JP3287109B2 - Method for molding polyarylene sulfide resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for molding a polyarylene sulfide (PAS) resin composition using a low-temperature mold.

[0002]

2. Description of the Related Art In recent years, as the demand for higher performance of plastic materials has increased, PAS with excellent heat resistance, mechanical properties, and chemical resistance has attracted attention.
Applications are expanding to electronic components and the like.

[0003] PAS is a crystalline engineering plastic, but because of its low crystallization rate, in order to obtain a resin having sufficient mechanical strength for practical use in injection molding, a high mold temperature of around 130 ° C. is required. Cooling time was required. This is a serious problem in expanding the use of PAS, and it is desired that a general-purpose resin molding machine can be molded in a short time at a mold temperature of 100 ° C. or less, which is a processing condition.

[0004] In order to solve this problem, for example, a fatty acid ester (Japanese Patent Application Laid-Open No. H4-154867) or an aromatic sulfonamide (Japanese Patent Application Laid-Open No. H5-59279) is added to improve the releasability from a mold. And a method of accelerating crystallization by adding a modified polyalkylene glycol (JP-A-3-250049) or an organic metal phosphate salt (JP-A-2-142854).

However, in these methods, even if the desired effects cannot be obtained or the releasability or appearance is improved due to insufficient heat resistance of the resin composition, the mechanical strength and heat resistance are reduced. There are problems such as damage.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide a novel and useful molding method of a polyarylene sulfide resin composition which can be used even at a low temperature without impairing the original mechanical properties and heat resistance of the polyarylene sulfide. With the goal.

[0007]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to achieve the above object, and as a result, using a polyarylene sulfide resin composition containing a specific imide compound, the mold temperature has been reduced. It has been found that a molded product having the original mechanical strength and heat resistance of polyarylene sulfide can be obtained even at 100 ° C. or lower, and the present invention has been completed based on such findings.

That is, the method for molding a polyarylene sulfide resin composition according to the present invention is characterized in that a bisimide represented by the general formula (1), a general formula (4) or a general formula (4) is used for 100 parts by weight of the polyarylene sulfide resin. 1) selected from the group consisting of monoimides represented by 5) and metal salts thereof
It is characterized by injection-molding a resin composition containing 0.1 to 100 parts by weight of one or more kinds of imide compounds (hereinafter referred to as “the present imide compound”).

[0009]

Embedded image [Wherein, R ¹ and R ² are the same or different and each have 4 to 22 carbon atoms.
Or a cycloalkyl group having 4 to 6 carbon atoms, or a group represented by the general formula (2) or (3). A ¹ and A ² are the same or different and represent a single bond or a phenylene group. ]

[0010]

Embedded image [Wherein, R ³ represents an alkyl group having 1 to 22 carbon atoms. R ⁴
Represents a single bond or an alkylene group having 1 to 2 carbon atoms. a represents an integer of 1 to 2. ]

[0011]

Embedded image [In the formula, R ⁵ represents an alkyl group having 1 to 22 carbon atoms. R ⁶
Represents a single bond or an alkylene group having 1 to 2 carbon atoms. b represents an integer of 0 to 2. ]

[0012]

Embedded image [Y when in the formula, X is NH-A ⁴ -R ⁸ represents a hydroxyl group,
Y is X when the NH-A ⁴ -R ⁸ represents a hydroxyl group. R ⁷ , R ⁸
Has the same meaning as R ¹ in formula (1), and may be the same or different. A ³ and A ⁴ are the same or different and represent a single bond or a phenylene group. ]

[0013]

Embedded image [Wherein R ⁹ and R ¹⁰ are the same or different and each have 4 to 2 carbon atoms.
2 represents an alkyl group or an alkenyl group. A ⁵ and A ⁶ are the same or different and represent a single bond or a phenylene group. ]

The imide compound is, for example, 1,2,3,
4-butanetetracarboxylic acid (hereinafter abbreviated as “BTC”) or its monoanhydride or dianhydride (hereinafter “BTC”)
Class C ". ) And an aliphatic primary amine, an alicyclic primary amine or an aromatic primary amine having a predetermined structure by dehydration condensation or by a decarboxylation reaction of the amine with an isocyanate derivative.

The dehydration reaction is most preferably industrially performed by heating, but if necessary, a dehydrating reagent such as acetic anhydride-pyridine or carbodiimide may be used.

Examples of the aliphatic primary amine include saturated and unsaturated linear and branched aliphatic amines.
This may have an aromatic ring.

