JP3104103B2 - Thermoplastic resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a resin molded article having excellent antistatic properties and durability, and excellent impact resistance.
The present invention relates to a thermoplastic resin composition.

[0002]

2. Description of the Related Art Thermoplastic resins such as polyolefin resins, ABS resins, and vinyl chloride resins have been widely used as materials for packaging materials and automobile parts as films, bags, and the like. Resins generally have significant drawbacks in that they have high electrical resistance, are easily charged by friction, and attract dust and the like.

[0003] In recent years, an antistatic agent has been used as a method for imparting antistatic properties to a thermoplastic resin.
There are proposed (a) a method of applying an antistatic agent to the resin surface and then drying the resin, and (b) a method of kneading the internally added antistatic agent into the resin.

In the method (a), a surfactant solution is used as an antistatic agent. However, since such an antistatic agent is easily removed by washing, a permanent antistatic agent is used. There is a disadvantage that the property cannot be imparted.

In the above method (b), glycerin fatty acid ester, sorbitan fatty acid ester, alkyldiethanolamide, sodium alkylbenzenesulfonate, quaternary salt of alkylimidazole and the like are used as the internally added antistatic agent. When these internally added antistatic agents are used, even if the antistatic agent on the surface is lost due to washing, the new antistatic agent bleeds sequentially from the inside, so that the antistatic Has the advantage of lasting for a relatively long time.

However, when such an internal addition type antistatic agent is used, it takes a long time for the antistatic property to recover after washing, and when the antistatic agent bleeds excessively, In addition to the disadvantage that tackiness occurs and dust and the like tend to adhere rather, these antistatic agents have a low molecular weight, so that they are volatilized by heat during molding at high temperatures, for example, so that they are substantially There is a disadvantage that it is necessary to add more antistatic agent than necessary amount,
It was difficult to adjust the effective amount.

In order to overcome the disadvantages of the internal addition type antistatic agent, polymethyl methacrylate in which 20 to 80 mol% of methoxy groups are modified with diethanolamine (JP-A-1-170603), alkoxypolyethylene glycol methacrylate have recently been proposed. Graft copolymer (Japanese Patent Publication No. 58-39860), a styrene-maleic anhydride copolymer which is imide-modified, and then quaternized and cationized (Japanese Patent Publication No. 29820/1989), and the terminal is carboxyl Combined copolymer of a high-molecular-weight monomer obtained by converting a terminal carboxyl group to a methacryloyl group with glycidyl methacrylate, and a quaternized cation-modified product thereof 62-121717 Polymer compounds having antistatic functional groups, such as multi-address) has been proposed. However, each of the above-mentioned polymer compounds has a drawback such that the physical properties of the resin, such as transparency and high elongation, are lowered, and the antistatic property and the durability thereof are insufficient.

In order to solve the above-mentioned drawbacks of the polymer compound having an antistatic functional group, the present inventors have proposed a polyethylene copolymer having a quaternary ammonium salt group-containing acrylamide structural unit. (Japanese Patent Application No. 2-310
85) However, even when this copolymer is used, the antistatic effect and its durability, and the strength and elongation when formed into a film are excellent, and although a considerable problem has been solved, the molded product is obtained by injection molding or the like. In such a case, mechanical properties such as impact resistance are not sufficiently satisfactory, and this is a problem when it is applied to a molded product.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in view of such conventional problems. That is, in order to impart excellent antistatic properties and mechanical properties, (A) a thermoplastic resin, especially a polyolefin resin, an ABS resin, 100 parts by weight of a polyamide resin,
The composition is characterized by comprising a composition comprising (B) 3 to 40 parts by weight of a thermoplastic elastomer and (C) 3 to 30 parts by weight of the following acrylamide copolymer.

