阅读说明：本技术 一种长链支化乙丙橡胶及制备方法 (Long-chain branched ethylene propylene rubber and preparation method thereof ) 是由 吴一弦 周百青 张树 郝小飞 于 2019-11-25 设计创作，主要内容包括：本发明属于高分子聚合物领域,涉及一种长链支化乙丙橡胶及制备方法。所述长链支化乙丙橡胶包括乙烯结构单元、丙烯结构单元和含乙烯基的非共轭二烯结构单元；其中,以所述长链支化乙丙橡胶的质量为基准,所述乙烯结构单元的质量含量为30.0wt％～78.0wt％,所述丙烯结构单元的质量含量为10.0wt％～55.0wt％,所述含乙烯基的非共轭二烯结构单元的质量含量为10.1wt％～40.0wt％。本发明可以大幅度提高含乙烯基的非共轭二烯单体的插入率及支化度,得到高侧链乙烯基含量、高支化度、低凝胶含量甚至无凝胶的长链支化乙丙橡胶,显著提高产品质量和性能,并降低生产成本。(The invention belongs to the field of high molecular polymers, and relates to long-chain branched ethylene propylene rubber and a preparation method thereof. The long-chain branched ethylene-propylene rubber comprises an ethylene structural unit, a propylene structural unit and a non-conjugated diene structural unit containing vinyl; wherein the mass content of the ethylene structural unit is 30.0 wt% -78.0 wt%, the mass content of the propylene structural unit is 10.0 wt% -55.0 wt%, and the mass content of the vinyl-containing non-conjugated diene structural unit is 10.1 wt% -40.0 wt% based on the mass of the long-chain branched ethylene-propylene rubber. The invention can greatly improve the insertion rate and the branching degree of the non-conjugated diene monomer containing vinyl, obtain the long-chain branched ethylene-propylene rubber with high side chain vinyl content, high branching degree, low gel content and even no gel, obviously improve the quality and the performance of products and reduce the production cost.)

1. The long-chain branched ethylene-propylene rubber is characterized by comprising an ethylene structural unit, a propylene structural unit and a non-conjugated diene structural unit containing vinyl; wherein, based on the mass of the long-chain branched ethylene propylene rubber,

the mass content of the ethylene structural unit is 30.0 wt% -78.0 wt%, preferably 35.0 wt% -75.0 wt%, and more preferably 40.0 wt% -70.0 wt%;

the mass content of the propylene structural unit is 10.0 wt% -55.0 wt%, preferably 15.0 wt% -50.0 wt%, and more preferably 18.0 wt% -45.0 wt%;

the mass content of the vinyl group-containing nonconjugated diene structural unit is 10.1 wt% to 40.0 wt%, preferably 10.1 wt% to 35.0 wt%, and more preferably 10.1 wt% to 30.0 wt%; the molar content of the vinyl group-containing nonconjugated diene structural unit is 2.1 to 14.0 mol%, preferably 2.3 to 12.0 mol%, and more preferably 2.5 to 10.0 mol%.

2. Long-chain branched ethylene-propylene rubber according to claim 1,

the gel content of the long-chain branched ethylene-propylene rubber is less than 1.0%, more preferably less than 0.8%, and still more preferably less than 0.6%;

the delta tan delta value for representing the long-chain branching degree of the long-chain branched ethylene propylene rubber is 0.01-0.40, more preferably 0.02-0.30, and even more preferably 0.03-0.15.

3. Long-chain branched ethylene-propylene rubber according to claim 1 or 2, wherein the vinyl-containing non-conjugated diene building blocks are derived from a vinyl-containing non-conjugated diene, preferably a vinyl-containing cyclic olefin, further preferably selected from the group consisting of 5-vinyl-2-norbornene, 5-allyl-2-norbornene, 6-methyl-5-allyl-2-norbornene, 5- (3-butenyl) -2-norbornene, 5- (3-butenyl-2-methyl) -2-norbornene, 5- (4-pentenyl) -2-norbornene, 5- (5-hexenyl) -2-norbornene, 5- (3-hexenyl) -2-norbornene, poly (vinyl-co-vinyl-containing) cyclic olefin, At least one of 5- (6-heptenyl) -2-norbornene, 5- (7-octenyl) -2-norbornene, 4- (4-pentenyl) -1-cyclohexene, 3-vinyl-6-methyl-1-cyclohexene, 3-vinyl-1-cyclopentene, 4-vinyl-1-methyl-1-cyclohexene, 4-vinyl-4-methyl-1-cyclohexene, 4-vinyl-1, 4-dimethyl-1-cyclohexene, 4-vinyl-1-cyclohexene and 4-allyl-1-cyclohexene, further preferred is at least one selected from the group consisting of 5-vinyl-2-norbornene, 5-allyl-2-norbornene, 6-methyl-5-allyl-2-norbornene, 5- (3-butenyl) -2-norbornene, 5- (3-butenyl-2-methyl) -2-norbornene, 5- (4-pentenyl) -2-norbornene, 5- (5-hexenyl) -2-norbornene, 5- (6-heptenyl) -2-norbornene and 5- (7-octenyl) -2-norbornene.

