JPH1095917A - Resin composition and molded form therefrom - Google Patents

Abstract

PROBLEM TO BE SOLVED: To settle such a problem that, in thermoplastic resin composition for molding use, the antistatic performance on the surface of the molded form therefrom is hardly retained over a long period, leading to considerable troubles due to static electricity. SOLUTION: This resin composition comprises (a) a polyamide elastomer composed of polyamide skeleton and polyether-ester skeleton and (b) an ethylene- vinyl acetate-vinyl alcohol copolymer. Among others, when the total content of the vinyl acetate and vinyl alcohol (VA) in the component (b) is 10-45wt.%, the weight ratio:vinyl acetate/VA is (0:100) to (70:30), and the weight ratio (a)/(b) is (10:90) to (90:10), this resin composition has good molding processability and excellent mechanical properties and accomplishes its long-term antistatic effect, also being a molding material in itself and affording molding materials having excellent antistatic characteristics by compounding with various kinds of other thermoplastic resins.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a resin composition having processability and flexibility equivalent to a polyolefin resin, excellent mechanical properties, and having an antistatic effect for a long period of time.

[0002]

2. Description of the Related Art Synthetic polymer materials have been used in a wide range of fields because of their excellent properties. However, since they generally have high electrical resistivity and are easily charged, various problems caused by static electricity occur. As a method of imparting an antistatic property to a polyolefin resin represented by polyethylene, a method of applying a surfactant or the like to the surface, kneading the resin, or a water-absorbing compound such as polyalkylene oxide or an alkylamine. A method of kneading such an antistatic agent into a resin is known.

[0003]

However, surfactants and antistatic agents such as polyalkylene oxides and alkylamines have good initial antistatic properties, but are liable to bleed out and have poor water resistance. The antistatic property cannot be maintained over a period. For styrene resins such as polystyrene, fairly good antistatic formulations have been established, but for polyolefin resins, good formulations have not yet been established.

[0004]

Therefore, a study is made of a resin composition which is hard to bleed out, has excellent water resistance, has workability and flexibility equivalent to a polyolefin resin, and has an antistatic effect for a long period of time. As a result of the superposition, the present inventors have found that a composition comprising a polyamide elastomer (a) comprising a polyamide skeleton and a polyetherester skeleton and an ethylene-vinyl acetate-vinyl alcohol copolymer (b) exhibits good properties, and I've reached the point.

That is, the composition of the present invention can be used as an antistatic molding material by itself, or it can be used by blending it with another resin such as polyethylene as an antistatic agent. .

In such a composition, the total content of vinyl acetate and vinyl alcohol in the copolymer (b) is 10 to 45% by weight, and the weight ratio of vinyl acetate to vinyl alcohol is 0 to 100 to 100%. It is preferably 70:30.

In this composition, the composition ratio of component (a) to component (b) is preferably 10:90 to 90:10.

By using the composition itself or a molding material containing the composition, various molded articles such as sheets, films, and housings can be obtained. ^{When the} resistance is ¹³ Ω or less, excellent antistatic properties can be obtained over a long period of time.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The typical and best modes of the embodiment of the present invention will be specifically shown in the examples described below. This will be described in detail.

