JPH0641393A - Resin pellet having high nitrile content - Google Patents

Abstract

PURPOSE:To provide a resin pellet having a high nitrile content and capable of providing moldings improved in scratch resistance without impairing transparency, etc. CONSTITUTION:The pellet is obtained by substantially uniformly attaching a higher fatty acid having an amount corresponding to 0.01-0.1 pts.wt. based on 100 pts.wt. pellet onto the surface of pellet of a rubber reinforced vinyl cyanide based graft copolymer and/or vinyl cyanide based copolymer having 40-85wt.% vinyl cyanide unit content.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high nitrile resin pellet, and more specifically, a high nitrile rubber-reinforced vinyl cyanide graft copolymer (hereinafter abbreviated as "high nitrile ABS resin") and And / or a high nitrile vinyl cyanide copolymer (hereinafter abbreviated as “high nitrile AS resin”), and particularly relates to a high nitrile resin resin pellet which gives a molded article with improved scratch resistance. .

[0002]

2. Description of the Related Art High nitrile ABS resin and high nitrile AS
Resins are excellent in transparency, rigidity, chemical resistance, dimensional stability, gas barrier properties, etc., and are therefore used in molded products such as household electrical appliances, automobile parts, and sundries.

[0003]

However, molded articles made of the above resins have a problem that they are easily scratched while having hard properties. The present invention has been made in view of the above circumstances, and an object thereof is to provide a high nitrile resin pellet which gives a molded article having improved scratch resistance without impairing transparency and the like.

[0004]

That is, the gist of the present invention is to provide a rubber-reinforced vinyl cyanide-based graft copolymer and / or vinyl cyanide-based copolymer having a vinyl cyanide unit content of 40 to 85% by weight. A high nitrile resin pellet characterized in that an amount of 0.01 to 0.1 part by weight of a higher fatty acid corresponding to 100 parts by weight of the pellet is adhered substantially uniformly to the surface of the polymer pellet.

The present invention will be described in detail below. First, the high nitrile ABS resin targeted by the present invention will be described. In the present invention, the high nitrile ABS resin is a copolymer of other vinyl monomers which can be copolymerized with rubber cyanide, vinyl cyanide monomer, aromatic vinyl monomer and other vinyl cyanide monomers. And the content of vinyl cyanide units is 4
It refers to a copolymer that is 0 to 85% by weight.

As the above rubber elastic body, conjugated diene,
In particular, butadiene copolymers such as polybutadiene, butadiene-styrene copolymers, and butadiene-acrylonitrile copolymers are mentioned. Further, as other rubber elastic body, acrylic rubber, for example, butyl acrylate-acrylonitrile copolymer, ethylene propylene rubber, particularly ethylene-known as EPDM-
A propylene-non-conjugated diene copolymer is mentioned.

Specific examples of the above vinyl cyanide monomer include acrylonitrile, methacrylonitrile,
Examples thereof include glutaronitrile, methyleneglutaronitrile, fumaronitrile and α-chloroacrylonitrile. These may be a mixture.

Examples of the aromatic vinyl monomer include styrene, nucleus- and / or side-chain-substituted styrene, vinylnaphthalene, nucleus- and / or side-chain-substituted vinylnaphthalene, and the like. And as a substituent, a lower alkyl group and a halogen (especially chlorine) atom are typical. Therefore, specific examples of the aromatic vinyl monomer include α-methylstyrene, vinyltoluene, chlorostyrenes, vinylnaphthalene, and the like, in addition to styrene. These may be a mixture.

The high nitrile ABS resin used in the present invention includes those obtained by copolymerizing a vinyl monomer in addition to the above aromatic vinyl monomer. Examples of such vinyl monomers include (meth) acrylic acid esters (especially lower alkyl esters) such as methyl methacrylate and methyl acrylate, and small amounts of divinylbenzene, ethyl glycol di (meth) acrylate and the like. The cross-linkable monomer of is mentioned. In addition, the above-mentioned "(meth) acrylic acid" is meant to include both acrylic acid and methacrylic acid, and the same applies to the "(meth) acrylate" description regarding its acid component.

