JPS60255807A - Ethylene/propylene copolymer rubber - Google Patents

Abstract

PURPOSE:The titled compolymer rubber having improved mechanical strength and processability and specified iodine value, tensile stress at maximum and 100% elongation, cyclohexane-insoluble portion content and heat of fusion. CONSTITUTION:Ethylene is copolymerized with propylene and a diolefin at a molar ratio of 0.06-0.25:-0.1:0-0.1 in the presence of a catalyst system comprising an organometallic compound containing a metal of Group I -III of the periodic table and a transition metal compound having a metal selected from Groups IV-VI and VIII of the periodic table to obtain a copolymer rubber having an ethylene unit/propylene unit weight ratio of 80:20-40:60, a content of bound diolefin units of 0-50 (in terms of an iodine value), a maximum tensile stress at 25 deg.C(sigmamax) of 20-150kgf/cm<2>, a 100% elongation tensile stress (sigma100)<=20kgf/ cm<2>, a ratio (A) of sigmamax to sigma100, >=B as defined by the equation [wherein C is a propylene content (wt%)], a cyclohexane-insoluble portion content at 30 deg.C<= 15wt% and a heat of fusion of crystals having a m.p. of 50-100 deg.C as determined by differential scanning calorimetry >=6% of the total heat of fusion.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Application of Industry-1- The present invention relates to an ethylene film with improved mechanical strength and workability.
The present invention relates to a novel ethylene-propylene copolymer rubber consisting of a zolopylene copolymer and a novel ethylene-propylene copolymer rubber consisting of an ethylene-propylene-diolefin copolymer.

Technical background Ethylene-propylene-diolefin copolymer (EPI)
)M), or ethylene-propylene copolymer (EP
M) is currently produced industrially and is used in automobile-related, construction-related,
It is widely used as a rubber material for electrical equipment, etc. Due to its molecular structure, ethylene-propylene copolymer-flz has superior weather and heat resistance compared to other diene rubbers, such as natural rubber, polyisoprene rubber, polybutadiene rubber, etc. , its applications have been increasing more and more in recent years.

Prior Art However, ethylene-propylene copolymer rubber has several drawbacks compared to general diene rubbers. One of its drawbacks is workability. That is, in order to increase the mechanical strength of an ethylene-propylene copolymer, the copolymerization ratio of ethylene is usually increased. As the ethylene ratio increases, ethylene combines in blocks to form crystals. Since it is not possible to control the degree of ethylene blockiness by conventional polymerization methods, when producing an ethylene-propylene copolymer with a high ethylene content, a copolymer having a high degree of ethylene blockage is produced. Copolymers with such a high degree of ethylene block are very hard at room temperature or even lower temperatures. There are problems such as poor merging and the need for a lot of energy when rolling. In addition, ethylene-propylene copolymer rubber having a high degree of ethylene block as described above has significantly lower elasticity, which is an inherent characteristic of rubber, at low temperatures, and becomes resin-like. On the other hand, in order to eliminate these drawbacks, attempts have been made to lower the ethylene content ratio.

Although this method improves the processability as described above, it has the serious problem of lowering tensile strength, tearing strength, etc.

OBJECT OF THE INVENTION Based on the prior art described in 1--, an object of the present invention is to develop an ethylene-propylene copolymer rubber 11 that is excellent in both mechanical strength and processability.

Structure of the Invention The ethylene-propylene co-rl'I complex of the present invention is a novel ethylene-propylene diolefin characterized by having a controlled molecular structure and comprising ethylene-propylene diolefins satisfying the following (a) to (Hof). It can be defined as a propylene copolymer.

(a) Ethylene/propylene weight%: 80 to 40/
The ratio is from 20 to 60, and the bonding amount of diolefin units is from O to 50 in terms of iodine value.

(b) Maximum tensile stress of copolymer rubber at 25°C (
σ+oax) is 20-150 kgf/cm",
And the tensile stress (σ,...) at 100% elongation is 2
0 kgf/cm" or less.

(c) The content of propylene is C weight %. Ethylene-
Ratio of σmaX and σioo of propylene copolymer (σm
ax/σ100) is A, and A is larger than B given by the following formula.

B = -0,18C+ 10.5 C: Propylene content (wt%) (d) The cyclohexane insoluble content of the copolymer rubber at 30°C is 15 wt% or less.

