1
|
Zhu B, Liu K, Luo L, Zhang Z, Xiao Y, Sun M, Jie S, Wang WJ, Hu J, Shi S, Wang Q, Li BG, Liu P. Covalent Organic Framework-Supported Metallocene for Ethylene Polymerization. Chemistry 2023; 29:e202300913. [PMID: 37341127 DOI: 10.1002/chem.202300913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 06/21/2023] [Accepted: 06/21/2023] [Indexed: 06/22/2023]
Abstract
The loading of homogeneous catalysts with support can dramatically improve their performance in olefin polymerization. However, the challenge lies in the development of supported catalysts with well-defined pore structures and good compatibility to achieve high catalytic activity and product performance. Herein, we report the use of an emergent class of porous material-covalent organic framework material (COF) as a carrier to support metallocene catalyst-Cp2 ZrCl2 for ethylene polymerization. The COF-supported catalyst demonstrates a higher catalytic activity of 31.1×106 g mol-1 h-1 at 140 °C, compared with 11.2×106 g mol-1 h-1 for the homogenous one. The resulting polyethylene (PE) products possess higher weight-average molecular weight (Mw ) and narrower molecular weight distribution (Ð) after COF supporting, that is, Mw increases from 160 to 308 kDa and Ð drops from 3.3 to 2.2. The melting point (Tm ) is also increased by up to 5.2 °C. Moreover, the PE product possesses a characteristic filamentous microstructure and demonstrates an increased tensile strength from 19.0 to 30.7 MPa and elongation at break from 350 to 1400 % after catalyst loading. We believe that the use of COF carriers will facilitate the future development of supported catalysts for highly efficient olefin polymerization and high-performance polyolefins.
Collapse
Affiliation(s)
- Bangban Zhu
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering Zhejiang University, Hangzhou, 310027, P. R. China
| | - Kan Liu
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering Zhejiang University, Hangzhou, 310027, P. R. China
| | - Liqiong Luo
- National-Certified Enterprise Technology Center, Kingfa Science and Technology Co., Ltd., Guangzhou, 510663, P. R. China
| | - Ziyang Zhang
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering Zhejiang University, Hangzhou, 310027, P. R. China
- Institute of Zhejiang University - Quzhou, 99 Zheda Rd, Quzhou, 324000, P. R. China
| | - Yangke Xiao
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering Zhejiang University, Hangzhou, 310027, P. R. China
| | - Minghao Sun
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering Zhejiang University, Hangzhou, 310027, P. R. China
| | - Suyun Jie
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering Zhejiang University, Hangzhou, 310027, P. R. China
| | - Wen-Jun Wang
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering Zhejiang University, Hangzhou, 310027, P. R. China
- Institute of Zhejiang University - Quzhou, 99 Zheda Rd, Quzhou, 324000, P. R. China
| | - Jijiang Hu
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering Zhejiang University, Hangzhou, 310027, P. R. China
| | - Shengbin Shi
- Institute of Zhejiang University - Quzhou, 99 Zheda Rd, Quzhou, 324000, P. R. China
| | - Qingyue Wang
- Institute of Zhejiang University - Quzhou, 99 Zheda Rd, Quzhou, 324000, P. R. China
| | - Bo-Geng Li
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering Zhejiang University, Hangzhou, 310027, P. R. China
| | - Pingwei Liu
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological Engineering Zhejiang University, Hangzhou, 310027, P. R. China
- Institute of Zhejiang University - Quzhou, 99 Zheda Rd, Quzhou, 324000, P. R. China
| |
Collapse
|
2
|
Wen B, Hu H, Kang D, Sang C, Mao G, Xin S. High-Efficiency Mono-Cyclopentadienyl Titanium and Rare-Earth Metal Catalysts for the Production of Syndiotactic Polystyrene. Molecules 2023; 28:6792. [PMID: 37836635 PMCID: PMC10574108 DOI: 10.3390/molecules28196792] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Revised: 07/24/2023] [Accepted: 07/31/2023] [Indexed: 10/15/2023] Open
Abstract
Syndiotactic polystyrene (SPS) refers to a type of thermoplastic material with phenyl substituents that are alternately chirally attached on both sides of an aliphatic macromolecular main chain. Owing to its excellent physical and mechanical properties, as well as its chemical stability, high transparency, and electrical insulation characteristics, SPS is used in a wide variety of technical fields. SPS is commonly produced via the stereoselective transition metal-catalyzed coordination polymerization method mediated by stereospecific catalysts, which consists of anionic mono-cyclopentadienyl derivative η5-coordinated single active metal centers (referred to as "mono-Cp'-M"), with active center metals involving Group 4 transition metals (with an emphasis on titanium) and rare-earth (RE) metals of the periodic table. In this context, the use of mono-cyclopentadienyl titanocene (mono-Cp'Ti) catalysts and mono-cyclopentadienyl rare-earth metal (mono-Cp'RE) metallocene catalysts for the syndiospecific polymerization of styrene is discussed. The effects of the mono-cyclopentadienyl ligand structure, cationic active metal types, and cocatalysts on the activity and syndiospecificity of mono-Cp' metallocene catalysts are briefly surveyed.