Examples of the aliphatic amine include butylamine, pentylamine, hexylamine, heptylamine, octylamine, 2-ethylhexylamine, nonylamine, decylamine, undecylamine, dodecylamine, tridecylamine, tetradecylamine, and pentadecyl. Amines, hexadecylamine, heptadecylamine, octadecylamine, octadecenylamine, nonadecylamine, eicosylamine, henekoisylamine, docosylamine, benzylamine, etc., among which decylamine, dodecylamine, tetradecylamine, hexadecylamine , Octadecylamine is recommended.

Furthermore, it is substantially impossible to use a mixture containing these amines, that is, natural amines such as cocoamine, tallowamine, fish oil amine, hydrogenated cocoamine, hydrogenated tallowamine, and hydrogenated fish oil amine. Economically meaningful.

Specific examples of the alicyclic primary amine include cyclobutylamine, cyclopentylamine, cyclohexylamine, cyclohexylmethylamine, cyclohexylethylamine, methylcyclohexylamine, and dimethimecyclohexylamine.

Specific examples of the aromatic primary amine include allylaniline, butylaniline, pentylaniline, hexylaniline, heptylaniline, octylaniline, nonylaniline, decylaniline, undecylaniline, dodecylaniline, tridecylaniline, and tetradecylaniline. Decyl aniline, pentadecyl aniline, hexadecyl aniline, heptadecyl aniline, octadecyl aniline, nonadecyl aniline, eicosyl aniline, heneikosyl aniline, docosyl aniline and the like, among which decyl aniline, dodecyl aniline, tetradecyl aniline, Hexadecylaniline and octadecylaniline are recommended.

The imide compound is converted into a partial ester or a whole ester intermediately with BTCs and a lower alcohol (methyl alcohol, butyl alcohol, etc.), or is converted into an acid chloride with a chlorinating reagent such as thionyl chloride, phosgene or chlorine. And the like, and the above-mentioned amine is allowed to act in a substantially dehydrated form of BTC.

Among the imide compounds of the present invention, imide compounds containing a carboxyl group have an increased affinity with a mold and an increased external lubricity. Specifically, a carboxyl group formed by an amide acid between BTCs and an aliphatic amine is effective. For this reason, the dehydration reaction of the BTCs and the aliphatic amine may be suppressed as necessary to leave a carboxyl group.
The remaining carboxyl group may be used as it is, or may be in the form of a metal soap such as sodium, potassium, calcium, magnesium, barium, zinc, and aluminum. An excess of aliphatic amine can be added to dehydrate amidate to block carboxyl groups.

In using the imide compound, the chain length of the alkyl group or alkenyl group is appropriately selected according to the desired effect. That is, generally, the carbon number is 4-1
The imide compound having the group having a chain length of 8 is often effective for lowering the melt viscosity and promoting nucleation, and has 1 carbon atom.
The imide compounds of Nos. 8 to 28 often function as an external lubricant.

These imide compounds may be used alone or in combination as appropriate, depending on desired physical properties. In some cases, it may be added in the form of a mixed imide compound.

The PAS used in the present invention is mainly (-
A polymer containing at least 70 mol%, more preferably at least 90 mol% of a repeating unit represented by Ph-S-),
Particularly, polyphenylene sulfide (PPS) is preferably used.

The PPS is not particularly limited as long as it is produced by a generally known method. For example, a relatively low-molecular-weight polymer disclosed in Japanese Patent Application Laid-Open No. 45-3368 can be used under the oxygen atmosphere. And a polymer having a high molecular weight by heating or crosslinking with a peroxide.
An essentially linear, relatively high molecular weight polymer obtained by the method of Example 40 can be used.

Furthermore, 30 mol% or less as a copolymer component,
If it is preferably at most 10 mol%, a copolymer with another repeating unit can be used.

Examples of the other repeating units include orthophenylene sulfide, metaphenylene sulfide, diphenyl sulfide ether, diphenyl sulfide sulfone, diphenylene sulfide ketone, biphenylene sulfide, naphthalene sulfide, diphenylene sulfide methane, diphenylene sulfide propane And trifunctional phenylene sulfide and substituted phenylene sulfide (substituents such as an alkyl group, a nitro group, a phenyl group, a carboxylic acid group, and an alkoxy group amino group).

The melt viscosity of PPS is not particularly limited as long as injection molding is possible.
00000 poise (300 ° C., shear rate 10 ³ / sec),
Preferably, it is about 100 to 50,000 poise.