As the polyamide elastomer comprising a polyamide skeleton and a polyetherester skeleton used as the component (a) of the present invention, various known elastomers can be used. Preferred examples thereof include (C) and (e). ) A polymerized fatty acid having 20 to 48 carbon atoms, (f) azelaic acid and / or
Or sebacic acid and (g) a diamine having 2 to 20 carbon atoms, wherein the weight ratio (e) / (f) of (e) to (f) is 0.3 to 5.0, and The mixture was mixed at a temperature of 170 to 230 ° C. in a reaction vessel which was mixed so that all amino groups were substantially equivalent to all carboxyl groups and purged with nitrogen.
A polyamide oligomer having a number average molecular weight of 500 to 5,000 obtained by reacting for 5 to 1.0 hours and performing polycondensation,
(D) (h) a polyoxyalkylene glycol having a number average molecular weight of 200 to 3,000 or a mixture of a polyoxyalkylene glycol and an α, ω-dihydroxy hydrocarbon having a number average molecular weight of 200 to 3,000; A) a dicarboxylic acid having 6 to 20 carbon atoms, wherein all the carboxyl groups are substantially equivalent to all the hydroxyl groups, and the weight ratio (D) / (C) of (D) to (C) is 5 / 9
5-80 / 20, and in a reaction vessel purged with nitrogen, in the presence of a small amount of a catalyst at 200-280 ° C., 1-3
After polycondensation for a period of time,
A polyamide elastomer obtained by reacting until the melt viscosity at 50 ° C. becomes 5 Pa · s or more (Japanese Unexamined Patent Publication No. 5-32
0336). JP-A-6-12281
The polyetheresteramide shown in No. 7 can also be exemplified as other suitable ones.

(E) The carbon number used as the component is 20
As the polymerized fatty acids of ~ 48, unsaturated fatty acids, for example,
A polymerized fatty acid obtained by polymerizing a monobasic fatty acid having at least one double or triple bond having 10 to 24 carbon atoms is used. Specific examples include oleic acid, linoleic acid,
And dimers such as erucic acid.

When the number of carbon atoms used as the component (g) is 2 to 2,
As the diamine of 20, ethylenediamine, 1,4-
Diaminobutane, hexamethylenediamine, nonamethylenediamine, undecamethylenediamine, dodecamethylenediamine, 2,2,4-trimethylhexamethylenediamine, bis- (4,4′-aminocyclohexyl) methane, meta-xylylenediamine, etc. No.

The polyoxyalkylene glycol having a number average molecular weight of 200 to 3,000 used as the component (h) includes polyoxyethylene glycol, polyoxypropylene glycol, polyoxytetramethylene glycol, and ethylene oxide and propylene oxide. Examples include block or random copolymers, block or random copolymers of ethylene oxide and tetrahydrofuran, and mixtures thereof. Α, having a number average molecular weight of 200 to 3,000 used in combination
Examples of the ω-dihydroxy hydrocarbon include polyolefin glycol and hydrogenated polybutadiene glycol obtained by polymerizing an olefin or butadiene to form a hydroxyl group at the terminal and hydrogenating the double bond.

(I) When the number of carbon atoms used as the component is 6 to
Examples of the dicarboxylic acid of 20 include aliphatic dicarboxylic acids such as adipic acid, azelaic acid, sebacic acid and dodecanoic acid, aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid and diphenoxyethane dicarboxylic acid, and 1,4-
Alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid and 1,2-cyclohexyl-4,4′-dicarboxylic acid; In particular, dicarboxylic acids such as azelaic acid, sebacic acid, terephthalic acid, isophthalic acid and 1,4-cyclohexanedicarboxylic acid are preferred.

The ethylene-vinyl acetate-vinyl alcohol copolymer used as the component (b) is obtained by saponifying or grafting the ethylene-vinyl acetate copolymer by a known method. The total content of vinyl acetate and vinyl alcohol is 10 to 45% by weight, and the weight ratio of vinyl acetate and vinyl alcohol is 0: 100 to 70: 3.
0 is preferred. The best antistatic effect can be obtained when the composition ratio of the component (a) and the component (b) is 10:90 to 90:10.

