JPH06166805A - Resin composition for molding - Google Patents

Abstract

PURPOSE:To obtain the subject compsn. excellent in resistances to heat and solvents, mechanical characteristics, dimensional stability, and flame retardancy and also in melt flowability and moldability by compounding a specific arom. polyester with a specific polyphenylene sulfide. CONSTITUTION:This resin compsn. comprises 95-50wt.% arom. polyester consisting of structural units of formulae I, II, and III (wherein R is a 1-10C divalent aliph. hydrocarbon group) in an equivalent ratio of the units of formula II to those of formula III of (50:50) to (80:20) and 5-50wt.% polyphenylene sulfide consisting substantially of structural units of formula IV. The compsn. has a good moldability including a good melt flowability and gives a molded article excellent in resistances to heat and solvents, mechanical characteristics, flame retardancy, and dimensional stability.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel molding resin composition, more specifically, heat resistance, mechanical properties, dimensional stability, solvent resistance, flame retardancy mainly composed of amorphous aromatic polyester. The present invention relates to a thermoplastic resin composition having excellent fluidity when melted.

[0002]

2. Description of the Related Art Aromatic polyesters are amorphous polymers, depending on the combination of their constituent components or their copolymerization composition.
A crystalline polymer or a liquid crystalline polymer having various properties can be obtained. Among these, amorphous polymers are excellent in dimensional stability, transparency, mechanical properties, heat resistance, etc.,
Various studies have been conducted as so-called amorphous engineering plastics. In particular, using terephthalic acid and isophthalic acid as acid components,
A polymer using 2,2-bis (4-hydroxyphenyl) propane (hereinafter referred to as "bisphenol A") as a diol component has relatively balanced physical properties, and development is promoted by taking advantage of this. Although it is
Like ordinary amorphous polymers, this polymer has insufficient solvent resistance, is easily dissolved or swelled in various organic solvents, and its use is limited.

For the purpose of improving the solvent resistance, it has been proposed that a part of hydroquinone is used as a diol component (JP-A-52-78999). The hydroquinone component-introduced polymer is certainly improved in solvent resistance and stress crack resistance as compared with a polymer using bisphenol A alone as a diol component. However, it cannot be said that a polymer having such excellent characteristics still has sufficiently satisfactory properties in terms of strength and elastic modulus, like other amorphous polymers. In addition, in such an amorphous polymer, when the degree of polymerization is not sufficiently high, there is a problem in safety because it causes combustion, especially drip, but on the contrary, when the degree of polymerization is increased, the melt viscosity is increased. If the temperature becomes too high, the fluidity at the time of melting deteriorates, causing a problem in moldability.

[0004]

Therefore, the main object of the present invention is to provide a molded article having excellent heat resistance, mechanical properties, solvent resistance, flame retardancy, and dimensional stability, and to provide a fluidity when melted. The present invention is to provide a resin composition having good moldability.

[0005]

The molding resin composition of the present invention is substantially composed of the components of the following formulas (I), (II) and (III), and the component (II) and the component (II) Polyphenylene sulfide consisting of 95-50% by weight of an aromatic polyester having a content equivalent ratio of III) of 50 / 50-80 / 20 and substantially 5-50 polyphenylene sulfide consisting of repeating units of the following formula (IV)
%, And a novel molding resin composition containing 40% by weight or less of a fibrous reinforcing material having an aspect ratio of 10 or more, if necessary.

[0006]

[Chemical 2]

The aromatic polyester constituting the resin composition of the present invention is an amorphous random copolymerized polyester consisting essentially of the components (residues) of the above formulas (I), (II) and (III). Is.

In the above formula (III), R has 1 carbon atom.
It represents a divalent aliphatic hydrocarbon group of 10 to 10, and specific examples of R include the following.

[0009]

[Chemical 3]

Among the components (residues) represented by the above formula (III), the residue from bisphenol A is particularly preferable.

