JPH03237162A - Resin composition - Google Patents

Abstract

PURPOSE:To obtain a resin composition, composed of a modified polyphenylene sulfide resin, a specific elastomer and an inorganic hydrate, good in appearance of molded products and excellent in impact strength, thermal shape stability, mechanical properties and flame retardance. CONSTITUTION:A resin composition obtained by blending (A) a modified polyphenylene sulfide resin prepared by melt kneading 95-99.9wt.% polyphenylene sulfide resin with 0.1-5wt.% nonblock type polyfunctional isocyanate compound (e.g. 4,4'-diphenylmethane diisocyanate) with (D) an elastomer selected from (B1) copolymers composed of 50-90wt.% ethylene, 5-49wt.% alkyl alpha,beta-unsaturated carboxylate and 0.5-10wt.% maleic anhydride, (B2) epoxy group-containing olefinic copolymers and (B3) ionomer resins and (C) an inorganic hydrate at (50:50)-(95:5) weight ratio of the components (A):(B) and (5:100)-(150:100) weight ratio of the components (C):(A+B).

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a thermoplastic resin composition having excellent flame retardancy, heat resistance, mechanical properties, and moldability.

The resin composition of the present invention can be molded by injection molding or extrusion molding into molded articles useful in the automobile, electrical, electronic, and mechanical fields.

[Conventional technology]

The field of application of engineering plastics has been expanding more and more in recent years, and in particular, their use in the automobile, electrical, and electronic fields has increased significantly. Along with this, demands from users for plastics have become more versatile and highly functional, and meeting these demands has become a technological challenge. However, these demands for increased versatility and higher functionality cannot be met sufficiently with a single material alone, and for this reason, polymer alloys have been increasingly used to meet these demands.

Polyphenylene sulfide resin (hereinafter referred to as PPS)
The resin composition consisting of elastomer and elastomer is a well-known polymer alloy, and was developed against the background of the above-mentioned requirements. In other words, although PPS is known as a resin with excellent flame retardancy, heat resistance, and chemical resistance, its impact strength is not always satisfactory, and for this reason, impact resistance can be improved by alloying it with elastomer. Improving. For this purpose, the present inventors previously found that modifying polyphenylene sulfide resin with an unblocked polyfunctional isocyanate compound improves its compatibility with certain specific elastomers.
They discovered that the impact resistance was significantly improved and filed a patent application (for example, Japanese Patent Application No. 1-187458).

However, the flame retardance of such a resin composition is reduced due to the alloyed elastomer, and the flame retardancy, which is an original characteristic of PPS, is lost.

In addition, conventionally, in order to have flame retardancy, halogen atoms were added.
Alternatively, it has been known to use organic flame retardants containing phosphorus atoms, but this poses a problem of metal corrosion in the barrel and screw of the extruder, as well as the cylinder and mold of the molding machine, which has a negative impact on productivity. Furthermore, in recent years, in order to minimize damage in the event of a fire, it has become necessary to consider low smoke emission and low toxicity of combustion gas in addition to flame retardancy.

[Problem to be solved by the invention]

In view of the above circumstances, the object of the present invention is to maintain the excellent properties of a resin composition composed of PPS and an elastomer, improve flame retardancy, reduce metal corrosion, and further improve smoke generation in the event of a fire. The object of the present invention is to obtain a resin composition in which the toxicity of combustion gas is low.

Means and action for solving problem C] As a result of intensive research for the purpose, the present inventors have developed a modified polyphenylene sulfide resin ( A), an ethylene copolymer consisting of 50 to 90% by weight of ethylene, 5 to 49% by weight of α,β-unsaturated carboxylic acid alkyl ester, and 0.5 to 10% by weight of maleic anhydride, and an epoxy group-containing olefin copolymer at least one elastomer selected from ionomer resins (
B) and inorganic hydrate (C) as (A)/(B) =50150-9515(C)/1(
A) + (B)) = 5/100- 150/10
The inventors have discovered that a resin composition characterized by a weight ratio of 0 can achieve the above object, and have arrived at the present invention.

