JPH0493354A - Polyamide resin composition - Google Patents

Abstract

PURPOSE:To improve flame retardance, tensile strength and elongation properties, impact characteristics, and resistance to blooming by compounding a polyamide resin, a specific modified polyester elastomer, and a flame retardant. CONSTITUTION:A polyester elastomer, such as a polyester-polyether block copolymer or a polyester block copolymer, is reacted with 0.01-20wt.% unsatd. carboxylic acid (e.g. maleic acid) in the presence of a free-radical initiator (e.g. benzoyl peroxide) to give a modified polyester elastomer. Then, 95-5 wt.% polyamide resin having an m. p. of 170 deg.C or higher and a relative viscosity of 1.8 or higher, 5-95wt.% the modified elastomer, and 5-60wt.% at least one flame retardant selected from the group consisting of a halogen compd. (e.g. decabromodiphenyl ether), a nitrogen compd. (e. g. melamine), and phosphorus compds. of formulas I, II, and III (wherein R1, R2, and R3 are each alkyl, haloalkyl, aryl. or haloaryl) are compounded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to non-blooming, flame-retardant polyamide compositions containing a flame retardant and a modified polyester elastomer.

The composition has excellent moldability and impact properties, especially tensile properties, and can be widely used for manufacturing automobile parts, electrical parts, mechanical parts, and various other molded products.

(Prior Art) Polyamide resins have been widely used in general household goods including electronic parts and automobile parts because they can be obtained relatively inexpensively and have excellent properties such as being easy to mold. However, polyamide resin is highly flammable and will burn easily once a fire occurs.
In particular, cable fires have a major impact on society.

Therefore, recently, flame retardation has been required by law in some of the fields in which these resins are used, such as electrical products, automobile interior parts, and textile products. For example, the MVSS-302 flame retardant regulations in the automobile industry in the United States are known, and in order to generally impart flame retardancy to polyamide resin, flame retardants are added when the resin is mixed, and inorganic flame retardants are Compounds, organic phosphorus compounds, etc. are known, but in order to exhibit flame retardant effects, it is necessary to increase the blending amount, which leads to a decrease in the physical properties of the resin due to poor dispersion,
There is a drawback that the blended flame retardant tends to precipitate in the form of powder on the resin surface after molding, which is a so-called blooming phenomenon.

It is also known that a rubber-reinforced polyamide resin with excellent flame retardancy can be produced by adding a flame retardant to a rubber-reinforced polyamide resin. With regard to polyamide resins, there are many complaints that the excellent properties originally possessed by rubber-reinforced polyamide resins before flame retardants are added, such as tensile strength and elongation properties and impact properties, are degraded by the addition of flame retardants. Ta.

(Problems to be Solved by the Invention) The present invention provides a flame-retardant polyamide composition that has poor tensile strength and elongation properties and impact properties, and is free from blooming, which could not be solved by the methods known in the prior art. This is what we are trying to provide.

(Means for Solving the Problems) In order to solve the above problems, the present inventors aimed to obtain a composition that has excellent physical properties such as impact properties and heat resistance, and does not cause blooming. As a result of intensive research efforts, we have finally completed the present invention. That is, the present invention provides a modified polyester elastomer obtained by reacting a polyester elastomer with a monomer selected from (A) a polyamide resin, and (B) an unsaturated carboxylic acid and an unsaturated carboxylic acid derivative, and (C) an organic Halogen compounds, nitrogen-containing compounds and the following - maximum (1) to (I
The above object is achieved by a polyamide composition characterized in that it contains one or more flame retardants selected from the phosphorus compounds represented by n).

R,0-P-OR3・・・・・・・・・・・・・・・
・・・・・・(1) R2 R10P ORa ・・・・・・・・・・・・
...River...(II)011! R, O-P -0R3・・・・・・・・・・・・・・・
(A) polyamide resin contained in the composition of the present invention Examples include nylon 6, nylon 6.6, and nylon 6.
9, nylon 6.10, nylon 6.12, nylon 6
/6.6, nylon 4,6, polyxylylene adipamide, polyhexamethylene terephthalamide, polyphenylene phthalamide, polyxylylene adipamide, polyxylene adipamide/hexamethylene adipamide, polyester Examples include amide elastomer, polyether amide elastomer, and dimer acid copolymerized polyamide. These may be used alone or in mixtures, or copolymers obtained with the heptamers forming these resins may also be used. The melting point of polyamide resin is 170'C
The above is preferable from the viewpoint of heat resistance. Usually, polyamide resin has a relative viscosity (JIS k6810-1970
(measured in 98% sulfuric acid) is preferably 1.8 or more, and more preferably 2.0 or more.