Collapse
Affiliation(s)
- Bo Wen
- Provincial Key Laboratory of Polyolefin New Materials, College of Chemistry & Chemical Engineering, The Northeast Petroleum University, Daqing 163318, China
| | - Hongfan Hu
- PetroChina Petrochemical Research Institute, PetroChina Company Limited, Beijing 102206, China
| | - Di Kang
- Provincial Key Laboratory of Polyolefin New Materials, College of Chemistry & Chemical Engineering, The Northeast Petroleum University, Daqing 163318, China
| | - Chenggong Sang
- Provincial Key Laboratory of Polyolefin New Materials, College of Chemistry & Chemical Engineering, The Northeast Petroleum University, Daqing 163318, China
| | - Guoliang Mao
- Provincial Key Laboratory of Polyolefin New Materials, College of Chemistry & Chemical Engineering, The Northeast Petroleum University, Daqing 163318, China
| | - Shixuan Xin
- Provincial Key Laboratory of Polyolefin New Materials, College of Chemistry & Chemical Engineering, The Northeast Petroleum University, Daqing 163318, China
- PetroChina Petrochemical Research Institute, PetroChina Company Limited, Beijing 102206, China
| |
Collapse
|
3
|
Porous Organic Polymers-Supported Zeigler-Natta Catalysts for Preparing Highly Isotactic Polypropylene with Broad Molecular Weight Distribution. Polymers (Basel) 2023; 15:polym15030555. [PMID: 36771856 PMCID: PMC9919294 DOI: 10.3390/polym15030555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 01/11/2023] [Accepted: 01/12/2023] [Indexed: 01/24/2023] Open
Abstract
Porous organic polymers (POPs) have attracted much attention in numerous areas, including catalysis, adsorption and separation. Herein, POP supported Ziegler-Natta catalysts were designed for preparation of isotactic polypropylene (iPP). The POPs-based Ziegler-Natta catalysts exhibited the characteristic of broad molecular weight distribution (MWD > 11) with or without adding an extra internal electron donor. The added internal electron donor 3-methyl-5-tert-butyl-1,2-phenylene dibenzoate (ID-2) used in cat-2 showed good propylene polymerization activity of 15.3 × 106 g·PP/mol·Ti·h, high stereoregularity with 98.2% of isotacticity index and broad molecular weight distribution (MWD) of 12.3. Compared to the MgCl2-supported Ziegler-Natta catalysts (cat-4) with the same ID-2, cat-2 showed higher chain stereoregularity for propylene polymerization. As seen in the TREF results, the elution peak of PP-2 (124.0 °C, 91.7%) is 1.5 °C higher than the isotactic fraction from PP-4 (122.5 °C, 87.2%), and even 1.2 °C higher than PP-5 prepared from ID-3 with the characteristics of high stereoregularity. Moreover, the pentad methyl sequence mmmm of PP-2 (93.0%) from cat-2 is 0.5% higher than that of PP-4 from cat-4. XPS analysis revealed that the minute difference in binding energy of Ti, Mg, C and O atoms exist between the inorganic MgCl2 and the organic polymer based Z-N catalysts. The plausible interaction mechanism of active sites of Mg and Ti with the functional groups in the POP support and the added ID was proposed, which could be explained by their high stereoregularity and the broad molecular weight distribution of the POP-based Z-N catalysts.
