JPH0822962B2 - Polyphenylene sulfide resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to polyphenylene sulfide (hereinafter referred to as "PP
"S". ) A resin composition, more specifically, a composition comprising a blend of a polyphenylene sulfide resin, which is useful as a film, a fiber, a composite material, an extruded product and the like having excellent heat resistance.

[Conventional technology]

Poly-p-phenylene sulfide has characteristics such as excellent heat resistance, mechanical strength, chemical resistance, dimensional stability, and flame retardancy. For this reason, poly-p-phenylene sulfide is used for injection molding and is used as automobile parts, electric / electronic parts, and mechanical parts. However, poly-p
-Phenylene sulfide has a too high crystallization rate and tends to form coarse spherulites, so that it is difficult to form fibers, films, and other extrusion-molded products by the melt extrusion method.

Several methods have been proposed to remedy these drawbacks. For example, a method in which the chlorine content in the polymer is 0.3% by weight or more and the crystallization peak temperature is 200 ° C. or less (JP-A-59-453230) and a method of forming a p-phenylene sulfide block copolymer (JP-A-61-14228). issue),
And a method of producing a p-phenylene sulfide / m-phenylene sulfide random copolymer (US Pat. No. 3,863).
No. 9,434). However, these methods have a problem that the reaction is performed in two steps during the synthesis reaction of the polymer or the reaction takes a long time. Further, p-phenylene sulfide / m-phenylene sulfide random copolymer is substantially amorphous, but its melting point (Tm) is extremely low, and therefore it is not satisfactory in heat resistance.

[Problems to be solved by the invention]

The object of the present invention is to have a low crystallization temperature (Tc) while maintaining a high melting point (Tm) (that is, high heat resistance) without using complicated means as described above, and to obtain a film, a fiber Another object of the present invention is to provide a PPS resin composition useful as various extruded products by the melt extrusion method.

[Means for solving problems]

The above-mentioned object is to add an aromatic sulfonic acid alkali salt represented by the following formula when a polyphenylene sulfide homopolymer is produced by reacting an alkali metal sulfide with a dihaloaromatic compound in an organic amide melt. Poly-p-phenylene sulfide homopolymer 90 produced by
~ 98% and 2-10% by weight of poly-m-phenylene sulfide homopolymer prepared in the same manner.

Although m-PPS has a low crystallization temperature (Tc) and is substantially amorphous, it has a remarkably low melting point (Tm) and is impractical. In contrast, the PPS resin composition of the present invention, which is a blend of p-PPS and a small amount of m-PPS, surprisingly has a low crystallization temperature (while maintaining a high level of heat resistance). Tc).

P-PPS, which is a constituent component of the PPS resin composition of the present invention, is
It is obtained by reacting an aromatic p-dihalogen compound with an alkali metal sulfide, or hydrogen sulfide with an alkali metal salt or an alkali hydrosulfide with an alkali metal base in the presence of an amide polar solvent and an aromatic sulfonic acid alkali salt. A typical reaction formula is as follows.

The p-PPS used in the present invention is The polymer may contain a co-condensation unit such as Ether units, such as Like sulfon unit, A ketone unit such as Furthermore, p-PPS
May be partially crosslinked by heat treatment or chemical treatment in air.

M-PPS which is another constituent of the PPS resin composition of the present invention
Is an aromatic m-dihalogen compound and an alkali metal sulfide,
Alternatively, it can be obtained by reacting hydrogen sulfide with an alkali metal salt or an alkali hydrosulfide with an alkali metal base in the presence of an amide polar solvent and an aromatic sulfonic acid alkali salt. A typical reaction formula is as follows.

m-PPS, like p-PPS, The polymer may contain a co-condensation unit such as, and the polymer may have a small amount of branching. An ether unit, such as Sulfon units such as A ketone unit such as Further, m-PPS may be partially crosslinked by heat treatment in air or chemical treatment.

As the aromatic p-dihalogen compound and aromatic m-dihalogen compound used in the above-mentioned synthesis of p-PPS and m-PPS, p-dichlorobenzene and m-dichlorobenzene are preferable, and they are also used for sulfidation. As the sulfur source, a combination of sodium hydrosulfide and sodium hydroxide, a combination of sodium sulfide, a combination of hydrogen sulfide and sodium hydroxide and the like are preferable. These alkali sulfides and alkali hydrosulfides may be used in the form of hydrates.

Examples of the amide-based polar melt used in the synthesis of p-PPS and m-PPS include hexamethylphosphoramide, dimethylsulfoxide, dimethylacetamide, N-alkyllactam, N, N-dialkylimidazolidinone, etc. And an organic solvent having an amide bond. Among these, N-alkyl lactams are preferable, and among them, N-alkyl lactams are preferable.
-Methylpyrrolidone is preferred.

As described in JP-A-55-43139, a polyphenylene sulfide having a high degree of polymerization can be easily obtained by allowing an aromatic sulfonic acid alkali salt represented by the following formula to coexist in an organic amide solvent. .

