JPH0643534B2 - Impact resistant polypropylene resin composition - Google Patents

Description

TECHNICAL FIELD The present invention relates to a polypropylene resin composition having remarkably improved impact resistance, and further to a composition having improved mechanical properties and heat aging resistance. It is preferably used for molded articles and the like.

[Conventional technology and its problems]

Polypropylene resin is widely used in industry,
Polypropylene which is a mixture of ethylene and propylene rubber is also known as an impact resistance grade, but it does not necessarily have sufficient impact resistance as compared with ABS resin and the like, and particularly impact resistance at low temperatures. Inferior to. Further, when a large amount of ethylene / propylene rubber is mixed, the impact resistance at room temperature is remarkably improved, but there is a drawback that the heat distortion temperature is significantly lowered.

[Means for solving problems]

The present invention has variously studied the utilization of the unique property of the cyanato group of the compound having a cyanato group (—O—C≡N). As a result, by adding the compound having a cyanato group to ethylene / propylene rubber, The mechanical and thermal properties of ethylene / propylene rubber can be greatly improved (Japanese Patent Application No. 60-183409), and the heat of polypropylene can be improved by adding a small amount of a compound having a cyanato group to polypropylene. It has been found that the stability and the like can be improved (Japanese Patent Application No. 60-048954). As a result of further studies, it was found that a polypropylene resin composition having a significantly improved impact resistance can be obtained by mixing the above modified ethylene / propylene rubber with polypropylene, and the present invention has been completed. .

That is, the present invention is a modified resin obtained by mixing 95 to 70 parts by weight of a polypropylene resin (a) and ethylene / propylene rubber with 5 to 30% by weight of a cyanate ester compound containing at least one cyanato group in the molecule. Quality ethylene / propylene rubber (b)
An impact-resistant polypropylene resin composition obtained by mixing 5 to 30 parts by weight, and in a preferred embodiment, the modified ethylene propylene rubber (b) is impact-resistant modified by the cyanate ester compound. And / or the cyanate ester in which a monofunctional or polyfunctional maleimide compound is additionally blended in an amount of 30% by weight or less, usually 1% by weight or more based on the cyanate ester compound, as a modifying aid for promoting 0.05 to 5% by weight of a catalyst for accelerating the reaction of the compound
Alternatively, a catalyst for crosslinking the ethylene / propylene rubber is used.
05 to 5% by weight are additionally mixed, and further, as a modifying aid for promoting impact resistance modification by the modified ethylene-propylene rubber (b), the components (a) and (b) ) Is added with 0.05 to 5% by weight of 2-mercaptobenzimidazole, and a reinforced impact-resistant polypropylene resin composition further containing a reinforcing agent such as glass fiber. Is provided.

The present invention will be described below.

Polypropylene resin (a) of the present invention (hereinafter referred to as PP)
Is polypropylene for ordinary molding.

The ethylene / propylene rubber (hereinafter referred to as EPR) used in the modified ethylene / propylene rubber composition of the present invention means ethylene, propylene, or these and ethylidene, norbornene, dicyclopentadiene, and other diene compounds as raw materials. Polymerized, normal ethylene / propylene copolymer (= EPM), ethylene / propylene / diene-based monomer copolymer (= EPDM)
It is a rubbery copolymer such as.

Suitable cyanate ester compounds containing at least one cyanato group in the molecule of the present invention, which are used to prepare a modified EPR composition by adding to the above EPR as a modifier, are represented by the following general formula: Is a compound represented by.

