JPS62256809A - Ethylene/alpha-olfein copolymer and its production - Google Patents

Abstract

PURPOSE:To obtain the title ethylene/alpha-olefin copolymer improved in an affinity for carbon black, carbon dispersibility, mechanical strength, kneading workability, rollability, etc., by introducing an Sn-C bond into an ethylene/alpha- olefin copolymer. CONSTITUTION:Ethylene (A) is copolymerized with a 3C or higher alpha-olefin (e.g., propylene) or/and a nonconjugated compound (B) (e.g., dicyclopentadiene) and an organotin compound (C) of the formula (wherein n is 1-4, R<1> is a 4-16C linear or cyclic alkenyl and R<2> is a 1-10C aliphatic or aromatic alkyl), e.g., 3-butenyltributyltin, in the presence of a Ziegler-Natta catalyst. In this way, the title copolymer comprising 20-85wt% component A, 80-15wt% component B and 0.007-5wt% component C and having a tin content of 0.005-0.5wt%, an iodine value of 0-60 and a number-average MW of 1,000-500,000 is obtained.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention relates to a novel ethylene-α-olefin copolymer and a method for producing the same, and more specifically relates to carbon dispersibility,
The present invention relates to an ethylene-α-olefin copolymer having excellent kneading workability and roll processability as well as excellent mechanical strength of vulcanized rubber, and a method for producing the same.

(Prior art) Ethylene-α-olefin copolymers do not contain double bonds in their main chains, so they have superior heat resistance, weather resistance, and ozone resistance compared to diene rubbers. It is widely used in fields where weather resistance is required.

However, ethylene-α-olefin copolymer elastomers generally have a lower affinity with carbon and poor carbon dispersibility than diene rubbers, resulting in poor kneading workability, roll processability, and mechanical strength. , its use was limited.

(Problems to be Solved by the Invention) It is an object of the present invention to eliminate the drawbacks of the prior art and to provide an ethylene-α-olefin system that has excellent carbon dispersibility, kneading workability, roll processability, and mechanical strength. An object of the present invention is to provide a method for producing a copolymer elastomer.

(Means for Solving the Problems) In order to achieve the above object, the present inventors have conducted intensive research and have developed an organic tin compound having at least one C═C bond and at least one 5n-C bond. A novel organotin compound-containing ethylene compound obtained by reacting ethylene and an α-olefin other than ethylene or/and a non-conjugated diene compound in the presence of a Ziegler-Natta catalyst.
It was discovered that an α-olefin copolymer elastomer has extremely excellent dispersibility of carbon black, and the present invention was achieved.

The present invention comprises: (1) 20 to 85% by weight of ethylene component units (A) and 1 α-olefin component unit having 3 or more carbon atoms (B)
5-80% by weight, non-conjugated diene compound component unit (C) 0
~20% by weight and the following general formula (I) Sn (R1)n (R2)<-n, (I)(
In the formula, n is an integer of 1 to 4, R1 is a straight or cyclic alkenyl group having 4 to 16 carbon atoms, and R2 is an aliphatic or aromatic alkyl group having 1 to 10 carbon atoms. Consisting of component unit (D) from 0.007 to 5% by weight, tin atom content from 0.005 to 0.5% by weight, iodine value from 0 to 60, and number average molecular weight from 1000 to 500.
．． 000 random ethylene-α-olefin copolymer.

In addition, the method for producing ethylene-α-olefin of the present invention involves adding ethylene, an α-olefin having 3 or more carbon atoms or/and a non-conjugated diene compound, and the organotin compound shown in the general formula (1) above to a Ziegler-Natta catalyst. It is characterized by polymerization in the presence of

The α-olefin used in the present invention is an α-olefin having 3 to 12 carbon atoms, such as propylene, butene-1
, 4-methylpentene-1, hexene-1, octene-
1st class is used. Among these compounds, propylene is particularly preferred. These α-olefins may be used alone or in combination of two or more.

