Ziegler-Natta催化剂催化丙烯聚合的动力学--催化聚合扩散控制的影响机理

Polymerization Kinetics of Propylene Catalyzed by Ziegler-Natta Catalysts --The Influence Mechanism of Diffusion Control on Catalytic Polymerization

摘要

研究了颗粒型Ziegler-Natta(Z-N)催化剂(Cat-P)及采用不同分散介质配制的Cat-P浆液催化剂(Cat-M1和Cat-M2)催化丙烯的聚合行为.研究发现，Cat-P表现出最快的活性释放、最高的催化活性与聚丙烯(PP)等规度，且PP细粉含量最低(0.6%，质量分数)；而浆液催化剂Cat-M1催化活性最低，合成的PP细粉含量最高(10.7%)、等规度最低；通过调控M1的黏度与表面张力，制备了浆液催化剂Cat-M2，与Cat-M1相比，其催化活性高，制备的PP等规度提高且细粉含量降低.研究发现，高黏度、高表面张力的分散介质会阻碍助催化剂、外给电子体及丙烯单体等向催化剂颗粒内部的扩散，扩散控制使得高立构规整性活性中心形成缓慢，同时由于活性中心附近单体供应不足，导致部分活性中心被烷基铝过度还原而失活，因此Cat-M1聚合初期活性降低、等规度下降并产生大量细粉.颗粒型Cat-P及改性的Cat-M2催化剂有利于钛活性中心的快速引发与聚合，迅速形成的长聚合物链可有效发挥“卫兵效应”，保护活性中心，防止失活.本文阐明了非均相Ziegler-Natta催化剂活化过程中的扩散控制效应，为工业烯烃聚合的稳定控制提供了理论依据.

Abstract

This study investigated the propylene polymerization behaviors using particulate Ziegler-Natta (Z-N) catalyst (Cat-P) and slurry Z-N catalysts (Cat-M1 and Cat-M2) derived from Cat-P with different dispersion media.The results demonstrated that Cat-P exhibited the fastest activation, the highest catalytic activity and yielded polypropylene (PP) with the highest isotacticity and the lowest fine powder content (0.6%, mass fraction) .In contrast, the slurry catalyst Cat-M1 showed the lowest catalytic activity and produced PP with the highest fine powder content (10.7%) and the lowest isotacticity.The slurry catalyst Cat-M2, prepared by modifying the viscosity and surface tension of dispersion medium M1, exhibited higher catalytic activity, improved isotacticity, and reduced fine powder content compared to Cat-M1.The study elucidated that the dispersion medium with high viscosity and surface tension impeded the diffusion of co-catalyst, external donor, and propylene monomer into the catalyst particles.Diffusion control slowed the formation of highly stereospecific active sites, while also leading to insufficient monomer supply locally, which in turn facilitated the deactivation of some active sitesvia further reduction by alkylaluminum.Consequently, Cat-M1 exhibited lower initial activity, decreased isotacticity, and increased fine powder generation during the early polymerization stage.The particulate Cat-P and modified Cat-M2 catalysts allowed for rapid initiation and polymerization at the Ti active sites.The rapidly growing polymer chains effectively exerted a “guard effect” to protect the active sites from deactivation.This work clarified the diffusion-controlled effects during the activation and chain propagation of heterogeneous Z-N catalysts, providing a theoretical basis for the stable control of industrial olefin polymerization.

关键词

浆液催化剂 / Ziegler-Natta催化剂 / 丙烯 / 扩散控制 / 卫兵效应

Key words

Slurry catalyst / Ziegler-Natta catalyst / Propylene / Diffusion control / Guard effect

参考文献

[1] Ziegler K., Gellert H. G., Zosel K., Lehmkuhl W., Pfohl W., Angew. Chem., 1955, 67(16), 424

[2] Natta G., J. Polym. Sci., Part A: Polym. Chem., 1996, 34(4), 321-332

[3] Meng G. M., China Synth. Resin Plast., 2018, 35(6), 53-58

[4] (孟光敏. 合成树脂及塑料, 2018, 35(6), 53-58)

[5] Yin Z. B., Wei X. L., Pet. Ind. Technol., 2014, 21(1), 53-56

[6] (殷志宝, 魏旭礼. 石化技术, 2014, 21(1), 53-56)

[7] Guo N., Yu S. J., Chai Z. X., Li Y. Y., Guo Y., Shanghai Chem. Ind., 2015, 40(9), 5-8

[8] (郭宁, 余世炯, 柴子晓, 李阳阳, 郭宇. 上海化工, 2015, 40(9), 5-8)

[9] Morra E., Giamello E., Doorslaer S. V., Antinucci G., D’Amore M., Busico V., Chiesa M., Angew. Chem., 2015, 127(16), 4939-4942

[10] Mikenas T. B., Koshevoy E. I., Zakharov V. A., Nikolaeva M. I., Macromol. Chem. Phys., 2014, 215(18), 1707-1720

[11] Luo S. F., Zhao Y. J., Wang S., Zhou R. C., Yang X., He A. H., Chem. J. Chinese Universities, 2025, 46(8), 20250067

