Groups 3 and 4 single-site catalysts for styrene–ethylene and styrene–α-olefin copolymerization

Highly fluorous zirconocene(IV) complexes and their catalytic applications in the polymerization of ethylene

“…This distribution of the methyl groups in 5a causes the centroideZrecentroid angle to be the smallest (127.9 ) among the former compounds (129.6 and 130.8 in 4a and Zr{h 5 -C 5 H 4 (SiMe 3 ) 2 } 2 Cl 2 , respectively), in order to minimize steric repulsion between the methyl and the chloride ligands. The CleZreCl 0 angle of 97.35 (5) is similar to that of the catalytically active Zr(h 5 -C 5 H 5 ) 2 Cl 2 (97 ) and complex 4a (96.50 (3) ). As previously found for the related titanocene derivatives [32] and a fluorous rhodium diphosphine complex [40], the fluoroalkyl chains of neighboring molecules line up, thus creating separate domains that contain either fluoroalkyl chains or zirconocene units (Fig.…”

A Precision Ethylene‐Styrene Copolymer with High Styrene Content from Ring‐Opening Metathesis Polymerization of 4‐Phenylcyclopentene

“…Although polyethylene and polystyrene are ubiquitous plastics, synthesis of ethylene‐styrene (ES) copolymers have been historically challenging due to the markedly different monomer reactivities and, for many years, were deemed non‐viable with the limitations of traditional Ziegler–Natta catalyst systems . The advent of well‐defined “single‐site” or molecular catalysts over the last few decades has brought new attention to the efficacy and utility of ES copolymers . A broad scope of material properties are realized when traversing from low to high styrene (S) content which translates to a variety of applications for compatibilizers, packaging, films, foams, automobiles, construction materials, and bitumen modifiers .…”

Half-Titanocenes Containing Anionic Ancillary Donor Ligands: Effective Catalyst Precursors for Ethylene/Styrene Copolymerization

“…; X = halogen, alkyl), are effective not only for syndiospecific styrene polymerization, but also for ethylene/styrene copolymerization to exclusively give poly(ethylene-co-styrene)s [15,17,[52][53][54][55][56][57][58][59][60][61][62][63]. Linked halftitanocenes (so-called "constrained geometry type") are also effective for copolymerization [5,[64][65][66][67][68][69][70][71][72][73][74][75][76][77], although these complexes exhibited extremely low catalytic activities for styrene polymerization [64,73]. In this reviewing article, I wish to summarize reported examples for copolymerization, especially using modified half-titanocene catalysts [78,79].…”