In the above formula, R represents an alkyl group having 1 to 12 carbon atoms, n represents an integer of 0, 1 or 2, and M represents an alkali metal selected from sodium, potassium, rubidium and cesium. Specific examples of the aromatic sulfonic acid alkali metal salt include p-toluenesulfonic acid, benzenesulfonic acid, 2,4-ditylbenzenesulfonic acid, 2,5-dimethylbenzenesulfonic acid, p-ethylbenzenesulfonic acid and dodecylbenzenesulfone. Examples thereof include alkali metal salts such as acids, and the use amount thereof is preferably in the range of 0.1 to 1.5 mol based on the alkali metal sulfide. The synthesis of p-PPS and m-PPS is a known method,
For example, it can be performed by the method as disclosed in US Pat. No. 3,354,129. That is, it is necessary to previously mix the above-mentioned sulfur source and reaction solvent and dehydrate the mixture to reduce the water content to a predetermined value or less. As a dehydration method, a method of heating the mixture to near the boiling point of the solvent and distilling it is generally used. It is dehydrated until the amount of water in the system during the reaction becomes about 3% by weight or less. The dehydrated system is once cooled to 170 ° C. or lower, and then an amide-based polar solvent solution of an aromatic dihalogen compound is added. That is,
Preferably, a solution of p-dichlorobenzene or m-dichlorobenzene in N-methylpyrrolidone is added. Then, the condensation reaction is performed under pressure. The condensation reaction takes place at a system temperature of 21
It is carried out at 0 to 270 ° C. for 0.5 to 10 hours under the condition of system pressure of 6 to 15 kg / cm ² . The condensation reaction may be a catalyst-free system, but in order to obtain a high-molecular weight polymer, it is used as a co-catalyst for organic acid alkali metal salts such as lithium acetate and sodium acetate disclosed in JP-B-52-12240. Preferably. A method in which an inorganic salt such as lithium carbonate or calcium hydroxide coexists is also used. The polymerized product can be obtained as an off-white powder or a granular product by neutralizing, filtering, washing and drying, if necessary, by a conventional method. Since m-PPS has a remarkably low melting point (Tm), separation from the polymerization solvent, purification and other operations are carried out at 100 ° C or lower, preferably 50 ° C or lower.

The degree of polymerization of p-PPS and m-PPS is not particularly limited, but those in the range of 100 to 3000 are generally used.

The blend ratio of p-PPS and m-PPS is 90-98% by weight of the former.
And the latter is 10 to 2% by weight. When the amount of m-PPS is less than 2% by weight, the crystallization temperature (Tc) of the PPS resin composition is high and the melt extrusion moldability is poor. On the contrary, the amount of m-PPS is 10
If the content exceeds 10% by weight, the melting point (Tm) will be considerably low and the molded product will have poor heat resistance.

The blended resin composition of p-PPS and m-PPS of the present invention is
It can be easily obtained by pre-mixing with a powder mixer such as a Henschel mixer or Nauter mixer, and melt-blending using an extruder maintained at a predetermined temperature condition. The temperature condition to be used for blending in an extruder is appropriately in the range from the melting point (Tm) of m-PPS to 400 ° C, and if it exceeds 400 ° C, the polymer is decomposed, which is not preferable. A more preferable temperature is 290 to 350 ° C. The mixing time may be relatively short, for example 3-5 at 300 ° C.
Minutes is fine.

In the PPS resin composition of the present invention, talc, silica, an inorganic filler such as calcium carbonate, a pigment such as titanium oxide, a reinforcing material such as glass fiber, carbon fiber, and aramid fiber are blended depending on the application. be able to. Also, polycarbonate, polyphenylene oxide, polysulfone, polyacrylate, polyacetal, polyimide,
It is also possible to mix and use one or more synthetic resins such as polyamide, polyester, polystyrene and ABS.

〔The invention's effect〕

The crystallization temperature (Tc) and melting point (Tm) of the PPS resin composition of the present invention are Tc of p-PPS and Tm of m-PPS.
It is located between Tc and Tm, but its Tc is generally p-
It is quite separated from that of PPS, and Tm is close to that of p-PPS. That is, the PPS resin composition of the present invention has heat resistance close to that of p-PPS and has a low crystallization temperature. Therefore,
In contrast to p-PPS resin, it can be melt extruded into fibers, films, and other extrudates.

〔Example〕

Hereinafter, synthetic examples of polymers used for preparing the PPS resin composition of the present invention, and examples and comparative examples of the composition will be described.