Collapse
|
4
|
Syntheses of Silylene-Bridged Thiophene-Fused Cyclopentadienyl ansa-Metallocene Complexes for Preparing High-Performance Supported Catalyst. Catalysts 2022. [DOI: 10.3390/catal12030283] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
We synthesized a series of Me2Si-bridged ansa-zirconocene complexes coordinated by thiophene-fused cyclopentadienyl and fluorenyl ligands (Me2Si(2-R1-3-R2-4,5-Me2C7S)(2,7-R32C13H6))ZrMe2 (R1 = Me or H, R2 = H or Me, R3 = H, tBu, or Cl) for the subsequent preparation of supported catalysts. We determined that the fluorenyl ligand adopts an η3-binding mode in 9 (R1 = Me, R2 = H, R3 = H) by X-ray crystallography. Further, we synthesized a derivative 15 by substituting the fluorenyl ligand in 9 with a 2-methyl-4-(4-tert-butylphenyl)indenyl ligand, derivatives 20 and 23 by substituting the Me2Si bridge in 12 (R1 = Me, R2 = H, R3 = tBu) and 15 with a tBuO(CH2)6(Me)Si bridge, and the dinuclear congener 26 by connecting two complexes with a –(Me)Si(CH2)6Si(Me)– spacer. The silica-supported catalysts prepared using 12, 20, and 26 demonstrated up to two times higher productivity in ethylene/1-hexene copolymerization than that prepared with conventional (THI)ZrCl2 (21–26 vs. 12 kg-PE/g-(supported catalyst)), producing polymers with comparable molecular weight (Mw, 330–370 vs. 300 kDa), at a higher 1-hexene content (1.3 vs. 1.0 mol%) but a lower bulk density of polymer particles (0.35 vs. 0.42 g/mL).
Collapse
|
5
|
Abstract
Porous organic polymers (POPs) are widely used in various areas such as adsorption, separation and catalysis. In the present work, ionic liquid-modified porous organic polymers (IL-POPs) synthesized by dispersion polymerization were applied to immobilize metallocene catalysts for olefin polymerization. The prepared IL-POPs were characterized by Fourier transform infrared spectrometer (FT-IR), nitrogen sorption porosimetry, X-ray photoelectron spectroscopy (XPS), thermal gravimetric analysis (TGA), inductively coupled plasma atomic emission spectrometer (ICP) and scanning electron microscope (SEM) analysis. The IL-POPs obtained pores with surface specific area (SSA) ranging from 16.9 m2/g to 561.8 m2/g, and total pore volume (TPV) ranging from 0.08 cm3/g to 0.71 cm3/g. The supported catalysts Zr/MAO@IL-POPs exhibit great activity (3700 kg PE/mol·Zr·bar·h) in ethylene polymerization, and the GPC-IR results show that the polyethylene has narrow molecular weight distribution (2.2 to 2.8). The DSC results show that the melting point of prepared polyethylene was as high as 138 °C, and the TREF analysis results indicate that they have similar chemical composition distribution with elution temperature at 100.5–100.7 °C.
Collapse
|
6
|
Zhen Q, Zhang H, Sun H, Zhang Y. Tailoring the softness performance of polyethylene/polypropylene micro‐nanofibrous fabrics for skin contacts. J Appl Polym Sci 2022. [DOI: 10.1002/app.51530] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Qi Zhen
- School of Clothing Zhongyuan University of Technology Zhengzhou China
- School of Textiles Zhongyuan University of Technology Zhengzhou China
- Institute of Advanced Medical Polymers Henan Key Laboratory Medical Polymer Materials Technology and Application Xinxiang China
| | - Heng Zhang
- School of Textiles Zhongyuan University of Technology Zhengzhou China
- Institute of Advanced Medical Polymers Henan Key Laboratory Medical Polymer Materials Technology and Application Xinxiang China
| | - Huan‐Wei Sun
- School of Textiles Zhongyuan University of Technology Zhengzhou China
- Institute of Advanced Medical Polymers Henan Key Laboratory Medical Polymer Materials Technology and Application Xinxiang China
| | - Yi‐Feng Zhang
- School of Textiles Zhongyuan University of Technology Zhengzhou China
- Institute of Advanced Medical Polymers Henan Key Laboratory Medical Polymer Materials Technology and Application Xinxiang China
| |
Collapse
|