Polyester elastomers used in the preparation of the modified polyester elastomer contained in the composition of the present invention include polyester-polyether blank copolymers,
Examples include polyester block copolymers.

The above polyester-bolyether broth copolymer is
It is a block copolymer that has the properties of a rubber-like elastic body because polyester is used as a hard segment and polyether is used as a soft segment, and these segments are arranged alternately and repeatedly.

The acids and alcohols constituting such polyester units are mainly aromatic dicarboxylic acids and alkylene glycols having 2 to 15 carbon atoms, respectively. Specific examples of dicarboxylic acids include terephthalic acid, isophthalic acid, ethylenebis(p-oxybenzoic acid), naphthalene dicarboxylic acid, adipic acid, sebacic acid, 1,4-cyclohexanedicarboxylic acid, p-(β-hydroxyethoxy) Examples include benzoic acid. A specific example of glycol is
Ethylene glycol, propylene glycol, tetramethylene glycol, pentamethylene glycol, 2.2
-Dimethyltrimethylene glycol, hexamethylene glycol, decamethylene glycol, cyclohexane dimetatool, cyclohexane jetanol, benzenedimetatool, benzenedethanol and the like. As the above-mentioned dicarboxylic acids and glycols, those having a melting point of 200° C. or higher when made into a polyester having a molecular weight sufficient to have fiber-forming ability are suitable.

The polyether unit, which is the soft segment of the block copolymer, is a polyoxyalkylene glycol having an average molecular weight of about 500 to 5,000.

The monomer unit of this polyoxyalkylene glycol unit is an oxyalkylene group in which the alkylene group has 2 to 9 carbon atoms. Specifically, preferred examples include poly(oxyethylene) glycol, poly(oxypropylene) glycol, poly(oxytetramethylene) glycol, and the like. The polyether may be a single polyether, a random copolymer, a block copolymer, or a mixture of two or more polyethers. Furthermore, the polyether may have a small amount of aliphatic group, aromatic group, etc. in its molecular chain. It may also be a modified polyether containing sulfur, nitrogen, phosphorus, or the like.

The polyester-polyether block copolymer contains 1 to 85% by weight of polyether units, preferably 5 to 80% by weight.
% by weight, and the polyester units are 99 to 15
It is contained in an amount of 95 to 20% by weight, preferably 95 to 20% by weight.

Examples of polyester block copolymers include those obtained by reacting crystalline aromatic polyesters with lactones. Examples of the crystalline aromatic polyester include polymers mainly having ester bonds or ester bonds and ether bonds, having at least one type of aromatic group as a main repeating unit, and having a hydroxyl group at the end of the molecule. . The crystalline aromatic polyester preferably has a melting point of 150'C or more when formed into a polymer with a high degree of polymerization. When the polyamide resin composition of the present invention is used as a molding material, a polymer with a molecular weight of 5,000 or more is preferable, but when used for the adhesive side or coating, a polymer with a molecular weight of 5,000 or more is preferable.
The following may also be used. Suitable examples of crystalline aromatic polyesters can be found in homopolyesters, polyester ethers, copolyesters, copolyester ethers, and the like. Examples of homopolyesters include polyethylene terephthalate, polytetramethylene terephthalate, poly-1,4-cyclohexylene dimethylene terephthalate, polyethylene-2,6 naphthalate, and the like. Examples of polyesters include polyethyleneoxybenzoate, poly-p-phenylenebisoxyethoxyterephthalate, and the like. Examples of the copolymerized polyester or copolymerized polyester ether include polymers mainly having tetramethylene terephthalate units or ethylene terephthalate units and further having other copolymerization components. Such copolymerization components include tetramethylene terephthalate units, ethylene isophthalate units, tetramethylene adipate units, ethylene adipate units, tetramethylene sebacate units, ethylene sebacate units, L4-cyclohexylene dimethylene terephthalate units, and tetramethylene terephthalate units. methylene-p-oxybenzoate unit, ethylene-p
-oxybenzoate units, etc. are exemplified. The copolymerized polyester and copolymerized polyester ether preferably contain 60 mol% or more of tetramethylene terephthalate units or ethylene terephthalate units.

As the lactone, which is the other component forming the polyester type block copolymer, ε-caprolactone is most preferred, but enantlactone, cabrylolactone, etc. can also be used. Two or more types of these lactones may be used.