The PPS used in the present invention has a structural formula: PPS obtained by any method can be used in the present invention.

Furthermore, less than 30 mol% of the repeating units of PPS can be composed of repeating units having the following structural formula, etc.

It is a polymer containing 70 mol % or more, more preferably 90 mol % or more of the repeating unit represented by the following. If the repeating unit is less than 70 mol %, heat resistance will be impaired, so it is not preferable.

PPS is generally a polymer with a relatively small molecular weight obtained by the production method typified by Japanese Patent Publication No. 45-3368, and an essentially linear polymer obtained by the production method typified by Japanese Patent Publication No. 52-12240. There are relatively high-molecular polymers, etc., and the polymers obtained by the method described in Japanese Patent Publication No. 45-3368 are treated by heating in an oxygen atmosphere after polymerization or by adding peroxides etc. It is also possible to use a highly polymerized PPS by adding a crosslinking agent and heating it, and the melt viscosity of the PPS used in the present invention is not particularly limited as long as it is possible to obtain a molded product, but it depends on the toughness of the PPS itself. In terms of properties, those with 100 poise or more are preferably used, and in terms of moldability, those with io, ooo voids or less are more preferably used. Particularly preferred is a range of 1.000 to 5,000 poise.

Furthermore, for the purpose of controlling the degree of crosslinking of PPS, common peroxide crosslinking agents and crosslinking accelerators such as thiophosphinic acid metal salts described in JP-A-59-131650,
or JP-A-58-204045, JP-A-58-
It is also possible to incorporate crosslinking inhibitors such as dialkyltin dicarboxylate and aminotriazole described in JP-A No. 204046 and the like.

Methods for incorporating polyfunctional isocyanates into PPS are already known. For example, JP-A-57-1689
Publication No. 45 discloses adding 0.1 to 10% by weight of isocyanate to PPS.

In the present invention, polyphenylene sulfide resin 95-99
, 9% by weight and 0.1 to 5% by weight of an unblocked polyfunctional isocyanate compound to form a modified PPS.
(A).

The non-blocked polyfunctional isocyanate compounds used in the present invention include isocyanate compounds having two or more non-blocked isocyanates in one molecule,
General formula: % formula %) There are unblocked polyfunctional isocyanates and isothiocyanate compounds.

- Types used in boat fishing can be broadly divided into aliphatic and aromatic types, and modified types include dimeric type, trimer type (isocyanurate type), multimeric type, carbodiimide modified type, etc. The invention can use any isocyanate compound.

However, block-type isocyanates (also called mask-type isocyanates), i.e., blocks in which isocyanates are reacted in advance with acidic sodium sulfite, phenol, cresol, lactams, heterocyclic compounds, hydrocyanic acid, sulfites, etc., and then regenerated at high temperatures. Type isocyanate compounds are not included because they have little effect for this purpose.

Specific compounds include, for example, 4,4°-diphenylmethane diisocyanate, 4,4°-diphenylethane diisocyanate, 4.4°-diphenylpropane diisocyanate, carbodiimide-modified diphenylethane diisocyanate, naphthylene-1,5-diisocyanate, and toluene. Diisocyanate, dimerized toluene diisocyanate, hexamethylene diisocyanate, trimerized hexamethylene diisocyanate, pentamerized hexamethylene diisocyanate, heptamerized hexamethylene diisocyanate, polymethylene polyphenyl polyisocyanate, phenylene diisocyanate, 3.3゛-dimethyldiphenylmethane- 4,4°-diisocyanate, 3,
3'-dimethyl-4,4'-diphenylene diisocyanate, 3,3-bitoluene 4,4'-diisocyanate, xylene diisocyanate, isophorone diisocyanate, triphenylmethane triisocyanate, lysine diisocyanate, dicyclohexyldimethylmethane diisocyanate, diethyl fuma rate diisocyanate, triisocyanatebenzene, triisocyanatenaphthalene, bis(4-isocyanatephenyl)ether, bis(4-isocyanatephenyl)thioether, bis(4-isocyanatephenyl)sulfone, tris(4-isocyanatephenyl)phosphite, tris( There are non-blocked polyfunctional isocyanate compounds such as 4-isocyanate phenyl) phosphate, compounds with corresponding isothiocyanates, and the above-mentioned aromatic isocyanate compounds added with water.

