JPH02272052A - Antistatic resin composition - Google Patents

Abstract

PURPOSE:To provide a resin composition having semi-permanent antistaticity, excellent impact resistance, etc., by compounding a specific graft copolymer with polyethylene oxide having a specified mol.wt. in specific amounts. CONSTITUTION:An antistatic resin composition comprises (A) a graft copolymer prepared by graft-copolymerizing 2-60wt.% of a cyanated vinyl monomer and 10-90wt.% of a vinylic monomer selected from aromatic vinyl monomers and (meth)acrylate esters monomers to 5-60wt.% of a rubbery polymer, (B) a vinylic polymer, (C) polyethylene oxide having an average mol.wt. of 10000-1000000 and (D) an organic sulfonic acid metal salt, preferably a nucleus-substituted benzene sulfonic acid metal salt, wherein A, B and C+D are 50-98 pts.wt., 0-50 pts.wt. and 2-15 pts.wt., respectively, based on 100 pts.wt. of the sum of A, B and C and C/D is 0.2-20.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a thermoplastic resin composition having excellent impact resistance and semi-permanent antistatic properties.

(Prior art) Polymer materials with excellent impact resistance, such as HIPS (High Impact Polystyrene) and ABS resin, are widely used due to their excellent mechanical properties and excellent surface gloss. used in the field.

However, because these resins have a high electrical resistivity value, they can cause lumps, static electricity damage, etc.
Its use was limited.

By imparting semi-permanent antistatic properties to these resins, it becomes possible to develop applications with such required characteristics.

Although there are various techniques for imparting antistatic properties to such resins, it has been relatively difficult to obtain a resin composition that has semi-permanent antistatic properties and excellent mechanical properties. As a method for imparting semi-permanent monoelectroactivity, a method of dispersing polyalkylene oxide having a low specific resistance value in a resin is practical and widely used.

JP-A-60-206865 discloses a technique for effectively lowering the surface resistance of a resin by using polyalkylene glycol and a magnesium salt of an inorganic acid in combination.

(What the invention attempts to solve! l! #J However, these resin compositions contain inorganic salts to improve their antistatic properties, which can lead to a decrease in the mechanical properties of the resin, poor appearance, etc.) This resulted in disadvantages and was not fully satisfactory in practice.

(Means for Solving the Problems) As a result of intensive studies to develop a resin composition with an excellent balance of semi-permanent antistatic properties and mechanical properties such as impact strength, the present inventors have discovered that rubber-based By blending polyethylene oxide with a molecular weight in the range of 10,000 to 1,000,000 and a metal salt of sulfonic acid to a graft copolymer obtained by graft polymerizing a specific vinyl monomer, The inventors have found that the above object can be achieved and have completed the present invention.

That is, the present invention includes: (A) 5 to 60 wt% of a rubbery polymer, 2 to 60 wt% of a vinyl cyanide monomer, an aromatic vinyl monomer, or a (meth)acrylic acid ester monomer selected from A graft copolymer obtained by polymerizing 10 to 9 Qwt% of at least one vinyl monomer, (B) a vinyl polymer, and (C) a number average molecular weight of 10,000 to 1. ooo, o
(D) a metal salt of an organic sulfonic acid, and when the total of (A), (B), and (C) is 100 parts by weight; 50 parts by weight ≦ (A) ≦ 98 parts by weight, O parts by weight ≦ (B) 550 parts by weight, 2 parts by weight ≦ (C) + (D) 515 parts by weight,
The weight ratio of (C) and (D) is 0.2≦(C)/<D)
≦20.

The present invention will be explained in detail below.

The rubbery polymer of the graft copolymer (A) used in the present invention is preferably one having a glass transition temperature of 0°C or lower, preferably -20°C or lower. Specifically, polybutadiene, styrene- Diene rubbers such as butadiene copolymer rubber, acrylonitrile-butadiene copolymer rubber,
Acrylic rubber such as polyisoprene, polychloroprene, butyl polyacrylate, ethylene-propylene rubber,
Block copolymers such as ethylene-propylene-diene ternary copolymer rubber, styrene-butadiene block copolymer rubber, styrene-isoprene block copolymer rubber, and hydrogenated products thereof can be used.