(e) The melting heat amount of the crystal with a melting point of 0° C. is 6% or more of the total heat of fusion as determined by a differential scanning calorimeter.

Details of J (polymer rubber) of the present invention will be explained below.

(Chain structure) The ethylene-propylene copolymer rubber of the present invention has an ethylene chain controlled within a suitable range of 1F, and has only a few weak crystals under normal conditions, but when stress such as tension is applied. It is an ethylene-propylene copolymer rubber that exhibits so-called stretch crystallinity, which produces particularly strong crystals. In order to obtain an ethylene-propylene copolymer rubber with excellent mechanical strength and processability, which is the object of the present invention, many requirements are necessary. These will be explained one by one.

(Structural units) (1) The ethylene unit in the ethylene-propylene co-compounded rubber of the present invention is 80-40% by weight, preferably 75-45% by weight.
It is necessary to have a weight of % weight. When the ethylene unit exceeds 80% by weight, the ethylene chain becomes longer or
Even when the length is controlled to be constant, the amount of crystals in the copolymer rubber increases, resulting in a hard rubber.

Although such copolymer rubber has high mechanical strength such as tensile strength, it is hard at around room temperature or even lower temperatures, so it has poor processability, such as difficulty in biting with a kneading machine. It also becomes a so-called plastomer, which is a resin that does not lose the characteristics of a rubber elastic body. Since such rubber loses its rubber properties at low temperatures, it is judged to have poor low-temperature properties.

Conversely, when the ethylene content exceeds 40% by weight, not only the mechanical strength of raw rubber but also the mechanical strength of crosslinked rubber crosslinked with peroxide or sulfur, such as breaking stress,
Tensile strength, tear strength, etc. are insufficient.

Dicyclopentadiene is a diolefin.

Tricyclopentadiene, 5-methyl 2,5-norbornadiene, 5-methylene-2-norbornene, 5-ethylidene-2-norbornene, 5-isopropylidene-2
-norbornene, 5-isopropenyl-2-norbornene, 5-(]-butenyl)-2-norbornene, cyclooctadiene, vinylcyclohexene, 1,5.9-cyclododeca-1-lyene, 6-methyl-4,7, 8,9-
Tetrahydroindene, 2,2'-cyclopentenyl,
trans-1,2-divinylcyclobutane, 1゜4-hexane, 2-methyl-1,4-hexadiene, ],
6-octane, 1,7-octane, 1,8-nonadiene, 1,9-decadiene, 3,6-simethyl-1
, 7-octadiene, 4,5-dimethyl-1,7-octadiene, ].

There are 4,7-octatriene, 5-methyl-1,8-nonadiene, etc., and one type selected from these diolefins or a mixture of two or more types may be used. Among these diolefins, 5-ethylidene-2-norbornene and dicyclopentadiene are particularly preferred for economical reasons.

The copolymerized amount of diolefin can be used in an iodine value range of O to 50, preferably O to 35''lQ.

If the iodine value exceeds 50, problems will arise in terms of industrial production, such as a decrease in the polymerization yield of the copolymer rubber and a tendency to produce two-dimensionally crosslinked gels.

(Maximum tensile stress) (2) The maximum tensile stress (allilX) of copolymer rubber at 25°C is 20 to J50 Jf/(
:l11', &fpreferably, 2 (1= I I Ok
+; [/CIl+2 range, and] tensile stress ("+1111) at OO% elongation is 20 Jf/cm
It is 2 or more.

If the maximum tensile stress is less than 20 kgf/cJ, mechanical strength is insufficient. If it exceeds 150 kgf/al, a large amount of energy will be required during kneading, and additional problems such as deterioration of biting into the rolls will occur. 100
The tensile stress σzoo at the time of % elongation generally corresponds to the number of cyclohexene insolubles in the copolymer rubber, or the increase in hard crystals based on long chain bonds of ethylene. etc., it becomes larger. Based on these, the stress at 100% elongation needs to be 20 kHz/cm' or less, preferably 15 kgf/aJ or less. The stress at 100% elongation is 20 to 3f/a+! If it exceeds this, the copolymer rubber becomes resinous, the filler is poorly dispersed during kneading, the raw rubber remains in the kneading, and a lot of energy is required for heating in the next step of compounding step 11. In other words, it is judged that the workability is poor.