4. The preparation method of the long-chain branched ethylene propylene rubber is characterized by being carried out in the presence of a vanadium catalyst, wherein the vanadium catalyst comprises the following components:

and (2) component A: a main catalyst selected from the general formula VOCl₂OR¹And VOCl (OR)¹)(OR²) At least one of the vanadium-containing compounds shown in the specification, wherein R¹And R²Are the same or different and are each independently selected from C₁～C₁₀Alkyl of (C)₁～C₁₀Halogenoalkyl of, C₃～C₁₀Cycloalkyl of, C₃～C₁₀Halogenocycloalkyl or C₆～C₂₅Aryl of (a);

and (B) component: a cocatalyst which is an organoaluminum compound; and the number of the first and second groups,

optional component C: an activator having an oxidizing property to oxidize vanadium suboxides to vanadium higher oxides;

the preparation method comprises the following steps:

(1) mixing one of the component A and the component B with a monomer and a reaction medium, and then mixing with the other of the component A and the component B;

(2) optionally, adding component C into the system obtained in the step (1);

(3) carrying out polymerization reaction on the system to obtain the long-chain branched ethylene propylene rubber;

the monomer comprises ethylene, propylene and non-conjugated diene containing vinyl, and the amount of each monomer is such that the mass content of the ethylene structural unit in the long-chain branched ethylene-propylene rubber obtained by polymerization is 30.0-78.0 wt%, preferably 35.0-75.0 wt%, and most preferably 40.0-70.0 wt% based on the mass of the long-chain branched ethylene-propylene rubber; the mass content of the propylene structural unit is 10.0 wt% -55.0 wt%, preferably 15.0 wt% -50.0 wt%, and most preferably 18.0 wt% -45.0 wt%; the mass content of the vinyl group-containing nonconjugated diene structural unit is 10.1 to 40.0 wt%, preferably 10.1 to 35.0 wt%, and more preferably 10.1 to 30.0 wt%; the molar content of the vinyl group-containing nonconjugated diene structural unit is 2.1 to 14.0 mol%, preferably 2.3 to 12.0 mol%, and more preferably 2.5 to 10.0 mol%.

5. The method of claim 4, wherein R¹And R²Each independently selected from the group consisting of methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, 2-dichloro-1-ethyl, 1-dichloro-2-propyl, 1-dichloro-2-methyl-2-propyl, 3-dichloro-1-propyl, 2-dichloro-1-propyl, 1-dichloro-2-butyl, 3-dichloro-1-butyl, 2-dichloro-1-butyl, 1-dichloro-2-pentyl, 2-dichloro-1-pentyl, 1-dichloro-2-hexyl, 2-dichloro-1-hexyl, 2, 2-trichloro-1-ethyl group, 3,3, 3-trichloro-1-propyl group, 1,1, 1-trichloro-2-methyl-2-propyl group, 1,1, 1-trichloro-2-butyl group, 1,1, 1-trichloro-2-methyl-2-butyl group, p-methylphenyl group, 2-ethylphenyl group, 4-ethylphenyl group, 2-isopropylphenyl group, 2-tert-butylphenyl group, 2-sec-butylphenyl group, 2, 4-dimethylphenyl group, 2, 6-dimethylphenyl group, 2,3, 4-trimethylphenyl group, 2,3, 5-trimethylphenyl group, 2,3, 6-trimethylphenyl group, 2-trichloro-2-propyl group, 1,1, 1-trichloro-2-methyl-2-butyl, 2,4, 6-trimethylphenyl group, 2, 4-diethylphenyl group, 2, 6-diethylphenyl group, 2,4, 6-triethylphenyl group, 2, 3-di-t-butylphenyl group, 2, 4-di-t-butylphenyl group, 2, 5-di-t-butylphenyl group, 2, 6-di-t-butylphenyl group, 2,3, 4-tri-t-butylphenyl group, 2,3, 5-tri-t-butylphenyl group, 2,3, 6-tri-t-butylphenyl group, 2,4, 6-tri-t-butylphenyl group, 2, 6-di-t-butyl-4-methylphenyl group, 4-t-pentylphenyl group, 3-pentadecylphenyl group and 4-t-octylphenyl group.

6. The process according to claim 4, wherein the cocatalyst is an organoaluminum compound selected from an alkylaluminum, an alkylaluminum halide or a mixture thereof;

the alkylaluminum and alkylaluminum halide are preferably of the formula R_mAlX_3-mWherein R is C₁～C₁₀Alkyl of (C)₃～C₁₀Cycloalkyl of, C₇～C₁₀Aralkyl or C₆～C₁₀Each R may be the same or different, X is halogen, preferably Cl or Br, more preferably Cl, m is 1, 1.5, 2 or 3;

the alkylaluminum is preferably at least one selected from the group consisting of trimethylaluminum, triethylaluminum, tri-n-propylaluminum, triisopropylaluminum, tri-n-butylaluminum, triisobutylaluminum, tri-n-pentylaluminum, tri-n-hexylaluminum and tricyclohexylaluminum;

the alkylaluminum halide is preferably at least one selected from the group consisting of dimethylaluminum monochloride, diethylaluminum monochloride, di-n-butylaluminum monochloride, diisobutylaluminum monochloride, methylaluminum dichloroide, ethylaluminum dichloroide, n-butylaluminum dichloroide, isobutylaluminum dichloroide, methylaluminum sesquichloride, ethylaluminum sesquichloride, n-butylaluminum sesquichloride and isobutylaluminum sesquichloride;

the activating agent is selected from C containing 2-5 chlorine atoms₁～C₂₀And/or C containing 2 to 5 chlorine atoms₂～C₂₀An ester of (a).

