JPS6243410A - Powder rubber - Google Patents

Abstract

PURPOSE:Powder rubber which has improved compatibility and dispersibility into rubber and resins and can improve extremely impact properties of rubber and resins, comprising an ethylene-alpha-olefin copolymer which is modified with a polar group-containing compound and contains a cyclohexane-insoluble component in a specific ratio. CONSTITUTION:For example, a polar group-containing compound such as acrylic acid, etc., is kneaded in a molten state with an ethylene-alpha-olefin and an organic peroxide by a twine screw extruder an powdered to give ethylene-alpha-olefin copolymer powder rubber which is modified with the polar group-containing compound and 30-100wt% cyclohexane-insoluble component (ratio not passing through 100 mesh wire net after dissolution at 30 deg.C for 5hr). An ethylene-butene-1 copolymer is preferable as the copolymer. Preferably 0.3-20pts.wt. polar group containing compound and 1-3pts. 1wt organic peroxide are used based on 100pts.wt. copolymer.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention provides ethylene-α- which has good mixing and dispersibility with rubbers or resins having polar groups and is particularly useful for improving S seasonality when mixed with resins. Olefin copolymer (hereinafter referred to as EP■) M
Sometimes abbreviated as ``class''. ) relating to powdered rubber.

[Conventional technology]

EP (DIM) is a saturated hydrocarbon polymer and has better weather resistance and heat resistance than diene rubber, so it is used for automobile hoses, window frames, other parts, industrial products, and blended with polypropylene resin for automobile bumpers. It is used for a wide range of purposes.

[Problem that the invention seeks to solve]

EP ■) Since M is a saturated hydrocarbon polymer, it has poor compatibility when mixed with rubbers and resins that have polar groups, so even if it is mixed uniformly, it will phase separate after being left for a long time, resulting in a mixture with good physical properties. I can't get it.

Therefore, methods of grafting compounds such as acrylic acid, maleic anhydride, acrylamide, etc. to E P (D) M, and methods of chlorination and sulfonation have been reported. However, since these EPIDjMs having added polar groups are generally obtained in the form of blocks or pellets, they have poor mixing and dispersibility in thermosetting resins and do not lead to significant improvements in physical properties.

In other words, when mixing with a thermosetting resin such as a novolac type phenolic resin, even if you try to knead it using a kneading machine such as a roll, the viscosity of the thermosetting resin melt is low, so it cannot be mixed with a conventional block shape or EPID) M having pellet-like polar groups cannot be kneaded and the mixture is not uniformly dispersed. In addition, with self-curing thermosetting resins, the curing reaction progresses, so the kneading process described above may not be possible. :4 There was a drawback that the mixture was not mixed properly.

[Failure to solve the problem]

In view of the above circumstances, the present inventors conducted extensive research to obtain EP(D)Ms having polar groups in powder form rather than in block or pellet form from the viewpoint of mixing and dispersibility. The objective was achieved by strictly controlling the crosslinking density of the EP ■)M group. That is,
If the crosslinking density of EP(2)M class having polar groups during production is low, the product will become lumpy, and if it is too high, the production equipment will be overloaded, the production equipment will trip, and production will become impossible. We discovered that to achieve powderization, it is necessary to delicately control the amount and type of organic peroxide (decomposition temperature), the heat history added during production, and the combination of noa air. ))
The present invention was completed based on the successful powderization of Class M and the knowledge that this powdered rubber exhibits excellent dispersibility when mixed into rubbers and resins.