That is, the formula:

Embedded image 65 to 99 mol% of an ethylene structural unit represented by the following general formula:

Embedded image (Wherein R ¹ represents an alkyl group having 1 to 4 carbon atoms) 0 to 15 mol% of an acrylate structural unit represented by the following general formula:

Embedded image (Wherein, R ² is an alkylene group having 2 to 8 carbon atoms, R ³ and R ⁴ are alkyl groups having 1 to 4 carbon atoms, R ⁵ is an alkyl group having 1 to 12 carbon atoms, and 6 to 12 carbon atoms. An arylalkyl group or an alicyclic alkyl group having 6 to 12 carbon atoms, X
Is a halogen atom, CH ₃ OSO ₃ or C ₂ H ₅ OSO
Acrylamide structural units 1-3 represented by ₃ )
An acrylamide copolymer having a weight-average molecular weight of 1,000 to 50,000 and consisting of 5 mol% and arranged linearly and irregularly.

The thermoplastic resin used in the present invention includes polyolefin resin, polyvinyl chloride, polystyrene, ABS resin, polyamide resin, polyester resin,
Polycarbonate resin, modified polyphenylene ether and the like can be exemplified. Among them, preferred resins are polyolefin resin, ABS resin and polyamide resin.

Here, the polyolefin resin includes polyolefins, ethylene-vinyl ester copolymers, ethylene-acryl ester copolymers and the like, and also includes blends of these various polyolefins and copolymers.

More specifically, the above polyolefins are
High-density polyethylene, medium-density polyethylene, low-density polyethylene, polypropylene, polybutene, poly-4-methylpentene-1, copolymers of ethylene and α-olefins, among such polyolefin resins,
High-density polyethylene, medium-density polyethylene, low-density polyethylene, and polypropylene are preferable, and the number average molecular weight thereof is usually 5,000 to 500,000, preferably 10,000 to 200,000.
Fits.

The kind of the ABS resin is not particularly limited, and a resin obtained by a graft method or a polymer blend method can be used. In addition, AS resin (acrylonitrile-
Styrene resin), AES resin (acrylonitrile-EP)
DM-styrene resin) and the like can be used, but an ABS resin is preferable.

The polyamide resin is not particularly limited, and various types can be used, and any of aliphatic and aromatic polyamide resins may be used. Although the molecular weight is not particularly limited, the number average molecular weight is 4,000 to 5 in consideration of the moldability and physical properties of the obtained composition.
000, preferably 5,000 to 30,000 are suitable.

Such a polyamide resin can be produced by various known methods. For example, it can be produced by ring-closing (co) polymerization or (co) polycondensation of a lactam having three or more rings, a polymerizable ω-amino acid, a dibasic acid and a diamine, or the like.

Various polyamide resins can be used as the above-mentioned polyamide resin.
Nylon 6, 6; Nylon 6, 10; Nylon 11, Nylon 12, Nylon 6, 12; Aliphatic polyamide such as Nylon 4, 6, Nylon 6/6; Nylon 6/6, 10; Nylon 6/6 And aromatic polyamides such as polyhexamethylene diamine terephthalamide; polyhexamethylene diamine isophthalamide; and xylene group-containing polyamide. Further, polyester amide, polyester ether amide and the like can be mentioned. Preferred polyamide resins are nylon 6; nylon 6,6.
It is.

The thermoplastic elastomer used in the present invention includes polyolefin elastomer, polystyrene elastomer, polyamide elastomer, polyester elastomer, polyurethane elastomer,
And vinyl chloride elastomers.

Preferred elastomers are polyolefin elastomers, polystyrene elastomers,
It is a polyamide elastomer.

Specific examples of the polyolefin-based elastomer include ethylene-propylene rubber (EPR), ethylene-propylene-diene copolymer (EPDM), ethylene vinyl acetate copolymer (EVA), butyl rubber, butadiene rubber, and low-crystalline ethylene- Examples include a propylene copolymer or a propylene-butene copolymer, and a blend of polypropylene and an ethylene-propylene rubber.

Among such polyolefin-based elastomers, preferred are polypropylene, ethylene-propylene rubber and ethylene-propylene-diene copolymer (EPDM).

The polystyrene-based elastomer is a block polymer having a hard segment having polystyrene and a soft segment having polybutadiene, polyisoprene or polyolefin. As specific examples, styrene-butadiene-styrene (SBS) copolymer, styrene-isoprene-styrene (SIS) copolymer, and S
Examples include SEBS obtained by hydrogenating BS and SEPS obtained by hydrogenating SIS.