7. The production method according to claim 4, wherein the molar ratio of component B in terms of Al element to component A in terms of V element is 5 to 35: 1, preferably 7-30: 1, more preferably 10 to 25: 1;

the molar ratio of the component C to the component A calculated by the element V is 0-6: 1, preferably 0 to 5: 1, more preferably 0 to 4: 1.

8. the process according to claim 4, wherein the non-conjugated diene is a vinyl-containing cyclic olefin, preferably selected from the group consisting of 5-vinyl-2-norbornene, 5-allyl-2-norbornene, 6-methyl-5-allyl-2-norbornene, 5- (3-butenyl) -2-norbornene, 5- (3-butenyl-2-methyl) -2-norbornene, 5- (4-pentenyl) -2-norbornene, 5- (5-hexenyl) -2-norbornene, 5- (6-heptenyl) -2-norbornene, 5- (7-octenyl) -2-norbornene, and mixtures thereof, 4- (4-pentenyl) -1-cyclohexene, 3-vinyl-6-methyl-1-cyclohexene, 3-vinyl-1-cyclopentene, 4-vinyl-1-methyl-1-cyclohexene, 4-vinyl-4-methyl-1-cyclohexene, 4-vinyl-1, 4-dimethyl-1-cyclohexene, 4-vinyl-1-cyclohexene and 4-allyl-1-cyclohexene, further preferably selected from 5-vinyl-2-norbornene, 4-allyl-1-cyclohexene, and mixtures thereof, At least one of 5-allyl-2-norbornene, 6-methyl-5-allyl-2-norbornene, 5- (3-butenyl) -2-norbornene, 5- (3-butenyl-2-methyl) -2-norbornene, 5- (4-pentenyl) -2-norbornene, 5- (5-hexenyl) -2-norbornene, 5- (6-heptenyl) -2-norbornene and 5- (7-octenyl) -2-norbornene.

9. The preparation method according to claim 4, wherein the total concentration of the monomers in the system is 10g/L to 180g/L, preferably 20g/L to 150g/L, and more preferably 30g/L to 120 g/L;

the molar ratio of component A to monomer, calculated as element V, is 1.0X 10^-4～5.0×10^-3: 1, preferably 3.0X 10^-4～4.0×10^-3: 1, more preferably 5.0X 10^-4～3.0×10^-3：1；

The polymerization reaction is adiabatic polymerization reaction or constant-temperature polymerization reaction;

the temperature of the polymerization reaction is-60 ℃ to 55 ℃, preferably-55 ℃ to 50 ℃, and more preferably-50 ℃ to 45 ℃;

the time of the polymerization reaction is 1 minute to 2 hours, preferably 2 minutes to 1.5 hours, and more preferably 2.5 minutes to 1.2 hours;

the reaction medium is selected from C₃～C₁₀Saturated alkane of (C)₃～C₁₀Cycloalkane of (2)₆～C₁₀At least one aromatic hydrocarbon.

10. A long chain branched ethylene propylene rubber obtainable by the process of any one of claims 4 to 9.

Technical Field

The invention belongs to the field of high molecular polymers, and particularly relates to long-chain branched ethylene-propylene rubber and a preparation method thereof, and more particularly relates to long-chain branched ethylene-propylene rubber with a side chain containing vinyl, a preparation method of the long-chain branched ethylene-propylene rubber, and the long-chain branched ethylene-propylene rubber with high side chain vinyl content and high branching degree prepared by the method.

Background

The main chain of the ethylene propylene rubber does not contain double bonds, has excellent heat resistance and aging resistance, and can be widely used for manufacturing automobile parts, wire and cable sheaths, building waterproof materials, resin modifiers and the like. The long-chain branched ethylene-propylene rubber obtained by introducing a long-chain branched structure on the molecular chain of the ethylene-propylene rubber has better processing performance. Meanwhile, in the preparation process of the polymer, the glue solution viscosity of the long-chain branched ethylene propylene rubber is low, the monomer concentration of a polymerization system can be further improved, and the production efficiency is improved. When the ethylene propylene rubber is mixed with carbon black, compared with linear ethylene propylene diene monomer, the long-chain branched ethylene propylene rubber can reach high dispersion degree in a shorter time, so that the processing time is shortened, and the processing efficiency is improved.