General formula (1): R (OCN) m (1) (wherein m is an integer of 1 or more and usually 5 or less, R is an aromatic organic group, and the cyanato group is the organic group). Bound to the aromatic ring of the group) Specific examples include alkylcyanatobenzenes such as monocyanatobenzene, P-tert-butylcyanatobenzene, monocyanatonaphthalene, 1,3- or 1,4 -Dicyanatobenzene, 1,3,5-tricyanatobenzene, 1,3-, 1,4-, 1,
6-, 1,8-, 2,6- or 2,7-dicyanatonaphthalene, 1,3,6-tricyanatonaphthalene, 4,4′-dicyanatobiphenyl, bis (4-dicyanatophenyl) methane, 2,2-bis (4-cyanatophenyl) propane, 2,2-bis (3,5-dichloro-4-cyanatophenyl) propane, 2,2-bis (3,5-
Dibromo-4-cyanatophenyl) propane, bis (4-cyanatophenyl) ether, bis (4-cyanatophenyl) thioether, bis (4-cyanatophenyl) sulone, tris (4-cyanatophenyl) phosphite , Tris (4-cyanatophenyl) phosphate, and cyanate ester obtained by the reaction of novolac with cyanogen halide. In addition to these
8, the same 43-18468, the same 44-4791, the same 45-11712, the same 46-41112,
The cyanate esters described in JP-A-47-26853 and JP-A-51-63149 can also be used.

In addition, the above-mentioned polyfunctional cyanate ester,
Or used as a prepolymer having a cyanato group in the molecule obtained by polymerizing in the presence of a mineral acid, a Lewis acid, a salt such as sodium carbonate or lithium chloride, a phosphoric acid ester such as tributylsulfosphine, an organic metal salt or the like. It can be used as a premixture or a prereactant (= prepolymer) with a monofunctional or polyfunctional maleimide compound described later, and can also be used as a prepolymer with an amine.

EPR of the cyanate ester compound of the present invention described above
The compounding amount for the above is not particularly limited, but is appropriately selected from the range of 5 to 30% by weight. If the added amount is less than 5% or more than 30% by weight, the effect of improving impact resistance is insufficient.

Further, in a preferred embodiment of the present invention, as a modifying aid for promoting impact resistance modification by the cyanate ester compound, 30% by weight or less, usually 1% by weight or more, based on the above cyanate ester compound, is used. In the range of 1, the monofunctional or polyfunctional maleimide compound is additionally compounded. When the blending amount exceeds 30% by weight, the heat resistance such as the heat distortion temperature of the obtained PP resin composition is improved, but the impact resistance becomes insufficient. A preferred compound as the monofunctional or polyfunctional maleimide compound is the following general formula (2).

General formula (2): (In the formula, R ₁ is a monovalent or more and usually pentavalent or less aromatic or alicyclic organic group, X ¹ and X ² are hydrogen, halogen, or an alkyl group, and n is usually an integer of 1 to 5. The maleimides represented by the above formula are prepared by reacting maleic anhydrides with polyamines containing 1 to 5 amino groups to prepare maleamic acid and then dehydrating and cyclizing the maleamic acid. It can be manufactured by a method. Specific examples include N-phenylmaleimide, N-carboxyphenylmaleimide, N-chlorophenylmaleimide, N-methoxyphenylmaleimide, 1,3- or 1,4-bismaleimidobenzene, 1,3- or 1,4 -Bismaleimide cyclohexane, 4,4'-bismaleimide biphenyl, bis (4-maleimidophenyl) methane, bis (4-maleimidophenyl) ether, bis (4-maleimidophenyl)
Sulfone, bis (4-maleimido-3-methylphenyl) methane, bis (4-maleimido-3,5-dimethylphenyl) methane, bis (4-maleimido-3,5-dichlorophenyl) methane, 2,2-bis ( 4-maleimidophenyl) propane, 2,
2-bis (4-maleimido-3-methylphenyl) propane,
2,2-bis (4-maleimido-3,5-dimethylphenyl) propane, 2,2-bis (4-maleimido-3-chlorophenyl) propane, 2,2-bis (4-maleimido-3,5-dichlorophenyl) ) Propane, 2,2-bis (4-maleimido-3,5-dibromophenyl) propane, 1,1-bis (4-maleimidophenyl)
Cyclohexane, 3,4-bismaleimidophenyl-4'-
Maleimidophenylmethane, 1,1-bis (4-maleimidophenyl) -1-phenylmethane, polymaleimide from melamines with S-triazine ring, benzene ring bonded by methylene bond by reaction between aniline and formaldehyde Examples include polymaleimides derived from polyamines.

As appropriate for the preparation of the modified EPR composition, 0.05 to 5% by weight of a compound known as a catalyst for accelerating the reaction of a cyanate ester compound or 0.05 to 5% by weight of a compound known as a catalyst for crosslinking the ethylene-propylene rubber. Additional mixing is possible.

