JPH03197562A - Polyphenylene sulfide resin composition - Google Patents

Abstract

PURPOSE:To prepare the title compsn. giving a molded article with the flash generation reduced and excellent mechanical strengths by compounding a linear polyphenylene sulfide resin with a crosslinked polyphenylene sulfide resin and a silane compd. CONSTITUTION:The title compsn. is prepd. by compounding: 100 pts.wt. polyphenylene sulfide resin which is virtually linear and has a number-average mol.wt. (Mn) (measured by gel permeation chromatography using 1- chloronaphthalene as the solvent) of 7000 of higher and such a mol.wt. distribution that the ratio of the wt. average mol.wt. (Mw) to the number-average mol.wt. (Mw/Mn) is less than 10; 1-100 pts.wt. crosslinked polyphenylene sulfide resin which has a melt viscosity (300 deg.C, 200/sec) of 5X10<4> P or lower, a number- average mol.wt. of 7000 or lower, and such a mol.wt. distribution that the ratio of Mw/Mn is less than 30; 0.05-10 pts.wt. silane compd. selected from the group consisting of an epoxysilane, a mercaptosilane, and a ureidosilane; and 0-250 pts.wt. fibrous filler.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a polyphenylene sulfide resin composition that can reduce the occurrence of flakes and provide molded articles with excellent mechanical strength.

<Prior art> Polyphenylene sulfide resin (hereinafter abbreviated as PPS resin) has excellent heat resistance, flammability, homogeneity, and electrical insulation properties, making it suitable for engineering plastics. Mainly used for molding, but also for various electrical parts, mechanical parts, and automobile parts.

However, PPS resin generates a relatively large amount of paris during molding, and the actual situation is that its use is particularly limited in applications such as small precision parts that require low paris.

Several studies have been made to improve the Paris properties (difficulty of producing Paris) of PPS resin, for example:
A method of adding an organic alkali metal phosphate compound to PPS resin (Japanese Unexamined Patent Publication No. 64-54066), a method of blending highly crosslinked PPS resin as a Paris property improver (
JP-A No. 64-9266) and a method of adding a silane compound to PPS resin (JP-A No. 63-251430), but the effect of improving the Paris properties by these methods is not at a satisfactory level. It is difficult to say that this has been achieved.

On the other hand, PPS resins are generally made of polymers with relatively low molecular weight obtained by the manufacturing method typified by the description in Japanese Patent Publication No. 45-3368, and polymers obtained by the manufacturing method typified by the description in Japanese Patent Publication No. 52-12240. These include substantially linear polymers with relatively large molecular weights.

The relatively low molecular weight polymers are often used after polymerization in the shell by heat treatment in an oxygen atmosphere to form crosslinks, branched structures, etc. to increase the degree of polymerization. 1pps
Although resins have the excellent feature of less generation of flakes during molding, they have several problems such as insufficient mechanical strength and brittleness.

In addition, although the relatively high molecular weight polymer has various characteristics such as mechanical strength, particularly weld strength and impact strength, which are significantly superior to that of cross-linked @pps, it is difficult to avoid the occurrence of paris generated during molding. The problem was that there were too many.

<Problem to be solved by the invention> In view of the above circumstances, the present inventors have developed a substantially linear PP
We began our investigation based on the idea that by blending S resin and cross@pps resin, we could obtain a resin with balanced mechanical strength and molding properties.

The present inventors first investigated blends of substantially linear PPS resin 3-=4- resin and cross@pps resin at various blending ratios, and the results showed that paris could be sufficiently reduced. If you try to do so, the mechanical strength will drop significantly,
However, it has been found that it is difficult to achieve a balance between Paris properties and mechanical strength by simply blending both resins.

Therefore, the present inventors conducted extensive studies with the aim of obtaining a PPS resin composition that has high mechanical strength and generates less flakes during molding, and as a result, the inventors of the present invention have developed a method that combines a substantially linear PPS resin and a cross-linked wpps resin. The present inventors have discovered that the above object can be efficiently achieved by adding at least one silane compound selected from epoxysilane, mercaptosilane, and ureidosilane as a third component during blending, leading to the present invention. .