In order to enable vulcanization crosslinking, a non-conjugated diene is usually added as a third monomer in the copolymerization of ethylene and propylene, and a double bond is introduced into a side chain of the polymer. Furthermore, the ethylene-propylene rubber can be functionalized by reaction of the double bonds. At present, the non-conjugated diene commonly used as a third monomer in the industrial ethylene propylene diene monomer product mainly comprises Ethylidene Norbornene (ENB), dicyclopentadiene (DCPD) and 1, 4-hexadiene, and the common point of the monomers is that the monomers contain two double bonds, wherein one double bond can participate in coordination polymerization reaction of ethylene/propylene, so that the third monomer enters a main chain of a polymer, and the other double bond does not participate in coordination polymerization reaction of ethylene/propylene and is reserved on a side chain of the polymer for vulcanization crosslinking and functionalization reaction. However, the residual double bonds which do not participate in the polymerization reaction have low reactivity, resulting in a relatively slow vulcanization rate of the ethylene-propylene rubber. Vinyl Norbornene (VNB) is a precursor of Ethylidene Norbornene (ENB), the VNB is lower in price, if the VNB is introduced into an ethylene propylene diene monomer polymer as a third monomer, namely the VNB contains two double bonds capable of participating in coordination polymerization reaction, the double bond on one active ring participates in the coordination polymerization reaction, a vinyl with high reaction activity is introduced into a side chain, and meanwhile, the double bond part of the other relatively inactive vinyl can be subjected to copolymerization reaction to form a long-chain branched structure, so that the vulcanization speed and the functionalization reaction efficiency of the ethylene propylene rubber can be greatly improved, and the ethylene propylene rubber has the excellent performances of high vulcanization speed, high processing efficiency, low glue solution viscosity, easiness in functionalization and the like. However, at the same time, there are problems of low side chain vinyl content and high gel content of the product. In order to solve such technical problem, at present, there are two solutions in the prior art: firstly, the quaternary long-chain branched ethylene-propylene rubber (see WO2005090418A, US 2015/0087766) with vinyl contained in a side chain is synthesized by a method of copolymerizing ethylene, propylene, Ethylidene Norbornene (ENB) and Vinyl Norbornene (VNB), a long-chain branched structure is generated by the VNB, and a vulcanization crosslinking point is generated by the ENB, so that the problems of low vulcanization speed and high ENB price of the ethylene-propylene rubber cannot be solved; secondly, the ethylene, propylene and VNB copolymerization method is used for synthesizing the ethylene-containing side chain ternary long-chain branched ethylene-propylene rubber, such as: the VNB content of the ethylene/propylene/VNB ternary long-chain branched ethylene-propylene rubber prepared by the metallocene catalyst is lower than 10 wt%, see CN106699949A, CN101326204A and US20160355622, and when the VNB content is higher, gel is generated (see CN 101326204A); when a Ziegler-Natta vanadium catalyst is used for catalyzing the copolymerization of ethylene/propylene/VNB, because two double bonds in VNB are easy to polymerize, the ethylene-propylene rubber with high VNB content is difficult to prepare, and gel is often generated in the polymerization process; patent US2015/0087766 discloses a process for the preparation of ethylene/propylene/ENB/VNB copolymers with VNB content not exceeding 5% by weight, with Δ tan δ, representing the degree of long chain branching, higher than 0.15 and a low degree of long chain branching, using Ziegler-Natta vanadium based catalysts; patent US 6806336 discloses a method for preparing an ethylene/propylene/VNB copolymer with high VNB content using a Ziegler-Natta vanadium based catalyst, in order to prevent double bonds at the 5-position in VNB from participating in the polymerization reaction to produce gel, VNB is added in the method at the later stage of the polymerization reaction when the concentration of the catalyst is reduced, the VNB content in the ethylene-propylene-VNB copolymer actually prepared in the examples is only 0.42 to 1 wt%, and furthermore, VNB is added at the later stage of the reaction, so that VNB is not uniformly distributed on the polymer molecular chain, and the viscosity of the system at the later stage of the reaction is large, which affects the increase of the entire VNB content and the generation of a branched structure. However, the ethylene/propylene/VNB ternary long-chain branched ethylene-propylene rubber reported at present has the bottleneck problems of low side chain vinyl content, low long-chain branching degree and high gel content.

Therefore, it is highly desirable to develop a long-chain branched ethylene-propylene rubber with high side chain vinyl content, high branching degree and low gel content and a preparation method thereof.

Disclosure of Invention

The invention aims to provide long-chain branched ethylene-propylene rubber with high side chain vinyl content, high branching degree and low gel content and a preparation method thereof. The invention adopts a specific vanadium catalyst to control the reaction of vinyl in VNB monomers, not only can obtain long-chain branched ethylene-propylene rubber, but also is not easy to crosslink, thereby obtaining the long-chain branched ethylene-propylene rubber with high side chain vinyl content, high long-chain branching degree, low gel content and even no gel. The long-chain branched ethylene-propylene rubber provided by the invention has high reactive vinyl content in the side chain, and can greatly improve the vulcanization speed and the functionalization reaction efficiency of the ethylene-propylene rubber. Therefore, the long-chain branched ethylene propylene rubber provided by the invention has the excellent performances of high vulcanization rate, high processing efficiency, low glue solution viscosity, easiness in functionalization and the like.

In order to achieve the above object, a first aspect of the present invention provides a long-chain branched ethylene-propylene rubber comprising ethylene structural units, propylene structural units, and non-conjugated diene structural units containing a vinyl group; wherein, based on the mass of the long-chain branched ethylene propylene rubber,

the mass content of the ethylene structural unit is 30.0 wt% -78.0 wt%, preferably 35.0 wt% -75.0 wt%, and more preferably 40.0 wt% -70.0 wt%;

the mass content of the propylene structural unit is 10.0 wt% -55.0 wt%, preferably 15.0 wt% -50.0 wt%, and more preferably 18.0 wt% -45.0 wt%;

the mass content of the vinyl group-containing nonconjugated diene structural unit is 10.1 to 40.0 wt%, preferably 10.1 to 35.0 wt%, and more preferably 10.1 to 30.0 wt%; the molar content of the vinyl group-containing nonconjugated diene structural unit is 2.1 to 14.0 mol%, preferably 2.3 to 12.0 mol%, and more preferably 2.5 to 10.0 mol%.

