JP2636424B2 - Heat and impact resistant resin composition - Google Patents

Description

The present invention relates to a thermoplastic resin composition having excellent heat resistance and impact resistance, and more particularly, to a polyphenylene ether resin, a rubber reinforced resin, a polystyrene and the like. The present invention relates to a heat- and impact-resistant resin composition comprising a block copolymer of poly (styrene-acrylonitrile) and a hydrogenated product of a block copolymer of a vinyl aromatic compound and a conjugated diene.

[Prior Art] A resin composition comprising a polyphenylene ether resin (hereinafter referred to as PPE) and a rubber reinforced resin is known, and particularly, PPE
The so-called styrene-based resin blend can improve moldability and heat resistance, which are disadvantages of each component resin. However, this two-component blend composition has a problem in application to uses such as automobile exteriors due to insufficient chemical resistance.

To solve this, rubber reinforced resin (hereinafter referred to as ABS)
An attempt has been made to obtain a resin composition with PPE using an acrylonitrile-butadiene-styrene copolymer resin. However, if these resins are simply blended, the compatibility between the resins is poor, so that the impact resistance of the molded product is low and is not suitable for practical use.

Attempts have been made to compatibilize this blend system, and the technique described in JP-A-59-193951 corresponds to this. In this example, a vinyl cyanide compound (hereinafter referred to as A) in ABS to be blended in a composition of PPE and ABS.
N) is controlled, and the copolymerization ratio of the grafted AN in the monomer mixture is particularly 1 to 15% by weight.
It is suppressed to. However, in this case, special AB with low AN content
S must be polymerized separately, and the impact resistance of this composition is not sufficient.

On the other hand, Japanese Patent Application Laid-Open No. 61-62551 discloses a composition obtained by mixing 1 to 5% by weight of a hydrogenated product of a block copolymer of a vinyl aromatic compound and a conjugated diene compound in a composite system of PPE and ABS. Proposed and found that this composition is excellent in impact resistance, appearance and chemical resistance. However, the ABS used in this composition is also a specialty ABS with an AN content of substantially 1 to 15% by weight, and thus the A in the final composition
It is difficult to say that the N content is low and the chemical resistance is still sufficient.

Further, JP-A-64-54052 discloses that a composition of PPE and ABS is mixed with 10 to 60 parts by weight of a block copolymer having both a unit compatible with PPE and a unit compatible with ABS. A resin composition comprising: However, the physical properties of this composition, particularly the Izod impact strength, are as low as 3 to 5.4 kg · cm / cm, and it is hard to say that the composition is a sufficient material to be applied to the exterior of automobiles and chassis of OA equipment. Furthermore, block copolymers used as compatibilizers are expensive, and it has been desired to reduce the amount used.

[Problems to be solved by the invention]

The problem to be solved by the present invention is that when producing a resin composition comprising PPE and ABS, PPE which is inherently poorly compatible
And so-called general ABS having an AN content of 15 to 40% by weight, and to search for an additive that dramatically improves the impact resistance of the resin composition. As a result, there is a need to develop an inexpensive resin material having a high level of impact resistance and chemical resistance applicable to interior and exterior parts of automobiles.

[Means for solving the problem]

The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, as a compatibilizer for a composition of PPE and general ABS, a block copolymer made of polystyrene and styrene-acrylonitrile copolymer, By adding a hydrogenated product of a block copolymer consisting of a vinyl aromatic compound and a conjugated diene as an impact modifier, an inexpensive resin composition with high heat and impact resistance and excellent chemical resistance can be obtained. And reached the present invention.

That is, the present invention relates to a rubber reinforced resin obtained by graft copolymerizing (a) 10 to 90% by weight of a polyphenylene ether resin and (b) a vinyl cyanide compound and a vinyl aromatic compound with an elastic rubber phase. (C) the weight of styrene alone per 100 parts by weight of a resin composition consisting of 90 to 10% by weight of a rubber reinforcing resin in which the vinyl cyanide compound monomer in the monomer mixture to be copolymerized is 15 to 40% by weight; A block copolymer having a united body as one segment (A) and a copolymer composed of styrene and acrylonitrile as another segment (B), having a number average molecular weight of 50,000 to 200,000, and a segment (A) and a segment. (B) 0.5 to 10 parts by weight of a block copolymer having a weight composition ratio of 20/80 to 60/40, (d) hydrogenation of a block copolymer of a vinyl aromatic compound and a conjugated diene A heat-resistant / impact-resistant resin composition comprising 5 to 20 parts by weight of a product.