The nitrile ABS resin is produced by any method capable of polymerizing a vinyl monomer such as an aromatic vinyl monomer and a vinyl cyanide monomer in the presence of a rubber elastic body, either temporarily or stepwise. be able to. Therefore, depending on the type or state of a given rubber elastic body, the suspension polymerization method,
An emulsion polymerization method, a continuous bulk polymerization method, and other methods can be appropriately selected and used. Specifically, for example, when the rubber elastic body is obtained as an emulsion, the monomers may be emulsion polymerized in the emulsion. As the product, particularly when the rubber elastic body has an ethylenically unsaturated bond, at least a part of the “stem” polymer composed of a monomer such as aromatic vinyl is added to the “stem” polymer composed of the rubber elastic body. In many cases, it is a graft polymer that is physically bonded.

The present invention is directed to a high nitrile ABS resin in which the content of vinyl cyanide units in the matrix resin is 40 to 85% by weight among the above nitrile ABS resins. The preferred content of vinyl cyanide units is 5
It is 0 to 80% by weight. The content of the rubber elastic body in the high nitrile ABS resin is preferably 5 to 30% by weight. When the content of vinyl cyanide unit is less than the above range, the chemical resistance of the obtained molded product is not sufficient, and when it is more than the above range, the moldability becomes poor and the burn easily occurs during molding. Become. High nitrile ABS
The content of vinyl cyanide units in the resin does not include those derived from a rubber elastic body (if any).

Next, the high nitrile A which is the object of the present invention
The S resin will be described. In the present invention, the high nitrile AS resin is a copolymer of vinyl cyanide monomers and other vinyl monomers that can be copolymerized with vinyl cyanide monomers such as aromatic vinyl monomers. A copolymer having a vinyl chloride unit content of 40 to 85% by weight. Examples of other vinyl monomers such as the above vinyl cyanide monomer and aromatic vinyl monomer include the same monomers as those in the above-mentioned high nitrile ABS resin. Also in the case of the high nitrile AS resin, a small amount of a crosslinkable monomer may be copolymerized in addition to the above-mentioned essential components, and specific examples of such a comonomer are the same as those described above for the high nitrile ABS resin. Is the same as.

According to the present invention, the content of vinyl cyanide unit in the nitrile AS resin is 40 to 85% by weight.
Is intended for. The preferred content of vinyl cyanide units is 50-80% by weight. Therefore, the content of other vinyl monomers such as aromatic vinyl units in the high nitrile AS resin is 15 to 60% by weight, preferably 20 to 50% by weight. When the content of vinyl cyanide unit is less than the above range, the chemical resistance of the obtained molded product is not sufficient, and when it is more than the above range, the moldability becomes poor and the burn easily occurs during molding. Become.

Next, the high nitrile resin pellet of the present invention will be described. High nitrile resin pellets of the present invention,
It is made of the above-mentioned high nitrile ABS resin and / or high nitrile AS resin, and a predetermined amount of higher fatty acid is adhered to its surface substantially uniformly.

Specific examples of the higher fatty acid used in the present invention include fatty acids described in (a) and (b) below. (A) higher saturated fatty acid having 8 to 31 carbon atoms such as caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid, and montanic acid (b) undecylenic acid, oleic acid, erucic acid Higher unsaturated fatty acid having 8 to 31 carbon atoms such as acid and linoleic acid In the present invention, higher saturated fatty acid having 10 to 31 carbon atoms, more preferably 15 to 22 carbon atoms is used.

The above resin pellets are made of high nitrile ABS.
If necessary, additives and colorants may be mixed with the resin and / or high nitrile AS resin, then melt-kneaded and pelletized with a pelletizer, and the higher fatty acid may be adhered to the surface substantially uniformly. Can be obtained.