These include, for example, known organic peroxides such as dicumyl peroxide, catalysts for mainly EPR crosslinking such as sulfur, metal salts such as melamine and acetylacetone aluminum, and mainly cyanic acid such as metal chelates. A catalyst for accelerating the reaction of the ester compound is exemplified, and they are used alone or in combination.

Furthermore, by adding 0.05 to 5% by weight of 2-mercaptobenzimidazole at the time of mixing the component (a) and the component (b), it is possible to improve the impact resistance particularly at room temperature.

Reinforcing agents may be included to provide a reinforced composition. The reinforcing material is a weakly alkaline to weakly acidic reinforcing base material such as glass fiber, and the use of the resin composition of the present invention in the range of usually 5 to 40% by weight improves the heat distortion temperature and The impact resistance at low temperatures can be improved. Glass fiber, talc,
In the case of mica, wollastate, calcium carbonate, etc., which are weakly alkaline or weakly acidic, those which have been pretreated with a known surface treatment agent or the cyanate ester compound of the present invention are used for the surface treatment in advance. Is preferred.

The impact-resistant PP resin composition of the present invention is manufactured using the components described above.

First, the method for preparing the modified EPR composition (b) is not particularly limited as long as it is a method in which the added components are uniformly dispersed. For example, the above components are mixed by a blender, a kneader, a Henschel mixer, or other means. Melt mixing with an extruder, etc .; mixing with a kneader, ruder, Henschel mixer, etc., usually at 20 to 180 ° C .; a masterbatch method for producing a high-concentration masterbatch and mixing it. In the case of an extruder, the EPR extrusion conditions can be used as they are. In order to improve the handleability of the modified EPR composition, a method of adding a small amount of the PP resin or other resin of the component (a) of the present invention is also preferable in the above mixing.

Next, the PP resin (a) and the modified EPR composition (b), and optionally,
The method for producing the impact resistant PP resin composition of the present invention by mixing 2-mercaptobenzimidazole and a reinforcing material may be any method in which these components are uniformly dispersed, and is not particularly limited, but is usually By mixing by a roll, a kneader, a ruder, an extruder or the like at a temperature of 180 to 200 ° C. for 1 minute to 1 hour.

The impact-resistant PP resin composition of the present invention is as described above, and includes dyes, pigments, inorganic fillers, metal fibers, powders, flakes, plasticizers, flame retardants, UV absorbers, stabilizers and the like. Known additives, thermoplastic resins, and thermosetting resins can be added as appropriate.

〔Example〕

Hereinafter, the present invention will be described with reference to examples. In addition, the addition amount in the examples and the like is based on weight.

Example-1 A modified PP composition prepared by premixing the components shown in Table 1 was mixed with PP resin, and the mixture was heated at a temperature of 185 ° C. and a pressure of 20.
A flat plate having a thickness of 3 mm was obtained by press molding at kg / cm ² , and a test piece for physical properties was prepared.

The results are shown in Table 1.

The modified EPR composition was prepared by adding the components shown in Table 1 to EPR and kneading with a roll at 80 ° C. for 10 minutes.

In addition, the PP resin and the modified EPR composition are mixed at 185 ° C,
It was carried out by kneading with a kneader for 15 minutes.

The description in Table 1 is based on the following.

・ K1016: PP resin, manufactured by Chisso Corporation, trade name; K1016 density 0.90 melt flow rate (= MFR) 5 g (230 ° C, 2.1
6kg, 10 minutes) ・ EP-11: EPM (EPR), manufactured by Nippon Synthetic Rubber Co., Ltd., trade name; EP-
11, ethylene content 50% by weight, Mooney viscosity 40 (ML1-4
100 ℃) Specific gravity 0.858 Glass transition temperature (Tg) -60 ℃, Melt flow index (= MI) 0.8g (190 ℃, 2.16kg 10 minutes) ・ BPA-CN: 2,2-bis (4-cyanatophenyl) Propane-BMI: Bis (4-maleimidophenyl) methane-BT-10: Prepolymer having a weight average molecular weight of 3 x 10 ³ obtained by heating and stirring 90 parts of BPA-CN and 10 parts of BMI at 140 ° C for 5 hours-DCPO : Dicumyl peroxide IZ: Izod impact value (notched, 3 mm) unit kg
・ Cm / cm ・ HDT: Heat distortion temperature load 18.6kg ・ σ _F ： Bending strength unit kg / mm ²・ σ _Y ： Bending elastic modulus unit kg / mm ² Example-2 PP resin was mixed with a modified EPR composition obtained by premixing the components shown in Table 2, and this mixture was heated at a temperature of 185 ° C. and under pressure.
A flat plate having a thickness of 3 mm was obtained by press molding at 20 kg / cm ² and used as a test piece for measuring physical properties.

