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CN-121991307-A - Polyolefin elastomer copolymerized with aromatic vinyl and conjugated diene and preparation method thereof

CN121991307ACN 121991307 ACN121991307 ACN 121991307ACN-121991307-A

Abstract

The invention relates to a polyolefin elastomer copolymerized by aromatic vinyl and conjugated diene and a preparation method thereof, wherein the copolymer is obtained by anionic polymerization of raw materials of the aromatic vinyl and the conjugated diene, and then hydrogenation is carried out on the copolymer by using a catalyst, so that the polyolefin elastomer is obtained. Compared with the prior art, the invention has narrower molecular weight distribution and higher structural adjustability.

Inventors

  • LIN FENG
  • XIE TINGTING
  • GONG GUANGBI
  • ZHENG HONGBING
  • HAN YAN
  • FENG YUZHI
  • WEN JINGBIN
  • CHEN FEI
  • WANG YUCHAO

Assignees

  • 中石油(上海)新材料研究院有限公司
  • 中国石油天然气股份有限公司

Dates

Publication Date
20260508
Application Date
20241104

Claims (10)

  1. 1. A polyolefin elastomer copolymerized with an aromatic vinyl and a conjugated diene, characterized in that a copolymer is obtained by anionic polymerization using a raw material of the aromatic vinyl and the conjugated diene, and then the copolymer is hydrogenated using a catalyst, thereby obtaining a polyolefin elastomer; 50-150 parts of aromatic vinyl and a structure regulator are added in one step, two parts of an initiator are added in two steps, 100-300 parts of conjugated diene is added in three steps, 50-150 parts of aromatic vinyl is added in four steps in the anionic polymerization process, and the volume/mass ratio of the structure regulator to the initiator to the conjugated diene is (0.5-2 mL): (2-8 mL): (100-300 g).
  2. 2. The polyolefin elastomer copolymerized with an aromatic vinyl and a conjugated diene according to claim 1, wherein the aromatic vinyl is selected from one or more of styrene, vinyl toluene, α -methylstyrene, 4-t-butylstyrene, 4-methylstyrene, 3, 5-diethylstyrene, 3, 5-di-n-butylstyrene, 4-n-propylstyrene and 4-dodecylstyrene.
  3. 3. The polyolefin elastomer copolymerized with an aromatic vinyl and a conjugated diene according to claim 1, wherein the structure-adjusting agent is selected from one or more of tetrahydrofuran, ethyltetrahydrofurfuryl ether, tetramethyldivinyl diamine, tetrahydrofuranmethanol, diethylene glycol dimethyl ether.
  4. 4. The polyolefin elastomer copolymerized with an aromatic vinyl and a conjugated diene according to claim 1, wherein the initiator is selected from one or more of n-butyllithium, sec-butyllithium, tert-butyllithium, n-hexyllithium.
  5. 5. The polyolefin elastomer according to claim 1, wherein the conjugated diene is selected from one or more of 1, 3-butadiene and isoprene.
  6. 6. A process for producing the polyolefin elastomer copolymerized with an aromatic vinyl and a conjugated diene as claimed in any one of claims 1 to 5, characterized in that it comprises the steps of: S1, adding a solvent, aromatic vinyl and a structure regulator, adding an initiator to initiate polymerization, then adding conjugated diene to perform anionic polymerization, and then adding aromatic vinyl to perform anionic polymerization to obtain a basic glue solution; s2, diluting the basic glue solution to prepare hydrogenated glue solution, then adding a catalyst, introducing hydrogen for pressurizing, and heating for reaction to obtain the polyolefin elastomer copolymerized by the aromatic vinyl and the conjugated diene.
  7. 7. The process for producing a polyolefin elastomer copolymerized with an aromatic vinyl and a conjugated diene according to claim 6, wherein the solvent in the step S1 is one or more selected from pentane, hexane, heptane, octane, cyclopentane and cyclohexane, and the mass ratio of the solvent to the conjugated diene is (2500-3500): (100-300).
  8. 8. The process for producing a polyolefin elastomer copolymerized with an aromatic vinyl and a conjugated diene according to claim 6, wherein the polymerization reaction is initiated at a temperature of 30 to 80℃and the anionic polymerization reaction is initiated for 20 to 60 minutes, the anionic polymerization reaction of the conjugated diene is initiated for 30 to 90 minutes, and the anionic polymerization reaction of the aromatic vinyl is initiated for 20 to 60 minutes in step S1.
  9. 9. The process for producing a polyolefin elastomer copolymerized with an aromatic vinyl and a conjugated diene according to claim 6, wherein the concentration of the hydrogenated gum solution in step S2 is 1 to 20% by weight.
  10. 10. The process for producing a polyolefin elastomer copolymerized with an aromatic vinyl and a conjugated diene according to claim 6, wherein the catalyst in step S2 is a nickel-based catalyst, the mass ratio of the catalyst to the base dope is (0.05-1): 1, The pressurizing pressure is 1-15MPa, The reaction temperature is 80-250 ℃ and the reaction time is 1-12h.