The polyamide-based elastomer is a block polymer using polyamide as a hard segment and polyether or polyester as a soft segment. For example, polyether ester amide,
Polyesteramides can be used.

The acrylamide copolymer used in the component [C] of the present invention has the formula:

Embedded image 65 to 99 mol% of an ethylene structural unit represented by the following general formula:

Embedded image (Wherein R ¹ represents an alkyl group having 1 to 4 carbon atoms) 0 to 15 mol% of an acrylate structural unit represented by the following general formula:

Embedded image (Wherein, R ² is an alkylene group having 2 to 8 carbon atoms, R ³ and R ⁴ are alkyl groups having 1 to 4 carbon atoms, R ⁵ is an alkyl group having 1 to 12 carbon atoms, and 6 to 12 carbon atoms. An arylalkyl group or an alicyclic alkyl group having 6 to 12 carbon atoms, X
Is a halogen atom, CH ₃ OSO ₃ or C ₂ H ₅ OSO
Acrylamide structural units 1-3 represented by ₃ )
It is an acrylamide copolymer having a weight average molecular weight of 1,000 to 50,000 and consisting of 5 mol% and arranged linearly and irregularly.

The formula in the acrylamide copolymer is as follows:

Embedded image Is 65 to 99 mol%. When the proportion of the ethylene structural unit is less than 65 mol%, the softening point of the acrylamide copolymer is lowered, and when the acrylamide copolymer is blended with a thermoplastic resin, tackiness or stickiness due to tackiness or stickiness is generated. If the amount exceeds mol%, the antistatic property of the acrylamide copolymer becomes too small. In the present invention, the proportion of the ethylene structural unit is particularly preferably from 85 to 97 mol% from the viewpoint of the balance between the softening point and the antistatic property.

The general formula in the acrylamide copolymer is as follows:

Embedded image (Wherein R ¹ is the same as described above). The proportion of the acrylate structural unit is from 0 to 15 mol%. If the proportion of the acrylate structural unit exceeds 15 mol%, the softening point of the acrylamide-based copolymer becomes low, and when the acrylamide-based copolymer is mixed with a thermoplastic resin, tackiness due to tack or stickiness occurs. In the present invention, when the acrylate structural unit is contained, the antistatic property is preferably improved. In the present invention, the proportion of the acrylate structural unit is from 1 to 15 mol%, especially from 3 to 7 from the viewpoint of the balance between the softening point and the antistatic property.
Preferably it is mol%.

In the acrylate structural unit, R ¹
Is an alkyl group having 1 to 4 carbon atoms. Specific examples of such R ¹ include a methyl group, an ethyl group, an n-propyl group, i
-Propyl group, n-butyl group and i-butyl group, and these groups may be mixed in one molecule. In these groups, a methyl group and an ethyl group are particularly preferable for maintaining a softening point.

The general formula in the acrylamide copolymer is as follows:

Embedded image (Wherein R ² , R ³ , R ⁴ and R ⁵ are the same as described above), and the proportion of the acrylamide structural unit is 1 to 35 mol%. When the proportion of the acrylamide structural unit is less than 1 mol%, the antistatic property is too small, and when it exceeds 35 mol%, when the acrylamide copolymer is blended with a thermoplastic resin, It becomes hygroscopic. In the present invention, the proportion of the acrylamide structural unit is particularly preferably 3 to 15 mol% from the viewpoint of balance with antistatic properties and hygroscopicity.

In the acrylamide structural unit, R
² is an alkylene group having 2 to 8 carbon atoms. Specific examples of such R ² include, for example, an ethylene group, a propylene group,
Hexamethylene group, neopentylene group and the like,
These groups may be mixed in one molecule. Among these groups, an ethylene group and a propylene group are preferable, and a propylene group is particularly preferable, from the viewpoint of easiness of production and economy.

