JPS62104855A - Rubber composition with improved blooming - Google Patents

Abstract

PURPOSE:A rubber composition that is obtained by adding a specific N- substituted ammonium salt to an ethylene-alpha-olefin polymer rubber, thus being freed from blooming in vulcanization without any adverse effect on moldability and physical properties of the vulcanized products. CONSTITUTION:The objective composition is obtained by adding 0.3-20pts.wt. of an N-substituted ammonium salt of the formula (R1 is monovalent hydrocarbon; R2 is H, monovalent or divalent hydrocarbon; R3, R4 are H, monovalent hydrocarbon; n is 0, 1; X<-> is anion such as Cl<->) and 0.3-20pts.wt. of sulfur or a sulfur-containing compound as a vulcanizer to 100pts.wt. of an ethylene-alpha- olefin copolymer rubber or an alpha-olefin copolymer rubber.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention provides an ethylene/α-olefin copolymer rubber (
Regarding the blooming improvement of the composition (hereinafter sometimes simply abbreviated as EPDM), more specifically, the EPDM composition has N-
By blending a substituted ammonium salt, blooming of sulfur or a sulfur-containing compound blended as a vulcanizing agent is prevented.

(Prior art) EPDM does not contain double bonds in its main chain, has ozone resistance,
It is well known that rubber has excellent properties such as weather resistance and heat resistance.

However, since it does not have a double bond in its main chain,
The vulcanization speed is low compared to other general-purpose rubbers, especially when vulcanization is performed using sulfur or sulfur-containing compounds.
In order to increase the vulcanization rate to the same extent as other general-purpose rubbers, it is necessary to use larger amounts of these vulcanizing agents and vulcanization accelerators than for general-purpose rubbers. That is, natural rubber (NR), styrene-butadiene rubber (SBR), butadiene rubber (B
It is very common to use 2 to 5 times the amount of vulcanization accelerator compared to R) and the like.

If you actually want to complete the vulcanization of EPDM in a short time,
- Examples include 100 parts by weight of rubber component, 1.5 parts by weight of thiuram vulcanization accelerator, and 2.5 parts by weight of dithioate vulcanization accelerator.
Generally, a large amount of vulcanizing agent and vulcanization accelerator is blended in a total of 8.5 parts by weight, consisting of 2.5 parts by weight of thiazole-based vulcanization accelerator, and 2 parts by weight of sulfur. On the other hand, SBR is generally blended in a total amount of about 2.5 to 3 parts by weight.

These sulfur and sulfur-containing compounds used as vulcanizing agents and vulcanization accelerators have poor compatibility with EPDM, so if large amounts are added, they will precipitate from the vulcanizate onto the surface. The so-called blooming phenomenon, in which the particles crystallize in the process, cannot be avoided.

As a method to solve this blooming phenomenon, it has been proposed to incorporate a non-reactive phenol formaldehyde resin as a tackifier (% Kosho 59-1534).
(Refer to Publication No. 5), this method is still unsatisfactory in that the EPDM composition becomes sticky, the processability is impaired, and the compression set of the vulcanizate increases.

In addition, a method of blending an alkylolamide compound as an anti-blooming agent has also been proposed (Japanese Patent Application Laid-Open No. 58-118).
113235), no effective preventive effect has been obtained.

At present, no effective means for preventing blooming of vulcanizates obtained from gp DM compositions has yet been found.

(Object of the invention) Therefore, the object of the present invention is to improve moldability, physical properties of vulcanizate,
An object of the present invention is to provide an ethylene/α-olefin copolymer rubber composition in which blooming of a vulcanizate is effectively prevented without impairing various properties such as heat resistance, weather resistance, paintability, and adhesiveness.

(Means for Solving the Problems) According to the present invention, the following general formula, (wherein R1 is a monovalent hydrocarbon group, R2 is a hydrogen atom or a monovalent or divalent hydrocarbon group, and R3 is A hydrogen atom or a monovalent hydrocarbon group, R4 is a hydrogen atom or a monovalent hydrocarbon group, and the monovalent hydrocarbon group R1 and the monovalent or divalent hydrocarbon group R2 are directly or , 0. may be linked via S to form a heterocycle, n is the number of O''! or 1, and when R2 is a divalent hydrocarbon group, the number of O. X- is Ct-, Br-
An ethylene/α-olefin copolymer rubber composition characterized in that it contains an N-substituted ammonium salt represented by: be done.