Description

Polyolefin elastomer copolymerized with aromatic vinyl and conjugated diene and preparation method thereof Technical Field The invention belongs to the technical field of polymer preparation, and relates to a polyolefin elastomer copolymerized by aromatic vinyl and conjugated diene and a preparation method thereof. Background Ethylene and higher alpha-olefin copolymers are a new class of materials of great interest that possess both plastic and rubber dual properties due to their unique structure. A part of this material is a polyethylene structure, but its chain crystalline region is weakened by the introduction of higher alpha-olefins, thereby degrading its plastic properties. At the same time, the crystalline segments of polyethylene act as physical cross-links in the material, so that the final product exhibits the characteristics of a thermoplastic elastomer. Olefin Elastomers (POE) are the most representative products of copolymers of ethylene with higher alpha-olefins. It is prepared by using ethylene as raw material and high-carbon alpha-olefin (such as 1-butene, 1-hexene or 1-octene) as comonomer, and polymerizing under the action of homogeneous metal catalyst. The POE has no unsaturated double bond in the molecular structure, has narrow molecular weight distribution and uniform short-chain branch structure, thus having excellent physical and mechanical properties such as high elasticity, high strength, high elongation and the like, and simultaneously showing good tolerance under low temperature conditions. In recent years, with the progress of technology, olefin Block Copolymers (OBC) have been developed successively. The OBC has obviously improved performance compared with the traditional POE due to the unique molecular structure, raw material proportion and improvement of the process technology. In particular in polypropylene (PP) systems, OBC exhibits excellent low temperature toughness and only small additions are required to achieve a toughening effect comparable to conventional POE, reducing negative impact on stiffness. In addition, the heat resistant temperature of the OBC is also increased, which makes the range of use temperatures wider. In terms of processability, the high Melt Index (MI) of the OBC can be achieved by some products even reaching 100, the flowability of the material is obviously improved, and the production efficiency is improved. At present, polyolefin elastomer is produced by directly copolymerizing ethylene and higher alpha-olefin under the action of a metallocene catalyst. Difficulties in polyolefin elastomer production have focused mainly on the three aspects of catalyst, alpha-olefin, and polymerization process, with catalyst design and development being the greatest challenges in the production process. Existing commercial products rely primarily on bridged metallocene catalysts and Constrained Geometry (CGC) catalysts. The research and development process of the metallocene catalyst can be traced back to 1988, and Exxon mobil discloses an industrial production method for copolymerizing ethylene and 1-octene for the first time, and in 1993, the Dow chemical registered trademark Insite of the CGC catalyst, and POE products with narrow molecular weight distribution are introduced by utilizing the technology. In addition, the choice and use of higher alpha-olefins affects the chain structure and properties of the polymer, which has a significant impact on the properties of polyolefin elastomers, while higher alpha-olefins are produced in low yields and at high costs, and thus a balance between improving material properties and cost control is needed. Finally, the polymerization process is less difficult than the other two, but still requires precise control of various parameters such as temperature, pressure and reaction time to ensure product quality. The stability and controllability of the polymerization process have been significantly improved due to advances in technology at different times. Patent CN105273010A discloses a limited configuration dinuclear metallocene compound, a preparation method and application thereof, and the double-center CGC of the metallocene compound not only has the activity of a single-center catalyst, but also can conveniently control the electronic environment and the space environment of two metal centers by adjusting the length of a carbon bridge, thereby regulating and controlling the molecular weight distribution of a polymer and producing wide-distribution polyolefin. However, the patent uses a conventional metallocene catalyst process to produce polyolefin elastomers with a broad molecular weight distribution. Patent CN116751326a discloses a catalyst for synthesizing polyolefin elastomer, polyolefin elastomer and preparation method, using metallocene catalyst (phenyl, indenyl) -methylene bridged (indenyl, fluorenyl) zirconium dichloride as main catalyst, triisobutylaluminum as cocatalyst, adopting continuous polymerization proce