Preferably, polybutadiene, styrene-butadiene copolymer rubber, acrylonitrile-butadiene copolymer rubber,
Examples include ethylene-propylene-diene ternary copolymer rubber.

Examples of aromatic vinyl monomers include styrene, α-methylstyrene, p-methylstyrene, vinyltoluene, 0-ethylstyrene, 0,p-dichlorostyrene, and especially styrene, α-methylstyrene, etc. Styrene is preferred.

Examples of the vinyl cyanide monomer include acrylonitrile and methacrylate trile, with acrylonitrile being preferred.

(Meth)acrylic acid ester monomers include methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl acrylate, methyl acrylate, ethyl acrylate, butyl methacrylate, cyclohexyl methacrylate, benzyl methacrylate,
Phenyl methacrylate and the like are used. Particularly preferred is methyl methacrylate.

The ratio of rubbery polymer in the graft copolymer is 5 to 60
It is used in a range of 10 to 50 wt% from the viewpoint of impact resistance and workability.

The amount of vinyl monomer used in the graft copolymerization is 2 to 60 wt%, preferably 5 to 40 wt% of vinyl cyanide monomer.
t%: At least one vinyl monomer selected from aromatic vinyl monomers or (meth)acrylic acid ester monomers is used in an amount of 10 to 90 wt%, preferably 15 to 85 wt%.

Graft copolymers can be obtained by polymerizing these vinyl monomers in the presence of a rubbery polymer using known methods such as emulsion polymerization, bulk polymerization, and suspension polymerization. can.

Grafting ratio of the graft copolymer produced at this time *(I
) can be set arbitrarily, but a preferable range is 5 to 200%.

(B) As vinyl polymers, in addition to aromatic vinyl monomers, vinyl cyanide monomers, (meth)acrylic acid ester monomers; α, β such as maleic anhydride, acrylic acid, methacrylic acid, etc. - Unsaturated carboxylic acids; polymerized monomers of one or more monomers selected from maleimide monomers such as maleimide and N-phenylmaleimide; glycidyl group-containing monomers such as glycidyl methacrylate; is used. Preferred monomers include styrene, α-methylstyrene, acrylonitrile, methyl methacrylate, maleic anhydride, methacrylic acid, N-phenylmaleimide, and glycidyl methacrylate.

The polyethylene oxide (C) used in the present invention has a number average molecular weight of 10°000 to 1,000.00.
A value in the range 0 is used. Number average molecular weight is 1o, o
ooWhen using an ungrooved material, the mechanical properties of the resin (
impact resistance, rigidity) and delamination progresses, which is undesirable.
If a molecular weight exceeding 000 is used, phase separation in the resin will proceed and cause peeling, which is undesirable.More preferable ranges include numbers average molecular weights of too, 00,000
~700,000.

As the metal salt of organic sulfonic acid (D) of the present invention, a nuclear substituted benzenesulfonic acid metal salt is preferably used. Specifically, as the nuclear-substituted benzenesulfonic acid metal salt, those having the following structures are used.

Examples of metals include alkali metals such as Na, ni, t, i, etc.
A, alkaline earth metals such as Mg, and transition metals such as H2n are used. Preferred are alkali metals. A particularly preferred metal salt of sulfonic acid is sodium dodecylbenzenesulfonate.

(A) Graft copolymer, (B) Vinyl polymer, (C)
The blending composition of polyethylene oxide and (D) metal salt of organic sulfonic acid is 50 parts by weight≦(A)≦98 when the total of (A), (B), and (C) is 100 parts by weight.
parts by weight, O parts by weight≦(B) 650 parts by weight, 2 parts by weight≦(C) +<D) 615 parts by weight, (
The weight ratio of C) and (D) is 0, 2≦(C)/(D)
It is necessary that the range is ≦20.