According to the present invention, it is further preferred that the long chain branched ethylene-propylene rubber has a viscosity average molecular weight of 1.0X 10⁴g·mol^-1～7.0×10⁵g·mol^-1。

According to the present invention, it is further preferred that the gel content of the long-chain branched ethylene-propylene rubber is less than 1.0%, further preferred less than 0.8%, more preferred less than 0.6%.

According to the invention, the delta tan delta value for representing the long-chain branching degree of the long-chain branched ethylene-propylene rubber is further preferably 0.01-0.40, preferably 0.02-0.30, and more preferably 0.03-0.15. The difference in tangent values of loss angle at 0 ℃ and 100 ℃ of long-chain branched ethylene-propylene rubber (tan delta) can be used to characterize the magnitude of the long-chain branching (as described according to document CN 106699949A), the greater the tan delta value, the lower the long-chain branching. In the invention, the tan delta values of the long-chain branched ethylene-propylene rubber at different temperatures are measured by a Dynamic Mechanical Analyzer (DMA), and the tan delta value at 100 ℃ is subtracted from the tan delta value at 0 ℃ to obtain the tan delta. For comparison, the linear ethylene-propylene rubber has a Δ tan δ value of 0.92 (see comparative example 1).

In the present invention, the vinyl group-containing nonconjugated diene structural unit is derived from a vinyl group-containing nonconjugated diene, and the vinyl group-containing nonconjugated diene is preferably a vinyl group-containing cyclic olefin, and more preferably selected from the group consisting of 5-vinyl-2-norbornene (VNB), 5-allyl-2-norbornene, 6-methyl-5-allyl-2-norbornene, 5- (3-butenyl) -2-norbornene, 5- (3-butenyl-2-methyl) -2-norbornene, 5- (4-pentenyl) -2-norbornene, 5- (5-hexenyl) -2-norbornene, 5- (6-heptenyl) -2-norbornene, 5- (3-butenyl-2-methyl) -2-norbornene, 5- (4-pentenyl) -2-norbornene, 5- (5-, 5- (7-octenyl) -2-norbornene, 4- (4-pentenyl) -1-cyclohexene, 3-vinyl-6-methyl-1-cyclohexene, 3-vinyl-1-cyclopentene, 4-vinyl-1-methyl-1-cyclohexene, 4-vinyl-4-methyl-1-cyclohexene, 4-vinyl-1, 4-dimethyl-1-cyclohexene, 4-vinyl-1-cyclohexene and 4-allyl-1-cyclohexene, further preferably selected from at least one of 5-vinyl-2-norbornene (VNB), VNB, C, At least one of 5-allyl-2-norbornene, 6-methyl-5-allyl-2-norbornene, 5- (3-butenyl) -2-norbornene, 5- (3-butenyl-2-methyl) -2-norbornene, 5- (4-pentenyl) -2-norbornene, 5- (5-hexenyl) -2-norbornene, 5- (6-heptenyl) -2-norbornene and 5- (7-octenyl) -2-norbornene.

The second aspect of the invention provides a preparation method of long-chain branched ethylene-propylene rubber, which is carried out in the presence of a vanadium-based catalyst, wherein the vanadium-based catalyst comprises the following components:

and (2) component A: a main catalyst selected from the general formula VOCl₂OR¹And VOCl (OR)¹)(OR²) At least one of the vanadium-containing compounds shown in the specification, wherein R¹And R²Are the same or different and are each independently selected from C₁～C₁₀Alkyl of (C)₁～C₁₀Halogenoalkyl of, C₃～C₁₀Cycloalkyl of, C₃～C₁₀Halogenocycloalkyl or C₆～C₂₅Aryl of (a);

and (B) component: a cocatalyst which is an organoaluminum compound; and the number of the first and second groups,

optional component C: an activator having an oxidizing property to oxidize vanadium suboxides to vanadium higher oxides;

the preparation method comprises the following steps:

(1) mixing one of the component A and the component B with a monomer and a reaction medium, and then mixing with the other of the component A and the component B;

(2) optionally, adding component C into the system obtained in the step (1);

(3) carrying out polymerization reaction on the system to obtain the long-chain branched ethylene propylene rubber;

the monomer comprises ethylene, propylene and non-conjugated diene containing vinyl, and the amount of each monomer is such that the mass content of the ethylene structural unit in the long-chain branched ethylene-propylene rubber obtained by polymerization is 30.0-78.0 wt%, preferably 35.0-75.0 wt%, and most preferably 40.0-70.0 wt% based on the mass of the long-chain branched ethylene-propylene rubber; the mass content of the propylene structural unit is 10.0 wt% -55.0 wt%, preferably 15.0 wt% -50.0 wt%, and most preferably 18.0 wt% -45.0 wt%; the mass content of the vinyl group-containing nonconjugated diene structural unit is 10.1 to 40.0 wt%, preferably 10.1 to 35.0 wt%, and more preferably 10.1 to 30.0 wt%; the molar content of the vinyl group-containing nonconjugated diene structural unit is 2.1 to 14.0 mol%, preferably 2.3 to 12.0 mol%, and more preferably 2.5 to 10.0 mol%.

