A series of novel Ni(II) and Pd(II) complexes bearing chiral bis(β-ketoamino) ligand were synthesized characterized. The exhibited high activities for norbornene homopolymerization with only B(C 6 F 5 ) 3 as cocatalyst, complex even up to 1.38 ×10 g polymer /mol Ni ·h. All the had good thermal stability. Most importantly, also displayed 10 metal ·h toward copolymerization 5-norbornene-2-yl acet...

Two new chiral pre-ligands, (R)-3,3'-bis(tetramethylcyclopentadienyl)-2,2'-bismethoxy-1,1'-bisnaphthalene (1) and (R)-3-tetramethylcyclopentadienyl-2,2'-bismethoxy-1,1'-bisnaphthalene (2), were synthesized by reaction of (R)-3,3'-dilithium-2,2'-bismethoxy-1,1'-bisnaphthalene with 2,3,4,5-tetramethyl-2-cyclopentenone at room temperature. Treatment of the pre-ligands 1 and 2 with butyllithium and...

Highly active metallocenes and other single site catalysts have opened up the possibility of polymerizing cycloolefins such as norbornene (N) or of copolymerizing them with ethene (E) or propene (P). The polymers obtained show exciting structures and properties. E-N copolymers are industrially produced materials, with variable and high glass transitions depending on the wide range of their micr...

Herein, we report the synthesis of polyesters via the alternating copolymerization of epoxides and cis-5-norbornene-endo-2,3dicarboxylic anhydride (NB). The polymers are demonstrated to be of perfectly alternating structure with monomodal peak distributions and low polydispersity indexes. We demonstrate that these polyesters can be functionalized using thiol–ene and tetrazine click chemistry to...

highly active metallocenes and other single site catalysts have opened up the possibility of polymerizing cycloolefins such as norbornene (n) or of copolymerizing them with ethene (e) or propene (p). the polymers obtained show exciting structures and properties. e-n copolymers are industrially produced materials, with variable and high glass transitions depending on the wide range of their micr...

Statistical copolymers of norbornene (NBE) with cyclopentene (CP) were prepared by ring-opening metathesis polymerization, employing the 1st-generation Grubbs' catalyst, in the presence or absence of triphenylphosphine, PPh₃. The reactivity ratios were estimated using the Finemann-Ross, inverted Finemann-Ross, and Kelen-Tüdos graphical methods, along with the computer program COPOINT, which eva...

We describe the parallel, one-pot synthesis of core-photocleavable, poly(norbornene)-co-poly(ethylene glycol) (PEG) brush-arm star polymers (BASPs) via a route that combines the "graft-through" and "arm-first" methodologies for brush polymer and star polymer synthesis, respectively. In this method, ring-opening metathesis polymerization of a norbornene-PEG macromonomer generates small living br...

The conformational analysis of ethylene-norbornene chains (E-N) has been carried out using AM1, MM2, AMBER and OPLS methods taking into consideration the possibility of binding the ethylene monomers to norbornene monomers at various positions, i.e. exo-exo, exo-endo, endo-endo. The chain that is formed by connecting exo-endo positions of the monomers has lower torsional barrier energy than thos...

copolymerization of ethylene and propylene was investigated using a 4th generation phthalate ziegler-natta catalyst in normal hexane in a buchi reactor. the effects of different mole fractions of [al]/[ti], [si]/[al] and various amounts of hydrogen on productivity and weight percent of ethylene on the product, were studied. in the copolymerization reactions, tri-isobutyl aluminum (tibal) was us...