The melt kneading in the present invention can be carried out using a known device, such as a kneader roll mill or an extruder, which is commonly used for kneading resin melts. Types of extruders include single-screw, twin-screw, co-kneader, etc., and the modified P P S (A) of the present invention can be obtained using any of the extruders.

The kneading temperature is higher than the melting point of PPS, and sufficient kneading is possible within the commonly used range of 280 to 340°C. Further, it is preferable that PPS be pre-dried as a pretreatment and kneading be performed in an inert gas atmosphere.

The melt kneading is carried out at a ratio of 595 to 99.9% by weight of PP, preferably 97 to 99% by weight, and 0.1 to 5% by weight, preferably 1 to 3% by weight of an unblocked polyfunctional isocyanate compound. The isocyanate compound is PP
It is thought that it functions effectively as a crosslinking agent for crosslinking S, but this mixing ratio is 0.1% by weight.
If it is below, the reforming effect in the present invention will decrease, and conversely
If it exceeds % by weight, it tends to become brittle, probably because the degree of crosslinking increases too much.

In the present invention, in order to improve the impact resistance of PPS, 50 to 90% by weight of ethylene, 5 to 49% by weight of α,β-unsaturated carboxylic acid alkyl ester, and 0% of maleic anhydride are used.
．． At least one type of elastomer selected from ethylene copolymers, epoxy group-containing olefin copolymers, and ionomer resins containing 5 to 10% by weight is used.

The monomer components of the ethylene copolymer used in the present invention are ethylene, α, β-unsaturated carboxylic acid alkyl ester, and maleic anhydride, and the ethylene content is 50 to 90% by weight, preferably 60 to 85% by weight. %, α,β-unsaturated carboxylic acid alkyl esters from 5 to 49% by weight, preferably from 7 to 45% by weight, maleic anhydride from 0.5 to 10% by weight, preferably from 1 to 8% by weight.

α,β-Unsaturated carboxylic acid alkyl ester is an unsaturated carboxylic acid having 3 to 8 carbon atoms, such as acrylic acid,
Alkyl esters such as methacrylic acid, specific examples include methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, t-butyl acrylate, isobutyl acrylate, and methacrylate. Methyl acid, ethyl methacrylate,
Examples include n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, t-butyl methacrylate, and isobutyl methacrylate. Among these, ethyl acrylate, n-butyl acrylate, and methyl methacrylate are particularly preferred.

As a guideline for the molecular weight of these copolymers, 190"C,
Melt index values under a load of 2,16 kg can be used. The melt index value of the copolymer used is 0.1 to 1,000, preferably 0.2.
-500, more preferably 1-100.

These copolymers are commercially available from Sumira CPF Chemical Industry Co., Ltd. under the name "Bondine".

Epoxy group-containing olefin copolymers are produced by known methods such as direct copolymerization of glycidyl esters of α,β-unsaturated carboxylic acids and olefins, or graft copolymerization with polyolefins and polyolefin copolymers.

The glycidyl ester of α,β-unsaturated carboxylic acid used here has the general formula (wherein R is a hydrogen atom or a lower alkyl group).
Examples include glycidyl acrylate, glycidyl methacrylate, glycidyl ethacrylate, etc. Among them, glycidyl methacrylate is preferably used.