According to a preferred embodiment of the invention, R¹And R²Each independently selected from the group consisting of methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, 2-dichloro-1-ethyl, 1-dichloro-2-propyl, 1-dichloro-2-methyl-2-propyl, 3-dichloro-1-propyl, 2-dichloro-1-propyl, 1-dichloro-2-butyl, 3-dichloro-1-butyl, 2-dichloro-1-butyl, 1-dichloro-2-pentyl, 2-dichloro-1-pentyl, 1-dichloro-2-hexyl, 2-dichloro-1-hexyl, 2, 2-trichloro-1-ethyl group, 3,3, 3-trichloro-1-propyl group, 1,1, 1-trichloro-2-methyl-2-propyl group, 1,1, 1-trichloro-2-butyl group, 1,1, 1-trichloro-2-methyl-2-butyl group, p-methylphenyl group, 2-ethylphenyl group, 4-ethylphenyl group, 2-isopropylphenyl group, 2-tert-butylphenyl group, 2-sec-butylphenyl group, 2, 4-dimethylphenyl group, 2, 6-dimethylphenyl group, 2,3, 4-trimethylphenyl group, 2,3, 5-trimethylphenyl group, 2,3, 6-trimethylphenyl group, 2-trichloro-2-propyl group, 1,1, 1-trichloro-2-methyl-2-butyl, 2,4, 6-trimethylphenyl group, 2, 4-diethylphenyl group, 2, 6-diethylphenyl group, 2,4, 6-triethylphenyl group, 2, 3-di-t-butylphenyl group, 2, 4-di-t-butylphenyl group, 2, 5-di-t-butylphenyl group, 2, 6-di-t-butylphenyl group, 2,3, 4-tri-t-butylphenyl group, 2,3, 5-tri-t-butylphenyl group, 2,3, 6-tri-t-butylphenyl group, 2,4,at least one of 6-tri-tert-butylphenyl, 2, 6-di-tert-butyl-4-methylphenyl, 4-tert-pentylphenyl, 3-pentadecylphenyl and 4-tert-octylphenyl.

The cocatalyst used in the present invention may be various organoaluminum compound cocatalysts conventional in the art, preferably, the cocatalyst is selected from alkylaluminum, alkylaluminum halide or a mixture thereof.

In particular, the alkylaluminum and alkylaluminum halide are preferably of the formula R_mAlX_3-mWherein R is C₁～C₁₀Alkyl of (C)₃～C₁₀Cycloalkyl of, C₇～C₁₀Aralkyl or C₆～C₁₀Each R may be the same or different, X is halogen, preferably Cl or Br, more preferably Cl, and m is 1, 1.5, 2 or 3.

Specifically, the aluminum alkyl is preferably at least one selected from the group consisting of trimethylaluminum, triethylaluminum, tri-n-propylaluminum, triisopropylaluminum, tri-n-butylaluminum, triisobutylaluminum, tri-n-pentylaluminum, tri-n-hexylaluminum, and tricyclohexylaluminum.

Specifically, the alkylaluminum halide is preferably at least one selected from the group consisting of dimethylaluminum monochloride, diethylaluminum monochloride, di-n-butylaluminum monochloride, diisobutylaluminum monochloride, methylaluminum dichloroide, ethylaluminum dichloroide, n-butylaluminum dichloroide, isobutylaluminum dichloroide, methylaluminum sesquichloride, ethylaluminum sesquichloride, n-butylaluminum sesquichloride and isobutylaluminum sesquichloride.

In the invention, the activating agent can be optionally added, and preferably, the activating agent is selected from C containing 2-5 chlorine atoms₁～C₂₀And/or C containing 2 to 5 chlorine atoms₂～C₂₀An ester of (a).

In the catalyst used in the invention, the dosage of the component B is related to the impurity content in the system, the dosage of the main catalyst, the dosage of the monomer, the molecular weight of the polymerization product, the molecular weight distribution and other factors. Generally, the polymerization activity can be improved by increasing the amount of the cocatalyst in the polymerization system within a certain range, and the cocatalyst is too small, so that the number of generated active centers is small, the catalytic activity is low, and the monomer polymerization conversion rate is low. However, when the amount of the cocatalyst is too large, the main catalyst is excessively reduced to affect the monomer conversion, and chain transfer is caused to decrease the molecular weight of the polymer. In addition, too much cocatalyst can also lead to increased catalyst costs. Therefore, it is preferable that the molar ratio of the component B in terms of Al element to the component a in terms of V element in the catalyst used in the present invention is 5 to 35: 1, preferably 7-30: 1, more preferably 10 to 25: 1; the molar ratio of the component C to the component A calculated by the element V is 0-6: 1, preferably 0 to 5: 1, more preferably 0 to 4: 1.

in the preparation method of the present invention, the non-conjugated diene is defined as described above, and will not be described herein again.

According to the method of the invention, the monomer concentration is too high, so that the viscosity of the system is too high, and the production process is influenced. The excessively low monomer concentration leads to an increase in the amount of solvent used and an increase in cost. In the present invention, an appropriate monomer concentration is essential, and preferably, the total concentration of the monomers in the system is from 10g/L to 180g/L, preferably from 20g/L to 150g/L, and more preferably from 30g/L to 120 g/L.

According to the invention, the amount of catalyst used can be determined as desired, preferably the molar ratio of component A to monomer, calculated as element V, is 1.0X 10^-4～5.0×10^-3: 1, preferably 3.0X 10^-4～4.0×10^-3: 1, more preferably 5.0X 10^-4～3.0×10^-3：1。

In the present invention, the polymerization reaction may be an adiabatic polymerization reaction or a constant temperature polymerization reaction.

