios, and then test pieces were prepared by injection molding. Table -
As shown in No. 2, it did not impair its physical properties, had a high degree of flame retardancy, and had extremely excellent arc resistance and heat resistance stability.

Table-2

Claims (1)

[Claims] 1. ral thermoplastic polyester lLl-based resin 9
9 to 34 parts by weight, (bl red phosphorus coated with thermosetting resin 1 to 2
5 parts by weight, and (a) 0 to 65 parts by weight of a reinforcing filler. 2. Claim 1, wherein the thermoplastic polyester resin is mainly polyethylene terephthalate.
Compositions as described in Section.