A general blender, a Henschel mixer or the like is used for mixing the respective components, and the melt-kneading is performed by
Commonly used single screw extruder, twin screw extruder, kneader,
A Beverly mixer, roll, etc. can be used. Further, the method of attaching the higher fatty acid is not particularly limited, and may be a normal blender, a batch type using a Henschel mixer, or a continuous type using an air blender. Then, the resin pellet can be appropriately wetted with a liquid auxiliary agent before the higher fatty acid is attached. Suitable liquid auxiliaries include polyethylene glycol, mineral oil and the like.

The amount of the higher fatty acid attached to the surface of the resin pellet is 0.01 to 100 parts by weight of the resin pellet.
The amount should be equivalent to 0.1 part by weight. When the amount of the higher fatty acid attached is less than the above range, it has no effect on the scratch resistance as the object of the present invention, and moreover, the molten resin adheres to the screw in the measuring step of injection molding, so that the molten resin The weighing time is unstable. On the other hand, when the amount of the higher fatty acid attached exceeds the above range, the slipperiness is too high and it becomes difficult to measure the resin within a certain time. The high nitrile resin pellets of the present invention provide various molded products with improved scratch resistance, and as a processing method thereof, various processing methods such as an injection molding method, an extrusion molding method and a press processing method are used depending on the purpose. Can be adopted.

[0019]

EXAMPLES The present invention will be described in more detail with reference to examples below, but the present invention is not limited to the following examples as long as the gist thereof is not exceeded. In addition, the physical property measurement is
The test pieces required for the measurements (2) to (6) were prepared by injection molding by the following method.

(1) Tensile strength (Kg / cm ² ) conforming to JIS K7113 (2) Izod impact strength (Kg · cm ² / cm ² ) conforming to JIS K7110 1/8 "Notch (3) Heat distortion temperature (° C) According to JIS K7207, a test piece with a thickness of 6.4 mm, a width of 12.7 mm and a length of 127 mm was used without annealing. , Bending stress is 18.6k
The measurement was performed at g / cm ² . (4) Melt flow rate (MFR) (g / 10 minutes) According to JIS K7210 As the measurement conditions, a resin temperature of 220 ° C. and a load of 10 kg were adopted. (5) Haze (cloudiness value) Based on JIS K7105 It measured with the injection molding board of thickness 2.5mm. The smaller the haze value, the better the transparency.

(6) Evaluation of Scratch Resistance Using a surface property measuring device HEIDON-14D (manufactured by Shinto Kagaku Co., Ltd.), a scratch test was conducted on an injection-molded flat plate having a thickness of 2.5 mm in the following manner. . Then, a diamond weight having a weight tip R of 0.01 mm and an angle of 90 ° was used. First, set the flat plate on a horizontal table, put a diamond weight vertically, and put 200 gr or 3 on it.
Place a weight of 00gr on the table with a flat plate
Move at a speed of 00 mm / min. Then, the depth (μm) of the scratch is measured with a universal surface profiler (manufactured by Kosaka Laboratory).

(7) Moldability In the measuring process of the injection molding machine, the state of the resin fed and measured by the rotation of the screw was evaluated in the following three stages. ◯: A state where the resin measurement is stable and there is no problem in moldability. Δ: A state where the resin measurement is unstable and molding is difficult within a certain period of time. X: Resin adhered to a screw or excessively slippery. Is not sent and cannot be weighed

[0023]

【Example】

Examples 1 to 4 Butylated hydroxytoluene (BHT) as an antioxidant was added to each bead of a high-nitrile AS resin having an acrylonitrile (AN) content shown in Table 1 obtained by a suspension polymerization method.
0.1 part by weight was mixed with a drum mixer and melt-kneaded at 220 ° C. with a single-screw extruder to obtain pellets of Examples 1 to 3. The amount of stearic acid shown in Table 1 was added to 100 parts by weight of each of the above pellets and mixed with a drum mixer to uniformly attach stearic acid to the surface of the pellets.
Next, the above pellets were injection-molded and the performance was evaluated. The results are shown in Table 1.

