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CN-121203058-B - Polyolefin polymerization morphology regulator, supported metallocene polyolefin catalyst and preparation method thereof

CN121203058BCN 121203058 BCN121203058 BCN 121203058BCN-121203058-B

Abstract

The invention discloses a polyolefin polymerization morphology regulator, a supported metallocene polyolefin catalyst and a preparation method thereof. The structural formula of the polymerization morphology regulator is The connector is connected with A 1 ~A n groups, and the A 1 ~A n groups all have at least one hydroxyl group, and n=2-6. The supported metallocene polyolefin catalyst comprises a carrier, a metallocene polyolefin catalyst supported on the carrier and the polyolefin polymerization morphology regulator. The polyolefin polymerization morphology modifier is a polyhydroxy compound, is an organic matter, is used for controllably adjusting the morphology of a product in polyolefin synthesis, does not introduce new ash and metal components, and is realized without additional equipment and only needs to be carried out in conventional equipment by using conventional reagents. Meanwhile, the polyolefin polymerization morphology modifier is added into the catalyst, so that the activity of the catalyst is more gentle and fully released, and the activity of the catalyst can be improved.

Inventors

  • FU HONGYUAN
  • WU LIPING
  • QIN JUN
  • Qiao Liangjie
  • LI XINLE
  • LIU HENGZHI
  • KANG KAI

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
20260512
Application Date
20251128

Claims (11)

  1. 1. The supported metallocene polyolefin catalyst comprises a carrier, and a metallocene polyolefin catalyst, a polyolefin polymerization morphology regulator and a cocatalyst MAO which are supported on the carrier; the supported metallocene polyolefin catalyst is prepared by the following steps: Carrying out a first reaction between the carrier and MAO in a solvent, and then adding the polyolefin polymerization morphology modifier to carry out a second reaction; After the reaction is finished, adding the metallocene polyolefin catalyst to perform a third reaction to obtain the supported metallocene polyolefin catalyst; The structural formula of the polyolefin polymerization morphology regulator is any one of formula IV-1-formula IV-3, formula IV-6-formula IV-10, formula IV-12-formula IV-15, formula IV-17, formula IV-19, formula IV-20-formula IV-24, formula IV-26, formula IV-27, formula IV-30, formula IV-32, formula IV-39, formula IV-42, formula IV-44, formula IV-46, formula IV-47 and formula IV-52. 。
  2. 2. The supported metallocene polyolefin catalyst according to claim 1, wherein the support is selected from at least one of silica gel, magnesium dichloride, graphene oxide, MXene, polymeric alumina, hydrotalcite.
  3. 3. The supported metallocene polyolefin catalyst according to claim 1, wherein the metallocene polyolefin catalyst is selected from at least one of bis (1-methyl-3-butylcyclopentadienyl) zirconium dichloride, dicyclopentadienyl zirconium dichloride, rac-ethylenebis (indenyl) zirconium dichloride, rac-ethylenebis (tetrahydroindenyl) zirconium dichloride, isopropylidene (cyclopentadienyl) (fluorenyl) zirconium dichloride, dicyclopentadienyl titanium dichloride, dicyclopentadienyl hafnium dichloride, ethylenebis (indenyl) hafnium dichloride, dimethylsilyl bis (2-methylindenyl) zirconium dichloride, dimethylsilyl bis (2-methyl-4-phenylindenyl) zirconium dichloride, dimethylsilyl (cyclopentadienyl) (t-butylamino) titanium dichloride.
  4. 4. The supported metallocene polyolefin catalyst of claim 1, wherein the metallocene polyolefin catalyst comprises 0.1-1.0% of the catalyst mass, and the polyolefin polymerization morphology modifier comprises 1-10% of the catalyst mass.
  5. 5. The supported metallocene polyolefin catalyst of claim 1, wherein the MAO comprises 5% -30% of the catalyst mass.
  6. 6. A process for preparing a supported metallocene polyolefin catalyst according to any of claims 1 to 5, wherein the process comprises the steps of: Carrying out a first reaction between the carrier and MAO in a solvent, and then adding the polyolefin polymerization morphology modifier to carry out a second reaction; And after the reaction is finished, adding the metallocene polyolefin catalyst to perform a third reaction to obtain the supported metallocene polyolefin catalyst.
  7. 7. The process according to claim 6, wherein the solvent is toluene.
  8. 8. The preparation method of claim 6, wherein the metallocene polyolefin catalyst is used in an amount of 10-150 mu mol/g carrier.
  9. 9. The method according to claim 6, wherein the molar ratio of MAO to the metallocene polyolefin catalyst is (10-5000): 1.
  10. 10. The method according to claim 6, wherein the molar ratio of aluminum in MAO to hydroxyl groups in the polyolefin polymerization morphology modifier is (5-100): 1.
  11. 11. The method according to claim 6, wherein the first reaction and the second reaction are carried out at a temperature of 40 to 120 ℃ for 1 to 10 hours, and the third reaction is carried out at a temperature of room temperature for 1 to 8 hours.