(Function of the Invention) The present invention provides an N-substituted ammonium salt represented by the above general formula in an ethylene/α-olefin copolymer rubber or an α-olefin copolymer rubber.
-By blending with olefin copolymer rubber,
This is based on the new finding that plumping is effectively prevented during vulcanization of the rubber.

(Embodiments of the invention) Ethylene/α-olefin copolymer comb The ethylene/α-olefin copolymer rubber used in the present invention is
Ethylene and α-olefins such as propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-
It is a copolymer with one or more α-olefins having 3 to 10 carbon atoms such as pentene, 1-octene, and 1-decene.

A polyene component may be copolymerized in Saraniko's ethylene/α-olefin copolymer comb.

Specifically, the polyene component includes 1,4-hexanoene, 1,6-octanoene, 2-methyl-1,5-hexadiene, 6-methyl-1,5-heptadiene, and 7-methyl-1,6-octanoene. linear nonconjugated diene,
Cyclohexadiene, dicyclo-4-ntadiene, methyltetrahydroindene, 5-vinyl-2-norgernene,
5-ethylidene-2-nordelene, 5-methylene-2
- cyclic non-conjugated dienes such as norguernene, 5-isopropylidene-2-norguernene, 6-chloromethyl-5-impropenyl-2-norguernene, 2,3-noisopropylidene-5-norbornene, 2-ethylidene -3
Typical examples include trienes such as -impropylidene-5-norbornene, 2-f lopenyl-2,2-norbornadiene, 1,3,7-octatriene, and 1,4,9-decatriene. Suitable polyenes are cyclic non-conjugated tzenes and 1,4-hexadiene, especially dicyclopentadiene or 5-ethylidene-2-norgernene.

These polyene components are copolymerized to have an iodine value of at most 30, preferably 20 or less.

α-Olefin Copolymer Rubber The α-olefin copolymer rubber used in the present invention is an elastomer obtained by copolymerizing two or more α-olefins containing three or more carbon atoms.

The α-olefins constituting such a copolymer rubber include, for example, propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-heptene, 1
-octene, 1-decene, etc. Among them, a copolymer of propylene and 1-butene is most often used. Furthermore, in terms of sulfur vulcanizability, in addition to the above copolymer components,
A multicomponent polymer containing a small amount of non-conjugated polyene component is preferred.

Preferred non-conjugated polyenes are dienes,
The diene constituting the ethylene/α-olefin/diene copolymer can be sufficiently used.

Further, the ethylene content of this ethylene/α-olefin copolymer rubber is preferably in the range of 50 to 85 moles, particularly 60 to 75 moles.

N-substituted ammonium salt In the rubber composition of the present invention, the above-mentioned ethylene α
- The olefin copolymer rubber has the following general formula: or may form a heterocycle containing one or more of 0, N, and S.

X- is CL-1Br-* H3O4- or CH,5
Represents an anion of an acid such as O4-.

m and n are numbers from 0 to 4. ) An important feature is the incorporation of an N-substituted ammonium salt represented by:

This ammonium salt is known as a so-called cationic surfactant, and specifically includes the following.

(a) Monohigher alkyl tri-lower alkylammonium salt RI N+ (R2)3.X- R9 carbon number 12-18, Cl3F, "R2; carbon number 1-4°
(CnF1 indicates that an alkyl group containing n carbon atoms contains one double bond.

same as below. ) (b) Dihigher alkyldilower alkyl ammonium salt R'2N"(R2)2.X- R1 C12-18 R9 C1-4 RN"(CH,)2C2H5-X""R; carbon number 12-18018F1 j R9 C1-4 (,) Higher alkylpyridinium salt R; C12-4
18 X; CL, Br r I r (f) Higher alkylquinolinium salt R;
18 X: CL, Br (g) High i alkylisoquinolinium salt R; C number 1
2-18 X; C2, Br (h) Higher alkylpyridinium sulfate R; C number 1
2 or more (i) Acylaminoethylmethyldiethylammonium salt RCONHCH2N+(C2H5)2cH3・cH3s
o4-R; C number 17017F1 There is also a medium-fine one quaternized with pen sol chloride.