The above R ³ and R ⁴ each have 1 to 1 carbon atoms.
4 alkyl group. Specific examples of such R ³ and R ⁴ include a methyl group, an ethyl group, a propyl group, and a butyl group, and these groups may be present in one molecule. Among these groups, a methyl group and an ethyl group are preferred from the viewpoint of imparting antistatic properties.

R ⁵ is an alkyl group having 1 to 12 carbon atoms;
An arylalkyl group having 6 to 12 carbon atoms or 6 to 12 carbon atoms
12 alicyclic alkyl groups. Specific examples of such ^{R 5,} for example a methyl group, an ethyl group, n- propyl group, i
-Propyl group, n-butyl group, sec-butyl group, n-
Alkyl groups such as octyl group and n-lauryl group; arylalkyl groups such as benzyl group and 4-methylbenzyl group; alicyclic alkyl groups such as cyclohexyl group and methylcyclohexyl group; They may be mixed. R ⁵ is preferably a linear alkyl group or an arylalkyl group from the viewpoint of heat resistance, and is preferably a lower alkyl group from the viewpoint of imparting antistatic properties. Particularly preferred R ⁵ includes a methyl group and an ethyl group.

X is, for example, a halogen atom such as Cl, Br or I, CH ₃ OSO ₃ or C ₂ H ₅ OSO ₃ , which may be present in one molecule. In addition,
Among them, Cl, CH ₃ OS
O ₃ and C ₂ H ₅ OSO ₃ are preferred.

The weight average molecular weight of the acrylamide copolymer is 1,000 to 50,000. The weight average molecular weight referred to here is a weight average molecular weight in terms of polystyrene measured by gel permeation chromatography, and is ultra-high temperature GPC (Kinukawa, Journal of Polymers,
Vol. 44, No. 2, pp. 139-141 (1987)). This molecular weight is 1,000
If the molecular weight is less than the above, the molecular weight becomes too small, and the compound may be mixed with the thermoplastic resin and volatilized when heated. Worse. The preferred weight average molecular weight is from 3,000 to 33,000.

The acrylamide copolymer used in the present invention is, for example, an ethylene-acrylate copolymer obtained by copolymerizing ethylene and an acrylate by a high-pressure polymerization method, for example, as described in JP-A-60-79008. According to the method described in the official gazette, the resulting ethylene-acrylic acid ester-acrylic acid copolymer is amidated with N, N-dialkylaminoalkylamine by thermal degradation to a desired molecular weight at the same time as hydrolysis. It is obtained by cation modification with a quaternizing agent.

The mixing ratio of the components (A) to (C) is 3 to 40 parts by weight of the component (B) and 3 to 30 parts by weight of the component (C) based on 100 parts by weight of the component (A).

When the amount of the component (B) is less than 3 parts by weight, the effect of improving the impact resistance is small, and when it exceeds 40 parts by weight, the effect of improving the impact resistance is sufficient, but other physical properties such as heat deformation temperature Lower. The particularly preferred range of the component (B) is from 5 to
20 parts by weight.

When the amount of the component (C) is less than 3 parts by weight, the antistatic property is insufficient, and when it exceeds 30 parts by weight, it is uneconomical and lowers the heat distortion temperature. A particularly preferred range for component (C) is 5 to 20 parts by weight.

The method of compounding the above components (A) to (C) is as follows.

The components (A) to (C) are kneaded under heat and melt using a single-screw or twin-screw extruder, a pressure kneader, or the like to obtain a composition. Alternatively, two components out of the components (A) to (C) may be mixed in advance to form a master batch, and then the other one component may be mixed and further kneaded or directly applied to a molding machine such as an injection molding machine.

In the thermoplastic resin of the present invention, the component (B) functions to relieve stress such as impact and to improve physical properties such as impact resistance.
Further, the component (C) exhibits an antistatic property.

[0041]

EXAMPLES Preparation of an acrylamide copolymer is carried out as follows.

The ethylene-alkyl acrylate-acrylic acid copolymer produced by the thermal degradation method is reacted with N, N-dialkylaminoalkylamine to amidate and then quaternized to obtain a compound represented by the formula:

Embedded image An ethylene structural unit represented by the general formula:

Embedded image An acrylate structural unit represented by the general formula:

Embedded image To obtain an acrylamide copolymer comprising an acrylamide structural unit represented by the formula:

A specific production example is shown below.