The compounding amount of the imide compound to PAS is 0.1 to 100 parts by weight, preferably 0.5 to 50 parts by weight, based on 100 parts by weight of PAS. Further, when used as a low-viscosity agent or a crystallization accelerator, it is desirable to add it in an amount of 1 to 20 parts by weight. If the amount is less than 0.1 part by weight, the properties are not so improved. If the amount is more than 100 parts by weight, the heat resistance required for the resin may be impaired.

The resin composition used in the present invention may contain a nucleating agent, a reinforcing agent, a filler, an antioxidant, an ultraviolet absorber, an antistatic agent, a flame retardant, a modifier, A lubricant and the like can be blended.

When a crystal nucleating agent is used in combination, the crystallization rate is further increased, so that a favorable result is often obtained. As such a crystal nucleating agent, a known inorganic or organic nucleating agent can be used.

Examples of the inorganic nucleating agent include talc, mica, silica, kaolin, clay, attapullite, romite powder, quartz powder, zinc white, diatomaceous earth, montmorillonite,
Permiculite, amorphous silica, glass powder, silica-alumina, wollastonite, hytron, boron,
Nitrite, carbon black, pyroferrite, graphite, zinc sulfide, boron nitride, silicon resin powder, silicates such as calcium, magnesium, aluminum, lithium, barium, titanium, etc., sulfates, carbonates, phosphates, aluminates , Oxides and the like.

The organic nucleating agents include metal salts of aliphatic carboxylic acids, metal salts of aromatic carboxylic acids such as benzoic acid and terephthalic acid, aromatic phosphonic acids and metal salts, metal salts of aromatic phosphates, benzenesulfonic acid, Crystallinity of metal salts of aromatic sulfonic acids such as naphthalene sulfonic acid, metal salts of β-diketones, high molecular compounds having a metal salt of carboxyl group, parahydroxybenzoic acid ester, 4,6 nylon, polyphenylene sulfide ketone, etc. Examples thereof include polymer fine powder.

Further, a filler may be added as a reinforcing agent or for increasing the volume.

The filler is not particularly limited, and fillers for reinforcing carbon black, calcium carbonate, magnesium carbonate, barium sulfate, kaolin, calcined clay, talc, aluminum silicate, calcium silicate, silica Acid, carbon fiber, glass fiber, asbestos fiber, carbon fiber, silica fiber, zirconia fiber,
Examples thereof include aramid fibers, potassium titanate fibers, and metal fibers.

In using these fillers, it is desirable to use a surface treating agent and a sizing agent if necessary. As such a surface treatment agent and a sizing agent, a silane-based compound, an epoxy-based compound, an isocyanate-based compound, and the like are used.

In addition, additives such as antioxidants such as hindered amine compounds, benzophenone compounds and benzotriazole compounds and additives such as pigments, dyes, antistatic agents, lubricants and mold release agents can be optionally contained.

Further, as long as the object of the present invention is not impaired,
Other thermoplastic resins, for example, polyethylene, polypropylene, polybutene, polystyrene, polyphenylene ether, polyether sulfone, polyether ether ketone, polyphenylene oxide, polyoxymethylene,
PTFE, maleimide-modified ABS, chlorinated PVC, aromatic polyamide such as terephthalic acid and aliphatic diamine or xylylenediamine and aliphatic dicarboxylic acid, 6 nylon, 6,6 nylon, 4,6 nylon, 11 nylon,
It is also possible to add aliphatic polyamide such as 12 nylon, polycarbonate, polyethylene terephthalate, polybutylene terephthalate, polyarylate, liquid crystal polymer, polyamide imide, polyether imide, polyimide and the like.

The method for preparing the PAS resin composition according to the present invention can be carried out by a known method. For example, a method in which the present imide compound is directly added to a PAS resin powder, a method in which the imide compound is dissolved in xylene or dimethylformamide and the like is mixed with the PAS resin powder, and then dried, a method in which the slurry is added to a slurry after polymerization of PAS, a method such as glass fiber, etc. With a reinforcing agent, a filler such as calcium carbonate, and other various additives used as necessary, the mixture is uniformly mixed with a V-blender, a ribbon blender, a Henschel mixer, a tumbler blender, and the like, and a Banbury mixer, a kneader, an oven roll, There is a method of heating, melting and kneading with a screw extruder, a twin screw extruder, a single screw reciprocating screw or the like to form pellets, and a method of melting and kneading to form pellets is recommended. At this time, there is also a method of kneading only necessary components to form a master batch.