The preferred blending amount of the graft copolymer (A) is in the range of 50 to 80 parts by weight in order to maintain mechanical properties of 11%.

(B) The preferred blending amount of the vinyl polymer is preferably in the range of 0 to 40 parts by weight from the viewpoint of the mechanical properties and moldability of the resin composition.

The amounts of (C) polyethylene oxide and (D) metal salt of organic sulfonic acid to be added are determined in consideration of the antistatic effect and the influence on mechanical properties.

If the total amount of (C) and (D) is less than 2 parts by weight, the antistatic effect will not be sufficient, and if it exceeds 15 parts by weight, the balance between impact resistance and rigidity will be compromised. A preferable range is that the total amount of (C) and <D) is in the range of 4 to 15 parts by weight, and even more preferably in the range of 6 to 12 parts by weight.

The weight ratio of (C) and (D) depends on the antistatic effect. When (C)/(D) is in the range of 0.2 to 20, the antistatic effect is high; when (C)/(D) is less than 0.2, the impact resistance is significantly lower than the antistatic effect. ,
Moreover, when it exceeds 20, the rigidity is significantly reduced compared to the antistatic effect. Preferably, it is in the range of 0.7 to 10, more preferably in the range of 1 to 5.

The method for producing the resin composition in the present invention is not particularly limited, and the resin composition can be produced by a conventional method, such as melt blending using extruder kneading.

At this time, if necessary, ordinary antistatic agents, antioxidants,
Additives such as ultraviolet absorbers, flame retardants, fillers, dyes, lubricants, and plasticizers can be added.

By adding a conductive filler to the resin composition according to the present invention, a resin composition with further improved antistatic properties can be obtained in a container.

Examples of the conductive material include carbon black, metal powder, and metal oxides (zinc oxide, iron oxide, etc.).

Furthermore, the resin composition of the present invention may be further blended with another thermoplastic polymer that is compatible with the resin composition of the present invention.
The performance as a molding resin can be improved.

(Examples) In order to explain the present invention more specifically, Examples and Comparative Examples will be described below, but these are not intended to limit the present invention. (Hereinafter, "parts" shall mean "parts by weight.") ■ Preparation of graft copolymer; a-1: Polybutadiene latex (weight average particle diameter 3
.
-1 was obtained.

a-2 = polybutadiene latex (same as a-1) 2
0 parts (solid content equivalent): 22.0 parts of acrylonitrile.
4 parts, styrene 4. HII, α-methylstyrene 52,
A monomer mixture consisting of 8 parts was subjected to emulsion polymerization to obtain graft copolymer a-2.

a-3: Polybutadiene latex (same as a-1) 4
Graft copolymer a-3 was obtained by emulsion polymerization of a monomer mixture consisting of 10 parts of acrylonitrile, 5 parts of methyl methacrylate, and 40 parts of styrene per 5 parts (in terms of solid content).
I got it.

(2) Preparation of vinyl polymer; b-1 = 20 parts of acrylonitrile and 80 parts of styrene were copolymerized to obtain polymer b-1.

b-2 = methyl methacrylate polymer.

90 parts of b-38 methyl methacrylate and 10 parts of maleic anhydride were copolymerized to obtain polymer b-3.

■Polyethylene oxide; C-12 number average molecular weight 500,000, c-2: number average molecular weight 260,000, c-3; number average molecular weight 1 1
,000,000.

C-4 number average molecular weight 1 51000, c-5: number average molecular weight 2,000,000, Example 1
~14 and Comparative Examples 1 to 8 A graft copolymer, a vinyl polymer, polyethylene oxide (abbreviated as PEO), and sodium dodecylbenzenesulfonate (hereinafter abbreviated as DBS) were blended in the composition ratios shown in Table 1, The mixture was melt-kneaded using a twin-screw extruder with a set temperature of 240°C to form pellets. Subsequently, LK specimens were molded using an injection molding machine with a cylinder temperature of 240°C and a mold temperature of 45°C, and various physical properties were measured.