The resin composition of the present invention may optionally contain
Phenolic, thioether, phosphite and other antioxidants, benzotriazole, benzophenone,
UV absorbers such as hindered amines, stabilizers such as metal deactivators, release agents and lubricants such as silicones and fatty acid amides, metal soaps, dispersants such as fatty acid amides,
Colorants such as dyes and organic and inorganic pigments, bromine-containing such as decabromodiphenyl ether, decabromodiphenylethane, 1,2-bis (tetrabromophthalimide) ethane, and tetrabromobisphenol A type epoxy resin flame retardant Flame retardants, 1,2,3,4,7,8,9,10,13,13,14,14-dodecachloro-1,4,4a, 5,6,6a, 7,10,10a, 11,12 Chlorine-containing flame retardants such as, 12a-dodecahydro-1,4,7,10-dimethanodibenzo (a, e) cyclooctene, metal hydrates such as magnesium hydroxide and aluminum hydroxide, and nitrogen-containing flame retardants such as melamine cyanurate And a flame retardant such as a phosphorus-containing flame retardant such as a condensed phosphate ester, and a flame retardant auxiliary such as antimony trioxide, antimony tetroxide, antimony pentoxide, and zinc borate.

Further, since the resin composition of the present invention has a polyamide skeleton, a polyetherester skeleton and an ethylene skeleton, other thermoplastic resins such as polyethylene, polypropylene, ethylene-vinyl acetate copolymer,
Olefinic resins such as ethylene-ethyl acrylate copolymer, ethylene-methacrylic acid copolymer, ethylene-methyl methacrylate copolymer, ethylene-acrylate ester-maleic anhydride terpolymer, and ethylene-propylene copolymer , Nylon 6, Nylon 6/66 copolymer, Nylon 4/6 copolymer, Nylon 12, Nylon 11 and other polyamides, and engineering plastics such as polyester resins to impart an antistatic effect.

Further, together with the resin composition of the present invention, a styrene-acrylonitrile-methacrylic acid copolymer, a styrene-acrylonitrile-glycidyl methacrylate copolymer, a styrene-acrylonitrile-methacrylamide copolymer, a methyl methacrylate-styrene-methacrylate Styrene-containing modified vinyl polymers such as acrylic acid copolymers and styrene-isoprene copolymers and their hydrogenated products, high vinyl styrene-isoprene copolymers and their hydrogenated products, styrene-butadiene copolymers and the like When a hydrogenated substance is added, polystyrene, AB
It can be added to a styrenic resin such as S to impart antistatic properties.

Further, by adding a cationic, anionic or nonionic surfactant or the like, more excellent initial antistatic performance can be imparted.

[0020]

The resin composition of the present invention has processability and flexibility equivalent to a polyolefin resin, has excellent mechanical properties, and has an antistatic effect for a long period of time. It is easy to process, and can be used in a wide range of fields, such as packaging films and wallpapers that dislike dust and dust due to static electricity, trays for electronic components, housings for home electric appliances, and the like.

[0021]

The present invention will now be described in detail with reference to Examples.
The present invention is not limited to the embodiments. The percentages in Examples and Comparative Examples are all based on weight.

Examples 1 to 13 and Comparative Examples 1 to 8 After mixing by a tumbler with the components and the mixing ratios shown in Tables 1, 2, 3, 4, 5 and 6, 30 m
After melt-kneading with a twin screw vent type extruder of mφ, it was pelletized. The pellets were formed by heating two rolls and a hot press, a cooling press or injection molding to prepare a test piece having a thickness of 2 mm. The antistatic property was evaluated by measuring the surface resistance value SR (unit: Ω) after standing at 23 ° C. and a humidity of 55% for 24 hours.

The long-term antistatic property is evaluated by leaving in water for 60 days, drying at 50 ° C. for 24 hours, wiping the surface with a cloth, and measuring the surface resistance after leaving for 24 hours at 23 ° C. and 55% humidity. did. The surface resistance was measured according to JIS K 6911. The applied voltage was 500 V for one minute.
Further, the pellets were processed into a film by an inflation molding machine, and the workability at that time was judged as good, good or not.

