Facile, Efficient Copolymerization of Ethylene with Bicyclic, Non‐Conjugated Dienes by Titanium Complexes Bearing Bis(β‐Enaminoketonato) Ligands

Abstract

Copolymerizations of ethylene with 5-vinyl-2-norbornene or 5-ethylidene-2-norbornene under the action of various titanium complexes bearing bis(b-enaminoketonato) chelate ligands of the type,, have been shown to occur with the regioselective insertion of the endocyclic double bond of the monomer into the copolymer chain, leaving the exocyclic vinyl double bond as a pendant unsaturation. The ligand modification strongly affects the copolymerization behaviour. High catalytic activities and efficient co-monomer incorporation can be easily obtained by optimizing the catalyst structures and polymerization conditions.

Facile, Efficient Copolymerization of Ethylene with Norbornene-Containing Dienes Promoted by Single Site Non-Metallocene Oxovanadium(V) Catalytic System

“…to vanadium complexes) was employed as reactivating agent; a VNB incorporations were (mol %) calculated from 1 H NMR spectra; b Weight-average molecular weight (Mw) and polydispersity indexes (PDI) of the copolymers were determined by high temperature The incorporations and stereoselectivity of VNB were unambiguously revealed by 1 H, 13 C, and DEPT NMR spectra. All resonances were clearly identified and the data agreed well with the previously reported values [15,16]. No signals around 6.1 ppm relative to the C=C double bond of norbornene presented, while the resonances between 4.8 and 6.0 ppm corresponding to the pendant vinyl groups could be observed in the l H NMR spectra of the copolymers.…”

“…The COCs containing high density polyethylene (HDPE) and PP, and exceptional moisture barrier for a clear polymer along with low moisture absorption rate. The COCs containing the reactive olefin groups are expected to provide functional COCs with substantially improved properties, and thus have attracted increasing attentions [13][14][15][16][17][18][19][20][21][22]. Several catalytic systems, including Ziegler-Natta catalysts [21], metallocenes [15] and non-metallocenes [13,14,16], have demonstrated good performance in the copolymerization of ethylene with various cyclic dienes.…”

Efficient copolymerization of ethylene with norbornene or its derivatives using half-metallocene zirconium(iv) catalysts

“…It conrms the conclusion again that aluminum alkyls do play important and complicated role for these catalysts in ethylene/ NBE-derivates copolymerization, similar to the situation previously reported. 11 It may be ascribed to the different exocyclic double bond in VNB. This may be determined by the MW and microstructure of copolymers, which is the same as E/NBE copolymers.…”

“…1,2 The existence of ring strain in the structure of norbornene (NBE) and its derivatives makes them facile polymerizable, thus NBE has become one of the most active participants in ethylene/cyclo-olen copolymerization. 7,[9][10][11][12][13][14][15][16][17][18][19] Catalysts play a crucial role in the production of ethylene/ ENB or ethylene/VNB copolymers, and most of catalysts reported are ansa-metallocenes. As the simplest method of functionalization, copolymerization of olen with polar monomer using early transition metal catalysts is rarely reported because of the highly oxophilic nature of polar monomer.…”

Living regioselective copolymerization of ethylene with nonconjugated bicyclic dienes using (salicylaldiminato)(β‐enaminoketonato) titanium catalysts

“…In particular, the copolymers from ethylene and cyclodiolefins have become more attractive recently, because the further functionalization of the remaining CC double bonds in the copolymers could be possible to afford a broad range of new functional polymers with improved properties through chemical modification 24–27. So far, many studies about the copolymerization of ethylene with cyclodiolefins like 1,3‐cyclohexadiene,28, 29 2,5‐norbornadiene,30, 31 dicyclopentadiene,31–35 1,3‐cyclopentadiene,35 5‐vinyl‐2‐norbornene (VNB),36–42 or 5‐ethylidene‐2‐norbornene (ENB)43–48 have been carried out and reported, but most of the catalysts used were limited to metallocene 49. Furthermore, successful examples for controlled/living ethylene/cyclodiolefin copolymerizations remained scarce 50–53.…”