The results are shown in Table 1.

In addition, in order to more clearly show the effect of a specific ratio of PEO and DBS as antistatic compounding agents in the A and B S resin compositions of the present invention, FIG. 1 shows changes in the amounts of both added. Accordingly, the relationship between physical properties and antistatic properties of an ABS resin composition is shown in a graph.

In FIG. 1, each zone A-G represents the following meaning.

A zone: Excellent balance between physical properties and antistatic effect.

B zone: A better balance between physical properties and antistatic effect.

C zone: The balance between physical properties and antistatic effect is the best.

D zone: High antistatic effect, but low rigidity and impact resistance.

E zone: Good physical properties, but low antistatic effect.

F zone: Poor balance between impact resistance and antistatic effect.

C zone: The balance between rigidity and antistatic effect is low.

As a result, it can be seen that zones A to C, which show the addition amount range specified by the present invention, are more remarkable in terms of characteristics than other zones.

・Autopsy ■Melt flow rate (MFR): Based on JIS K-7210 (.

■Impact strength (1/41200): Based on ASTM D-256.

■Tensile strength: Based on ASTM D-638.

Measurement of surface specific resistance value (Rs): An injection molded flat plate of size 40 x 40 m and thickness of 3 mm was used as a test sample, and measurement was performed using a super insulating resistance needle (MODEL 5M-10E manufactured by Toa Denpa Kogyo Co., Ltd.).

Rs after washing was measured using a test sample that was washed under running water for 10 minutes and then conditioned in a constant temperature room at 23° C. and 150% RH for 24 hours.

Rs after light irradiation was measured on the surface of the test sample irradiated for 100 hours using a sunshine weather meter (temperature: 83° C., no rain).

■Measurement of charged voltage and charged voltage decay half-life; Suctic Honest Meter (Rokunohe Shokai eA).

Using injection molding tool 1 (40 x 40 x 3 m) as a test sample, measurements were conducted under the following conditions.

Applied voltage: toKv, rotation speed: 1550 rpm5 application time: 2 minutes, measurement temperature: 23'C, measurement) richness: 50
%Fit Hl ■ Peeling of molded piece: The peeling state of the fractured surface after the tensile test (ASTM D-638) was visually determined.

O: No peeling.

Δ: Slight peeling.

X: There is considerable peeling.

(Effects of the Invention) In the present invention, by blending polyethylene glycol and a metal salt of sulfonic acid into the resin in a specific combination and in a specific amount, it has excellent antistatic properties, mechanical properties, and processing fluidity. A semi-permanent antistatic resin composition is obtained.

[Brief explanation of drawings]

FIG. 1 shows the ABS of the present invention! In the 4-fat composition, polyethylene oxide (C) and a metal salt of an organic sulfonic acid (D
) is a relationship graph showing the influence of changes in the blending ratio on the antistatic properties such as physical properties of the composition. (and 1 other person) P Mi O's Tasari Karo Seal (Weight Part) Procedural Amendment May 17, 1989

Claims (1)

[Scope of Claims] (A) 5 to 60 wt % of a rubbery polymer, 2 to 60 wt % of a vinyl cyanide monomer, and an aromatic vinyl monomer or a (meth)acrylic acid ester monomer. A graft copolymer prepared by polymerizing 10 to 90 wt% of at least one vinyl monomer, (B) a vinyl polymer, (C) a number average molecular weight of 10,000 to 1,000,00
(D) a metal salt of an organic sulfonic acid, and when the total of (A), (B), and (C) is 100 parts by weight; 50 parts by weight ≦ (A) ≦ 98 parts by weight, 0 parts by weight≦(B)≦50 parts by weight, 2 parts by weight≦(C)+(D)≦15 parts by weight, and the weight ratio of (C) and (D) is 0. An antistatic resin composition, characterized in that 2≦(C)/(D)≦20.