Means for Solving the Problems> That is, the present invention provides (A) a number average molecular weight (Mn) of 7.0 as determined by gel permeation chromatography using 1-chloronaphthalene as a solvent. O00 or more and having a molecular weight distribution in which the ratio of number average molecular weight to weight average molecular weight (M w ) satisfies the following formula 0, (B) the same as above. The number average molecular weight (Mn) determined by the method is 7,000 or less, the ratio of the number average molecular weight to the weight average molecular weight (M w ) satisfies the following formula 0, and the melt viscosity (300 1 to 100 parts by weight of a cross-linked PPS resin whose temperature (°C, 200/sec) is 5 x 104 borides or less, (C) 0.05 to 100 parts by weight of at least one silane compound selected from epoxysilane, mercaptosilane and ureidosilane. 10
The present invention provides a PPS resin composition containing 0 to 250 parts by weight of the present invention and (D) a fibrous filler.

y layer/Mn<10 ...... ■Mw
/ M n > 30 -- ■ The PPS resin (A), which is the main component in the present invention, can have a structure 2〇.

It is a polymer containing 70 mol % or more, more preferably 90 mol % or more of the repeating unit represented by "1", and if the repeating unit 1 is less than 70 mol %, heat resistance will be impaired, so it is not preferable.

Moreover, the PPS resin as component (A) in the present invention is
The number average molecular weight (Mn) determined by gel permeation chromatography using 1-chloronaphthalene as a solvent is 7,0
00 or more, and the number average molecular weight and weight average molecular weight (
It is important that the ratio of M w ) satisfies the following formula (2) and that the polymer is a substantially linear polymer having a molecular weight distribution.

M w / M n < 10...
... ■Even if a PPS resin that does not satisfy these conditions is used as component (8), sufficient mechanical strength cannot be obtained.

In addition, the PPS resin as component (A) in the present invention is a PPS resin that satisfies the above conditions by adding a repeating unit having the following structural formula, etc., as long as the effects of the present invention are not impaired.
Resin (8) can be produced, for example, by a method typified by Japanese Patent Publication No. 52-12240.

Component FB), which is one of the essential components in the present invention, is also a PPS resin. However, component (B) is component (A
), the number average molecular weight (in) is 7,000 or less, and the number average molecular weight and weight average molecular weight (M w
) It is important that the crosslinked PPS resin has a molecular weight distribution that satisfies the following formula 0, and has a melt viscosity (300° C., 200/sec) of 5×10 4 poise or less.

Mw/Mn＞30 ・・・・・・ ■
When a PPS resin that does not satisfy these conditions is used as component (B), it is possible to obtain a sufficient Paris reduction effect and high mechanical strength at the same time.

As a method for producing PPS resin (B) that satisfies the above conditions, for example, a polymer with a relatively small molecular weight obtained by a production method typified by Japanese Patent Publication No. 45-3368,
A method of introducing a crosslinked structure by heat treatment at a high temperature, for example, 200°C or higher in the presence of oxygen, or a method of introducing a crosslinked structure during polymerization using a crosslinking agent such as polyhalobenzene.
Examples include a method of introducing W4 construction.

In the present invention, the blending amount of the PPS resin as component B> is 1 to 100 parts by weight per 100 parts by weight of component A),
In particular, 10 to 70 parts by weight is suitable. If the blending amount is less than 1 part by weight, the Paris reduction effect will be significantly impaired, and if the blending amount is 100 parts by weight or more, the strength will drop significantly even if the following silane compound is added, which is not preferable.

Next, the epoxysilane compound used as component (C) in the present invention is an alkoxysilane or halosilane having one or more epoxy groups in the molecule,
Specific examples include γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, and β-(3,4-eboA dicyclohexyl)ethyltrimethoxysilane.

Further, the mercaptosilane compound used as component (C) in the present invention is an alkoxysilane or halosilane having one or more mercapto groups in the molecule, and specifically, γ-mercaptopropyltrimethoxysilane and γ- Examples include mercaptopropyltriethoxysilane.

Further, the ureidosilane compound used as component (C) in the present invention is an alkoxysilane or halosilane having one or more ureido groups in the molecule, and specifically, γ-ureidopropyltriethoxysilane, γ-ureidopropyltriethoxysilane, γ-ureidopropyltriethoxysilane, -ureidopropyltrimethoxysilane and γ(
Examples include 2-ureidoethyl)aminopropyltrimethoxysilane.

These silane compounds can be used alone or in the form of a mixture of two or more, and among the above silane compounds, particularly preferred silane compounds include γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, and γ-mercaptopropyltrimethoxysilane. Examples include methoxysilane and γ-ureidopropyltriethoxysilane.