The polyester type block copolymer contains the crystalline aromatic polyester and lactones in a weight ratio of 97/3 to 5/9.
It is obtained by copolymerization using a ratio of 95%. Preferably, this weight ratio is 9515 to 30/70. In the above copolymerization, a catalyst is added as necessary, and the reaction is allowed to proceed by heating and mixing. The polyester elastomers (polyester-polyether block copolymers and/or polyester type block copolymers) thus obtained may be used alone or in combination of two or more.

The modifier which is reacted with the polyester elastomer to obtain the modified polyester elastomer is selected from unsaturated carboxylic acids and their derivatives.

Examples of unsaturated carboxylic acids include acrylic acid, methacrylic acid, α-ethyl acrylic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid, tetrahydrophthalic acid, methyltetrahydrophthalic acid, endo-bicyclo(2,2,1
) hept-5-ene-2,3-dicarboxylic acid (nadic acid), methyl-endocys-bicyclo(2,2,1
) hept-5-ene-2,3-dicarboxylic acid, methylnazinc acid), and the like.

Examples of derivatives of unsaturated carboxylic acids include derivatives of the above acids, such as acid halides, amides, imides, acid anhydrides, and esters. Specific examples include maleyl chloride, maleimide, maleic anhydride, m water'/ )laconic acid, monomethyl maleate, dimethyl maleate, and glycidyl maleate.

Among these, unsaturated dicarboxylic acids or unsaturated dicarboxylic anhydrides are preferably used. Particularly suitable are maleic acid, nadic acid, or acid anhydrides thereof.

These modifiers are used in an amount ranging from about 0.01 to about 20% by weight, preferably from about 0.02 to about 20% by weight, based on the polyester elastomer. If it is less than 0.01% by weight, the effect of improving the physical properties of the polyamide resin composition is small. 2
If it exceeds 0% by weight, gelation tends to occur during the graft reaction.

The method of reacting the modifier with the polyester elastomer (graft copolymerization) is not particularly limited, but it is desirable that the resulting modified polyester elastomer does not contain undesirable components such as gel. A decrease in the polyester elastomer is undesirable because processability deteriorates. Specifically, for example, by blending the above polyester elastomer, a modifier, and a radical generator and melt-kneading, a graft reaction occurs and a modified polyester elastomer is obtained. . As a radical generator,
Known organic peroxides or diazo compounds may be used.

Specific examples include benzoyl peroxide, dicumyl peroxide, di-t-butyl peroxide, t-butylcumyl peroxide, cumene hydroperoxide, and azobisisobutyronitrile. The amount of radical generator used is 0.05% by weight or more, preferably 0.1% by weight based on the polyester elastomer.
~1.5% by weight.

In the polyamide resin composition of the present invention, polyamide resin (^) and modified polyester elastomer (B)
The weight ratio (A)/(B) is preferably from 9515 to 5/95, and more preferably from 90/10 to 10/90. When the weight ratio of the modified polyester elastomer is smaller than 9515, impact resistance, rigidity, etc. are not improved, and when the weight ratio of the modified polyester elastomer is larger than 5/95, water resistance etc. are deteriorated.

Next, the flame retardant (C) to be blended in the present invention is preferably a compound with excellent heat resistance, considering the heat history received during the molding process of the polyamide composition. Compound and the above-maximum (1)
One or more flame retardants selected from the phosphorus compounds represented by (II) to (II) are employed, and organic halogen compounds are particularly preferred in the present invention.

The organic halogen compound refers to a compound that is generally treated as a halogen flame retardant, but in consideration of the heat history received during the molding process of the polyamide composition, aromatic halogen compounds with excellent heat resistance are preferred.

Specific examples include halogenated polycarbonates such as decabromodiphenyl ether, brominated polycarbonate obtained from tetrabromobisphenol A and phosgene,
Brominated copolymerized polycarbonate obtained from tetrabromobisphenol A, bisphenol A and phosgene, halogenated epoxy compounds such as brominated epoxy compounds obtained from tetrabromobisphenol A and epichlorohydrin, brominated polystyrene, brominated polyphenylene oxide, etc. I can do it.

Only one type of these may be used (or two or more types may be used in combination).