The present invention will be explained in detail below. E used in the present invention
P■) One or more α-olefins selected from ethylene as M class and α-olefins having 3 or more carbon atoms as α-olefins, such as propylene, butene-1, hexene-1, octene-1, etc. or a copolymer obtained by copolymerizing these with one or more nonconjugated dienes selected from ethylidene norbornene, synchlopentadiene, 1,4-hexadiene, etc. is used. It will be done. EP(D)Ms include ethylene-propylene-ethylidenenorbornene copolymer, ethylene-
Propylene-dinoclopentadiene copolymer, ethylene-propylene copolymer, ethylene-butene-1-ethylidenenorbornene copolymer, ethylene-butene-1-synchropentadiene copolymer, ethylene-butene-1 copolymer is preferred. Here, the total amount of ethylene in EP(D)MfJ4 is preferably 10 to 85% by weight, and the degree of unsaturation is preferably 5 to 4 in terms of iodine value. or,
EP[F])M having a polar group refers to the above EP(D
) It is a reaction product of Group M and a compound containing a polar group shown below.

Compounds having polar groups used in the present invention include groups such as carboxyl groups, carboxylic acid ester residues, carboxylic anhydride residues, amino groups, imino groups, hydroxyl groups, sulfonyl groups, chlorosulfonyl groups, and dimethylchlorosilane groups. Compounds, specifically acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, vinylbenzoic acid, vinyl phthalic acid, methyl methacrylate, maleic acid monomethyl ester, maleic acid monoethyl ester, fumaric acid monoethyl ester , maleic anhydride, itaconic anhydride, allylamine, maleimide, acrylamide,
Methacrylic acid amide, allyl alcohol, dimethylvinylchlorane, 2-trichlorolylphtadiene, 2
Examples include compounds such as -triethoxy//rilputadier/.

Furthermore, the organic peroxides used in the present invention include teha, henzoylperoquinde, dichloropenzoylperoquinde, dicumylberoquinde, di-tert-butylperoquinde, 2,5-dimethyl-2,5-dimethylperoquinde, (peroxide benzoate) hexyne-3,1,4-bis(tert)
-phthylberoxyinpropyl)benzene, lauroylperoquindo, tert-butylperacetate), 2
．． 5-dimethyl-2,5-di(tert-butylperoxy)hexyne-3,2,5-dimethyl-2,5-di(
tert-butylperoxy)hexane, tert-
butylperbenzony), tert 7” tylperuenylacetate, tert-butylperueisobutyrate, tert-butylperue 5CC-octoate,
Examples include azobisisobutyronitrile, dimethylazoisobutyrate, among which dicumyl peroxide, tert-7"f peroxide, 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane -3,2,5-dimethyl-2,5-di(tert-butylperoxy)hexane and 1,4-bis(tert-phthylberoxyinpropyl)benzene are preferred.

The powder rubber of the present invention contains 0.1 to 60 parts by weight (preferably 0.3 to 20 parts by weight) of a compound having a polar group and 0.5 parts by weight of an organic peroxide based on 100 parts by weight of the aforementioned EPQ)) M group. If the amount of the compound is less than 0.1 part by weight (preferably 1 to 3 parts by weight) and has a polar group, phase separation will occur even if the resulting rubber is mixed with a thermosetting resin, etc., resulting in poor impact resistance. properties are not improved. Moreover, when the amount exceeds 60 parts by weight, the obtained rubber itself takes on resinous properties and is no longer suitable as an impact resistance imparting agent. In addition, the organic peroxide content is 0.
If the amount is less than 5 parts by weight, powdering will not occur.

To obtain the powdered rubber of the present invention, a predetermined amount of EPG)) M-class polar group-containing compound and organic peroxide are weighed and prepared using a known method such as a Henschel mixer, ■-blender, ribbon blender, tumbler blender, etc. After mixing with etc.,
Examples include a method of kneading and powdering using a Banbury, Kneader 1 continuous kneader, etc., and a method of simultaneously performing melt-kneading and powdering using a ↓ screw extruder or twin screw extruder.

The kneading temperature and kneading time vary depending on the decomposition temperature of the organic peroxide used and therefore cannot be unconditionally defined, but generally a range of 150 to 300°C and 0.5 to 30 minutes is used. Preferably, for example, the extruder temperature is set at a temperature 10 to 30°C higher than the 1-minute half-life temperature of the organic peroxide used, the average residence time is kept at 0.5 to 5 minutes, and the addition of the organic peroxide is Use an amount of 1 to 3 P) (R).