The kneading temperature is equal to or higher than the melting point of the target PAS resin.
It is preferable to carry out at 400 ° C., and if it is 280 ° C. or less, the dissolution of the resin becomes insufficient.

A method for obtaining a molded article from the resin composition obtained by the above method can be performed by a known method.

The injection molding machine is a screw in-line type,
Any plunger type is possible, and it is preferable that the capacity of the molding machine coincides with the injection amount in order to avoid extra heat history. The screw is preferably a wear-resistant material.

The resin pellets to be molded are from 120 to 1
Pre-drying at 60 ° C. for 2 to 6 hours is desirable, and appearance defects such as silver streaks and fogging are less likely to occur.

The resin temperature during injection molding is 280 to 40
0 ° C, particularly preferably about 290-360 ° C.

The mold temperature is, for example, 0 to 100 ° C., and particularly, 40 to 80 ° C. is recommended. However, injection molding can be performed at a mold temperature of 100 ° C. or more. When importance is placed on the heat resistance of the molded product, a higher mold temperature is obtained, and when importance is placed on the dimensional accuracy, a lower mold temperature is preferable.

The injection pressure is preferably 500 to 1300 kg / cm ² , and a high-pressure and high-speed molding makes it easy to obtain a uniform and glossy molded product, and a low-pressure and low-speed molding reduces warpage and burrs. Products are easy to obtain.

The rotation speed of the screw is about 10 to 300 rotations, preferably about 40 to 200 rotations.

When it is desired to increase the molding cycle, it is preferable to increase the rotation speed. However, it is not preferable to increase the rotation speed more than necessary because the glass fiber is cut or the resin generates heat.

The PAS resin composition according to the present invention has a high crystallization rate and can be molded at a wide range of mold temperatures from low to high, and the resulting molded article has good appearance and less burrs. Since the dimensional shrinkage is small and the mechanical strength is excellent, materials for various molded products, for example, electrical and electronic equipment parts,
Suitable for automotive equipment parts and chemical parts materials.

[0051]

The present invention will be described in detail with reference to the following examples. The mechanical properties of the PPS resin composition were evaluated by the following methods.

A predetermined resin composition component was preliminarily mixed with a Henschel mixer, and a composition obtained by mixing 65 parts by weight of a commercially available glass fiber was melt-kneaded with an extruder having a cylinder temperature of 310 ° C. to obtain a PPS resin composition. Obtain a pellet of the product.
Next, injection molding is performed at a cylinder temperature of 310 ° C. and a mold temperature of 70 ° C. The tensile strength, bending strength and Izod impact strength of the test piece thus obtained are measured by the following methods.

The tensile strength conforms to ASTM-D68.

The bending strength of the molded article conforms to ASTM-D790.

Izod impact strength of molded article According to ASTM-D256.

Production Example 1 650 g of sodium sulfide 2.9 hydrate was placed in an autoclave.
(5.0 mol) and N-methylpyrrolidone (NMP) 18
And then heated to 205 ° C. and distilled water
g was removed. Next, 720 g of p-dichlorobenzene
(4.85 mol) and 400 g of NMP and 250 ° C.
For 4 hours. After completion of the reaction, the mixture was cooled to room temperature, the product was separated by filtration, and washing with warm water was repeated.
Drying at ℃ for 24 hours gave a PPS resin (PPS-1) having a melt viscosity of 300 poise.

Production Example 2 PPS-1 was thermally crosslinked by treating it in air at 260 ° C. for 5 hours to give a PPS having a melt viscosity of 2500 poise.
A resin (PPS-2) was obtained.

Production Example 3 Sodium sulfide / 2.9 hydrate 650 was placed in an autoclave.
g (5.0 mol), 210 g (5.0 mol) of lithium chloride and 1800 g of NMP were charged, the temperature was raised to 205 ° C., and about 140 g of distilled water was removed. Next, 720 g (4.85 mol) of p-dichlorobenzene and 400 g of NMP were used.
Was added and reacted at 250 ° C. for 4 hours. After completion of the reaction, the reaction mixture was cooled to room temperature, the product was separated by filtration, washed repeatedly with warm water, dried at 100 ° C. for one day and night, and had a melt viscosity of 1800.
Poise PPS resin (PPS-3) was obtained.