According to the invention, the polymerization temperature is generally from-60 ℃ to 55 ℃, preferably from-55 ℃ to 50 ℃ and more preferably from-50 ℃ to 45 ℃.

The monomer conversion and the polymer yield increase with the extension of the reaction time, but the reaction rate is faster at the beginning of the polymerization reaction for the vanadium-based catalyst, and as the reaction time is extended, part of the catalyst is deactivated and the reaction rate becomes slower. Therefore, the polymerization reaction time is generally selected from 1 minute to 2 hours, preferably from 2 minutes to 1.5 hours, and more preferably from 2.5 minutes to 1.2 hours.

The polymerization pressure is related to the polymerization temperature, the higher the pressure. In addition, increasing the pressure is favorable for the gas monomer to dissolve in the solution for polymerization, but too high a pressure will place high demands on the pressure resistance of the polymerization reactor. Therefore, the polymerization pressure is generally selected from 0.01MPa to 3MPa, preferably from 0.05MPa to 2MPa, and more preferably from 0.1MPa to 1 MPa.

The polymerization method of the present invention includes bulk polymerization, solution polymerization or slurry polymerization, and may be a batch process or a continuous process. The monomers can be fed in one portion or in batches or continuously.

When solution polymerization is employed, the solvent used may be selected from C₃～C₁₀Saturated alkane of (C)₃～C₁₀Cycloalkane of C₆～C₁₀At least one aromatic hydrocarbon of (2), preferably at least one selected from the group consisting of n-butane, n-pentane, cyclopentane, n-hexane, cyclohexane, methylcyclopentane, methylcyclohexane, n-heptane, n-octane, isooctane, n-nonane, n-decane, toluene and xylene. The choice of solvent is related to the polymerization process conditions, the polymer molecular weight and the molecular weight distribution. Generally, to prepare high molecular weight polymers, solvents are selected that are not susceptible to chain transfer; to prepare low molecular weight polymers, solvents are selected that are susceptible to chain transfer.

A third aspect of the invention provides a long chain branched ethylene-propylene rubber made by the above process. The long-chain branched ethylene-propylene rubber has various properties of the long-chain branched ethylene-propylene rubber, and is not described in detail herein.

The invention can greatly improve the insertion rate and the branching degree of the non-conjugated diene monomer containing vinyl, obtain the long-chain branched ethylene-propylene rubber with high side chain vinyl content, high branching degree, low gel content and even no gel, obviously improve the quality and the performance of products and reduce the production cost.

Additional features and advantages of the invention will be set forth in the detailed description which follows.

Detailed Description

Preferred embodiments of the present invention will be described in more detail below. While the following describes preferred embodiments of the present invention, it should be understood that the present invention may be embodied in various forms and should not be limited by the embodiments set forth herein.

The polymerization product was characterized by Fourier Infrared Spectroscopy (FTIR) and the ethylene and propylene contents of the long chain branched ethylene-propylene rubber were calculated according to ASTM-D3900-95.

The viscosity average molecular weight of the polymer was measured at 135 ℃ using trichlorobenzene as a solvent according to literature reported methods, see Macromolecules,1984,17, 2767.

And testing the gel content of the long-chain branched ethylene propylene rubber according to the petrochemical industry standard SH/T1050-.

Measuring the tan delta value of the long-chain branched ethylene-propylene rubber at different temperatures by a Dynamic Mechanical Analyzer (DMA), and subtracting the tan delta value at 100 ℃ from the tan delta value at 0 ℃ to obtain the tan delta. The larger the value of Δ tan δ, the lower the degree of long chain branching.

Double bond titration was performed according to GB/T5532-2008 and the content of non-conjugated diolefins in the polymer which also retained double bonds was determined. Part of the vinyl groups will participate in the branching reaction and cannot be detected by titration.

Example 1

100mL of hexane, 0.404g of VNB, 1.8g of ethylene and 8.2g of propylene were charged into the reactor, and 0.5mmol of the cocatalyst of aluminum sesquiethylate chloride (Et) was added thereto, respectively, at 23 ℃ with stirring₃Al₂Cl₃) And 0.02mmol of a procatalyst VOCl (OR)¹)(OR²) (wherein R is¹Is 1,1, 1-trichloro-2-methyl-2-propyl, R²4-tert-octylphenyl) were copolymerized. The temperature rose to 33 ℃ during the polymerization. After the polymerization reaction is carried out for 30min, 2mL of ethanol is added to stop the reaction, and then the reaction solution is added into 5% hydrochloric acid ethanol solution by mass fraction, so that a polymerization product is precipitated. The polymerization product was vacuum-dried at 40 ℃ to constant weight to obtain 1.5g of an ethylene-propylene-VNB terpolymer having a viscosity average molecular weight of 3.4X 10⁵g·mol^-1. The gel content of the copolymer was 0, the ethylene content was 59.7 wt%, the propylene content was 29.2 wt%, the VNB content was 11.1 wt% (3.1 mol%), and Δ tan. delta. was 0.08, which is significantly lower than that of linear ethylene-propylene copolymer in comparative example 1The delta tan delta value for the olefinic bipolymer (0.92) indicates a high degree of long chain branching.