 Hereinafter, the present invention will be described in more detail.

<Polyphenylene ether resin> The polyphenylene ether resin (hereinafter referred to as PPE) used in the present invention is represented by the following general formula (I): Wherein n is at least 50 or more. Q represents a substituent composed of hydrogen, a halogen, a hydrocarbon group, a halogenated hydrocarbon group, or the like.

A typical example of PPE is poly (2,6-dimethyl-1,4-
Phenylene) ether, poly (2,6-diethyl-1,4-phenylene) ether, poly (2-methyl-6-ethyl-
1,4-phenylene) ether, poly (2-methyl-6-
Propyl-1,4-phenylene) ether, poly (2,6-dipropyl-1,4-phenylene) ether, poly (2-ethyl-6-propyl-1,4-phenylene) ether, 2,6
-A copolymer of dimethylphenol and 2,3,6-trimethylphenol, among which the most preferred is poly (2,6-dimethyl-1,4-phenylene) ether, or
It is a copolymer of 2,6-dimethylphenol and 2,3,6-trimethylphenol.

Methods for producing these polyphenylene ethers (PPE) corresponding to the above general formula (I) are known and described in, for example, U.S. Pat. Nos. 3,306,874, 3,306,875, 3,257,357 and 3,257,358.

<Rubber Reinforced Resin> The rubber reinforced resin (hereinafter referred to as ABS) in the present invention is obtained by graft copolymerizing a vinyl cyanide compound and a vinyl aromatic compound with an elastic rubber phase, As a graft phase to the rubber phase, ABS obtained by copolymerizing a monomer mixture of a vinyl cyanide compound and a vinyl aromatic compound having a vinyl cyanide compound unit content in the range of 15 to 40% by weight is meant. I do. The vinyl aromatic compound used for producing such an ABS is represented by the general formula (II): (Wherein R ¹ is a hydrogen atom, a halogen atom or an alkyl group,
R ² and Z are each a hydrogen atom, a halogen atom, an alkyl group or a vinyl group, and p is an integer of 1 to 5), for example, styrene, α-methylstyrene, vinyltoluene, p -Tertiary butyl styrene, chlorostyrene and the like. These vinyl aromatic compounds may be used alone or in combination of two or more.

The vinyl cyanide compound has the general formula (III) (R ′ in the formula represents a hydrogen atom or an alkyl group), such as acrylonitrile, methacrylonitrile, α-ethylacrylonitrile, α-propylacrylonitrile and the like. Can be These vinyl cyanide compounds may be used alone or in combination of two or more.

Examples of the elastic rubber phase used in the ABS include polybutadiene, styrene-butadiene copolymer, butadiene-acrylonitrile copolymer, styrene-butadiene-styrene-block copolymer, or a hydrogenated product thereof, EPR, EPDM, etc. Ethylene-propylene copolymer rubber,
Acrylic ester-based copolymer rubber and the like can be mentioned. These elastic rubbers may be used alone or in combination of two or more.

Particularly preferred ABS in the present invention is one using polybutadiene or styrene-butadiene copolymer as the elastic rubber phase, acrylonitrile as the vinyl cyanide compound, and styrene as the vinyl aromatic compound. In addition, the composition has an elastic rubber phase of 5 to 5.
50% by weight, 15 to 40% by weight of vinyl cyanide compound unit,
Those having 10 to 80% by weight of the vinyl aromatic compound unit are preferably used.

As a method for producing such an ABS, any of known emulsion polymerization, bulk polymerization, solution polymerization and suspension polymerization can be used, but emulsion polymerization is preferred.