From Table 1, Table 2, Table 3, Table 4, Table 5, and Table 6, by adding the component (b) to the component (a), the surface resistance value becomes lower than each single component, It can be seen that there is a synergistic effect. In addition, the surface resistance does not increase over a long period of time, and the antistatic property is maintained. In particular, good properties are exhibited when the total content of vinyl acetate and vinyl alcohol in the ethylene-vinyl acetate-vinyl alcohol copolymer is 10 to 45% by weight and the weight ratio of vinyl acetate to vinyl alcohol is 0: 100 to 70:30. The best ratio is obtained when the composition ratio of the component (a) to the component (b) is 10:90 to 90:10.

No other resin system has a lower surface resistance value than the component (a) alone. When a nonionic surfactant is added to polyethylene, good antistatic properties are exhibited initially, but the surface resistance increases in a long-term test, and the antistatic effect is lost. The addition of magnesium hydroxide does not change the antistatic effect. By adding the component (a) and the component (b) to polyethylene or polyamide, the surface resistance value is reduced, and it is possible to impart antistatic properties for a long period of time. The same effect can be obtained in polystyrene by adding a hydrogenated styrene-isoprene copolymer. In addition, the workability is all good.

Description of Abbreviations in Table PAE1: Softening point: 153 ° C., specific gravity: 1.02, melt index (hereinafter referred to as MI) 5 g / 10 min (19)
Polyamide elastomer PAE2 having a softening point of 165 ° C, specific gravity of 1.02, and MI4 at a temperature of 0 ° C and 2.16 kg (the same applies to the following numerical values) PAE2: Polyamide elastomer of MI4 EVA-OH1: Total content of vinyl acetate and vinyl alcohol Is an ethylene-vinyl acetate-vinyl alcohol copolymer having a weight ratio of vinyl acetate to vinyl alcohol of 1: 1 EVA-OH2: a total content of vinyl acetate and vinyl alcohol of 25% by weight, vinyl acetate and vinyl alcohol Ethylene-vinyl acetate-vinyl alcohol copolymer having a weight ratio of 1: 1 EVA-OH3: the total content of vinyl acetate and vinyl alcohol is 10% by weight, and the weight ratio of vinyl acetate and vinyl alcohol is 1: 1. Vinyl acetate-vinyl alcohol copolymer EVA-OH4: vinyl acetate and vinyl EVA: an ethylene-vinyl acetate-vinyl alcohol copolymer having a total alcohol content of 45% by weight and a weight ratio of vinyl acetate to vinyl alcohol of 1: 9 EVA: a vinyl acetate content of 25% by weight and an ethylene-vinyl acetate copolymer of MI2 Polymer PE: high-density polyethylene MI = 0.03, specific gravity 0.952 PP: polypropylene MI = 2.6, specific gravity 0.9
0 PA: Nylon 6/66 copolymer, melting point 190 ° C. PS: High impact polystyrene MI = 3.
0, specific gravity 1.05 SEPS: hydrogenated styrene-isoprene copolymer, styrene content 30 wt%, specific gravity 0.92 NONION: nonionic surfactant Electrostripper TS-2B (manufactured by Kao Corporation) Mg (OH) ₂ : magnesium hydroxide

[0027]

[Table 1]

[0028]

[Table 2]

[0029]

[Table 3]

[0030]

[Table 4]

[0031]

[Table 5]

[0032]

[Table 6]

Claims (5)

[Claims] 1. A polyamide elastomer comprising a polyamide skeleton and a polyetherester skeleton, and (b)
A resin composition comprising an ethylene-vinyl acetate-vinyl alcohol copolymer. 2. The ethylene-vinyl acetate-vinyl alcohol copolymer has a total content of vinyl acetate and vinyl alcohol of 10 to 45% by weight and a weight ratio of vinyl acetate and vinyl alcohol of 0 to 100 to 70 to 30. The resin composition according to claim 1, wherein 3. The composition ratio of component (a) to component (b) is 10
The resin composition according to claim 1, wherein the ratio is 90 to 90:10. 4. A molded article comprising the resin composition according to claim 1. 5. The method according to claim 4, wherein the surface resistance is 10 ¹³ Ω or less.
The molded article according to the above.