The resulting powdered rubber preferably has a particle size of 10 mesh or less in terms of mixing and dispersibility, and in order to obtain a powdery form, the hexane insoluble matter must necessarily be 30 to 100, preferably 60 to 990. 99 parts by weight are required. In producing the powdered rubber of the present invention, various anti-aging agents such as phenolic, amine, and phosphorus type, fillers such as carbon and inorganic fillers, crosslinking aids, etc. may be used in combination as necessary.

When the powdered rubber of the present invention is blended with thermosetting resins such as phenolic resins, urea resins, and melamine resins, it is uniformly dispersed and exhibits an excellent effect in improving the impact resistance of these resin compositions.

It is also effective in improving the impact resistance of thermoplastic resins such as polyamide, polyester, polybutyl phthalate, polypropylene, and epoxy resins.

In these cases, the powdered rubber is 0.1 to 100 to 0.1 to resin.
~50 parts by weight are used.

Molded products made by blending powdered rubber with various resins are useful for improving the impact resistance of molded products such as automobile parts such as inner panels and bumpers, electrical parts such as plugs and outlets, food products, and household items such as the bodies of electrical appliances. be.

[Effect]

Why can the method of the present invention be used for powdering?

And does powdered rubber have good mixing and dispersibility?→4-Chewing 4
Let me explain its mechanism of action.

In general, EP (01M types have a molecular weight of 150 to 300 in the non-crosslinked state)
It is a well-known fact that it does not turn into a powder in the temperature range of °C, and in such conditions, it does not take much air. In the present invention, a compound having a polar group is added to EPnM using an organic peroxide in a kneader or an extruder, and semi-crosslinked (10 to 5
otfcI)), then continued kneading and shearing, allowing the remaining organic peroxide to progress from a semi-crosslinked state to a crosslinked state (50 to 99 d in cyclohexane insolubles), making it possible to powder it. Ta.

Also, for example, when normal rubber and thermosetting resin are mixed at a temperature above the melting point of the thermosetting resin, the thermosetting resin is molten, so almost no shear is applied to the rubber; Even after mixing, the mixture remains in the thermosetting resin in the same shape as before mixing.

That is, the rubber is non-uniformly dispersed in the thermosetting resin. Therefore, the thinner the shape of the rubber before mixing, the better the mixing and dispersibility. That is, mixing and dispersibility is better in powder form than in block or pellet form.

〔Example〕

The present invention will be specifically explained below with reference to Examples, but the present invention is not limited in any way by these Examples unless it departs from the gist thereof.

Example-1 E P with ethylidene norbornene content of iodine a of 15 and Mooney viscosity of MLQ+4 (100°C) = 90
DM (JSRFP57P: made by Japan Synthetic Rubber) 100
For Juhou Jachi, maleic anhydride (special grade commercial reagent)
1 part by weight of 1 part by weight of pulverized in A drum
Product name: Kayahexa-AD (manufactured by Kayaku Nouri) 2 parts by weight,
Anti-aging agent (product name: ANTAGE BHT: Kawaguchi Chemicals)
Mix 2 parts by weight well in advance and place in a 55mφ15 basket φ1.
The cylinder and die temperature were set at 200°C, and the screw rotation speed was 90 rpm.
When extruded at a residence time of 1.5 minutes, powdered rubber was obtained.

The obtained powdered rubber contained 87 portions of nclohexane insoluble matter and passed through a 10-meter sieve in total.

Comparative Example-1 For EPDMI O0 parts by weight used in Example-1,
1 part by weight of maleic anhydride and 0.3 parts by weight of Kayahexa-AD were extruded in the same manner as in Example-1. However, the obtained rubber was not powder-like but pellet-like.

Example 2 Extrusion was carried out in exactly the same manner as in Example 1 except that Antige BIT was not used. The obtained rubber was in the form of a powder and had a dichlorohexane insoluble content of 98 parts by weight.