The component (I
The content equivalent ratio of I) and component (III) is 50 / 50-80.
It is necessary to be within the range of / 20. If the content equivalent ratio is out of this range, it becomes a crystalline polymer and has a high melting point, which makes molding difficult, and a polymer having sufficient solvent resistance cannot be obtained. The content equivalent ratio of these components (II) and (III) is 55 / 45-
75/25 is preferable, and 60/40 to 70 /
A value of 30 is particularly preferable.

The method for producing the above-mentioned aromatic polyester used in the present invention is not particularly limited, but for example, (a)
Isophthalic acid and / or its forming derivative, (b) hydroquinone and / or its ester forming derivative,
And (c) a diphenol represented by the following formula (C) and / or an ester-forming derivative thereof in a total amount of the component (b) and the component (c) of 95 to 120 relative to the component (a).
It is mixed in the range of mol% and these are mixed in the presence of a catalyst for 3
A method of heating and melt polycondensation at a temperature of 40 to 400 ° C. can be preferably used.

[0013]

[Chemical 4]

The diphenols represented by the above formula (C) are, for example, 2,2-bis (4-hydroxyphenyl) propane (abbreviation bisphenol A), 2,2
Examples thereof include -bis (4-hydroxyphenyl) butane and 1,1-bis (4-hydroxyphenyl) cyclohexane. Of these, bisphenol A is preferred.

In the production of this polyester, isophthalic acid and / or its ester-forming derivative is used as the acid component (a). Examples of the ester-forming derivative include alkyl ester, aryl ester, and acid chloride. As the acid component (a), isophthalic acid diaryl ester is preferable, and diphenyl isophthalate is particularly preferable.

As the diol component, hydroquinone and / or its ester-forming derivative is used as the above formula (C).
The diphenols represented by and / or their ester-forming derivatives are used. Examples of the ester-forming derivative in this case include a lower aliphatic carboxylic acid ester, and an acetic acid ester is particularly preferable. Above all, it is preferable to use hydroquinone as the component (b) and bisphenol A as the component (c).

The use ratio (copolymerization ratio) of the component (b) and the component (c) is 50/50 to 80 / in terms of molar ratio (b / c).
20. If the mole fraction of component (b) is less than 50%, the solvent resistance targeted by the present invention will be insufficient,
If it is more than 80 mol%, the polymer obtained tends to be crystalline. The molar ratio (b / c) between the component (b) and the component (c) is preferably 55/45 to 75/25, particularly preferably 60/40 to 70/30.

In the process for producing an aromatic polyester used in the present invention, the total amount of the component (b) and the component (c) is mixed with the component (a) in the range of 95 to 120 mol%, Is polycondensed by heating. The total amount of the component (b) and the component (c) is preferably in the range of 97 to 115 mol%, particularly preferably 99 to 110 mol%.

Each of the above components is heated and melt-polycondensed in the presence of a catalyst to form a polymer. As the catalyst used here,
Conventionally known compounds used in the production of polyester, for example, antimony compounds such as antimony trioxide, tin compounds such as stannous acetate, titanium compounds such as titanium tetrabutoxide, and germanium compounds such as germanium oxide are used. The amount of the catalyst used is not particularly limited, but is preferably about 0.1 mol% or less based on the above component (a).

The polymerization temperature during the heat polycondensation is 340 to 4
Set to 00 ° C. Here, the polymerization temperature means the temperature at the latter stage of polymerization or at the end thereof. Polymerization temperature is 340 ℃
If it is lower, the melt viscosity of the polymer becomes higher, so that it is not possible to obtain a polymer having a high degree of polymerization, and if it is higher than 400 ° C., deterioration of the polymer or the like is likely to occur, which is not preferable.