The catalyst component of the present invention is extremely important for the synthesis of long chain branched ethylene-propylene rubber which is substantially free of gel. And using conventional VOCl₃/Et₃Al₂Cl₃Compared with the catalyst (comparative example 2) which catalyzes the copolymerization of ethylene/propylene/VNB to generate a large amount of gel (19.7%), the system and the method which are described in the example 1 can be used for preparing a long-chain branched ethylene propylene diene rubber product with high side chain vinyl content, high branching degree and no gel.

Example 2

The polymerization process was as described in example 1, except that: the polymerization was started at 5 ℃ and the mass of the VNB monomer added was 0.673g, that of the ethylene monomer 0.9g and that of the propylene monomer 4.1 g. 0.75g of an ethylene-propylene-VNB terpolymer having a viscosity average molecular weight of 1.8X 10 was obtained⁵g·mol^-1. The copolymer had a gel content of 0, an ethylene content of 47.4 wt%, a propylene content of 26.8 wt%, a VNB content of 25.8 wt% (8.5 mol%), and a Δ tan δ of 0.04.

The terpolymer of example 2 has a high degree of long chain branching compared to comparative example 1; compared with the comparative example 2, the system and the method of the example 2 can be used for preparing the long-chain branched ethylene propylene diene monomer rubber product with high side chain vinyl content, high branching degree and no gel.

Example 3

The polymerization process was as described in example 2, except that: VNB was added in an amount of 0.332g and VOCl (OR) was used as the main catalyst¹)(OR²) (wherein R is¹And R²Are all 2,2, 2-trichloro-1-ethyl). 0.96g of an ethylene-propylene-VNB terpolymer having a viscosity average molecular weight of 1.6X 10 was obtained⁵g·mol^-1. The copolymer had a gel content of 0.5%, an ethylene content of 53.5% by weight, a propylene content of 36.4% by weight, a VNB content of 10.1% by weight (2.9 mol%) and a tan. delta.of 0.06.

The terpolymer of example 3 has a high degree of long chain branching compared to comparative example 1; compared with the comparative example 3 (gel content is 36.0%), by adopting the system and the method described in the example 3, the long-chain branched ethylene propylene diene monomer rubber product with high side chain vinyl content, high branching degree and low gel content can be prepared.

Example 4

The polymerization process was as described in example 2, except that: the main catalyst is VOCl₂(OR¹) (wherein R is¹2,2, 2-trichloro-1-ethyl), and an activator (component C)1,1, 1-trichloroethane is added, the molar ratio of the activator to the main catalyst being 3: 1. 1.13g of an ethylene-propylene-VNB terpolymer having a viscosity-average molecular weight of 2.0X 10 was obtained⁵g·mol^-1. The copolymer had a gel content of 0.1%, an ethylene content of 51.8 wt%, a propylene content of 37.1 wt%, a VNB content of 11.1 wt% (3.3 mol%), and a Δ tan. delta.of 0.10.

The terpolymer of example 4 has a high degree of long chain branching compared to comparative example 1; compared with the comparative example 3 (gel content is 36.0%), by adopting the system and the method described in the example 4, the long-chain branched ethylene propylene diene monomer rubber product with high side chain vinyl content, high branching degree and low gel content can be prepared.

Example 5

The polymerization process was as described in example 1, except that: the main catalyst is VOCl (OR)¹)(OR²) (wherein R is¹Is 1,1, 1-trichloro-2-methyl-2-propyl, R²2, 6-di-tert-butyl-4-methylphenyl) and an Al/V molar ratio of 15. 1.19g of an ethylene-propylene-VNB terpolymer having a viscosity average molecular weight of 3.7X 10 was obtained as a polymer product⁵g·mol^-1. The copolymer had a gel content of 0, an ethylene content of 60.7 wt%, a propylene content of 28.6 wt%, a VNB content of 10.7 wt% (3.0 mol%), and a Δ tan δ of 0.08.

The terpolymer of example 5 has a high degree of long chain branching compared to comparative example 1; compared with the comparative example 2 (gel content is 19.7%), the system and the method of the example 5 can be used for preparing the long-chain branched ethylene propylene diene monomer rubber product with high side chain vinyl content, high branching degree and no gel.

Comparative example 1

The polymerization procedure was as in example 1, except that: in comparative example 1 no VNB was added. Thus, the product obtained in comparative example 1 was 2.4g of a linear ethylene-propylene binary copolymer. The copolymer had a gel content of 0, an ethylene content of 47.9 wt%, an ethylene content of 52.1 wt% and a Δ tan δ of 0.92.

Comparative example 2

The polymerization process was as described in example 1, except that: by using VOCl₃As the main catalyst. 0.355g of a polymer product having a gel content of 19.7% was obtained. Due to the large amount of gel in the terpolymer, the ethylene monomer conversion, propylene monomer conversion, VNB monomer conversion and copolymer composition could not be determined.

Comparative example 3

The polymerization procedure was as in example 1, except that: by using VOCl₃As the main catalyst, VNB was 0.337g in mass. 1.1g of a polymer product having a gel content of 36.0% was obtained. Due to the large amount of gel in the terpolymer, the ethylene monomer conversion, propylene monomer conversion, VNB monomer conversion and copolymer composition could not be determined.

Having described embodiments of the present invention, the foregoing description is intended to be exemplary, not exhaustive, and not limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments.