{"title":"Syndiotactic (Co)polymerization of 4-Vinylbenzocyclobutene Catalyzed by Rare-Earth Metal Complex","authors":"Peng Deng, Lipeng Sang, Xun Gong, Xiang Guo and Jianhua Cheng*, ","doi":"10.1021/acs.macromol.4c00958","DOIUrl":null,"url":null,"abstract":"<p >Recent years have witnessed great achievements in the coordination polymerization of various olefins catalyzed by rare-earth metal catalysts. However, the ubiquitous monomers containing a benzocyclobutene (BCB) group, which have excellent thermal properties, remain unexplored yet. Here, we report the coordination (co)polymerization of 4-vinylbenzocyclobutene (4-VBCB) by using tetraphenylcyclopentadienyl supported scandium alkyl complex [(Cp<sup>Ph4H</sup>)Sc(CH<sub>2</sub>SiMe<sub>3</sub>)<sub>2</sub>(THF)] (<b>1</b>) as a precatalyst. The high syndioselectivity (rrrr > 99%) was observed in both the resultant poly(4-VBCB)s and poly(St-<i>co</i>-VBCB)s, which are soluble in most common solvents, sharply in contrast to the typical <i>s</i>PS. Copolymerization of 4-VBCB with styrene afforded a gradient copolymer due to the dramatically different reactivity of the two monomers (<i>r</i><sub>VBCB</sub>/<i>r</i><sub>St</sub> = 84.3). Moreover, copolymerization of 4-VBCB with ethylene (2 atm) proceeded smoothly to yield ethylene-VBCB random copolymers with a variety of VBCB contents (5.2–22.7%). In the presence of maleimide, cross-linked functional polyethylene was obtained through the Diels–Alder reaction and intermolecular cross-link. More interestingly, nanoparticles based on polyethylene were successfully synthesized under ultralow concentration <i>via</i> intramolecular cross-linking of the ethylene-VBCB copolymer.</p>","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":null,"pages":null},"PeriodicalIF":5.1000,"publicationDate":"2024-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Macromolecules","FirstCategoryId":"92","ListUrlMain":"https://pubs.acs.org/doi/10.1021/acs.macromol.4c00958","RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"POLYMER SCIENCE","Score":null,"Total":0}
引用次数: 0
Abstract
Recent years have witnessed great achievements in the coordination polymerization of various olefins catalyzed by rare-earth metal catalysts. However, the ubiquitous monomers containing a benzocyclobutene (BCB) group, which have excellent thermal properties, remain unexplored yet. Here, we report the coordination (co)polymerization of 4-vinylbenzocyclobutene (4-VBCB) by using tetraphenylcyclopentadienyl supported scandium alkyl complex [(CpPh4H)Sc(CH2SiMe3)2(THF)] (1) as a precatalyst. The high syndioselectivity (rrrr > 99%) was observed in both the resultant poly(4-VBCB)s and poly(St-co-VBCB)s, which are soluble in most common solvents, sharply in contrast to the typical sPS. Copolymerization of 4-VBCB with styrene afforded a gradient copolymer due to the dramatically different reactivity of the two monomers (rVBCB/rSt = 84.3). Moreover, copolymerization of 4-VBCB with ethylene (2 atm) proceeded smoothly to yield ethylene-VBCB random copolymers with a variety of VBCB contents (5.2–22.7%). In the presence of maleimide, cross-linked functional polyethylene was obtained through the Diels–Alder reaction and intermolecular cross-link. More interestingly, nanoparticles based on polyethylene were successfully synthesized under ultralow concentration via intramolecular cross-linking of the ethylene-VBCB copolymer.
期刊介绍:
Macromolecules publishes original, fundamental, and impactful research on all aspects of polymer science. Topics of interest include synthesis (e.g., controlled polymerizations, polymerization catalysis, post polymerization modification, new monomer structures and polymer architectures, and polymerization mechanisms/kinetics analysis); phase behavior, thermodynamics, dynamic, and ordering/disordering phenomena (e.g., self-assembly, gelation, crystallization, solution/melt/solid-state characteristics); structure and properties (e.g., mechanical and rheological properties, surface/interfacial characteristics, electronic and transport properties); new state of the art characterization (e.g., spectroscopy, scattering, microscopy, rheology), simulation (e.g., Monte Carlo, molecular dynamics, multi-scale/coarse-grained modeling), and theoretical methods. Renewable/sustainable polymers, polymer networks, responsive polymers, electro-, magneto- and opto-active macromolecules, inorganic polymers, charge-transporting polymers (ion-containing, semiconducting, and conducting), nanostructured polymers, and polymer composites are also of interest. Typical papers published in Macromolecules showcase important and innovative concepts, experimental methods/observations, and theoretical/computational approaches that demonstrate a fundamental advance in the understanding of polymers.