Preparation of silyl-terminated branched polyethylenes catalyzed by Brookhart's nickel diimine complex activated with hydrosilane/B(C6F5)3

0583981 - ÚFCH JH 2025 RIV GB eng J - Článek v odborném periodiku
Varga, Vojtěch - Pokorná, K. - Lamač, Martin - Horáček, Michal - Pinkas, Jiří
Preparation of silyl-terminated branched polyethylenes catalyzed by Brookhart's nickel diimine complex activated with hydrosilane/B(C6F5)3.
Dalton Transactions. Roč. 53, č. 11 (2024), s. 5249-5257. ISSN 1477-9226. E-ISSN 1477-9234
Grant CEP: GA ČR(CZ) GA21-01308S
Institucionální podpora: RVO:61388955
Klíčová slova: Polyethylenes * Nickel compounds * Silicon
Obor OECD: Physical chemistry
Impakt faktor: 4, rok: 2022
Způsob publikování: Open access
https://pubs.rsc.org/en/content/articlelanding/2024/dt/d3dt04200f

Brookhart's nickel alpha-diimine complex [(kappa2-N,N-BIAN)NiCl2] (1) (where BIAN = {Ar-NAceN-Ar}, Ace = acenaphthen-1,2-diyl, and Ar = 2,6-(iPr)2-C6H3) activated with a hydrosilane/B(C6F5)3 (SiHB) adduct forms a highly active catalytic system for ethylene polymerization. Under optimal conditions, the activity of the system depends on the nature of hydrosilane and decreases in the order R3SiH > Ph2SiH2 > PhSiH3. The decrease in system activity within the hydrosilane series is correlated with increasing formation of Ni(I) species. In addition to their activation effect, hydrosilanes act as efficient chain termination/chain transfer agents, with the Si/Ni ratio controlling the molecular weight of the resulting polyethylene (PE). The use of Et3SiH generated elastomeric, highly branched polymers with a saturated chain-end, while systems using Ph2SiH2 and PhSiH3 led to branched end-functionalized PEs terminated with the hydrosilyl functionality (i.e. br-PE-SiPh2H or br-PE-SiPhH2).
Trvalý link: https://hdl.handle.net/11104/0351975