<Block Polymer Consisting of Polystyrene and Styrene-Acrylonitrile Copolymer> The first feature of the present invention is that a resin composition of PPE and ABS, which are originally incompatible, is used as a compatibilizer in the presence of (c) component polystyrene and styrene. -Use of a block copolymer (hereinafter, referred to as a BL copolymer) composed of an acrylonitrile copolymer. The BL copolymer referred to herein is a (a) a polystyrene (hereinafter referred to as PS) segment (A) compatible with PPE as a component resin, and a styrene / polystyrene (B) compatible with ABS as a (b) component resin. A block copolymer having both an acrylonitrile copolymer (hereinafter referred to as AS) segment (B) and having a number average molecular weight of 500,000 to 2
A block copolymer having a molecular weight ratio of 00,000, particularly preferably 100,000 to 200,000, and a weight composition ratio of the segment (A) to the segment (B) of 20/80 to 60/40, more preferably 30/70 to 60/40. means. Such a BL copolymer can be obtained, for example, by performing multi-stage polymerization using a radical polymerization initiator such as a polymeric peroxide.

The method for producing this BL copolymer is described in
As described in detail in Vol. (2), page 81 (1987), for example, the following method can be adopted.

That is, 1 g of an organic dispersant such as polyvinyl alcohol is dissolved in 200 g of pure water in a flask, and the temperature is raised to 60 ° C. under a nitrogen stream. Into which formula (IV) Polymeric peroxide (ATPPO) represented by
A styrene monomer (ST) in which 5.26 g was dissolved was added, and polymerization was started at the same temperature. After 2 hours, the polymerization suspension is cooled,
The resulting polymer is separated by filtration, washed with water, and dried to obtain 98 g of polystyrene (hereinafter, referred to as PO-PS) containing an OO bond in a chain.

Next, this PO-PS (Mn @ 60,000, active oxygen content 0.16%) 50
g was added to a 500 ml flask containing 300 g of water in which partially saponified polyvinyl alcohol was dissolved, and 50 g of a mixed monomer of ST and acrylonitrile (AN) was further added.
After stirring for an hour, PO-PS was impregnated with the mixed monomer.
Subsequently, the temperature was raised to 75 ° C. to initiate polymerization. After 4 hours, the polymerization suspension is cooled, and the resulting polymer is separated by filtration, washed with water, dried,
99 g of a BL copolymer (PS-b-A) as shown in the following (V)
S) get.

The BL copolymer obtained in this way has a poor compatibilizing effect when its number average molecular weight is less than 50,000, while the number average molecular weight is less than 200,
If it exceeds 000, the fluidity of the final composition is undesirably reduced. On the other hand, PS segment (A) and AS of BL copolymer
The weight composition ratio of the segment (B) is particularly preferably from 20/80 to 60/40. Outside this range, the effect of the BL copolymer as a compatibilizer is poor.

As such a BL copolymer, for example, MODIPER BT-3 manufactured by NOF Corporation is exemplified.

<Hydride of Block Copolymer> A second feature of the present invention is to use a hydrogenated product of a block copolymer as an impact modifier. The hydrogenated product of the block copolymer (hereinafter referred to as HB copolymer) used in the present invention is an XYX type (X represents a block composed of a vinyl aromatic compound, and Y represents a block composed of a conjugated diene compound). ) Is a hydrogenated product. Also, the number average molecular weight of the block copolymer is generally 10,000 to 1,000,000,
Preferably it is in the range of 20,000 to 500,000. Further, the content of the vinyl aromatic compound unit in the block copolymer is desirably in the range of 2 to 50% by weight, particularly 5 to 30% by weight. The average molecular weight of the block X is 2,000
The range of 0 to 250,000, and the average molecular weight of block Y is 2,2.
A range from 500 to 70,000 is preferred. The average degree of unsaturation in the copolymer due to the hydrogenated product is 10% of the value before hydrogenation.
%, Particularly preferably 5% or less.
In addition to the hydrogenated product of the block copolymer, the HB copolymer of the present invention includes α, β-unsaturated carboxylic acid represented by maleic anhydride, citraconic anhydride, or itaconic anhydride in the HB copolymer. A modified block copolymer grafted with an anhydride (hereinafter referred to as a modified HB copolymer) can also be used. In this case, the amount of grafting of the α, β-unsaturated carboxylic anhydride onto the HB copolymer is preferably 0.2 to 5 parts by weight based on 100 parts by weight of the HB copolymer as the backbone polymer. Outside this range, the physical properties of the final composition deteriorate.

Examples of HB copolymers suitable for the present invention include Clayton G1650, G1651, or G1652, commercially available from Shell Chemical Company. The modified HB copolymer is exemplified by Creton FG1901X of the same company.

<Composition ratio of final composition> Regarding the mixing ratio of PPE and ABS in the resin composition in the present invention, PPE is in the range of 10 to 90% by weight and ABS is in the range of 90 to 10% by weight. When the content of PPE is less than 10% by weight, the heat resistance characteristic of this resin is lost, so that the final composition has no practical value. On the other hand, when the content exceeds 90% by weight, the workability deteriorates.

In the present invention, 0.5 to 10 parts by weight of the BL copolymer of the component (c) and 5 to 10 parts by weight of the HB copolymer (d) are added to 100 parts by weight of the resin composition of both the components (a) PPE and (b) ABS.
It is blended in the range of ~ 20 parts by weight. If (c) is less than 0.5 part by weight, the impact resistance of the final composition is low due to poor compatibility of the two component resins (a) and (b), and if it exceeds 10 parts by weight, the heat resistance of the final composition is low. The cost will increase as well as decrease. If the component (d) is less than 5 parts by weight, the impact resistance of the final composition is low, and if it exceeds 20 parts by weight, the heat resistance and chemical resistance of the final composition deteriorate.

Polystyrene, impact-resistant polystyrene, AS resin, or the like can be added to the composition of the present invention, if desired, as long as the characteristics can be maintained.

The composition of the present invention may further contain other additives such as a plasticizer, a stabilizer, an ultraviolet absorber, a flame retardant, a coloring agent, a release agent, and a glass fiber, a fibrous reinforcing agent such as carbon fiber, and a glass bead. , Calcium carbonate, talc and the like can be added.

As the plasticizer, epoxidized soybean oil, polyethylene glycol, low molecular weight polyethylene and the like are effective.

Examples of the stabilizer include phosphites, hindered phenols, zinc dithiocarbamates, metal oxides and the like, and these can be used alone or in combination.

As the flame retardant, aromatic phosphates, red phosphorus, aromatic halogen compounds, antimony trioxide and the like are particularly effective.

As a method of mixing the components constituting the composition of the present invention, any method may be used, and for example, a method using an extruder, a heating roll, a Banbury mixer, a kneader, or the like can be used.

〔The invention's effect〕

The heat-resistant and impact-resistant resin composition of the present invention is particularly excellent in mechanical properties represented by impact resistance, appearance, moldability, and high chemical resistance. It can be applied as a useful material for electronic parts, office equipment housing / chassis, precision equipment, etc.

〔Example〕

Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

In addition, each performance of the final composition was measured as follows.

(1) Impact strength: Measured according to ASTM D-256.

(2) Tensile strength: Measured according to ASTM D-638.

(3) Flexural modulus: Measured according to ASTM D-790.

(4) Appearance: JIS defines 60 degree specular gloss of dumbbell specimen
It was measured by Z-8741.

(5) Chemical resistance: Two ASTM D-638 dumbbell test pieces were immersed in cyclohexane, taken out after 72 hours, subjected to a tensile test, and compared with the value before immersion to calculate the retention of the value. .

Tensile strength retention = (tensile strength after immersion / tensile strength before immersion) × 100 (6) Heat deformation temperature: Measured according to ASTM D-648.

 Parts or% in each example are based on weight.

Production Example-1 A special ABS having a low AN content was produced as a pair.

Polybutadiene latex and styrene-butadiene copolymer rubber latex are mixed at a weight ratio of 2: 1,
It was prepared so as to have a solid content of 24 parts, and charged in an autoclave together with 100 parts of pure water. After replacement with nitrogen, the temperature was raised to 70 ° C., and a first monomer phase containing 9 parts of AN, 21 parts of styrene (ST) and 0.1 part of tertiary decyl mercaptan (TMD),
And an aqueous solution in which 0.1 part of potassium persulfate (KPS) was dissolved in 50 parts of water was added continuously over 3 hours. Thereafter, a second monomer phase containing further 2 parts of AN, 44 parts of ST and 0.1 part of TDM, and An aqueous solution in which 0.1 part of KPS was dissolved in 50 parts of water was continuously added over 4 hours. After completion of the addition, the polymerization was continued at 70 ° C. for another 2 hours. The conversion of all charged monomers to polymer was 93%. After the salting-out, the polymer recovered by washing with water in a furnace was analyzed after drying, and the composition weight ratio of the ungrafted polymer was AN / ST = 13/87. The rubber content was 25%.

Example-1 40 parts of poly (2,6-dimethyl-1,4-phenylene) ether of Hls, [η] = 0.42 parts in chloroform, and DP-10 of ABS (manufactured by Kyodo Polymer, 25% rubber content) , AN / ST (weight ratio) = 26/74) 60 parts (PPE / ABS (weight ratio) = 40/60)
Nippon Oil & Fats Co., Ltd.
-3 (a block copolymer of polystyrene (PS) and acrylonitrile-styrene copolymer (AS), the weight ratio of which is 50/50, the AN amount in AS = 30%, the number average molecular weight (M
n) is about 140,000) in 8 parts, and further as a HB copolymer, Kleton G1652 (ST-butadiene (B
d) Hydrogenated block copolymer of -ST, PS content is 29% and η _{SOL at} 25 ° C. = 550 cps)
Weigh 10 parts each and mix with a blender.
The mixture was extruded with an extruder set to ° C. and pelletized. Using the pellets, an ASTM test piece was molded by an injection molding machine, and the physical properties described above were evaluated. The results are shown in Table 1. In particular, the mechanical properties represented by impact resistance were excellent, and the chemical resistance and gloss were also good.

Example 2 In Example 1, the mixing ratio of PPE and ABS was changed to PPE / ABS.
(Weight ratio) = 60/40, except that it was carried out in the same manner as in Example-1. Table 1 shows the results. The composition of this example was also excellent in performance.

Example-3 Clayton G1 as the HB copolymer in Example-1
Clayton G1650 instead of 652 (ST min = 29%, η _SOL =
1,500 cps), except that 10 parts were used. Table 1 shows the physical property evaluation results of the composition, which showed excellent physical properties.

Example-4 In Example-1, the rubber content was 40% as ABS, and AN / ST was used.
= 25/75, except that 60 parts of DP-611 manufactured by Kyodo Polymer Co., Ltd. were used. Incidentally, PPE / ABS (weight ratio) = 40/60. The physical property evaluation data is shown in Table 1, and this composition was also excellent in physical properties.

Comparative Example-1 Except that the special ABS (DP-01, rubber content = 25%, AN / ST (weight ratio) = 13/87) of Production Example-1 having a low AN content was used as the ABS in Example-1. Was carried out exactly as in Example-1. As shown in Table 1, the performance of this composition was different from that of Example 1 in impact strength (IS) and heat distortion temperature (HD).
T) was low, and especially the chemical resistance and gloss were poor.

Comparative Example-2 In Example-1, instead of MODIPER BT-3 manufactured by NOF Co., Ltd. as the BL copolymer, MODIPER B-600 (a block copolymer of PS and AS, the weight ratio of which was 70/30) was used instead of MODIPER BT-3. And AN in AS = 30% and Mn = 82,000)
Was performed in exactly the same manner as in Example 1 except that the same amount was used.
The results of evaluating the physical properties of this composition are shown in Table 1. The composition of this example has a lower IS than the example using BT-3, and has a lower HD.
T was also low.

Comparative Example-3 This is an example in which a similar experiment was performed in Example 1 without using a BL copolymer. The results are shown in Table 1. The composition had very low impact strength as compared with Example-1.

Comparative Example-4 This is an example in which a similar experiment was performed without using the HB copolymer in Example-1. Table 1 shows the results. This composition had a lower IS and a lower gloss than that of Example 1.

Comparative Example-5 An experiment and evaluation were performed in the same manner as in Example-1 as a simple PPE / ABS (weight ratio) = 40/60 composition without using both the BL copolymer and the HB copolymer in Example-1. The results are shown in Table 1. It was found that the IS was extremely low and was not suitable for practical use.

Example -5 The same procedure was performed as in Example 1 except that the same amount of PPE from Hls (grade No. X-4671, containing 3% polystyrene) was used as the PPE. As shown in Table 2, the results showed that this composition had high physical property values and excellent chemical resistance, similarly to Example 1.

Example -6 This is an example in which PPE / ABS (weight ratio) was fixed to 40/60, and an experiment was performed in the same manner as in Example 1 using 5 parts of a BL copolymer and 15 parts of an HB copolymer. is there. The results are shown in Table 2, except that the composition of this example has a slightly lower strength and elastic modulus than that of Example 1, but has other physical properties, especially high IS,
The chemical resistance and gloss were also excellent.