The blending amount of these silane compounds (C) used in the present invention is preferably in the range of 0.05 to 10 parts by weight, particularly 0.1 to 3 parts by weight, based on 100 parts by weight of component (A). If the amount added is less than 0.01 part by weight, the effect of improving mechanical strength will not be sufficiently expressed, and if it exceeds 10 parts by weight, the fluidity of the composition will be significantly impaired, which is not preferable.

In the present invention, the fibrous filler (D) used as necessary includes glass fiber, alumina fiber, silicon carbide fiber, ceramic fiber, asbestos fiber, gypsum fiber,
Examples include fibrous fillers such as metal fibers, non-ms fibers such as titanate whiskers, and carbon fibers, and it is also possible to use two or more types of these fillers in combination. The blending amount of these fibrous fillers (D) is in the range of 0 to 250 parts by weight per 100 parts by weight of component (A), but from the viewpoint of the balance of heat resistance and mechanical strength of the resulting composition, 20-20
A blending amount of 0 parts by weight is preferred, and a blending amount of 40 to 100 parts by weight is particularly preferred. If the blending amount exceeds 250 parts by weight, it is not preferable because the fluidity of the composition will be significantly impaired.

In addition, the PPS resin composition of the present invention may contain other fillers such as wollastenite, sericite, kaolin, mica, clay, bentonite, asbestos, talc, silicic acid such as alumina silicate, etc., to the extent that the effects of the present invention are not impaired. Salt, alumina, silicon chloride, magnesium oxide, zirconium oxide, metal compounds such as titanium oxide, carbonates such as calcium carbonate, magnesium carbonate, dolomite, sulfates such as calcium sulfate, barium sulfate, glass beads, nitride Non-fibrous fillers such as boron, silicon carbide and silica can be added.

Furthermore, the PPS resin composition of the present invention may contain antioxidants such as hindered phenol compounds, hindered amine compounds, thioether compounds, and reducing phosphorus compounds, heat resistant agents, low density or Mold release agents such as high-density polyethylene, partially oxidized polyethylene, silicone, higher fatty acid amides, alkyl esters of higher fatty acids or higher fatty acid esters of polyhydric alcohols such as ethylene glycol, butanediol, glycerin, and pentaerythritol, metals of higher fatty acids Additives such as lubricants such as salts, coloring agents such as pigments and dyes, halogen-based or non-halogen-based flame retardants, and small amounts of other types of polymers can be added.

The method for preparing the PPS resin composition of the present invention is not particularly limited, but a mixture of raw materials may be fed to a commonly known melt mixer such as a single-screw or 22-screw extruder, a Banbury mixer, a kneader, and a mixing roll. te28
Examples include a method of kneading at a temperature of 0 to 380°C. Furthermore, there is no particular restriction on the mixing order of the raw materials.

<Example> The present invention will be explained in more detail with reference to Examples below.

Tensile strength, bending strength, bending modulus, isot impact strength, weld strength,
The molecular weight, molecular weight distribution, and Paris length were each measured according to the following methods.

Tensile strength: ASTM-D638 Bending strength: ASTM-D790 Flexural modulus: ASTM-D790 Izot impact strength: ASTM-D250 Measurement of weld strength: Gates at both ends, weld line near the center of the specimen Injection molded ASTM J dumbbell pieces with a strain rate of 5 ram/II! The tensile strength was measured under the following conditions: n, and the distance between the fulcrums was 64 ㎫.

Measurement of molecular weight and molecular weight distribution: Using a gel permeation chromatography device manufactured by WaterS, “Kobunshi Saishu” Vol. 44, (1987) February issue, 13
It was carried out according to the method disclosed on pages 9-141.

Measurement of Paris Length A STM No. 4 Genbel piece with a gate at one end and a gap for degassing at the other end was heated at a resin temperature of 290 to 330°C and a mold temperature of 120 to 150°C. Injection molding was carried out under the following conditions, and the length of the cracks generated in the gap for scraping of the obtained dumbbell piece was measured. The shorter the Paris length, the better the Paris characteristics.

Reference Example> The PPS resin bulk powder used in this practical example and comparative example is shown below. Further, these characteristic values are shown in Table 1.