The nitrogen-containing compound is one or more nitrogen-containing compounds selected from the group consisting of melamine, benzoguanamine, dimethylol urea, cyanuric acid, and melamine cyanurate. Among these nitrogen-containing compounds, melamine,
Melamine cyanurate is preferably used. The nitrogen-containing compound includes copper halide and metaxylylene diamine, hensylamine, 2-mercabuthenzothiazole, or
It is more preferable to use a complex with a nitrogen-containing compound such as 2-mercaptobenzimidazole, or a heat-resistant composite consisting of copper halide and potassium halide.

As a phosphorus compound, specific examples of the compound represented by the maximum (1) above include trimethyl phosphate, triethyl phosphate, triphenyl phosphate, tricresyl phosphate, talesyl diphenyl phosphate, diphenyl octyl phosphate, tributyl phosphate, tris( 3-chloroethyl) phosphate, tris(dichloropropyl) phosphate, tris(
2,3-dibromopropyl) phosphate, tris(bromochloropropyl) phosphate, tris(2-bromoethyl) phosphate, trioctyl phosphate,
Examples include tributoxyethyl phosphate.

Specific examples of the compound represented by general formula (II) include:
Examples include trimethyl phosphite, triethyl phosphite, tris(2-chloroethyl) phosphite, and triphenyl phosphite.

Specific examples of the compound represented by the general formula (I[I) include dimethyl phenylphosphonate, diethyl phenylphosphonate, dibutyl phenylphosphonate, dimethyl benzylphosphonate, diethyl benzylphosphonate, bis(hydroxyethyl)benzylphosphonate, Bis(2-bromoethyl) 2-bromoethylphosphonate and the like can be mentioned.

The compounds represented by -maximum (1) to (nl) may be used alone or in combination of two or more.

Furthermore, in the present invention, it is preferable to add a flame retardant additive, and examples of the flame retardant additive include antimony dioxide, magnesium oxide, molybdenum oxide, tin oxide, zirconium oxide, and zinc oxide.

Further, other flame retardants such as chlorinated paraffin, chlorinated polyethylene, perchloropentacyclodecane, etc. may be used in combination as long as the properties of the composition of the present invention are not impaired.

The blending amount of the flame retardant (C) is 5 to 60% by weight, preferably 10 to 50% by weight, based on the total of components (A) to (C) as 100% by weight. If the blending amount is less than 5% by weight, the flame retardance is not sufficient and there is a disadvantage that it is relatively easy to burn, which is not preferable.

On the other hand, if the blending amount exceeds 60% by weight, the physical properties of the resin will deteriorate due to poor dispersion, and the blooming phenomenon in which the blended flame retardant will precipitate in powder form on the resin surface after molding will tend to occur.
Furthermore, the Izot impact strength and tensile strength and elongation are also lowered, which is not preferable.

Next, as a method for producing the composition of the present invention, (A) polyamide, (B) modified polyester elastomer and (C
) The flame retardant may be mixed using a V-type blender, Henshil mixer, super mixer, etc., and then directly melt-molded, or alternatively, the flame retardant may be melt-mixed using an extruder, kneader, etc., then formed into a tin, and then molded.

The composition of the present invention may optionally contain a mold release agent, a coupling agent, an antioxidant, an ultraviolet absorber, a photoprotectant, a phosphite stabilizer, a peroxide dispersant, a basic adjuvant, Nucleating agents, plasticizers, lubricants, antistatic agents, inorganic fillers, pigments, dyes,
It is also possible to blend carbon black or the like.

(Function) (B) Modified polyester elastomer is obtained by grafting polyester elastomer with a modified side selected from unsaturated carboxylic acids and derivatives thereof, so that this and polyamide resin (A) are It is presumed that by mixing under heating, the graft-reacted carboxylic acid and its derivatives partially react with the amino end groups of the polyamide resin. By this reaction,
It is presumed that homogeneous compatible dispersion of the polyamide resin and the modified polyester elastomer is promoted, and in this way heat resistance can be added while maintaining the excellent properties of the polyamide resin.

In addition, when a flame retardant is added, the polar groups in the flame retardant react with the end groups of the nylon or polyester elastomer, which improves compatibility and prevents the blooming phenomenon.
Further, an improvement in flame retardancy was also observed, and there seemed to be almost no deterioration in tensile properties and impact properties.

(Example) The present invention will be specifically explained using Examples, but the present invention is not limited thereto. Incidentally, flame retardancy, plate-out, blooming and mechanical properties shown in Examples were evaluated by the following measurement methods.

(1) Flame retardant length 5 in. width 1/2 in. thickness 1/32 in.
, 1/16"l/8" test piece was prepared and UL-94 (
US Under Writers Laboratory
It was measured according to the method of the standard defined by ies Inc.