Such epoxy group-containing olefin copolymers usually contain 0.0
It ranges from 1 to 20% by weight, preferably from 0.05 to 5% by weight. -These epoxy group-containing olefin copolymers are commercially available from Sumira Chemical Co., Ltd. under the name "Bond First."

The method for producing the ionomer resin used in the present invention is already well known (Japanese Patent Publication No. 39-6810), and is produced by reacting a base copolymer with a metal compound capable of ionizing the copolymer. .

The base copolymer contains an α-olefin represented by the general formula RCH=CH3 (where R is selected from the group consisting of hydrogen and an alkyl group having 1 to 8 carbon atoms) and an α,β-ethylenically unsaturated group. and a carboxylic acid having 1 to 2 carboxyl groups, but α-olefin-
Monocarboxylic acid copolymers are particularly suitable.

Examples of base copolymers that can be suitably used include ethylene/acrylic acid copolymers, ethylene/methacrylic acid copolymers, ethylene/itaconic acid copolymers, ethylene/maleic acid copolymers, and ethylene/acrylic acid/acrylic acid copolymers. Methyl methacrylate copolymer, ethylene/methacrylic acid/vinyl acetate copolymer, ethylene/acrylic acid/vinyl alcohol copolymer, ethylene/propylene/acrylic acid copolymer, ethylene/styrene/acrylic acid copolymer, ethylene /methacrylic acid/acrylonitrile copolymer, ethylene/vinyl chloride/acrylic acid copolymer, ethylene/chlorotrifluoroethylene/methacrylic acid copolymer, polyethylene/acrylic acid graft copolymer, polypropylene/acrylic acid graft copolymer etc. can be mentioned.

In addition, when the base copolymer is an α-olefin-monocarboxylic acid copolymer, the metal ion has a valence of 1 to 3 (for example, Na+, Li+
Cu2+ Be2+2+ 2+ Mg, Zn, AII"+, etc.) are suitable, and in the case of α-olefin-dicarboxylic acid copolymers, monovalent atomic compounds (e.g. Na"K, LL, etc.) are suitable.
etc.) are suitable.

Examples of ionomer resins used include ethylene-
Acrylic acid copolymer and metal ions such as Na” and Zn2
An example is a combination with +.

The molecular weight of ionomer resin is 10.000 to 1.000
．． 0 (10, preferably 20,000 to 800,000
, more preferably in the range of 30,000 to 500,000.

The ionomer resin used in the present invention is sold under the trade name "Himilan" by DuPont Mitsui Polychemicals.

In the present invention, an inorganic hydrate is used in order to improve the flame retardance that is impaired by alloying with an elastomer. It is important that the inorganic hydrate used in the present invention contains water of crystallization, and any inorganic substance with any structure can be used as long as it contains water of crystallization.

Examples of the inorganic hydrate used in the present invention include magnesium hydroxide, aluminum hydroxide, calcium silicate hydrate, etc., but since melt-kneading is performed above the melting point of PPS, the decomposition temperature is 280 ° C. Above, preferably 3
The temperature is 00°C or higher, more preferably 320°C or higher.

Furthermore, compared to untreated materials, those surface-treated with higher fatty acids have better affinity with resins and better dispersibility, and are therefore preferably used.

Among the above-mentioned inorganic hydrates, magnesium hydroxide is preferably used because it has a high flame retardant effect and a low decrease in mechanical properties.

Among the above, magnesium hydroxide is available from Kyowa Kagaku ■ under the name ``Kisma'', aluminum hydroxide is available from Shin-Etsu Chemical under the name Hisilite H-42J, and calcium silicate hydrate is available under the name ``Dialyte-M''. Under the name of Kamishima Chemical Industry■
More commercially available.

In the present invention, the mixing ratio of modified PPS (A) and elastomer (B) is (A)/(B) = 5 by weight.
The range is from 0150 to 9515, and the modified P P S (
If the content of A) exceeds 95% by weight, the improvement effect of the modified PPS will be reduced, and if it is less than 50% by weight, the inherent properties of the modified PPS will be significantly lost, which is not preferable.

