负载型茂金属催化剂用于制备宽相对分子质量分布聚乙烯的研究

摘要茂金属聚乙烯性能优越,但它的相对分子质量分布通常较窄会造成后续成型加工困难等一系列问题,限制其大规模应用。以甲基铝氧烷(MAO)改性硅胶为载体,茂金属化合物为活性组分得到负载型茂金属催化剂,并在淤浆体系中催化乙烯聚合得到茂金属聚乙烯。系统探究了制备条件对负载量的影响、聚合条件对活性的影响,同时利用扫描电子显微镜、电感耦合等离子质谱仪、激光粒度仪、高温凝胶渗透色谱仪等对催化剂和聚合产物分析表征。实验结果表明,负载型催化剂活性释放平缓,将其用于乙烯/1-己烯共聚时活性可达1 576.5 g·g^-1。加入1-己烯后产物的加工性能得到改善,聚合物的熔点、密度、堆积密度和结晶度变低,相对分子质量分布从2.6拓宽至3.2,熔体流动速率从0.088 2增加至0.36 g·min^-1。

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	谷勇耀
	王立娟
	姜涛
	李健

关键词：茂金属催化剂硅胶淤浆聚合相对分子质量分布

Abstract： Metallocene polyethylene has superior properties, but its molecular weight distribution is usually narrow, which will bring a series of problems such as difficulties in subsequent molding and processing, and limit its large-scale application. In this study, a supported metallocene catalyst was obtained by using methylaluminoxane (MAO)-modified silica gel as a carrier and metallocene compound as the active component, and metallocene polyethylene was obtained by catalyzing ethylene polymerization in a slurry system. The effects of preparation conditions on loading and polymerization conditions on activity were systematically investigated, and the catalysts and polymerization products were analyzed and characterized by scanning electron microscopy, inductively coupled plasma mass spectrometry, laser particle size analyzer, and high-temperature gel permeation chromatography. The experimental results showed that the activity release of the supported catalyst was moderate, and the activity of the supported catalyst could reach 1 576.5 g·g^-1. After the addition of 1-hexene, the processing properties of the product were improved, the melting point, density, bulk density and crystallinity of the polymer became lower, the molecular weight distribution was broadened from 2.6 to 3.2, and the melt flow rate increased from 0.088 2 to 0.36 g·min^-1.

Keywords： metallocene catalysts silica gel slurry polymerization molecular weight distribution

Received 2023-12-06;

Fund:中国石油天然气集团公司关键核心项目(2022GJ17)。

Corresponding Authors: 李健,教授,E-mail:lijian@tust.edu.cn。 Email: lijian@tust.edu.cn

About author: 谷勇耀(1996—),女,硕士研究生,现从事负载型茂金属催化剂方面的研究。

引用本文:

谷勇耀, 王立娟, 姜涛, 李健.负载型茂金属催化剂用于制备宽相对分子质量分布聚乙烯的研究[J]. 化学工业与工程, 2024,41(6): 42-49

GU Yongyao, WANG Lijuan, JIANG Tao, LI Jian.Preparing supported metallocene catalysts and applying in production of polyethylene with wide molecular weight distribution[J]. Chemcial Industry and Engineering, 2024,41(6): 42-49