(2) After plate-out of a disk with a diameter of 100 ym and a thickness of 3.2 mg for 50 seconds in a mirror mold, the surface of the mold and the surface of the molded product were observed with the naked eye.

(3) Blooming A disk with a diameter of 100 m and a thickness of 3.2 mm was prepared and left in a 40'C190% atmosphere for one week, and the surface condition was observed with the naked eye.

(4) Mechanical properties Tensile strength is in accordance with ASTM 0638, and isot impact strength is 2.5 XI/2Xl/2inch.
Each test piece was measured according to the method specified in ASTM D-256.

In this example, the polyamide resin has a relative viscosity of 2.53.
(in 98% sulfuric acid; 1 g/100 dl, 25°C)
Nylon 6 with a relative viscosity of 2.51, and polymethaxylylene adipamide with a relative viscosity of 2.10 (
MXD-6), these resins were heated at 100'C for 1
It was used after vacuum drying for 6 hours.

Examples of polyester elastomers include: polyether-polyester elastomer of polytetramethylene glycol and polytetramethylene terephthalate (Perbrene P150B manufactured by Toyobo Co., Ltd.);
and (2) A polyester block copolymer of polycaprolactone and polytetramethylene terephthalate (Perbrene S-1000 manufactured by Toyobo Co., Ltd.) was used.

Table 1 also shows the flame retardants and alkali flame retardant aids used here.

Table 1: Production Examples Preparation of modified polyester elastomer 100 parts by weight of the above (1) or (2), 0.5 parts by weight of maleic anhydride, and 0.3 parts by weight of digmeal peroxide were uniformly mixed in a mixer. This mixture was supplied to a twin-screw extruder, and a maleic anhydride modification reaction was carried out at a cylinder temperature of 200 to 230°C. The reaction product thus obtained was dried in a vacuum dryer at 80°C for 12 hours to obtain a modified polyester elastomer (■' or ■').

Examples 1 to 16, Comparative Examples 1 to 9 After tri-blending the above polyamide resin, the modified polyester elastomer ■' or ■' obtained in the above production example, and a flame retardant at the ratio shown in Table 2, 30 Pellets were produced using a φ twin screw extruder. The cylinder temperature at that time is 250°C in the case of nylon 6;
．． 280 °C for 1MXD-6
60"C.The resulting pellets were heated at 70°C for 1
After vacuum drying for 6 hours, each test piece was prepared using the same polymer temperature and mold 70'C as in the twin-screw extrusion. The results are shown in Table 2.3.

As is clear from Table 2.3, the compositions of the present invention obtained in Examples 1 to I6 have excellent properties in all aspects such as tensile strength and elongation, impact strength, flame retardance, and blooming property. It can be seen that Further, in Comparative Example 1.6, the flame retardance was not improved because no flame retardant was blended, and in Comparative Examples 2 to 4.5.
In No. 7, since the polyester elastomer was not modified, the tensile strength and elongation and impact strength were low, and the effect of the flame retardant was also extremely low as I(B, V-2).

Examples 11 to 16 and Comparative Example 8.9 use a nitrogen compound as a flame retardant;
Since Sample No. 9 uses an unmodified polyester elastomer, it can be seen that the tensile strength and elongation, impact strength, and flame retardance are also low.

(Effects of the Invention) The composition of the present invention is a flame-retardant BoIJ amide composition that does not cause blooming and has excellent physical properties such as tensile strength and elongation and impact resistance. It can be widely used for automotive parts, electronic parts, and general household goods, making it a great contribution to industry.

Patent applicant: Toyobo Co., Ltd.

Claims (1)

[Claims] (A) a polyamide resin; (B) a modified polyester elastomer obtained by reacting a monomer selected from unsaturated carboxylic acids and unsaturated carboxylic acid derivatives with a polyester elastomer; and (C) A polyamide resin composition comprising one or more flame retardants selected from organic halogen compounds, nitrogen-containing compounds, and phosphorus compounds represented by the following general formulas (I) to (III). ▲There are mathematical formulas, chemical formulas, tables, etc.▼・・・・・・( I
) ▲There are mathematical formulas, chemical formulas, tables, etc.▼・・・・・・(II) ▲There are mathematical formulas, chemical formulas, tables, etc.▼・・・・・・(III
) (However, in the formula, R_1, R_2 and R_3 each represent the same or different alkyl, haloalkyl, aryl and haloaryl groups.)