<Production Example 1> 400 ml of xylene, ethylene-ethyl acrylate-acrylic acid copolymer (A) was placed in a 1-liter four-necked flask equipped with a thermometer, a stirrer, a dropping funnel and a Dean-Stark separator. 150 g of ethylene / ethyl acrylate / acrylic acid = 93/3/4) and 1.0 g of paratoluenesulfonic acid were charged.

Next, 21.1 g of N, N-dimethylaminopropylamine was charged and the mixture was heated at 140 ° C. using an oil bath.
, And the generated water was continuously removed by azeotropy with xylene. Further, the reaction was carried out at 140 ° C. for 17 hours, and the amidation reaction was continued until no water was generated and no azeotropy of water was observed. .

458 g of the obtained reaction product was cooled to 80 ° C., and methyl iodide 2 was added to the reaction mixture from a dropping funnel.
8.7 g was gradually added dropwise over 1 hour. During this time, heat generation was observed, but the reaction temperature was reduced to 90 ° C. by cooling.
Maintained. After completion of the dropwise addition, an aging reaction was performed at 100 ° C. for 4 hours. The reaction product thus obtained was poured into a large amount of methanol, and the generated precipitate was recovered and dried to obtain an acrylamide copolymer. When the weight average molecular weight of this acrylamide copolymer was measured,
00.

<Production Examples 2 to 9> Similarly to Production Example 1, acrylamide copolymers shown in Production Examples 2 to 9 in Table 1 were prepared according to the method described in Japanese Patent Application No. 2-31082. Production Examples 2 to 9 differ from Production Example 1 in the following points.

In Production Examples 8 and 9, R ¹ in the ethylene-ethyl acrylate-acrylic acid copolymer of the raw material copolymer was an n-propyl group and an n-butyl group, respectively. An ethylene-acrylic acid copolymer was used as the polymer. In Production Examples 4 and 8, N, N-dimethylaminoethylamine was used as the aminating agent, in Production Example 6, N, N-dimethylaminoneopentylamine was used as the aminating agent, and in Production Example 7, N, N-dimethylaminoneopentylamine was used as the aminating agent. In Example 9, N, N-diethylaminoethylamine was used as an aminating agent. Production Examples 2, 5, 6
In Examples 8 and 9, diethyl sulfate was used as a quaternizing agent, in Production Examples 4 and 9, benzyl chloride was used as a quaternizing agent, and in Production Example 3, p-methylbenzyl chloride was used as a quaternizing agent.

Table 1 shows that R ^{1 to} R ⁵ and X ⁻ in each of the structural units of the acrylamide copolymers of Production Examples 1 to 9, the amounts of the ethylene structural units, the amounts of the acrylate structural units, and the amounts of the acrylamide structural units. Was shown in the molar ratio.

[0050]

[Table 1]

Using the acrylamide copolymer obtained above as the component (C), a thermoplastic resin was obtained and evaluated. The example is shown below.

<Examples 1 to 9> A twin-screw extruder was used to obtain 30 parts by weight of the acrylamide copolymer obtained in Production Examples 1 to 9 and 70 parts by weight of the thermoplastic resin (component (A)) shown in Table 2. (KRC Kneader, manufactured by Kurimoto Iron Works) was melted and kneaded to obtain a master batch of component (C) 30%.

Next, a predetermined amount of the thermoplastic resin (component (A)), the thermoplastic elastomer (component (B)) and the masterbatch described in Table 2 were blended, and an injection molding machine (Hi
pershot 3000 (manufactured by Niigata Iron Works) to obtain a molded product.

However, * 1 to * 8 in the table are as shown below.