At this time, it is preferable that the initial temperature of the polymerization reaction is set to a relatively low temperature, and the temperature is gradually raised to the above-mentioned polymerization temperature finally. The reaction temperature of the initial polymerization reaction is preferably 150 to 280 ° C, more preferably 180 to 250 ° C.
Is. This polymerization reaction is carried out under normal pressure or reduced pressure, but it is preferable that the initial polymerization reaction is carried out under normal pressure and gradually reduced. At atmospheric pressure, it is preferable to use an atmosphere of an inert gas such as nitrogen or argon. The polycondensation reaction time is not particularly limited, but is about 1 to 10 hours.

The aromatic polyester used in the present invention has an intrinsic viscosity of 0.3 to 1 measured at 35 ° C. in a phenol / 1,1,2,2-tetrachloroethane mixed solvent (weight ratio 60/40). It is preferably 0.0. When the intrinsic viscosity is lower than 0.3, the heat resistance and toughness of the polymer are insufficient, and when it is higher than 1.0, the fluidity at the time of melt-molding the resin composition decreases, which is not preferable. The reduced viscosity is particularly preferably 0.4 to 0.8.

On the other hand, polyphenylene sulfide is composed of a repeating unit represented by the following formula (IV),

[0024]

[Chemical 5]

A polymer abbreviated as "PPS".
Generally, for example, a polymer having a relatively small molecular weight obtained by the production method represented by JP-B-45-3368 and an essentially linear polymer obtained by the production method represented by JP-B-52-12240. There are polymers of relatively high molecular weight and the like, and in the polymer obtained by the method described in Japanese Patent Publication No. 45-3368, the crosslinking agent such as peroxide is heated by heating in an oxygen atmosphere after polymerization. It is also possible to increase the degree of polymerization by adding and heating. In the present invention, PPS obtained by any method can be used, but an essentially linear polymer having a relatively high molecular weight is more preferably used. As this PPS, a commercially available product can be used.

The molding resin composition of the present invention comprises the above-mentioned aromatic polyester and polyphenylene sulfide (PPS).
And a fibrous reinforcing material contained as necessary.

Examples of the fibrous reinforcing material include glass fiber, carbon fiber, aramid fiber, silicon carbide fiber, alumina fiber, potassium titanate fiber and the like. This fibrous reinforcing material has an aspect ratio of 10 or more. Here, the aspect ratio is the ratio of the length of a fiber to its diameter. When there is a distribution in the aspect ratio of the reinforcing fiber, the average value is used as the aspect ratio of the fiber. If the aspect ratio is less than 10,
Reinforcing effect on mechanical properties, heat resistance, etc. is insufficient, which is not preferable. Of the above-mentioned fibers, glass short fibers are preferable as the fibrous reinforcing material.

These fibrous reinforcing materials are preferably those to which a surface treating agent such as a coupling agent or a sizing agent is appropriately added in order to improve the affinity with the aromatic polyester or PPS or the handleability of the fibers themselves. Used. Further, in the resin composition of the present invention, a release agent other than the above,
You may mix | blend various additives, such as an oxidation stabilizer and a pigment.

The mixing ratio of the aromatic polyester, PPS, the fibrous reinforcing material, etc. is 5 to 50% by weight of PPS relative to 95 to 50% by weight of aromatic polyester. When the fibrous reinforcing material is included, the ratio is 40% by weight or less of the total composition. A preferable mixing ratio is 90 to 90% of aromatic polyester.
50% by weight, PPS10 to 50% by weight, fibrous reinforcing material 1
0 to 50% by weight, particularly preferably 85 to 50% by weight of aromatic polyester, 10 to 50% by weight of PPS, and 15 to 50% by weight of fibrous reinforcing material.

The aromatic polyester, PPS and the fibrous reinforcing material can be mixed by a conventionally known compounding method. When the three components are mixed, all of them may be mixed at once, but the remaining components may be mixed with the mixture of the two components in advance.