Further, 0.1 part by weight of butylated hydroxytoluene (BHT) as an antioxidant was mixed with a high nitrile ABS resin composition having an AN content shown in Table 1 in a drum mixer to prepare a twin screw extruder. Were melt-kneaded at 220 ° C. to obtain pellets of Example 4. The amount of stearic acid shown in Table 1 was added to 100 parts by weight of the above pellets and mixed by a drum mixer to uniformly attach the stearic acid to the surface of the pellets. Next, each of the above pellets was injection-molded and the performance was evaluated. The results are shown in Table 1.

[0025]

Table 1 Example 1 2 3 4 ────────────────────────────── Acrylonitrile (% by weight) 55 55 75 55 ^* Styrene (% by weight) 45 45 25 45 ^* Rubber content (% by weight) − − − 9 Stearic acid (parts by weight) 0.03 0.09 0.03 0.03 Tensile strength (Kg / cm ² ) 841 837 870 700 Izod impact strength 1.3 1.3 1.3 5.5 (Kg ・ cm ² / cm ² ) Heat distortion temperature (℃) 95 95 93 95 Melt flow rate (g / 10 minutes) 23 24 13 9 Haze (%) 6 6 6 12 Scratch depth (μm) 200g Load 0 0 0 0.5 300 g load 0 0 0 3.5 Moldability ○ ○ ○ ○ ────────────────────────────── *: Rubber (butadiene ) Excluding AN content of matrix

Comparative Examples 1 to 4 0.1 part by weight of butylated hydroxytoluene (BHT) as an antioxidant was added to each bead of the high nitrile AS resin having an AN content shown in Table 2 obtained by the suspension polymerization method. The mixture was mixed in a mold mixer and melt-kneaded at 220 ° C. in a single screw extruder to obtain pellets of Comparative Examples 1 to 4. Each of the above pellets 10
The amount of each lubricant described in Table 2 was added to 0 part by weight and mixed with a drum mixer to uniformly attach each lubricant to the pellet surface (however, the pellets of Comparative Example 1 were added with no lubricant). ). Next, the above pellets were injection-molded and the performance was evaluated. The results are shown in Table 2.

[0027]

[Table 2] Comparative Example 1 2 3 4 ────────────────────────────── Acrylonitrile (% by weight) 55 55 55 55 Styrene (Wt%) 45 45 45 45 Rubber content (wt%) − − − − Stearic acid (parts by weight) − 0.15 − − Ethylenebisstearic acid amide (parts by weight) − − 0.03 − Magnesium stearate (parts by weight) − − − 0.03 Tensile strength (Kg / cm ² ) 840 831 837 839 Izod impact strength 1.3 1.3 1.3 1.3 (Kg · cm ² / cm ² ) Heat distortion temperature (℃) 95 94 95 95 Melt flow rate (g / 10 minutes) 23 24 23 23 Haze (%) 5 8 25 32 Scratch depth (μm) 200 g load 0 0 0 0 300 g load 3.5 0 0 0 Formability △ × ○ ○ ────────────── ─────────────────

Comparative Examples 5 to 7 In the high nitrile ABS resin composition having an AN content shown in Table 3, butylated hydroxytoluene (BH) was used as an antioxidant.
T) 0.1 part by weight was mixed with a drum mixer and melt-kneaded at 220 ° C. with a twin-screw extruder to obtain pellets of Comparative Example 5. The above pellets were injection-molded and the performance was evaluated. The results are shown in Table 3.