(j) Alkylamidopropyldimethylpendylammonium salt CH2C6H3 R;C is commercially available.

(k) Fatty acid polyethylene polyamide RCO (NH
C2H4)nNH.

R; C number 17, C17F4. n=2<1> acylaminoethylpyridinium salt) acylcolaminoformylmethyl viridinilla (n) N-(3-alkoxy,
2-hydroxyglobil) trialkylammonium chloride pa4 R1; C number 12-13° R2; C number 2. -1 or 16.18 R3, R4; The N-substituted ammonium salt having 1 to 2 or more carbon atoms is usually 0.5 parts by weight per 100 parts by weight of ethylene/α-olefin copolymer rubber, although it varies depending on the type. Preferably, it is used in an amount of 1 to 15 parts by weight. If the amount is less than 0.5 parts by weight, the desired pluming prevention effect will be diluted, and if the amount is less than 15 parts by weight,
Even if it is used in an amount larger than 1 part by weight, no further effect can be obtained, and in some cases, it may bleed onto the surface of the vulcanizate.

Preparation of Rubber Composition The rubber composition of the present invention is obtained by blending the above-mentioned ethylene/α-olefin copolymer rubber and N-substituted ammonium salt, but natural rubber or other synthetic rubber may be used as the rubber component. It is also possible to blend within a range that does not impair the properties of the ethylene/α-olefin copolymer rubber.

Further, as a vulcanizing agent and a vulcanization accelerator, sulfur and sulfur-containing compounds such as morpholine nosulfide, alkylphenol sosulfide, thiuram type, thiazole type, dithiocarbamate type, and thiourea type are blended.

These vulcanizing agents and vulcanization accelerators are used in amounts known per se, for example in an amount of 0.2 to 20 parts by weight, particularly 0.5 to 15 parts by weight per 100 parts by weight of the rubber component. Ru.

Of course, it is also possible to use these vulcanizing agents together with organic peroxides and oxime compounds.

In preparing the rubber composition of the present invention, the N-substituted ammonium salt can be blended by any method.

For example, the ammonium salt may be blended directly with the rubber component, or it may be blended with a vulcanizing agent and a vulcanization accelerator in advance and surface-treated with these compounds, and then blended with the rubber component. It's okay. No matter which method is adopted, the predetermined pluming prevention effect will not be lost.

The rubber composition of the present invention may also include other rubber compounding agents known per se, such as rubber reinforcing agents, inorganic fillers, softeners,
Tackifiers, vulcanization aids, anti-aging agents, foaming agents, lubricants, flame retardants, etc. can also be blended in amounts known per se.

The rubber composition of the present invention obtained in this way can be processed using an extrusion molding machine,
A vulcanized product is obtained by molding into the desired shape using a calendar roll or press, and at the same time as the molding, or by introducing the molded product into a vulcanization tank and heating it at a temperature of usually 140 to 260°C for 1 to 120 minutes. be able to.

Vulcanization may be performed using a mold or without using a mold.

(Effects of the Invention) As is clear from the examples described below, the vulcanizate obtained from the ethylene/α-olefin copolymer rubber composition of the present invention is It has effectively improved blooming properties without sacrificing its excellent adhesive properties, and has excellent heat resistance, weather resistance, and ozone resistance without reducing paintability, adhesion, or reducing the commercial value due to changes in surface hue. We provide rubber products with

In particular, various automotive parts such as window frames, glass runs and channels, and door mirror boots that require ozone resistance and adhesive properties, roofing sheets and various building material parts that require weather resistance and adhesive properties, and heat resistant parts that require heat resistance. It is suitable for various types of hoses.

The invention is illustrated by the following example.

Example 1 An EPDM composition was prepared using the following formulation.