Production Example 4 19.8 g (0.1 mol) of BTC dianhydride and 53.8 g (0.2 mol) of tallowamine were mixed and stirred in xylene and heated. The xylene was also removed while separating and removing the generated water, and the mixture was heated until the temperature finally reached 260 ° C., and the reaction was continued until the generated water reached 3.6 g. After completion of the reaction, the mixture was neutralized with an aqueous solution of potassium hydroxide, treated with clay, filtered, and the remaining xylene was topped to prepare an imide compound (imide A).

Production Example 5 Using 19.8 g (0.1 mol) of BTC dianhydride, 34.0 g (0.2 mol) of laurylamine and xylene, 3.0 g of produced water was distilled off to terminate the reaction. did. After completion of the reaction, a monoimide compound in which a carboxyl group remains partially by topping xylene as it is (this imide B)
It was created.

Production Example 6 23.4 g (0.1 mol) of BTC and laurylamine 3
Using 4.0 g (0.2 mol) and xylene, 5.4 g of produced water was distilled off to complete the reaction. After the completion of the reaction, the mixture is neutralized with sodium hydroxide, and topped with xylene as it is to obtain an imide compound containing a carboxylate (the present imide C)
It was created.

Production Example 7 Using 23.4 g (0.1 mol) of BTC, 52.2 g (0.2 mol) of paradodecylaniline and xylene, 7.2 g of produced water was distilled off to terminate the reaction. After the reaction,
The mixture was neutralized with calcium hydroxide and topped with xylene as it was to prepare a diimide compound (the present imide D).

Examples 1 to 5 A predetermined PPS resin, the present imide compound and, if necessary, talc were blended to prepare a PPS resin composition, and the molded product was measured for tensile strength, bending strength and Izod impact strength. did. Table 1 shows the obtained results.

Comparative Example 1 The molded product of “PPS-1” itself was measured for tensile strength, bending strength and Izod impact strength. Table 1 shows the obtained results.

Comparative Example 2 PPS was carried out in the same manner as in Example 2 except that ethylene bisstearamide (EBS) was used in place of “the present imide B”.
A resin composition was prepared, and the tensile strength, bending strength and Izod impact strength of the molded product were measured. Table 1 shows the obtained results.

Comparative Example 3 A PPS resin composition was prepared in the same manner as in Example 3 except that "the present imide A" was not used, and the tensile strength, bending strength and Izod impact strength of the molded product were measured. Table 1 shows the obtained results.

[0067]

By applying the method according to the present invention, molding can be carried out even at a low temperature without impairing the mechanical properties and heat resistance inherent in polyarylene sulfide.

[Table 1]

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B29C 45/00-45/73 B29K 81:00

Claims (3)

(57) [Claims] 1. A group consisting of a bisimide represented by the general formula (1), a monoimide represented by the general formula (4) or (5) and a metal salt thereof based on 100 parts by weight of the polyarylene sulfide resin. A method for molding a polyarylene sulfide resin composition, comprising injection molding a resin composition containing 0.1 to 100 parts by weight of one or more imide compounds selected from the group consisting of: Embedded image [Wherein, R ¹ and R ² are the same or different and each have 4 to 22 carbon atoms.
Or a cycloalkyl group having 4 to 6 carbon atoms, or a group represented by the general formula (2) or (3). A ¹ and A ² are the same or different and represent a single bond or a phenylene group. ] [Wherein, R ³ represents an alkyl group having 1 to 22 carbon atoms. R ⁴
Represents a single bond or an alkylene group having 1 to 2 carbon atoms. a represents an integer of 1 to 2. ] [In the formula, R ⁵ represents an alkyl group having 1 to 22 carbon atoms. R ⁶
Represents a single bond or an alkylene group having 1 to 2 carbon atoms. b represents an integer of 0 to 2. ] [Y when in the formula, X is NH-A ⁴ -R ⁸ represents a hydroxyl group,
Y is X when the NH-A ⁴ -R ⁸ represents a hydroxyl group. R ⁷ , R ⁸
Has the same meaning as R ¹ in formula (1), and may be the same or different. A ³ and A ⁴ are the same or different and represent a single bond or a phenylene group. ] [Wherein, R ⁹ and R ¹⁰ are the same or different and each have 4 to 2 carbon atoms.
2 represents an alkyl group or an alkenyl group. A ⁵ and A ⁶ are the same or different and represent a single bond or a phenylene group. ] 2. The method for molding a polyarylene sulfide resin composition according to claim 1, wherein the mold temperature is 0 to 100 ° C. 3. The method for molding a polyarylene sulfide resin composition according to claim 1, wherein the polyarylene sulfide resin composition is a polyphenylene sulfide resin composition.