Linear PP5 pps-i: manufactured by Toshi Phillips Vetroleum Co., Ltd., M2588 2: manufactured by Toshi Phillips Vetroleum Co., Ltd., M2888 Cross-linked PP5 PPS-3: manufactured by Toshi Phillips Vetroleum Co., Ltd.
M2100 PPS-4: Manufactured by Toshi Phillips Vetroleum Co., Ltd.
M2900 Examples 1 to 4 After tri-blending pps-i, PP5-3, γ-glycidoxypropyltrimethoxysilane and glass #a fiber in the proportions shown in Table 2, the temperature conditions were set at 290 to 320°C. The mixture was melt-kneaded and pelletized using a screw extruder.

Using the obtained pellets, test pieces for mechanical property evaluation and test pieces for Paris evaluation were molded.

Tensile strength and bending strength measured on the obtained test piece,
The flexural modulus, Izot impact strength, weld strength and par length are shown in Table 3.

Example 5 5 6 Tri-blending, melt-kneading, pelletizing, molding, and physical property evaluation were carried out in the same manner as in Example 1 at the ratios shown in Table 2, except that PP5-2 was used instead of PPS-1. Ta.

The results are shown in Table 3.

Example 6 Tri-blending, melt-kneading, pelletizing, molding, and physical property evaluation were carried out in the same manner as in Example 1, except that PPS-4 was used instead of PPS-3, at the ratios shown in Table 2. Ta. The results are not shown in Table 3.

Example 7.8 Example 1 except that the silane compounds shown in Table 2 were used instead of γ-crisitoxypropyltrimethoxysilane.
Tri-blending, melt-kneading, pelletizing, molding, and physical property evaluation were performed in the same manner as shown in Table 2. The results are shown in Table 3.

Example 9 Tri-blending, melt-kneading, pelletizing, molding, and physical property evaluation were performed in the same manner as in Example 1, except that carbon fibers were used instead of glass fibers, at the ratios shown in Table 2. The results are shown in Table 3.

Comparative Example 1 Tri-blending, melt-kneading, pelletizing, molding, and physical property evaluation were performed in the same manner as in Example 1, except that PP5-3 was used at the ratios shown in Table 2. The results are also shown in Table 3.

It can be seen that sufficient reduction in Paris does not occur when crosslinked PPS resin is not blended.

Comparative Example 2 Tri-blending, melt-kneading, pelletizing, molding, and physical property evaluation were performed in the same manner as in Example 1, except that PPS-1 was not used, at the ratios shown in Table 2. The results are also shown in Table 3.

If linear PPS resin is not blended, mechanical strength is low;
It is also seen that the Paris reduction effect is insufficient.

Comparative Examples 3 to 4 Tri-blending, melt-kneading, pelletizing, molding, and physical property evaluation were performed in the same manner as in Example 1, except that no silane compound was added, at the ratios shown in Table 2. The results are shown in Table 3.

If a silane compound is not added, a sufficient pari reduction effect will not be achieved when attempting to obtain mechanical strength equivalent to that of a linear PPS resin. On the other hand, if an attempt is made to obtain a sufficient Paris reduction effect, the mechanical strength will drop significantly.

Therefore, it can be seen that it is difficult to simultaneously exhibit sufficient mechanical strength and a Paris reduction effect without adding a silane compound.

Table 1 <Effects of the Invention> The polyphenylene sulfide resin composition of the present invention generates little flash during molding and has excellent mechanical strength, and is particularly useful for applications such as small precision parts made by injection molding.

Claims (1)

[Claims] (A) Number average molecular weight (@Mn@) determined by gel permeation chromatography using 1-chloronaphthalene as a solvent.
) is 7,000 or more, and the ratio of number average molecular weight to weight average molecular weight (@Mw@) is based on 100 parts by weight of a substantially linear polyphenylene sulfide resin having a molecular weight distribution that satisfies the following formula (I). , (B) Number average molecular weight (@Mn@) determined by the same method as above is 7,00
0 or less, and the number average molecular weight and weight average molecular weight (@
Mw@) has a molecular weight distribution that satisfies the following formula (II), and has a melt viscosity (300°C, 200/sec) of 5 x 10
1 to 100 parts by weight of a crosslinked polyphenylene sulfide resin having a molecular weight of ^4 poise or less, (C) 0.05 to 10 parts by weight of at least one silane compound selected from epoxysilane, mercaptosilane and ureido silane, and (
D) A polyphenylene sulfide resin composition containing 0 to 250 parts by weight of a fibrous filler. @Mw@／@Mn@＜10・・・・・・(I) @Mw
@／@Mn@＜30・・・・・・(II)