(Stretched crystallinity)) The propylene content in the ethylene-propylene copolymer Go 11 of the present invention is C weight %, and 0 m ax /σ13
．． .

When Δ is Δ, it is necessary that Δ is larger than the value of I obtained by the following equation.

+3 = -0,18C+IO,5 When 8 in -1- is smaller than 13, either the additive property or the mechanical strength is insufficient. For example, σm
ax and σ1°. If both are large and A is smaller than B, the mechanical strength will be high. Processability is poor at low temperatures. On the other hand, if σmax is small, σ,. . is small and 8 is smaller than B, sufficient mechanical strength such as tear strength cannot be obtained.

(Cyclohexane-insoluble content) (4) The cyclohexane-insoluble content of the copolymer rubber at 30°C is less than 15% by weight, preferably 10% by weight or less. Cyclohexane insoluble content is a long string of ethylene! lrt&I
This part is mainly made up of hard crystals based on 1-polymerization, which precipitates as insoluble matter. Cyclohexane insoluble [5
If it exceeds the weight percentage, the addition property is poor compared to the copolymer rubber of the present invention having the same composition.

(Heat of fusion) (5) The controlled molecular structure of the olefin copolymer rubber of the present invention can be measured by differential scanning calorimetry (DSC) analysis. The measuring method using DSC will be described later, but the shaded area in FIG. 1 shows weak crystals in which ethylene is moderately chained. The chain length of ethylene in this shaded area is ^, Peterlin et al. (J, Poly
mer Sci,, ^-2. ．． 6.587 (1968)
), it is thought to be around 10 to 20. When the chain length of ethylene becomes longer, the melting point of the crystal appears around 120°C.

In order to obtain rubber with excellent mechanical strength and processability, five steps must be taken.
The heat of fusion of crystals having a melting point of 0°C to 100°C must be 6% or more of the total heat of fusion. A copolymer having this value of less than 6% is inferior in mechanical strength, such as tear strength, as compared to the olefin copolymer rubber of the present invention having an equivalent composition. Furthermore, there are conventional polymers in which this value exceeds 6%. For example, the copolymer obtained by the method disclosed in Japanese Patent Publication No. 44-23812 has a higher maximum stress of raw rubber than the copolymer obtained by the conventional method, and the total melting heat of fusion in the region of 50°C to 100°C Although it is possible to obtain a copolymer rubber with a heat ratio of more than 6%, when compared with the copolymer rubber of the present invention which shows the same value, the ratio of 100°C obtained by DSC analysis is
It contains many hard crystals with a melting point higher than that, and there is also a large amount of cyclohexane insoluble matter. Therefore, there are differences such as poor processability near room temperature and at low temperatures, and it is clear that the rubber is different from the ethylene-propylene copolymer rubber of the present invention.

(Method for measuring heat of fusion with differential scanning calorimeter) The differential scanning calorimeter is DuPont Model 910 Differential Thermal Calorimeter (Differential T
herbal calorimeter) (DSC
) was used. The recorder was a DuPont 990 Thermal Analyzer.
zer) was used.

Sample amount is 20a+gf0.1'mg
26.9 mg of α-alumina (Shimadzu Corporation, standard sample for DSC) was used on the nce side.

(Measurement) The sample and Reference are placed in an aluminum holder (manufactured by DuPont) at room temperature, loaded into the DSC, and heated to +180°C. After that, 10℃ per minute
After cooling to -100°C at a rate of 100°C, analysis is performed at a heating rate of 20°C per minute. A typical SC thermograph obtained is shown in FIG.

(Calculation of heat of fusion) The total amount of crystals is the area surrounded by point P-R-3-T-V-U-P in Figure 1, and the amount of crystals at 50 to 100°C is R-8-V to U.
- The shaded area surrounded by R.

On the other hand, the amount of heat per unit chart area is calculated using indium (DuPont, standard sample for DSC) as a reference material.

The amount of each crystal is calculated as the amount of heat per gram of sample based on the amount of heat absorbed from indium. The heat of fusion of each is ΔHa (total), 6111 m (50 to 1
00°C). , Ili position was set as cal/g.