Synthesis Example 1 (Synthesis of m-PPS) 60% sodium sulfide 91.0 g, N-methyl 2-2 pyrrolidone (NMP) 280 was added to the stainless steel autoclave of 1.
g, 48% caustic soda, 2.03 g, sodium paratoluenesulfonate dihydrate 80.5 g, stirred under a nitrogen purge, heated and dehydrated to 204 ° C., and NMP73.7 g containing 35.3 g of water
Distilled. Cool to 150 ℃, and use m-dichlorobenzene 1
A solution obtained by dissolving 02.9 g in 100 g of NMP was added, the system was closed, and the pressure was raised to 3.0 kg / cm ^{2 with} nitrogen. The temperature is raised under stirring to 230 ° C.
For 2 hours and then at 260 ° C. for 3 hours. After cooling to room temperature, it was filtered using a Nuttier filter. Then, the salt-containing polymer was treated with 300 g of warm water at 50 ° C. five times,
Then, it was washed twice with 300 g of methanol and dried to obtain 68.8 g of white granular polymer (m-PPS-1).

Synthesis Example 2 (Synthesis of branched m-PPS) Synthesis Example 1 except that 102.39 g of m-dichlorobenzene and 0.64 g of 1,2,4-trichlorobenzene were used instead of 102.9 g of m-dichlorobenzene. M-PPS was synthesized under the same conditions, and white granular polymer (branched m-PPS: m-PPS-
2) 68g was obtained.

Synthesis Example 3 (Synthesis of p-PPS) PP was prepared under the same conditions as in Synthesis Example 1 except that 102.9 g of p-dichlorobenzene was used instead of 102.9 g of m-dichlorobenzene.
S is synthesized and white granular polymer (p-PPS-1) 71.8
got g.

Synthesis Examples 4 to 6 (Synthesis of m-phenylene sulfide / p-phenylene sulfide random copolymer) Instead of 102.9 g of m-dichlorobenzene, 5.15 g of m-dichlorobenzene and 97.75 g of p-dichlorobenzene (Synthesis Example 4) ), 12.35 g of m-dichlorobenzene and 90.55 g of p-dichlorobenzene (Synthesis example 5) and m-dichlorobenzene 2
PPS was synthesized under the same conditions except that 5.73 g and 77.18 g of p-dichlorobenzene (Synthesis Example 6) were used to obtain white granular polymers (R-PPS-1 to R-PPS-3).

The characteristic values of the polymer obtained in each of the above synthesis examples are as shown in Table 1.

Examples and Comparative Examples The polymers obtained in Synthesis Examples 1 to 5 were premixed in the form of powder having the composition shown in Table 2 and then premixed in a mold to obtain 10 mmφ × 15 mm ^H.
The above tablets were pressure-molded, and were melt mixed under the conditions of a temperature of 310 ° C. and a preheating time of 6 minutes using a flow tester equipped with a 0.5 mmφ × 1.0 mm ^L die. After extrusion, dry ice /
It was put into methanol and quenched.

With respect to each PPS resin composition sample, the crystallization temperature at rising temperature Tc ₁ , the crystallization temperature at falling temperature Tc ₂ and the peak temperature Tm of the melting point were measured by the same measurement method as described above. The results are shown in Table-3.

Example 4 (Production of film and physical property test) Using each sample of Synthesis Examples 1 to 3 and Comparative Examples 1 to 2, a press sheet and a biaxially stretched film were produced by the following treatment, and the strength was measured.

(A) After being heated to 310 ° C. and pressed to form a sheet, the sheet was put into cold water and rapidly cooled to produce a press sheet having a thickness of 0.1 to 0.2 mm.

(B) Using a small biaxial stretching machine, simultaneous biaxial stretching is performed on the press sheet of (a) at a stretching ratio of 3.0 × 3.0,
A stretched film was obtained. The stretching temperature was 95 ° C. Next, this stretched film was heat-treated at 250 ° C. for 10 seconds.

(C) Film-forming properties and film physical properties are shown in Table 4.

Claims (4)

[Claims] 1. When an alkali metal sulfide and a dihaloaromatic compound are reacted in an organic amide solvent to produce a polyphenylene sulfide homopolymer, an aromatic sulfonic acid alkali salt represented by the following formula is further added. Produced poly-p-phenylene sulfide homopolymer 90-98
%, And 2 to 10% by weight of the poly-m-phenylene sulfide homopolymer produced in the same manner as described above, a polyphenylene sulfide resin composition. (In the above formula, R is an alkyl group having 1 to 12 carbons, n is 0,
Representing an integer of 1 or 2, M represents an alkali metal selected from sodium, potassium, rubidium and cesium. ) 2. The composition according to claim 1, wherein the aromatic sulfonic acid alkali salt is sodium paratoluene sulfonate. 3. Poly-p at a temperature between the melting point (Tm) of poly-m-phenylene sulfide homopolymer and 400 ° C.
A composition according to claim 1 or 2 which is prepared by melt mixing a phenyle sulfide homopolymer and a poly-m-phenylene sulfide homopolymer. 4. A poly-p-phenylene sulfide homopolymer and a poly-m-phenylene sulfide homopolymer, a branched polymer or a partially cross-linked polymer. The composition according to any of the above.