[12] (罗淑芳, 赵远进, 王硕, 周润川, 杨霞, 贺爱华. 高等学校化学学报, 2025, 46(8), 20250067)

[13] Zhang J. Y., Peng W., He A. H., Polymer, 2020, 203, 122766

[14] Zhang H. X., Lee Y. J., Park J. R., Lee D. H., Yoon K. B., J. Appl. Polym. Sci., 2011, 120, 101-108

[15] Vittoria A., Meppelder A., Friederichs N., Busico V., Cipullo R., ACS Catal., 2017, 7(7), 4509-4518

[16] Shen X. R., Fu Z. S., Hu J., Wang Q., Fan Z. Q., J. Phys. Chem. C, 2013, 117, 15174-15182

[17] Zhou C. S., Zhao Y. J., Han M. C., Yang X., Liu C. G., He A. H., Chem. J. Chinese Universities, 2022, 43(10), 20220290

[18] (周成思, 赵远进, 韩美晨, 杨霞, 刘晨光, 贺爱华. 高等学校化学学报, 2022, 43(10), 20220290)

[19] Busico V., Chadwick J. C., Cipullo R., Ronca S., Talarico G., Macromolecules, 2004, 37(20), 7437-7443

[20] Liu B. P., Matsuoka H., Terano M., Macromol. Rapid Commun., 2001, 22, 1-24

[21] Alizadeh A., Mckenna T. F. L., Macromol. React. Eng., 2017, 12(1), 1700027

[22] Zheng W. P., Ma Y. P., Du D. L., He A. H., Shao H. F., Liu C. G., Chinese J. Polym. Sci., 2021, 39, 70-80

[23] Zhang Z., Jiang B. Y., He F., Fu Z. S., Xu J. T., Fan Z. Q., Polymers, 2019, 11(2), 358

[24] Kakugo M., Sadatoshi H., Sakai J., Yokoyama M., Macromolecules, 1989, 22(7), 3172-3177

[25] Debling J. A., Ray W. H., J. Appl. Polym. Sci., 2001, 81(13), 3085-3106

[26] Urdampilleta I., Gonzalez A., Iruin J. J., de la Cal J. C., Asua J. M., Macromolecules, 2005, 38(7), 2795-2801

[27] Dong Q., Wang X. F., Fu Z. S., Xu J. T., Fan Z. Q., Polymer, 2007, 48(20), 5905-5916

[28] Cecchin G., Marchetti E., Baruzzi G., Macromol. Chem. Phys., 2001, 202(10), 1987-1994

[29] Han M. C., Zhao Y. J., Luo S. F., Fan X. Z., He A. H., Mol. Catal., 2023, 537, 11293

[30] Kim S. H., Vurens G., Somorjai G. A., J. Catal., 2000, 193, 171-175

[31] Simon A., Fezler G., Szonyi A., Eur. Polym. J., 1977, 15, 27-28

[32] Murayama N., Liu B., Nakatani H., Terano M., Polym. Int., 2004, 53, 723-727

[33] Liu B. P., Murayama N., Terano M., Ind. Eng. Chem. Res., 2005, 44, 2382-2388

[34] Soga K., Ohgizawa M., Shiono T., Makromol. Chem., 1993, 194, 2173-2181

[35] Piovano A., Wada T., Amodio A., Takasao G., Ikeda T., Zhu D., Terano M., Chammingkwan P., Groppo E., Taniike T., ACS Catal., 2021, 11, 13782-13796

[36] Peng W. The Diene Polymerization Catalyzed by Heterogeneous Ziegler-Natta Catalyst, Qingdao University of Science and Technology, Qingdao, 2020

[37] (彭伟. 非均相Ziegler-Natta催化剂催化二烯烃聚合研究, 青岛: 青岛科技大学, 2020)

[38] Funako T., Chammingkwan P., Taniike T., Terano M., Macromol. React. Eng., 2015, 9, 325-332

[39] Chumachenko N. N., Zakharov V. A., Bukatov G. D., Sergeev S. A., Appl. Catal. A-Gen., 2014, 469, 512-516

[40] Taniike T., Funako T., Terano M., J. Catal., 2014, 31, 33-40

[41] Thakur A., Chammingkwan P., Wada T., Onishi R., Kamimura W., Seenivasan K., Terano M., Taniike T., Appl. Catal. A-Gen., 2021, 611, 117971

[42] Hu M., Jiang X. H., Absar M., Choi S., Kozak D., Shen M. Y., Weng Y. T., Zhao L., Lionberger R., AAPS J., 2018, 20(3), 62

[43] Yang S. L., Fan Z. Q., Feng L. X., Acta Polym. Sin., 1987, (5), 347-351

[44] (杨士林, 范志强, 封麟先. 高分子学报, 1987, (5), 347-351)

基金资助

泰山学者工程、国家重点研发计划项目(2022YFB3704700(2022YFB3704702))

山东省重大科技创新工程项目(2021CXGC010901)