[0031]

The aromatic polyester, which is the main constituent of the resin composition of the present invention as described above, is an amorphous polymer having a high glass transition temperature, and the composition of the present invention comprising this and PPS or further fibrous reinforcement. The preferred resin composition of the present invention containing a material is excellent in fluidity during melting, heat resistance, mechanical properties, dimensional stability, chemical resistance, and flame retardancy, and is extremely useful as a new heat resistant resin. It can be used in a wide range of fields, and its industrial significance is extremely great.

[0032]

The present invention will be described in detail below with reference to examples, but the present invention is not limited thereto. "Part" in the examples
Means "parts by weight". The intrinsic viscosity of polyester is a value measured at 35 ° C. using a phenol / 1,1,2,2-tetrachloroethane mixed solvent (weight ratio 60/40). The glass transition point (Tg) of polyester is DS
It was measured using C at a temperature rising rate of 10 ° C./min.

The reference example is a production example of an aromatic polyester constituting the resin composition of the present invention.

[0034]

[Reference Example] 318 parts of diphenyl isophthalate, 84 parts of hydroquinone and 75 parts of bisphenol A, 0.09 part of antimony trioxide (catalyst) and 0.33 part of triphenyl phosphate (stabilizer), a stirrer and a nitrogen inlet. The mixture was placed in a reaction vessel having a vacuum distillation system provided, reacted at 240 ° C. for 30 minutes in a nitrogen stream under normal pressure, and then allowed to stand for 34 hours in 1.5 hours.
The temperature was raised to 0 ° C. Next, the pressure was gradually reduced at the same temperature, and after 30 minutes, the pressure was adjusted to about 1 mmHg.

During this period, phenol was generated and distilled off. Polymerization was performed for about 90 minutes under the same conditions to obtain a polymer.

The polymer obtained had an intrinsic viscosity of 0.65 and a glass transition temperature (Tg) of 175 ° C.

[0037]

[Examples 1 and 2] The aromatic polyester obtained in Reference Example and a commercially available glass-reinforced PPS resin (manufactured by Polyplastics Co., Ltd., "Fortron HF-2000") were dry-blended at a ratio shown in Table 1. The polymer was melt-blended using a twin-screw extruder having an inner diameter of 30 mm under the conditions of a polymer temperature of 360 ° C. and an average residence time of 5 minutes. Using an injection molding machine (Japan Steel Works N40A type), the obtained compound was polymer temperature 360 ° C., mold temperature 90 ° C., molding cycle 4
Injection molding was performed under the condition of 0 to 60 seconds.

The physical properties of the molded product thus obtained are shown in Table 1. In addition, in order to evaluate the fluidity, a 0.7 mm thick die for fluidity evaluation was used, and the injection pressure was 1020 kg / cm ^2.
Table 1 also shows the results of the examination of the flow length thereof.

As shown in Table 1, the resin composition of the present invention has excellent heat resistance, mechanical properties and flame retardancy, and
It can be seen that the liquidity has also improved.

[0040]

Comparative Example 1 Examples 1 and 2 except that a predetermined amount of aromatic polyester and a predetermined amount of glass fiber chopped strands (Nippon Electric Glass EX385 aspect ratio 230) were dry blended without using PPS in Examples 1 and 2. The same molding and evaluation as in the above were performed. The results are also shown in Table 1 as Comparative Example 1.

[0041]

Comparative Example 2 The results of the same evaluations made using only the polyester produced in Reference Example are also shown in Table 1 as Comparative Example 2.

[0042]

[Table 1]

Claims (2)

[Claims] 1. Substantially the following formulas (I), (II) and (II)
I)), and (II) and (II)
Molding consisting of 95 to 50% by weight of an aromatic polyester having a content equivalent ratio of I) of 50/50 to 80/20, and 5 to 50% by weight of a polyphenylene sulfide substantially composed of repeating units of the following formula (IV). Resin composition. [Chemical 1] 2. A molding resin composition containing the resin composition according to claim 1 and a fibrous reinforcing material having an aspect ratio of 10 or more in an amount of 40% by weight or less based on the weight of the entire resin composition. .