Compound EPDM (Mitsui EPT3070: manufactured by Mitsui Petrochemicals)
100 parts by weight zinc white
5 Stearic acid I
11 Polyethylene glycol 1
〃FEF car? Black 12
0 Paraffin oil
45 Calcium oxide 1
0 Sulfur 1.0
1/ During the preparation, the vulcanization accelerator was kneaded with an open roll with a surface temperature of 50°C, and the others were mixed with a Banbury mixer.

The following additives A to EPD were added to this EPDM composition.
Parts by weight of MIOO 92 parts by weight (5 parts by weight only of the alkylphenol resin of L) were kneaded using open rolls with a surface temperature of 60°C to prepare samples 2 to 13. Sample 1 was prepared without adding this additive at all.

Additives Lauryl trimethyl ammonium chloride Stearyl trimethyl ammonium chloride (general formula) % formula % (general formula) (C) High [alkyl benzyl dimethyl ammonium chloride (general formula) Higher alkyl; C16-C18Φ
) N, N, N, N-(3-alkoxy/2-hydroxypropyl) stearyldimethylammonium chloride (general formula) (6) Higher alcohol sulfate ester soda salt (g) Polyoxyethylene lauryl ether (G) holoxyethylene Nonylphenyl ether (B) Sorbitan monolaurate (I) Polyoxyethylene sorbitan monolaurate (J) ylelJ ethylene glycol monostearate (6) Polyoxyethylene oxypropylene condensate (L) Alkylphenol resin trade name: Hytanol 1501 (manufactured by Hitachi Chemical) Each sample was heated at 180°C for 5 minutes (1.0 for compression set test).
After press vulcanization (for 1 minute), a plumping test and various physical property tests were conducted.

The results are shown in Table 1.

In addition, the pluming test was determined after one month in a constant temperature room at 25°C and after 16 hours in an ozone test tank at 50 pphm and 40°C, and was indicated by the following symbols.

◎: Occurrence of blooming was not observed. ○: Slight occurrence of blooming.

From the above results, it is understood that in the examples of the present invention (samples 2 to 5), the occurrence of pluming was almost completely prevented, and the compression set was also reduced.

In other comparative examples, the effectiveness in preventing pluming was small, and in particular, there was no effect at all under ozone exposure.

In addition, an example in which alkylphenol resin was blended (sample 13)
It is understood that compression set deteriorates in addition to the above, and its use is limited.

Example 2 In Example 1, the ammonium salt of the additive was added to 1 to 1
Samples 14 to 16 were prepared by changing the amount within the range of 0 parts by weight, and various tests were conducted in the same manner.

The results are shown in Table 2.

Table 2 Example 3 Samples 17 and 18 were prepared in the same manner as in Example 1 except that the additive ammonium salt was used and the vulcanization accelerator shown in Table 3 was used. I conducted a test.

The results are also shown in Table 3.

Table 3 ZnBDC; Non-n-butyldithiocarbamate Zinc E
U; ethylene thiourea

Claims (4)

[Claims] (1) The following general formula, ▲ Numerical formula, chemical formula, table, etc.▼ (In the formula, R_1 is a monovalent hydrocarbon group, R_2 is a hydrogen atom or a monovalent or divalent hydrocarbon group, R_3 is a hydrogen atom or The monovalent hydrocarbon group R_4 is a hydrogen atom or a monovalent hydrocarbon group, and the monovalent hydrocarbon group R_1 and the monovalent or divalent hydrocarbon group R_2 are directly or N, O, may be linked via S to form a heterocycle, n is a number of 0 or 1, and when R_2 is a divalent hydrocarbon group, it is a number of 0; Cl^-, Br^-, HSO_4^- or CH_3SO_4^-, which is an anion of an acid such as); Copolymer rubber or α-olefin copolymer rubber composition. (2) The rubber composition according to claim 1, which contains the N-substituted ammonium salt in a proportion of 0.3 to 20 parts by weight per 100 parts by weight of the ethylene/α-olefin rubber component. (3) The rubber composition according to claim 1 or 2, which contains sulfur or a sulfur-containing compound as a vulcanizing agent. (4) Claim 3 in which sulfur or a sulfur-containing compound is contained in a ratio of 0.3 to 20 parts by weight per 100 parts by weight of the ethylene/α-olefin copolymer rubber component.
The rubber composition described in .