[1] 杨兴, 孙建友, 李京仙. 聚乙烯生产技术中催化剂研究进展[J]. 广东化工, 2014, 41(17): 107-108 YANG Xing, SUN Jianyou, LI Jingxian. Progress of catalyst research in polyethylene production technology[J]. Guangdong Chemical Industry, 2014, 41(17): 107-108(in Chinese)
[2] 李刚健, 周子淳, 张荣, 等. 聚乙烯催化剂研究现状[J]. 合成材料老化与应用, 2021, 50(2): 151-154 LI Gangjian, ZHOU Zichun, ZHANG Rong, et al. Research status of polyethylene catalyst[J]. Synthetic Materials Aging and Application, 2021, 50(2): 151-154(in Chinese)
[3] 胡程, 张连红, 文婕, 等. 茂金属烯烃聚合催化剂研究进展[J]. 广州化工, 2022, 50(13): 16-19 HU Cheng, ZHANG Lianhong, WEN Jie, et al. Research progress on metallocene olefin polymerization catalysts[J]. Guangzhou Chemical Industry, 2022, 50(13): 16-19(in Chinese)
[4] VELTHOEN M E Z, MUÑOZ-MURILLO A, BOUHMADI A, et al. The multifaceted role of methylaluminoxane in metallocene-based olefin polymerization catalysis[J]. Macromolecules, 2018, 51(2): 343-355
[5] 高宇新, 杨国兴, 吴薇, 等. 负载化茂金属催化剂的研究进展[J]. 现代塑料加工应用, 2022, 34(1): 56-59 GAO Yuxin, YANG Guoxing, WU Wei, et al. Research progress of supported metallocene catalysts[J]. Modern Plastics Processing and Applications, 2022, 34(1): 56-59(in Chinese)
[6] TRAN D, SOWAH C S, CHOI K. Effects of spatial distributions of active sites in a silica-supported metallocene catalyst on particle fragmentation and reaction in gas-phase ethylene polymerization[J]. Macromolecules, 2022, 55(7): 2444-2455
[7] BOLNER F M, BLAZZIO Y R, LARA B R, et al. Impact of silica pore structure on the performance of metallocene catalysts in ethylene gas-phase polymerization[J]. The Canadian Journal of Chemical Engineering, 2023, 101(9): 4819-4831
[8] 张倩, 葛腾杰, 姜涛, 等. 负载型茂金属催化剂用于乙烯淤浆聚合的研究[J]. 化学工业与工程, 2022, 39(6): 29-35 ZHANG Qian, GE Tengjie, JIANG Tao, et al. SMAO supported metallocene catalyst for slurry polymerization of ethylene[J]. Chemical Industry and Engineering, 2022, 39(6): 29-35(in Chinese)
[9] 高克京, 吕新平, 王世波, 等. 高效气相聚乙烯催化剂的制备[J]. 合成树脂及塑料, 2009, 26(4): 1-5 GAO Kejing, Lü Xinping, WANG Shibo, et al. Preparation of high performance catalyst for polyethylene with gas-phase fluid reactor[J]. China Synthetic Resin and Plastics, 2009, 26(4): 1-5(in Chinese)
[10] 刘彦昌. 分子量分布对聚乙烯性能的影响及控制方法[J]. 合成树脂及塑料, 1999, 16(6): 31-33 LIU Yanchang. Influence of molecular weight distribution on performance of PE product and the control measures[J]. China Synthetic Resin and Plastics, 1999, 16(6): 31-33(in Chinese)
[11] KIDA T, TANAKA R, HIEJIMA Y, et al. Improving the strength of polyethylene solids by simple controlling of the molecular weight distribution[J]. Polymer, 2021, 218: 123526
[12] 王海平. 宽/双峰相对分子质量分布聚乙烯的研究进展[J]. 齐鲁石油化工, 2006, 34(4): 431-435 WANG Haiping. Research progress of polyethylene with wide/bimodal relative molecular weight distribution[J]. Qilu Petrochemical Technology, 2006, 34(4): 431-435(in Chinese)
[13] 崔楠楠, 王洪涛, 周俊领. 复合催化剂制备宽/双峰相对分子质量分布聚乙烯[J]. 石油化工, 2017, 46(6): 691-694 CUI Nannan, WANG Hongtao, ZHOU Junling. Mixed catalyst for producing broad/bimodal relative molecular mass polyethylene[J]. Petrochemical Technology, 2017, 46(6): 691-694(in Chinese)
[14] 张林, 许学翔, 纪洪波, 等. Ziegler-Natta/非茂双金属催化剂制备宽相对分子质量分布聚乙烯[J]. 石油化工, 2005, 34(11): 1050-1054 ZHANG Lin, XU Xuexiang, JI Hongbo, et al. Ziegler-natta/non-metallocene bimetallic catalyst for preparation of broad relative molecular mass distribution polyethylene[J]. Petrochemical Technology, 2005, 34(11): 1050-1054(in Chinese)
[15] LIU Z, ZHANG X, HUANG H, et al. Synthesis of (co-) polyethylene with broad molecular weight distribution by the heterogenous Ziegler-Natta catalysts via one-pot strategy[J]. Journal of Industrial and Engineering Chemistry, 2012, 18(6): 2217-2224
[16] MEHDIABADI S, LHOST O, VANTOMME A, et al. Ethylene polymerization kinetics and microstructure of polyethylenes made with supported metallocene catalysts[J]. Industrial & Engineering Chemistry Research, 2021, 60(27): 9739-9754
[17] 任合刚, 高晶杰, 任合平, 等. 有机载体钛系催化剂在乙烯聚合中的应用[J]. 合成树脂及塑料, 2022, 39(5): 38-40 REN Hegang, GAO Jingjie, REN Heping, et al. Application of organic supported titanium catalyst system in ethylene polymerization[J]. China Synthetic Resin and Plastics, 2022, 39(5): 38-40(in Chinese)
[18] WANG W, FAN Z, FENG L, et al. Substituent effect of bisindenyl zirconene catalyst on ethylene/1-hexene copolymerization and propylene polymerization[J]. European Polymer Journal, 2005, 41(1): 83-89
[19] 米普科, 王建伟, 王立娟, 等. 碳桥限制构型催化剂催化乙烯1-己烯共聚和共聚物结构表征[J]. 分子催化, 2017, 31(6): 501-512 MI Puke, WANG Jianwei, WANG Lijuan, et al. Synthesis and characterization of copolymer of ethylene and 1-hexene by carbon bridge CpCN-CGC[J]. Journal of Molecular Catalysis (China), 2017, 31(6): 501-512(in Chinese)
[20] 张玉良, 陈志康, 蒋文军, 等. 聚合条件对乙烯-1-辛烯共聚反应及性能影响[J]. 现代塑料加工应用, 2019, 31(5): 21-23 ZHANG Yuliang, CHEN Zhikang, JIANG Wenjun, et al. Effects of polymerization conditions on copolymerization and properties of ethylene-1-octene[J]. Modern Plastics Processing and Applications, 2019, 31(5): 21-23(in Chinese)