Among them, the preferred mixing ratio is (A)/(B) = 70/3
It is 0 to 90/10.

Further, in the present invention, an inorganic hydrate is added to the resin composition, and 1 to 150 parts by weight of the inorganic hydrate is added to the resin composition.
If it is less than 5 parts by weight, the flame retardant effect of the inorganic hydrate will be reduced, and if it exceeds 200 parts by weight, the mechanical properties of the resin composition will be impaired, which is not preferable. Among them, the preferred mixing ratio is (C)/+(A)/
(B) l = 10/100 to 60/100.

Further, the resin composition of the present invention can be improved in rigidity and the like by adding inorganic and organic fillers as necessary. Suitable fillers include glass fibers, carbon fibers, metal fibers, aramid fibers, potassium titanate, asbestos,
silicon carbide, ceramic, silicon nitride, barium sulfate,
Calcium sulfate, kaolin, clay, pyroferrite, bentonite, sericite, zeolite, mica, mica, nephelinsinite, talc, atalpulgite, wollastonite, PMF, ferrite, calcium silicate, calcium carbonate, magnesium carbonate, Mention may be made of reinforcing fillers such as dolomite, zinc oxide, titanium oxide, magnesium oxide, iron oxide, molybdenum disulfide, graphite, gypsum, glass beads, glass powder glass balloons, quartz, and quartz glass.

The resin composition of the present invention may also contain a plasticizer such as an aromatic hydroxy derivative, such as 2-ethylhexyl-p-hydroxybenzoate, a sulfonic acid amide, such as benzenesulfonamide, or a small amount of other mold release agent. Coupling agents, colorants, lubricants, heat stabilizers, weather stabilizers, foaming agents, rust preventives, etc. may be added.

Furthermore, in the present invention, a flame retardant aid such as antimony dioxide can be used to enhance the flame retardant effect.

The resin composition of the present invention can be prepared by various known methods. For example, there is a method in which the raw materials are uniformly mixed in advance in a mixer such as a tumbler or a Henschel mixer, then fed into a -screw or twin-screw extruder, melt-kneaded, and then prepared into pellets.

There are no particular limitations on the procedure for preparing the composition of the present invention, but PPS
A typical method is to melt-knead PPS and isocyanate, melt-knead the elastomer, melt-knead the flame retardant and reinforcing agent in an extruder at a temperature higher than the melting point of PPS, and then pelletize.

In addition, the melt-kneading temperature is preferably 280 to 320°C, and 280°C to 320°C.
If it is below 0°C, PPS may not be sufficiently melted.
If the temperature exceeds 320°C, the elastomer may undergo thermal deterioration or gelation, and the flame retardant may decompose, so care must be taken.

The evaluation of flame retardancy in the present invention was conducted according to the UL94 standard (1/16 inch thickness) by Underwriters Laboratories in the United States, and the tensile test, bending test, and Izot impact strength were evaluated according to ASTM D-838, respectively. A
It was conducted according to STM D-790 and D-258.

〔Example〕

The present invention will be explained in more detail with reference to Examples below.
This does not limit the invention.

Reference Example 1 (Production of modified pps) After drying PPS powder (Toprene T-4) at 150°C for 3 hours, the temperature was lowered to 50°C, and 4,4°-diphenylmethane diisocyanate was added to 2 parts by weight of ppstoo. Parts by weight were blended, mixed for 30 seconds in a Henschel mixer in a nitrogen atmosphere, and then pelletized in a nitrogen atmosphere at a cylinder temperature of 290 to 300°C using an Ikegai Tekko "PCM-30" twin screw extruder.