Example -7 In this example, a glass fiber (glass fiber T-34 for ABS manufactured by NEC Corporation) surface-treated with the composition of Example 1 was blended so as to be 30% with respect to the base resin composition and pelletized. This is an example of evaluating the physical properties of a test piece obtained by injection molding under a cylinder temperature condition of 300 ° C. The results are shown in Table 2. From the results, it can be seen that when glass fiber (GF) is added to the resin composition of the present invention to a concentration of 30%, the IS is considerably reduced, but the conventional PPE / ABS composition has The value is considerably higher than that of the GF filler, and is considered to be useful as a material for OA equipment and the like.

Example 8 In this example, a flame retardant mixture (decapromodiphenyl ether and antimony trioxide was added to the resin composition of Example 1 at 78/22).
This is an example of an experiment conducted in the same manner as in Example 1 for a composition obtained by adding 13.5% (mixed at a ratio of (weight ratio)). The results are shown in Table 2. Although the IS was considerably reduced, it was at a very high level as compared with the value of the conventional flame-retardant resin composition of ABS / PPE.

Example -9 In this example, a glass fiber and a flame retardant mixture were added to the resin composition of Example 1 so as to be 30% and 13.5%, respectively. It is. Also in this case, the molding temperature was 300 ° C. The physical properties of this final composition are shown in Table-2. It was found that a considerably higher level of physical properties was maintained as compared with the conventional flame-retardant high-rigidity resin composition.

COMPARATIVE EXAMPLE-6 This example provides a composition of PPE / ABS (weight ratio) = 5/95 outside the scope of the present invention, 8 parts of BL copolymer and 10 parts of HB copolymer.
This is an example in which an experiment was conducted in the same manner as in Example 1 with the addition of a part. The evaluation results of this composition are shown in Table 2, but the impact strength and heat resistance were low and did not meet the purpose of the present invention.

Comparative Example-7 In the present example, contrary to Comparative Example-6, the weight ratio of PPE / ABS was 95/5, and 8 parts of the BL copolymer and 10 parts of the HB copolymer were added. This is an example in which physical properties of a test piece molded after mixing and extruding were evaluated. The results are shown in Table 2, and this example was also extremely low in impact resistance and not suitable for practical use.

Comparative Example-8 In this example, the weight ratio of PPE / ABS was the same as that of Example-1.
0/60, but 25 parts of BL copolymer and 3 parts of HB copolymer
This is an example of evaluating a molded specimen after mixing and extruding in the same manner as in Example 1 by obtaining a part and a composition outside the scope of the present invention. The results are shown in Table 2, and this example was also low in impact resistance and heat resistance, and was poor in practicality.

Comparative Example-9 This example is the special A of Production Example-1 having a low AN content as ABS.
Using BS (DP-01), PPE / ABS (weight ratio) = 60/40,
8 parts and 10 parts of BL copolymer and HB copolymer were added to this.
In addition, 62.7 parts and 28.2 parts of a mixture of glass fiber and a flame retardant were added to obtain a composition similar to that of Example 9, and the same procedure as in Example 1 was carried out. The results are shown in Table-2.
The impact resistance was lower than that of No. 9.

Claims (1)

(57) [Claims] 1. A rubber-reinforced resin obtained by graft copolymerizing a vinyl cyanide compound and a vinyl aromatic compound with an elastic rubber phase (a) 10 to 90% by weight of a polyphenylene ether resin. (C) Styrene homopolymer based on 100 parts by weight of a resin composition comprising 90 to 10% by weight of a rubber reinforcing resin in which the vinyl cyanide compound monomer in the monomer mixture to be polymerized is 15 to 40% by weight. Is a block polymer having one segment (A) and a copolymer comprising styrene and acrylonitrile as another segment (B), the number average molecular weight of which is 50,000 to 200,000, and
The weight composition ratio of segment (A) to segment (B) is 20
0.5 to 10 parts by weight of a block polymer of / 80 to 60/40, and (d) 5 to 20 parts by weight of a hydrogenated product of a block copolymer of a vinyl aromatic compound and a conjugated diene. Impact resin composition.