* 1 Polypropylene Tokuyama Soda ME-23
0 * 2 High density polyethylene Mitsubishi Kasei Mitsubishi Polyethylene HD JV070S * 3 ABS resin Ube Psycon Psycholac T * 4 Polyamide 66 Asahi Kasei Leona
1300S * 5 EPR Nippon Synthetic Rubber EPO
2P * 6 SEBS Shell Chemical Clayton G-1567 * 7 Polyetheresteramide Toray Pebax 5533SN00 * 8 EPDM Mitsui Petrochemical EPT
3095 Using the molded article obtained as described above, the antistatic property and its durability, and the Izod impact strength were examined.

The evaluation of the antistatic property and its durability was performed by measuring the surface resistivity.

The method of measuring the surface resistivity is as follows.

After leaving the molded test piece under the conditions of 20 ° C. and 30% RH (relative humidity) or 20 ° C. and 60% RH for 24 hours, a super-insulating system R-503 manufactured by Kawaguchi Electric Works, Ltd. was used. The surface specific resistance was measured.

The durability of the antistatic property was evaluated as follows.

After the molded test piece was aged in an oven at 40 ° C. for 14 days, the surface was thoroughly washed with an aqueous solution of mama lemon (manufactured by Lion Corporation) as a detergent.
Rinse thoroughly with deionized water, then at 20 ° C, 60% R
It was left for 24 hours in an atmosphere of H, and the surface resistivity was measured by the method described above.

The impact resistance was evaluated by measuring Izod impact strength.

As for the Izod impact strength, Izod impact value was measured according to JIS K-7110.

In order to examine the contribution of the component (B) to the impact resistance, the same evaluation was performed without using the component (B).

<Comparative Example 1> The same procedure as in Example 1 was carried out without using EPR.

<Comparative Example 2> The same procedure as in Example 3 was carried out without using SEBS.

<Comparative Example 3> The same procedure as in Example 4 was carried out without using polyetheresteramide.

[0067]

[Table 2]

As is clear from the surface resistivity values shown in Table 2, all of the thermoplastic resin compositions of the present invention show excellent antistatic properties, and these antistatic properties hardly deteriorate even by washing.

As for the impact resistance, as apparent from comparison of the Izod impact values of Comparative Example 1 and Example 1, Comparative Example 2 and Example 3, and Comparative Example 3 and Example 4, the component (B The impact resistance is greatly improved by the addition of).

[0070]

According to the thermoplastic resin composition of the present invention, a resin molded product excellent in antistatic effect, its durability and impact resistance can be obtained.

Continuation of the front page (51) Int.Cl. ⁷ Identification code FI (C08L 101/00 21:00 23:08) (56) References JP-A-4-198308 (JP, A) JP-A-63-54467 ( JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08L 1/00-101/16 C08F 20/60 C08F 220/60

Claims (4)

(57) [Claims] 1. A resin composition comprising (B) 3 to 40 parts by weight of a thermoplastic elastomer, and (C) 3 to 30 parts by weight of an acrylamide copolymer described below with respect to 100 parts by weight of a thermoplastic resin (A). Formula: 65 to 99 mol% of an ethylene structural unit represented by the following general formula: (Wherein R ¹ represents an alkyl group having 1 to 4 carbon atoms) 0 to 15 mol% of an acrylate structural unit represented by the following general formula: (Wherein, R ² is an alkylene group having 2 to 8 carbon atoms, R ³ and R ⁴ are alkyl groups having 1 to 4 carbon atoms, R ⁵ is an alkyl group having 1 to 12 carbon atoms, and 6 to 12 carbon atoms. An arylalkyl group or an alicyclic alkyl group having 6 to 12 carbon atoms, X
Is a halogen atom, CH ₃ OSO ₃ or C ₂ H ₅ OSO
Acrylamide structural units 1-3 represented by ₃ )
An acrylamide copolymer having a weight-average molecular weight of 1,000 to 50,000 and consisting of 5 mol% and arranged linearly and irregularly. 2. The thermoplastic resin composition according to claim 1, wherein the thermoplastic resin is a polyolefin. 3. The method according to claim 1, wherein the thermoplastic resin is AB.
A thermoplastic resin composition which is an S resin. 4. The thermoplastic resin composition according to claim 1, wherein the thermoplastic resin is a polyamide resin.