(Explanation of Fig. 1) In the thermogram as shown in Fig. 1 obtained with DSCiIllI constant, (1) From the tangent line of the baseline at -50℃ or less and the tangent line of thermogram t1, the first (i!I Score 0 points like this.

(2) Draw a perpendicular line from the 0 point and take the length h. h is determined by substituting the propylene content (% by weight) of the ethylene-propylene-diolefin copolymer into the following formula.

h=1. ++1XlO-2C+1.95S However, C is propylene content (wt%) S is DSC8I! The sample amount (eg) h used for the constant is the distance (mm) from the 0 point. (3) Draw a horizontal line at a point h away from the 0 point, and set the intersections with the 5 thermograms as two points.

(4) Draw a tangent from point p to the baseline of the thermogram above 140°C.

(5) Draw a perpendicular line to the points of +50℃ and 00℃ as shown in Figure 1, and insert the RS V U point.

(Tensile test of raw rubber t1) Raw rubber is made into a sheet of about 3 m/m with a hot roll at io0°C and formed into a sheet with a thickness of 2III11. This method uses a heat press at 150° C.], preheating for 5 minutes under a pressure of Okg/aJ, followed by pressing for 5 minutes at a pressure of 200 kg/cnf. Cool at 20°C for 15 minutes and remove from the press. During this period, the product was aged at 25° C. for 10 hours or more, and punched into a tanbell-type test J1 shown in FIG. 2 parallel to the crane direction using a hot roll.

These Danher type specimens are shown in Figure 1 and 4 (5 and 8).
) spacing is 64+wm. The interval between ■ and 5 (4 and 8) is 14
11111.The interval between 9 and 11 (10 and 12) is 5III
I11, the curve connecting 2 and 13 (3, 14.6, 15.7, and 16) is an arc with radius 6III11,
The curve connecting 9 and 13' (10 and 14, 11, 15, 12 and 16) is a circular arc with a radius of 4 mm. The gauge line when measuring elongation is 51 on both sides from the midpoint of the line connecting 1 and 4.
Let it be the line connecting 17 and 18 drawn at the position II11, and 19 and 20.

Based on the tensile test method of J' IS K-6:30], the temperature was 25°C and the tensile rate was 500III/
Measured at 111n. The stress at 100% elongation is σ□. . (kgf/Ca+'), and the maximum tensile stress up to breakage is a n+ax(k(Hf/cn
).

(Method for measuring cyclohexane insoluble content) Cut 3 g of raw rubber of copolymer rubber into pieces with a side length of 1 m or more, immerse them in 100 m of cyclohexane, and leave them in a constant temperature bath at 30°C for 48 hours. . Then weigh the 80 mesh stainless steel wire mesh (W,)
Filter with a wire mesh and reduce the pressure of 1 to 1 O-1n + mlB to
Dry under reduced pressure at 05°C for 1 hour. Weigh the wire mesh after drying -i+
tL (Wl), calculate the insoluble content using the following formula.

Wl: Weight of the wire mesh after drying and filtration Wo: Weight of the wire mesh before drying and filtration (Measurement method of other physical properties) Propylene content was measured using red, external absorption spectrum Diolefin content was measured by titration method .

The tensile stress, tensile strength, and tear strength of vulcanized rubber are determined by JIS.
Measured based on K-6301. The processability of the compounded rubber in the Banbury mixer was evaluated by visually observing the condition of the compounded rubber after being discharged from the Banbury mixer.

The mixing condition of the filler in the compounded rubber is graded as excellent, -good, -fair, and -poor in descending order of the glossiness of the surface of the compounded rubber.

The processability of compounded rubber in a roll mill is determined by rolling a 10-inch roll at a roll temperature of 50°C ± 5° (:, 211°C in the nip).
It was wrapped around a roll in III and evaluated based on the length of time required to wrap around tie 1- and whether or not the winding state was that it was wrapped around tie 1-. The result is that the time to wrap around tie 1 is short, and depending on the roll, tie 1 ~
It was ranked as excellent to fair to poor based on what was wrapped around it.

(Mooney viscosity) The Mooney viscosity of the copolymer rubber of the present invention is not limited as long as it satisfies the conditions set forth in the claims, but it generally has a Mooney viscosity of 20-350 at M'I+4+100C.
is within the range of A copolymer rubber having M'l+4+IoOc of more than 150 is often used as an oil-extended rubber by adding process oil or the like.