Examples of non-conjugated diene compounds include dicyclopentadiene, tricyclopentadiene, 5-methyl-2,
5-norbornadiene, 5-methylene-2-norbornene, 5-ethylidene-2-norbornene, 5-isopropylidene-2-norbornene, 5-isopropenyl-2
- norbornene, 5-(1-butenyl)-2-norbornene, 5-vinylnorbornene, cyclooctadiene,
Vinylcyclohexene, 1,5.・9-cyclododecatriene, 6-methyl-4,7,8,9-tetrahydroindene, 2,2'-dicyclopentenyl, trans-1
, 2-divinylcyclobutane, 1,4-hexadiene,
2-methyl-1,4-hexadiene, 1,6-octadiene, 1,7-octadiene, 1,8-nonadiene, 1
．． 9-decadiene, 3,6-dimethyl-1,7-octadiene, 4,5-dimethyl-1,7-octadiene, 1
．． 4,7-octatriene, 5-methyl-1°8-nonadiene, etc. are used. Among these compounds, especially 5
-ethylidene-2-norbornene (ENB) and dicyclopentadiene (DCP) are preferred.

At least 1111i1 C═C bond represented by general formula (1) used in the present invention and at least one 5n
Examples of the organic tin compound having a -C bond include alkenyltrialkyltin, cycloalkenyltrialkyltin, bicycloalkenyltrialkyltin, etc.
For example, 3-butenyltributyltin (CH2=CH-(
CH2)2-3n(C4H9)3), 5-hexenyltributyltin (CH2=CH-(CH2)4-3n
(C4Hg)3), 7-octynyltributyltin (
CH2=CH-(CH2) 5-3n (C489)
3), 3-butenyltriphenyltin (CH2=CH
-(CH2) 2-3n (Cs H!) 3)
, 5-hexenyltriphenyltin (CH2=CH-(
CH2) 4-3n (C6Hh) 3), 7-
Octynyltriphenyltin (CH2=CH-(CH2
)6-3n (C6Hk)3), 5-cyclooctenyltributyltin 5-cyclooctenyltriphenyltinbicyclo(2,
2,1)-2-hebutenyltributyltinbicycloC2,2,1)-2-hebutenyltriphenyltinbisdicyclopentajenyldibutyltinbisdicyclopentadienyldiphenyltinbis[2-(bicyclo(
2,2,11-2-heptenylidene)ethyl]dibutyltinbis(2-bicyclo(2,'2,1)-2-hebutenylidene)ethyl]diphenyltindicyclopentagenyltributyltindicyclopentadienyltriphenyltin .

It is preferable that these organic tin compounds are used after being diluted in advance with the same or different solvent as the polymerization solvent described below.

Further, it is preferable to use monomers (a) to (C) that have been purified in advance using a molecular sheep or the like.

In the present invention, ethylene, an α-olefin having 3 or more carbon atoms or/and a non-conjugated diene, and (D) an organotin compound represented by general formula (1) are mixed in an inert polymerization solvent in the presence of a Ziegler-Natta catalyst. Polymerize to

The Ziegler-Natta catalyst used in the method of the present invention is
It is a combination of a transition metal compound of groups IVb to v'+b of the periodic table and an organometallic compound of group Ia-, group I1a- or ma- of the periodic table. The transition metal compounds used include halides of Ti, Zr, ■, and Cr, acetylacetone salts, and alcoholades, such as titanium tetrachloride (TiC14), titanium trichloride (TicJ3), titanium oxyacetylacetonate (TtO( acac)2), vanadium tetrachloride (V]!4), vanadium trichloride (VCl
2), vanadium oxychloride (■0Ci3), vanadium acetylacetonate (V (acac)3)
, vanadium oxyacetylacetonate (■○(ac
ac)z), vanadiram tetrabromide (■Br4)
, vanadium oxytryptoxide (VO(OC4H)
9) 3), Titanium tetrabutoxide (Ti(O
C4H9)4) etc. are used. Among these compounds, vanadium oxychloride (VOCl2), titanium tetrachloride (T i Cβ4), or mixtures of these compounds are particularly preferred. Also, as a transition metal compound, M gCjl! A two-carrier type Ti-based catalyst and a polar compound-modified (1)-based catalyst may also be used.

As the organometallic compound, Alz L 1% Mg
Alkyl compounds or halogenated alkyl compounds are used, such as trimethylaluminum (AJMe3)
, ) ethylaluminum (/IEt3), triisobutylaluminum (A#(i-Bu)3), diethylaluminum monochloride (AfEt2CA), ethylaluminum dichloride (Aj!EtC12), ethylaluminum sesquichloride (AIEtl)
, 3 C(11,3), etc. are used. Among these compounds, especially Al1Et 7. sClf, Js, AQE
Preference is given to t3, kl(iBu)3 or mixtures of these compounds.