Further, butylated hydroxytoluene (BHT) 0.1 was added as an antioxidant to each bead of the high nitrile AS resin having an AN content shown in Table 3 obtained by the suspension polymerization method.
Parts by weight are mixed by a drum type mixer and 22 by a single screw extruder.
Melt kneading at 0 ° C. to obtain pellets of Comparative Examples 6 and 7.
The pellets of Comparative Example 6 described above were injection molded and the performance was evaluated. The results are shown in Table 3. To 100 parts by weight of the pellet of Comparative Example 7 described above, the amount of stearic acid shown in Table 3 was added and mixed with a drum mixer to allow the stearic acid to uniformly adhere to the surface of the pellet, followed by injection molding. The performance was evaluated with the results shown in Table 3.

[0030]

[Table 3] Comparative Example 5 6 7 ───────────────────────── Acrylonitrile (wt%) 55 ^* 75 26 Styrene (wt%) 45 ^* 25 74 Rubber content (wt%) 9 − − Stearic acid (parts by weight) − − 0.03 Tensile strength (Kg / cm ² ) 702 868 740 Izod impact strength 5.5 1.3 1.4 (Kg · cm ² / cm ² ) Heat distortion temperature (℃) 95 93 91 Melt flow rate (g / 10 min) 9 13 25 Haze (%) 11 5 2 Scratch depth (μm) 200 g load 3.0 0 2.0 300 g load 7.0 0.5 7.5 Formability △ △ ○ ─── ────────────────────── *: AN content of matrix excluding rubber (butadiene)

[0031]

According to the present invention described above, there is provided a high nitrile resin pellet which gives a molded article having improved scratch resistance without impairing transparency and the like. And, the high nitrile resin pellets of the present invention are household electric appliances,
It can be suitably used for molded articles such as automobile parts and sundries.

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[Procedure amendment]

[Submission date] April 15, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0020

[Correction method] Change

[Correction content]

(1) Tensile strength (Kg / cm ² ) conforming to JIS K7113 (2) Izod impact strength (Kg · cm / cm) conforming to JIS K7110 1/8 "Notched, injection molding (3) Heat distortion temperature (° C) According to JIS K7207, a test piece having a thickness of 6.4 mm, a width of 12.7 mm and a length of 127 mm was used, and the piece was bent without annealing. Stress is 18.6k
The measurement was performed at g / cm ² . (4) Melt flow rate (MFR) (g / 10 minutes) According to JIS K7210 As the measurement conditions, a resin temperature of 220 ° C. and a load of 10 kg were adopted. (5) Haze (cloudiness value) Based on JIS K7105 It measured with the injection molding board of thickness 2.5mm. The smaller the haze value, the better the transparency.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Name of item to be corrected] 0027

[Correction method] Change

[Correction content]

[0027]

[Table 2] Comparative Example 1 2 3 4 ────────────────────────────── Acrylonitrile (% by weight) 55 55 55 55 Styrene (Wt%) 45 45 45 45 Rubber content (wt%) − − − − Stearic acid (parts by weight) − 0.15 − − Ethylenebisstearic acid amide (parts by weight) − − 0.03 − Magnesium stearate (parts by weight) − − − 0.03 Tensile strength (Kg / cm ² ) 840 831 837 839 Izod impact strength 1.3 1.3 1.3 1.3 (Kg · cm / cm) Heat distortion temperature (℃) 95 94 95 95 Melt flow rate (g / 10 minutes) 23 24 23 23 Haze (%) 5 8 25 32 Scratch depth (μm) 200 g load 0 0 0 0 300 g load 3.5 0 0 0 Formability △ × ○ ○ ──────────────── ───────────────

[Procedure 3]

[Document name to be amended] Statement

[Name of item to be corrected] 0030

[Correction method] Change

[Correction content]

[0030]

[Table 3] *: AN of matrix part excluding rubber (butadiene)
Content

Claims (1)

[Claims] 1. The content of vinyl cyanide units is 40 to 8.
0.01 to 0.1 per 100 parts by weight of pellets on the surface of pellets of the rubber-reinforced vinyl cyanide-based graft copolymer and / or vinyl cyanide-based copolymer of 5% by weight.
A high nitrile resin pellet, which is obtained by substantially uniformly adhering an amount of higher fatty acid corresponding to parts by weight.