(11 Manufacturing method) The ethylene-propylene copolymer rubber of the present invention is composed of an organometallic compound of groups 1h to III of the periodic table and groups 1 to 1 of the periodic table.
It is produced using a catalyst consisting of a combination of a transition metal compound selected from Group (1) and Group (2).

As organometallic compounds, organic L1, @Na, organic,
An organic Al compound is used. Preferably it is an organic A1 compound. More preferably, a halogen fossil compound given by the following formula is preferred.

R3-mAIXm R represents an alkyl residue having 1 to 8 carbon atoms.

m ranges from 1.1 to 1.4, preferably from 1.15 to 1.25.

X represents halogen, preferably C1.

This A1 compound is obtained by mixing two or more types of organic Al compounds. As a specific combination, 1
- ethylaluminum and ethylaluminum dichloride, 1 to ethylaluminum and sesquiethylaluminum 11 chloride, diethylaluminium t1 chloride 1- and ethylaluminum dichloride, ethylaluminum 11 talolide and sesquiethylaluminum talolide 1-11 to liisof Examples include chillaluminum and sesquiethylaluminum talololyte 1-, rl-octylaluminum dichlorite and sif-sobutylaluminum dichlorite. There is no effect on the copolymer rubber due to the difference in the combination of 1), and it is necessary that the proportion of halogen be within the range of the formula.

If an organic All-I compound with m less than 1.1 is used, it is possible to produce copolymerized rubber 11 with high tensile strength of raw rubber, but the amount of cyclohexane insoluble matter increases, which makes it difficult to achieve the objective of the present invention. No polymer is obtained.

When m is larger than 1.4, the amount of cyclohexane insoluble matter decreases, but the tensile strength of the raw rubber decreases, making it impossible to obtain the copolymer of the present invention.

The transition metal compound is a catalyst component consisting of a combination of a vanadium compound and at least one or more compounds selected from transition metal compounds of groups 1 to 2 and group 2. In this case, the vanadium compound is vanadium oxytrichloride vOc1. , alkoxyhanadate, such as n-butylhexyvanadate VO (0-n-CdI2
)3, Isobutylhanadate VO (0-jsoC41t
g), Octylvanadate-1-VO (QCIIll,,
), etc., and VOC1a and saturated aliphatic alcohols having 1 to 2 carbon atoms, such as methyl alcohol, ethyl alcohol, propyl alcohol, butyl alcohol, pentyl alcohol, hexyl alcohol, octyl alcohol, etc. X4-mTi(OR)
Vanadium compounds such as a titanium compound represented by m, a zircon compound represented by
Chromium chloride, chromium acetylacetoner-1s Cr(A
cAc) a, chromium octoate Cr (C, If,
, C00), chromium compounds such as nickel octoate N1 (C71f□, C00), nickel naphthenate N
Examples include 1(Naph)z, cobalt octoate, and cobalt naphthenate. Preferably ■(AcAc)3
,X4-mT,l(OR)m,X4-mZr
(OR) m.

At this time, m is in the range of 0.5 to 3.5, and may be a mixture of two or more components within this range. Also, 0 is an alkoxy group having 1 to 2 carbon atoms, and X represents a halogen.

The composition ratio of the vanadium compound to the transition metal compound of groups 1 to 2 and group 2 is in the range of 1 to 1/2 (molar ratio), preferably 110.2 to /1.5 (molar ratio). is within the range of

The above catalyst system is
390, JP 45-3360, JP 51-6291
It is also possible to use activity enhancers such as perchlorocrotonic acid ester and 1-lichloroacetic acid ester, which are known from JP-A-56-30415 and the like.

-Using the catalyst system as described above, normal hexane is used as the polymerization solvent, and the polymerization temperature is -]O~+50℃, pressure 0~10K.
g/aJ range of ethylene/propylene/diolefin from 0.06 to 0, 25/0, 3 to 0.170 to
Contact is made at a molar ratio of 0.1.

Molecular weight can be adjusted using hydrogen gas.

(Applications) The copolymer rubber of the present invention can be used for bumpers, films, etc. by curing or blending with other olefin polymers or olefin copolymers. Copolymer, ethylene-vinyl acetate copolymer, butyl rubber, halogenated butyl rubber 11, natural rubber, polybutadiene rubber, polyisoprene rubber, styrene-butadiene rubber, acrylic acid polymer, polysiloxane, vinyl chloride polymer, chloroprene, acrylonitrile - A combination of butadiene copolymers, etc. or alone, conventional ethylene-propylene copolymer rubber, ethylene-propylene-diolefin copolymer Go t1, or carbon base J'-Number 2 with 10 α-olefins. It can be used in applications where basic copolymers such as ethylene-butene-1 copolymer, ethylene-butene-1-diolefin copolymer, etc. are used. In this case, if necessary, carbon blank, zinc white, extender oil, blowing agent and other fillers are blended (1), and peroxide-based and sulfur-based crosslinking agents are blended.

The ethylene-zolopyrene copolymer rubber of the present invention thus prepared can be used in various electrical materials such as waterproof sheets, various sponges, tubes, hoses, belts, and electric wires in an uncrosslinked state or in a crosslinked state. , anti-vibration go 1
Can be used for 1st prize.

EXAMPLES Next, the ethylene-propylene copolymer rubber of the present invention will be specifically explained with reference to Examples. However, the ethylene of the present invention
The propylene copolymer compound 11 is not limited to the examples listed above, as long as the limitations described in the claims are not exceeded.

Example-1 (Production of ethylene-zolopyrene copolymer) Volume 1i120
In a 0Q autoclave reactor, rl-hexane feed rate 80 Q/hr, residence time 0.75 hours, gas phase ethylene/propylene (molar ratio) 0.8.5-ethylidene-2 to norbornene (ENB) Supply amount 275cc/h
r, hydrogen concentration in the gas phase 4.2 mol%, as a polymerization catalyst,
Triisobutylaluminum 1. / Ethyl aluminum tips 11
3.5xlO-
"mol/Q hexane, oxo: 11A vanasiu 1
1 to 5.8 x 1. A reaction mixture of O-' mol/Q hexane, tetra-n-butyl titanate/titanium tetrachloride = 1/] was mixed with 2. The polymerization temperature was 32°C.

Continuous i (5 cycles were carried out under the conditions of a polymerization pressure of 6 k[/-]. A small amount of water was added as a reaction terminator to the polymerization liquid extracted from the reactor, and the solvent was expelled from the system by steam distillation. In the finishing step, Go 11 was dried.

The rubber properties of the obtained rubber are shown in Table 1.

A blend of the following formulation was made using this raw coco A1.

Polymer 100 Polymerization part 1 (ΔF? Carbon 67.5 n Stearic acid 1 Subbutton) 1v5 Naphthenic oil 35 That is, -1, using a BR type Banbury mixer, at 76 rpm for 4.5 minutes at 70°C. After kneading,
1,1-1-methylthiurat\1.5 parts of modisulfide, mercaptohenzothiazole Q, 5-tp parts, and sulfur], 5'IN? ! : part at 50℃L: ('
Mix on a 10-inch roll for 5 minutes. This u
The IF nip was 2 mn+, the roll rotation was 22/28+'pm for the front and rear rolls, respectively3, and the vulcanization conditions were 1
(5o''C530 minutes, +1 quality of the obtained vulcanizate is shown in Table 1.

Examples 2 to 1 In the method of Example 1, the ethylene/propylene ratio in the gas phase, catalyst, IζN +3 supply, and hydrogen supply V were changed to produce Examples 2 to 1 in Table 1. 1's I 1'' Go 1, this 11'?
Paraffin oil (]yco/
L/400: Tomi-1: @san Co., Ltd. R1) te 50
'=R part addition. Vulcanized rubber 11 was obtained using these raw materials 11 in the same manner as in Example 1. The properties of the five raw materials 11 and vulcanized materials 11 are shown in Table 1. In addition, in Table 1 (
) is the table.The value is the oil i;
shows the characteristics of

Comparative example-] to 2 [1-piece synthetic Gotz Co., Ltd. 1-piece IBM EJ+-/l
:3Q Comparative Example-1 and 1':P3F' manufactured by the same company were used as Comparative Example-2. Vulcanized rubber 11, Y by the method of Example-1 and 1iiJ? 1y ta, raw 11 and vulcanized 1
The characteristics of 1 are shown in Table 1.Comparative Example-; A vulcanized rubber was obtained in the same manner as in Example-1 using Go 11. The properties of raw rubber and vulcanized rubber 11 are shown in Table 1.

Comparative Example-6 EPDMET]96 manufactured by Nippon Synthetic Rubber Co., Ltd. was used. Vulcanized rubber 11 was obtained in the same manner as in Example-1. The properties of raw rubber and vulcanized rubber are summarized in Table-1. In Table 1, ()
The numerical values shown in the figure indicate the characteristics of the raw gogo 11 after the oil has been extracted.

, (Description of Examples) 1. Comparison of Example-1 and Comparative Example-1 ・In Comparative Example-1, the A value is lower than the B value, Δ)l+5(50-100) /
The value of ΔI1m(tol:al) is also small. Although Example-1 has a low specific hardness and excellent Banbury properties, it has poor windability around a roll and furthermore, the raw rubber has a low σl1ax.

It can be seen that tear strength and compression set at high temperatures are inferior.2.
Comparison of Example-2 and Comparative Example-2 Comparative Example-2 has a Δ value of β
value, and the proportion of heat of fusion between 50 and 100°C is also small. The copolymer rubber of Example-2 of the present invention, which satisfies 'I, and the copolymer rubber of Example-2 of the present invention in which '1 is almost the same, is compared to Comparative Example-1, Banbury, roll applied] bisexuality, tear strength (176t
bl.

;(, Example-3 and Comparative Examples-3 to 5 Comparative Example-: 1 has a large amount of cyclohexane insoluble matter, high hardness, and is inferior in abrasion resistance. Also, tear strength and compression set at low temperatures are poor.

Comparative Example-4 is σ□. . is high and the A elevation is lower than the B value.

Compared to Example-3, both mechanical strength and workability were poor.

In Comparative Example-5, σ1lIa× was too high, resulting in poor workability.

Effects of the Invention According to the present invention, there are provided ethylene-propylene copolymer rubber and ethylene-propylene-diene co-tft and synthetic rubber which are excellent in both mechanical strength and formability.

[Brief explanation of drawings]

FIG. 1 shows an example of a thermograph obtained by measurement using a differential scanning calorimeter, and FIG. 2 is a front view of a test piece used for measuring tensile stress. Applicant IJ Honsei Gol, Co., Ltd. Agent Minoru Isaka Procedural amendment dated July 2, 1980 Manabu Shiga, Commissioner of the Glaze Office 1 Indication of case 1989 Patent Application No. 1Q9385 2 Invention Name of ethylene-propylene copolymer rubber 3 Relationship with the case of the person making the amendment Patent applicant name Name Japan Synthetic Rubber Co., Ltd. 4 Agent address 1-21-11 Nishi-Shinbashi, Minato-ku, Tokyo 5 Date of amendment order Voluntary Number of inventions increased by amendment 6 0 fl) M:9Bj'lK Page 21, line 5 (7,)
r (C,H,,Coo)2J' (C7Has C
Correct as OO+2 J. (2) Change “32” from page 16, line 10 of the same book to r(+, 3
Correct with rJ.

Claims (1)

[Scope of Claims] A copolymer of ethyl-None and propylene or a polymer of ethylene, propylene and diolefin,
An ethylene-zoropylene copolymer which is characterized by satisfying all of the conditions (a) to (e) in (a) to (e) above. The φ quantity ratio is 80:20 to 40:60. and J (If the bonding amount of diolefin units in the polymer is expressed as an iodine value, the iodine value of the copolymer is -0 to 50. (B) The maximum tensile stress of the copolymer rubber at 25°C ( σmax
) is 20-20-15O/af, and the tensile stress (σ, .8) at ]OO% elongation is 20 kgf/- or less. (c) Let A be the ratio of σ1lIa and σ11111 (a wax/a son ) of the ethylene-propylene copolymer rubber, and A is larger than the B value obtained by lj from the following formula 6 H = -0,18 (: + 10.5 C: Propylene content (wt%) (d) The cyclohexane insoluble content of the copolymer rubber at 30°C is 15!Q% or less. (e) 50°C to 100 as determined by differential scanning calorimeter. The heat of decomposition of a crystal with a melting point of ℃ is 6% or more of the total heat of fusion.