Comparative Example 1 580 parts by weight of the modified PP obtained in Reference Example 1, maleic anhydride-containing ethylene-acrylic ester copolymer (manufactured by Sumitomo CPF Chemical Co., Ltd., Bondine A X g390)
．． Acrylic acid ester content 32%, maleic anhydride content 1.75%, melt flow 1 flow mixture, cylinder temperature 240 ° C in the hopper part, 300 ° C in the central part,
The mixture was melt-kneaded using a co-rotating twin-screw extruder PCM-30 manufactured by Ikegai Tekko Co., Ltd. whose tip was set at 300° C., and pellets were obtained in a conventional manner.

43 parts by weight of glass fiber (manufactured by Nippon Electric Glass Co., Ltd., T-717P) was mixed with 100 parts by weight of this pellet, and a pellet was obtained using the same extruder at the same temperature setting. ℃, the tip part was set at 300°C, and the mold temperature was set at 140°C, and a test piece was obtained by a normal injection molding method, and various physical properties were measured. The obtained results are summarized in Tables 1 and 2.

Comparative Example 2 Physical property values were obtained in the same manner as in Comparative Example 1, except that unmodified PPS was used.

Example 1 134 parts by weight of the modified PPS obtained in Reference Example 1, maleic anhydride-containing ethylene-acrylic ester copolymer (manufactured by Sumitomo CPF Chemical Co., Ltd., Bondine A
5390, acrylic acid ester content 32%, maleic anhydride content 1.75%, manufactured by Meltflow G1F Chemical Co., Ltd.
Kisuma 5E) 25 parts by weight were mixed in a Henschel mixer, and the cylinder temperature was adjusted to 240°C in the hopper part.
The mixture was melt-kneaded using a co-rotating twin-screw extruder PCM-30 manufactured by Ikegai Tekko Co., Ltd., set at 300°C at the center and 300°C at the tip, and pellets were obtained in a conventional manner. This pellet 100
Glass fiber (manufactured by Nippon Electronics Glass Co., Ltd., T-717P) in the weight part
) 43 parts by weight were mixed and pellets were obtained using the same extruder at the same temperature settings, and the cylinder temperature was set at 240°C in the hopper, 290°C in the center, and 300°C in the tip, and the mold temperature was set at 140°C. Test pieces were obtained using the usual injection molding method and various physical properties were measured. The results obtained are shown in Table-1.

Examples 2 to 4 Pellets were obtained with each composition (as in Example 1, Bondine AX 8390 was used as the elastomer) in the same manner as in Example 1, and various physical properties were measured. The results are shown in Table-1゜2.

In the examples, there was no significant deterioration in physical properties as seen with the combination of ordinary flame retardants or inorganic fillers, and moreover, flame retardancy, which was not obtained in Comparative Example 1, was exhibited. Furthermore, Comparative Example 2 shows that modified PPS has much better impact resistance than unmodified PPS. This is likely due to the existence of some good interaction between the modified PPS and the flame retardant as used in the present invention.

〔Effect of the invention〕

The resin composition of the present invention is a resin in which each component is blended with good compatibility, has a good molded product appearance, has excellent impact strength, thermal shape stability, and mechanical properties, and has good flame retardancy. It is a highly practical molding material with excellent physical properties as an engineering plastic.

(Margin below)

Claims (1)

[Claims] (1) A modified polyphenylene sulfide resin (A) obtained by melt-kneading a polyphenylene sulfide resin and a non-blocked polyfunctional isocyanate compound, and ethylene 50
~90% by weight, 5-49% by weight of α,β-unsaturated carboxylic acid alkyl ester, and 0.5-10% by weight of maleic anhydride.
At least one elastomer (B) selected from ethylene copolymers, epoxy group-containing olefin copolymers, and ionomer resins consisting of % by weight and an inorganic hydrate (C)
and (A)/(B)=50/50 to 95/5, and (C)
A resin composition characterized in that it is blended in a weight ratio of /{(A)+(B)}=5/100 to 150/100.