The results are shown in Table 1.

The modified EPR composition was prepared by adding the components shown in Table 2 to EPR and kneading with a roll at 100 ° C. for 10 minutes.

In addition, the PP resin and the modified EPR composition are mixed at 185 ° C,
It was carried out by kneading with a kneader for 15 minutes.

The description in Table 2 was the same as the description below and in Table 1 above.

・ K1800: PP resin, manufactured by Chisso Corporation, trade name; K1800, density
0.90 MFR 20g (230 ℃ 2.16kg 10 minutes) ・ EP-57P: EPDM (EPR), Mitsubishi Petrochemical Co., Ltd., trade name; EP-5
7P, ethylene content 75% by weight, Mooney viscosity 90 (ML1-
4, 100 ℃), specific gravity 0.875 Iodine value 15 Tg ＝ -45 ℃ MI ＝ 0.2g
(190 ℃, 2.16kg 10 minutes) ・ BTR-10: 90 parts of 1,3-dicyanatobenzene and 10 parts of BMI
Weight average molecular weight of 2.6 × by heating and stirring at 130 ℃ for 7 hours
10 ³ prepolymer ・ ACAL: acetylacetone aluminum ・ BI-SH: 2-mercaptobenzimidazole Example-3 In Example-1, further, glass fiber (chopped strand, manufactured by Nippon Glass Fiber Co., Ltd., trade name; CSX-03-3167,
The length was 3 mm), but the same was applied. The results are shown in Table 3.

[Operations and Effects of the Invention] As is clear from the above detailed description and Examples-1 to 3 and the like, the polypropylene resin composition of the present invention has significantly improved impact strength, and also has strength, heat resistance and the like. It is obvious that the material is an improved one, and it is understood that it is an extremely excellent molding material in practical use.

In order to exhibit such effects, the modified EPR composition of the present invention is obtained by preliminarily mixing EPR and a cyanate ester compound and preliminarily reacting with each other, whereby the compatibility with the PP resin is improved, and It is considered that this is because the adhesiveness with the reinforcing base material is also improved.

Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display area // (C08L 23/10 23:16) (C08K 13/02 5:16 5: 3415 5:37 3:00 )

Claims (5)

[Claims] 1. A modified ethylene obtained by mixing 95 to 70 parts by weight of a polypropylene resin (a) and 5 to 30% by weight of a cyanate ester compound having at least one cyanato group in the molecule in ethylene / propylene rubber. -Impact-resistant polypropylene resin composition having improved impact resistance obtained by mixing 5 to 30 parts by weight of propylene rubber (b) 2. The modified ethylene / propylene rubber (b) comprises:
A monofunctional or polyfunctional maleimide compound is used as a modifying aid for promoting the modification of impact resistance by the cyanate ester compound, based on the cyanate ester compound.
The impact-resistant polypropylene resin composition according to claim 1, which further comprises 30% by weight or less. 3. The modified ethylene / propylene rubber (b) comprises:
A catalyst for accelerating the reaction of the cyanate ester compound is added in an amount of 0.05 to
The impact-resistant polypropylene resin composition according to claim 1 or 2, which comprises 5% by weight or 0.05 to 5% by weight of a catalyst for crosslinking the ethylene / propylene rubber. 4. As a modifying aid for promoting impact modification by the modified ethylene-propylene rubber (b), 0.05 to
The impact-resistant polypropylene resin composition according to claim 1, further comprising 5% by weight of 2-mercaptobenzimidazole. 5. A first claim in which a reinforcing material is blended.
Impact-resistant polypropylene resin composition according to item