Description

Polyolefin polymerization morphology regulator, supported metallocene polyolefin catalyst and preparation method thereof Technical Field The invention relates to the field of polyolefin, in particular to a polyolefin polymerization morphology regulator, a supported metallocene polyolefin catalyst and a preparation method thereof. Background Metallocene catalysts, which are the fifth generation catalysts for polyolefin synthesis, are characterized by single sites, which enable precise control of the polymerization process. The metallocene catalyst can realize the precise regulation and control of the molecular weight distribution, the stereoregularity of a molecular chain, the insertion rate of a comonomer and the sequence distribution of the polymer, and realize the design of the polymer molecule. In actual production, bulk density of the product is a critical parameter, referring to the mass of the polyolefin product deposited per unit volume. When the product shape is irregular, caking adhesion occurs, so that the bulk density is reduced, the space utilization rate is reduced, even the situation of blocking a production device and a transportation pipeline can occur, and the production and transportation are greatly influenced. Researchers remain closely concerned with increasing the bulk density of the product, and wish to increase the bulk density of the product as much as possible by the catalyst preparation process. In the aspect of carrier preparation engineering, CN101423575A develops an alkyl aluminoxane/magnesium chloride/silica gel triple carrier, and the pore structure is improved by magnesium chloride, so that the polyethylene bulk density is obviously higher than that of a single silica gel carrier system, and the catalyst activity is improved by more than 1 time. CN115073629B adopts divinylbenzene-sulfoacid styrene copolymer/TiO 2 composite carrier, and the morphology of the particles is regulated and controlled by an organic phase, and the inorganic phase provides rigid support. In the aspect of the loading process, CN201080058019.1 proposes a staged temperature fixing method, wherein part of the cocatalyst is pre-fixed on the carrier at the high temperature in the first stage, and the rest of the cocatalyst and the metallocene compound are fixed at the low temperature in the second stage. The method ensures that the active component uniformly penetrates into the pores of the carrier, avoids surface enrichment and produces high bulk density polyolefin. WO2018101794A2 adds a sulfate/phosphate and white mineral oil composite stabilizer into a catalyst system, reduces particle agglomeration in the polymerization process, maintains continuous operation of a reactor, and indirectly improves the bulk density of a polymer. The method effectively improves the stacking density of the products, but has obvious defects. The carrier preparation engineering needs additional equipment and technology, new ash is introduced, or the production technology is complex, the sectional temperature fixing method increases the production energy consumption, has higher requirements on the production equipment, and the method of adding the sulfate/phosphate and other composite stabilizers sacrifices the activity of a part of catalysts, and simultaneously introduces new metal components. Disclosure of Invention The invention aims to provide a polyolefin polymerization morphology regulator, a supported metallocene polyolefin catalyst and a preparation method thereof, wherein polyhydroxy compounds are used as the polymerization morphology regulator for polyolefin preparation, new ash and metal components are not introduced, and meanwhile, the polyhydroxy compounds are added into the catalyst, so that the activity of the catalyst is milder and more fully released, and the activity of the catalyst can be improved. In order to achieve the above purpose, the present invention adopts the following technical scheme: The invention provides a polyolefin polymerization morphology modifier, wherein the polymerization morphology modifier is a polyhydroxy compound, the structural formula is shown in the specification I, a connector is connected with an A 1~An group, the A 1~An groups all have at least one hydroxyl group, and n=2-6; I is a kind of The connector is selected from any one of the formulas II-1 to II-9, and the dotted line represents the connection position of the connector and the A 1~An group; In the formula II-1 to formula II-9, R 1~R4 is independently selected from H, halogen, C1-C10 alkyl, C1-C10 alkoxy, C1-C10 alkylthio, C1-C10 silane, and alkyl or alkoxy, alkylthio, silane substituted aryl; The A 1~An is independently selected from any one of the formulas III-1 to III-6, and the dotted line represents the connection position of the A 1~An group and the connector; in the formulas III-1 to III-6, R is independently selected from H, halogen, C1-C10 alkyl, C1-C10 alkoxy, C1-C10 alkylthio and C1-C10 silane. According to