These transition metal compounds and organometallic compounds are preferably used after being diluted in advance with the same or different solvent as the polymerization solvent described below.

The inert polymerization solvent used in the reaction system is an organic solvent that does not react with the Ziegler-Natta catalyst and is liquid under the reaction conditions, such as aliphatic paraffins having 4 to 8 carbon atoms (preferably n -hexane, n-hebutane)
, aromatic hydrocarbons (preferably benzene), saturated cyclic hydrocarbons (preferably cyclohexane, cyclohebutane), and the like. It is preferable to use these organic solvents that have been previously dehydrated and purified using a molecular sheep or the like.

When carrying out the method of the present invention, halogenated acetic esters such as ethyl trichloroacetate, butyl trichloroacetate, methyl dichloroacetate, etc. are used as polymerization activity improvers.
Butyl 1,1,2,3.3-pentachlorobutenoate, 1
, 1.2.3-Halogen-substituted butenoic acid esters such as ethyl tetrachlorobutenoate, halogen-containing organic compounds such as α, α, α-trichlorotoluene, hexachlorobutadiene, etc. can also be added.

The conditions for the polymerization reaction include a reaction temperature of -40 to 150°C;
Preferably, the temperature is 0 to 90°C, the reaction pressure is 0 to 20 atm, preferably 10 atm or less, and the reaction time is 5 minutes to 2 hours, preferably 20 minutes to 1 hour. The polymerization reaction is carried out using a stirring device, a temperature joint device, which can prevent the intrusion of external air (
It is carried out continuously or batchwise in a dry reactor having an inlet for supplying the polymers and catalysts of a) to (C) and an outlet for taking out the produced copolymer solution.

Hydrogen can also be used to control the molecular weight of the resulting copolymer.

The polymerization reaction is stopped by adding water or a compound having active hydrogen to the resulting copolymer solution to inactivate the catalyst.

In addition, as a method for coagulating the obtained copolymer, methods such as alcohol coagulation and steam stripping are used. As a method for drying the obtained copolymer, a known method such as a mechanical dryer can be used,
It is also possible to use a direct desolvation method that eliminates the coagulation step.

In the present invention, an ethylene-α-olefin-nonconjugated diene copolymer is produced in advance, and an organic tin compound having a 5n-H bond is reacted with the C=C bond of the nonconjugated diene component to form an organic tin. Compounds may also be introduced. In addition, after metalating hydrogen at the allylic position of the non-conjugated diene component using an alkyl compound such as Li or Mg, S n
An organic tin compound can also be introduced by reacting an organic tin compound having a -C1 bond (for example, dibutyltin dichloride, diphenyltin chloride, etc.). Furthermore, an organotin compound can also be introduced into the non-conjugated diene component using a metathesis catalyst.

Examples of organic tin compounds used in this case include tributylvinyltin, bis(trimethyltin)ethylene,
Examples include bis(triethyltin)ethylene and triphenylvinyltin. Examples of metathesis catalysts used include homogeneous and heterogeneous catalysts containing metals such as molybdenum, tungsten, and rhenium, and so-called Ziegler catalysts consisting of a combination of a transition metal compound and an alkyl aluminum, alkyl lithium, or alkyl magnesium. It will be done.

The ethylene-α-olefin copolymer elastomer produced by the present invention is a new compound, and the ethylene content in the copolymer is 20 to 85% by weight, preferably 25 to 8% by weight.
It is 0% by weight. When the ethylene content exceeds 85% by weight, crystallinity increases, temperature dependence increases, and cold resistance deteriorates, and when the ethylene content exceeds 20% by weight, mechanical strength becomes low.

Further, the iodine value regarding the content of non-conjugated diene in the copolymer is 0 to 60, preferably 0 to 45.

When the iodine value exceeds 60, ozone resistance is poor.

The content of tin atoms in the copolymer is Q,005-0.5% by weight, preferably 0.01-0.1% by weight.

When the content of tin atoms is less than 5% by weight of O and OO, the effect on improving carbon dispersibility is small, and when it exceeds 0.5% by weight, the mechanical strength becomes too low.

The number average molecular weight of the copolymer is 1000-500゜0OO1
Preferably it is 5000-100,000. If the number average molecular weight is less than 1000, it will not function as an elastomer, and if it exceeds 500,000, processability will be poor.

The copolymer obtained by the present invention includes ordinary natural rubber,
Compounding agents used in synthetic rubber (zinc oxide, carbon blank, white carbon, various clays, process oils, plasticizers, stabilizers, anti-aging agents, etc.) can be kneaded as needed, and include non-conjugated dienes. For copolymers, sulfur crosslinking, peroxide crosslinking, etc. can be performed, and for copolymers containing no non-conjugated diene, peroxide crosslinking can be performed.

(Effects of the Invention) According to the present invention, by introducing 5n-C bonds into the ethylene-α-olefin copolymer, the affinity with carbon black is increased, and the conventional ethylene-α-olefin copolymer is Compared to coalescence, carbon dispersibility and mechanical strength are improved, and kneading workability and roll workability are also improved. Therefore, the ethylene-α-olefin copolymer of the present invention can now be used in various rubber application fields that could not be used in the past, such as automotive hoses, automotive weather strips, tires, and waterproof sheets. ,
Useful for belts, electric wires, electrical parts, etc.

(Examples) Next, the present invention will be specifically explained with reference to Examples, but the present invention is not limited to the Examples unless it exceeds the scope of the claims.

In addition, % and parts in the examples are basically based on weight unless otherwise specified.

In addition, in the examples, various analysis methods and physical property measurement methods were in accordance with the following methods.

(1) Molecule fit (M n , M w , M w
/Mn) Measurement was performed as follows according to Takeuchi's Gel Permeation Curtain Graph (published by Maru@Co., Ltd.).

■ Standard polystyrene with known molecular weight (Toyo Soda Co., Ltd.)
The molecule LtM and its GPC (Gem Permeation Chr.
omatograph) count and draw a correlation diagram calibration curve of molecules iM and EV (Ej!ut ion Volume).

The concentration at this time is 0.02% by weight.

The standard polystyrene calibration curve is corrected to the EPDM calibration curve using the universal method.

(2) Obtain a GPC pattern of the sample using the GPC measurement method, and determine M using the above (2). The sample preparation conditions and G P C1ltl11 constant conditions at that time are as follows.

Sample preparation (a) O-dichlorobenzene solvent containing 2 as an anti-aging agent.
, 0.08% of 6-di-t-butyl-p-cresol is added and dissolved.

(b) Transfer the sample to an Erlenmeyer flask together with 0-dichlorobenzene solvent to a concentration of 0.1%.

(C) Heat the Erlenmeyer flask to 120°C, stir for about 60 minutes, and dissolve by 1/8.

(d) Subject the solution to GPC. Note that the sample is automatically filtered using a 0.5 μm sintered filter within the GPC device.

GPC measurement conditions (a) Equipment 3: 150C type (b) column manufactured by JJ aters; H manufactured by Toyo Soda Co., Ltd.
Type (C) Sample amount: SOOμ! (d) Temperature: 120°C (e) Flow rate: 1 mg/min (f) Column total theoretical plate number: 1 x 104 to 2 x 104 (value measured with acetone) (2) Sn content copolymer 100 was dissolved in 50 ml of toluene, and Zeeman・Effect Atomic Absorption Spectrophotometer (HITACHl 170-7
0 type), and add a tin standard solution for atomic absorption (1000p) in advance.
pm, Wako Pure Chemical Industries, Ltd.! ! The Sn content was determined using a calibration curve prepared by diluting I) with distilled water.

(3) Propylene content Measured by infrared absorption spectrum.

(4) Iodine value 11.Measurement by standard method.

(5) Tensile strength, elongation, tensile stress, hardness JIS K-
Measured based on 6301.

(6) Electrical resistance A sheet of vulcanized additive-free compound rubber with a thickness of approximately 2 mm is punched out into a disc shape of approximately 2.5 cm, with a radius of 1.1 cn+.
After applying lead paste to the surface of the circular part, the electrical resistance was measured using an electrical resistance measuring device (FLUKE 8050DA digital multimeter).

(7) Method for measuring tin atom content After making the copolymer into a film, it was formed into a 611 mφ disc shape, Ar pressure was 5xlO-6 Torr, output was 2'/X
After Ar etching at 20mA for 10 minutes, the degree of vacuum was 2.
．． 5X10'''77 o r r, output 8 KVx30
It was measured by a fluorescent X-ray method under mA conditions.

Example 1 Dehydrated and purified n-hexane 21 was charged into a 31 separable flask which had been replaced with N2 in advance, and purified ethylene gas, propylene gas and hydrogen gas were passed through a molecular sieve at a flow rate ratio of 6/4/2 (molar ratio). Phase feed and allow to dissolve for 10 minutes at room temperature with stirring.

Next, triphenyltin hydride and norbornadiene were added to this as organic tin compounds at 1/l (molar ratio).
n-hexane7p cloudy solution of bicyclo[2゜2.1]hebutenyltriphenyltin flQ,9 obtained by reaction with
mmo7! , A I E tl, g C1t, 55mm
ol and VOCj! 3 0.5 mmol was charged to start polymerization. While feeding ethylene gas, propylene gas, and hydrogen gas in the gas phase, the reaction temperature was set at 20°C, and the polymerization reaction was carried out at 1! I let it continue.

Thirty minutes after starting the polymerization, the catalyst was deactivated with isopropyl alcohol purified using a molecular sieve to stop the polymerization.

The obtained copolymer solution was added to methanol to precipitate it, and then dried with a heated roll at 100°C.

The yield of the obtained copolymer was 86 g, and the tin atom content was 0.06% by weight according to atomic absorption analysis of the copolymer after repeated reprecipitation purification with methanol.

In addition, the propylene content in the copolymer was determined by infrared spectroscopy.
Mn is 3.4 by GPC (gel perfusion chromatography method, solvent 0DCB) at 9% by weight and 120°C.
10,000, Mw was 175,000, and MY/Mn was 5.1.

FIG. 1 shows an analysis chart of the X-ray photoelectron spectrum of the obtained copolymer.

Comparative Example 1 The yield of a copolymer obtained by polymerizing in the same manner as in Example 1 except that no organotin compound was used was 95 g.

In addition, the propylene content in the copolymer was 36% by weight, and GPC
Mn is 19,000, MY is 173,000, M W /
Mn was 9.0.

Example 2 Bisbicyclo(2,2,l)-2-hepte-5-ethylidenyldiphenyltin obtained by metalating 5-ethylidene-2-norbornene with an alkyllithium as an organotin compound and then reacting it with diphenyltin chloride. lmm.

The yield of the copolymer obtained by polymerization in the same manner as in Example 1 was 90 g, and the tin atom content was 0.0.
It was 7% by weight. In addition, the propylene content in the copolymer is 31% by weight, the Mn by GPC is 23,000, and the MW is 19.
．． 10,000, and Mw/Mn was 8.3.

Example 3 2.5 mmol of 5-ethylidene-2-norbornene was added before the start of polymerization, after 5 minutes, after 10 minutes, and after 15 minutes, respectively.
The yield of the copolymer obtained by the same polymerization treatment as in Example 1 was 83 g, and the content of tin atoms was 0.
It was 0.8% by weight. Further, the propylene content in the copolymer was 28% by weight, the iodine value was 4.5, the Mn by CPC was 29,000, the MW was 202,000, and the Mw/Mn was 7.0.

Example 4 In Example 1, triphenyltin hydride and dicyclopentadiene were mixed at 1/1 (
A copolymer was obtained in the same manner as in Example 1, except that dicyclopentadienyltriphenyls':):'l m moβ was used. The yield of the obtained copolymer was 71 g, and the Sn content of the copolymer was 0.1
6ffi (2%, propylene content is 32%, GPC
Mn is 20,000, Mw is 21.3 swords, Mw /
Mn was 10.7.

Example 5 In Example 1, triphenyl hydride and 5-ethylidene-2-norbornene were used as organotin compounds at 1
/l (molar ratio) using 2-(bicyclo[2,2,1)-2-heptenylidene)ethyltriphenyl:XQ, 5 mmo 1, ethylene gas, propylene gas and hydrogen gas 6/410.
A copolymer was obtained in the same manner as in Example 1 except that the feed was carried out at a flow rate of 4 (molar ratio). The yield of the obtained copolymer was 93 g, the Sn content of the copolymer was 0.03% by weight, the propylene content was 30% by weight, the Mn by GPC was 104,000, the MW was 445,000, and the Mw /Mn was 4.3.

Example 6 A copolymer was obtained in the same manner as in Example 1 except that the flow ratio of ethylene gas, propylene gas, and hydrogen gas was changed to 515/1 (molar ratio). The yield of the obtained copolymer was 83g, and the Sn content of the copolymer was 0.
06fi amount%, propylene content is 43% by weight, Mn by GPC is 32,000, MW is 160,000, M w /
Mn was 5.0.

Comparative Example 2 A copolymer obtained by polymerizing in the same manner as in Comparative Example 1 except that 2.5 mmoj2 of 5-ethylidene-2-norbornene was added before the start of polymerization, 5 minutes later, 10 minutes later, and 15 minutes later. The yield of polymer was 96 g. In addition, the propylene content in the copolymer is 34% by weight, the iodine value is 5.1, and the G
Mn by PC is 3゜10,000, Mw is 186,000, Mw
/Mn was 6.1.

Test Example 1 The copolymers obtained in Examples 1 to 3 and Comparative Examples 1 to 2 were kneaded for 5 minutes in a 250 ml Labo Plastomill according to the formulation shown in Table 1, and the electrical resistance of the resulting mixture was determined. It was measured. The results are shown in Table 2.

The results in Table 1 and Table 2 show that the copolymer obtained by copolymerizing an organotin compound according to the present invention is different from ordinary ethylene-propylene copolymer (Comparative Example 1) and ethylene-propylene non-conjugated diene. It showed a higher electrical resistance than the copolymer rubber (Comparative Example 2), indicating good carbon dispersibility. Further, in the case of the present invention, roll processability was also excellent.

Test Example 2 Dicumyl peroxide 3 g/100 g as a crosslinking agent was added to the compounded rubber obtained in Test Example 1: #l: Polymer, sulfur 0.3 g/100 g as a crosslinking aid)'-m combination was rolled into a roll. Press vulcanization was carried out at 160° C. for 35 minutes, and the physical properties of the obtained vulcanizate were evaluated.

The results are shown in Table 3.

Table 3 (Note) M+oo (kgf /c+j): Tensile stress (100% Modulus) Eb (%): Elongation at Break) (sJ
IS-8: Hardness (llardness) Table 3 shows that the copolymer obtained by copolymerizing an organic tin compound according to the present invention has a mechanical strength higher than that of a normal ethylene-propylene copolymer (Comparative Example 1). It shows that it is significantly superior.

[Brief explanation of drawings]

FIG. 1 shows the xpS (X
FIG. 2 is a diagram showing an analysis chart of a line photoelectron spectrum.

Claims (2)

[Claims] (1) Ethylene component unit (A) 20-85% by weight, α-olefin component unit having 3 or more carbon atoms (B) 15-80% by weight, non-conjugated diene compound component unit (C) 0-20% by weight, and the following: General formula (I) Sn(R^1)n(R^2
)_4_-_n(I) (where n is an integer from 1 to 4, R
^1 is a linear or cyclic alkenyl group having 4 to 16 carbon atoms, R^2 is an aliphatic or aromatic alkyl group having 1 to 10 carbon atoms) Organotin compound component unit (D) 0.0
07 to 5% by weight, and the tin atom content is 0.
．． 005 to 0.5% by weight, the iodine value is 0 to 60,
A random ethylene-α-olefin copolymer having a number average molecular weight of 1,000 to 500,000. (2) Ethylene, an α-olefin having 3 or more carbon atoms or/and a non-conjugated diene compound, and the following general formula (I
) Sn(R^1)n(R^2)_4_-_n(I)(n
is an integer of 1 to 4, R^1 is a linear or cyclic alkenyl group having 4 to 16 carbon atoms, and R^2 is an aliphatic or aromatic alkyl group having 1 to 10 carbon atoms). - A method for producing an ethylene-α-olefin copolymer, which comprises carrying out a polymerization reaction in the presence of a Natta catalyst.