The obtained powdered rubber passed through a 10 mesh sieve.

Example-3 100 parts by weight of the same EPDM as in Example-1, 5 parts by weight of acrylic acid, and 2 parts by weight of Kayahexa-AD were mixed well in advance, and the temperature of the cylinder and die was adjusted using a 55 cage φ single-screw extruder (full flight type). Extrusion was carried out at a temperature of 200° C., a screw rotation speed of 9 Orpm, and a residence time of 1.5 minutes. The obtained rubber was a powdered rubber and contained 95 parts insoluble in cyclohexane.

The obtained powdered rubber also passed through a 10 mesh sieve.

Example-4 100 parts by weight of the same EPDM as in Example-1, 10 parts by weight of methyl methacrylate, and 2 parts by weight of Kayahexa-2 were well mixed in advance, and using a 55raφ single-screw extruder (full flight type),... The temperature of the linder and die was set at 200° C., and extrusion was carried out at a screw rotation speed of 90 rpm and a residence time of 1.5 minutes to obtain a powdered rubber.

The obtained powdered rubber contained 93 parts of dichlorohexane insoluble matter and passed through a 10-mesh sieve.

Example-5 Powder rubber 152 obtained in Example-1, novolac type phenol resin 150? , hexamethylenetetramine l!
A mixed composition was obtained by kneading for 5 minutes with a roll at M'k of 140°C. The resulting mixed composition was crushed with a hammer and then pulverized with a punch. The resulting powdery mixed composition was uniform.

It was formed into a 4fi sheet using a 160° C. heat press, and a 12.7 m wide strip-shaped Izod impact test specimen was prepared using a universal cutter. Izotsu impact strength (25
°C, unnotched, 20 kp-crn) is 4.8 kq
It was f-cJcm.

Comparative Example 2 Izot impact strength was measured in the same manner as in Example 5 except that no powdered rubber was used. The Izod impact strength of the phenolic resin alone was 1.31<9f.~False.

Comparative Example 3 The Izot impact strength of the non-powdered maleic anhydride modified EPDM 4 blended phenol resin was measured in the same manner as in Example 5 except that the rubber obtained in Comparative Example 1 was used. 2.5 kyf-
cm/cm. In this case, when the mixed composition was crushed with a mortar, it was not completely powdered and small lumps were observed.

Comparative Example-4 Powder EPDM'e was obtained in exactly the same manner as in Example-1 except that maleic anhydride was not used. This powder EPDM
Izot impact strength was measured in the same manner as in Example 5 except that k15F was used.

The Izod impact strength of the phenolic resin blended with powdered EPDM is 1. Ohf-crrv't: n+.

In this case, when the mixed composition was ground with a mortar, a fine powder was obtained.

〔Effect of the invention〕

The powdered crosslinked EPG)) Class M rubber obtained by the present invention has good mixing and dispersibility with thermosetting resins, so it has a remarkable effect of improving impact resistance. It is useful for various purposes because it improves properties.

Claims (4)

[Claims] (1) Ethylene-α-olefin copolymer powder rubber modified with a compound having a polar group and having a cyclohexane insoluble content of 30 to 100% by weight (fraction that does not pass through a 100-mesh wire mesh after melting at 30°C for 5 hours). (2) Claims in which the polar group is a carboxyl group, a carboxylic acid ester residue, a carboxylic acid anhydride residue, an amino group, an imino group, a hydroxyl group, a sulfonyl group, a chlorosulfonyl group, a dimethylchlorosilane group, or a trichlorosilane group Powdered rubber according to item (1). (3) The powdered rubber according to claim (1), wherein the particle size of the powdered rubber is 10 mesh or less. (4) Mixing a compound having a polar group, an ethylene-α-olefin copolymer, and an organic peroxide, or mixing an ethylene-α-olefin copolymer having a polar group and an organic peroxide. The powdered rubber according to claim 1, obtained by subjecting the powdered rubber to a heating step.