Polymerization of 1,3-cyclohexadiene with nickel/MAO catalytic systems

Pò, Riccardo; Santi, R.; Cardaci, Maria Anna

doi:10.1002/1099-0518(20000815)38:16<3004::aid-pola180>3.0.co;2-j

Cited by 13 publications

(5 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Since the discovery of Ziegler‐Natta catalysts, it has been a long scientific interest and technologically important subject to investigate the routes to incorporate functional groups into a polyolefin chain 1–4. In recent years, the precise and efficient synthesis of polyethylene bearing double bonds via copolymerization of ethylene with dienes, such as aromatic dienes, linear dienes, and cyclic dienes, has attracted wide attention because the retained double bonds can be converted into the functional groups affording functional polyethylene with improved performance 5–10.…”

Section: Introductionmentioning

confidence: 99%

Facile, efficient functionalization of polyethylene via regioselective copolymerization of ethylene with cyclic dienes

Miao

Pan

et al. 2010

J. Polym. Sci. A Polym. Chem.

View full text Add to dashboard Cite

The copolymerizations of ethylene with cyclic dienes [dicyclopentadiene (DCPD) and 2,5-norbornadiene (NBD)] using bis(b-enaminoketonato)titanium complexesIn the presence of modified methylaluminoxane, these complexes exhibited high catalytic activities in the copolymerization of ethylene with DCPD or NBD, affording high molecular weight copolymers with unimodal molecular weight distributions. 1 H and 13 C-NMR spectra reveal ethylene/DCPD copolymerizations by catalysts 1a-c proceeds through the enchainment of norbornene ring. Catalysts 1a and 1c showed a tendency to afford alternating copolymers. More noticeably, catalysts 1b and 1c bearing bulky substituents on the ligands promote ethylene/NBD copolymerization without crosslinking, affording the copolymer containing intracyclic double bonds. The NBD incorporation as high as 27.2 mol % has been achieved by catalyst 1c. Moreover, the microstructures of the copolymers were further confirmed by the measurement of reactivity ratios and dyad monomer sequences as well as mean sequence lengths. The intracyclic double bonds of ethylene/DCPD or ethylene/NBD copolymers can be fully converted into polar groups such as epoxy, amine, silane, and hydroxyl groups under mild conditions. Convenient synthesis of hydroxylated polyethylene can be provided for the first time through the ring opening reaction of epoxide.

show abstract

Section: Introductionmentioning

confidence: 99%

Facile, efficient functionalization of polyethylene via regioselective copolymerization of ethylene with cyclic dienes

Miao

Pan

et al. 2010

J. Polym. Sci. A Polym. Chem.

View full text Add to dashboard Cite

show abstract

“…The DSC trace (Figure 2) of the insoluble PCHD with calculated number‐average molecular weight of 3 000 showed an endothermic peak at 178 °C (enthalpy = 15.45 J · g −1 ) and a glass transition temperature at 80 °C. The melting temperatures for highly crystalline PCHDs formed using transition metal catalysts were reported to be about 32029 and 315 °C,30 which are close to their decomposition temperature. The reason why the melting temperature (178 °C) of the anionically prepared PCHD is lower than those results might be because of the lower regularity (only 76% cis planomer) that would lead to lower crystallinity.…”

Section: Resultsmentioning

confidence: 80%

“…Crystalline PCHD has been made with nickel catalysts such as the π ‐allyl complex of nickel,28 Ni(acac) 2 ‐MAO (acac = acetylacetone, MAO = methylaluminoxane),29 Cp 2 Ni‐MAO (Cp = cyclopentadienyl),30 bis(allylnickel bromide/MAO),31 and bis[(allyl)trifluoroacetatonickel( II )]32 catalytic systems. The X‐ray powder diffraction profile of crystalline PCHD prepared from Cp 2 Ni‐MAO showed three crystalline peaks, positioned at 2 θ values of 16.6, 19.6 and 22.5°,30 which are very close to the results reported herein for the insoluble PCHD fraction.…”

Section: Resultsmentioning

confidence: 99%

Anionic Polymerization of Cyclohexa‐1,3‐diene in Cyclohexane with High Stereoregularity and the Formation of Crystalline Poly(cyclohexa‐1,3‐diene)

Quirk¹,

You²,

Zhu³

et al. 2003

Macro Chemistry & Physics

View full text Add to dashboard Cite

Polymerization of cyclohexa‐1,3‐diene using sec‐BuLi as initiator in cyclohexane produces both soluble (70–90 wt.‐%) and insoluble (10–30 wt.‐%) fractions depending on the temperature. The insoluble poly(cyclohexa‐1,3‐diene) was crystalline as determined by X‐ray diffraction and differential scanning calorimetry analysis (Tm = 178 °C). Both fractions were characterized by size exclusion chromatography and by 1H NMR and 13C NMR spectroscopy. The microstructures of both fractions were determined by high‐resolution 1H NMR and quantitative 13C NMR spectroscopy and compared to those poly(cyclohexa‐1,3‐diene)s prepared in benzene and in cyclohexane with 1,4‐diazobicyclo[2.2.2]octane (DABCO) as additive. The amount of 1,4‐addition of the insoluble fraction in cyclohexane was ≥ 97% and the cis planomer content was higher in cyclohexane than in benzene or in cyclohexane with DABCO as additive.

show abstract

“…[12,21] DMN (2) and DCN (3) show lower activities, which could result from their higher steric hindrance at the catalytically active center. In comparison to the Brookhart type catalyst 2 the camphor-derived diimine complex 3 was four to five times more active, despite a lower polymerization temperature.…”

Section: Resultsmentioning

confidence: 99%

Catalytic 1,3‐Cyclohexadiene Homopolymerization and Regioselective Copolymerization with Ethylene

Heiser

Okuda

Gambarotta

et al. 2005

Macro Chemistry & Physics

View full text Add to dashboard Cite

Summary: 1,3‐Cyclohexadiene (CHD) was homo‐ and copolymerized by means of diimine nickel complexes and various substituted titanium based half‐sandwich complexes activated with methylaluminoxane (MAO). Soluble polycyclohexadienes were produced with the constrained geometry catalyst [Me2Si(NtBu)(Me4Cp)]TiCl2 (CBT) (Cp = cyclopentadienyl, Me = methyl). Only in the presence of CBT/MAO soluble high molecular weight CHD copolymers with ethylene were obtained. The CHD incorporation was varied between 0 and 12.3 mol‐%. According to NMR analysis the CHD/ethylene copolymerization is highly regioselective, accounting for exclusive formation of 1,4‐cyclohexene units randomly distributed in the polyethylene backbone.13C NMR spectra of 1,4‐poly(1,3‐cyclohexadiene‐co‐ethylene) with 6.8 mol‐% CHD content in the copolymer.magnified image13C NMR spectra of 1,4‐poly(1,3‐cyclohexadiene‐co‐ethylene) with 6.8 mol‐% CHD content in the copolymer.

show abstract

Polymerization of 1,3-cyclohexadiene with nickel/MAO catalytic systems

Cited by 13 publications

References 15 publications

Facile, efficient functionalization of polyethylene via regioselective copolymerization of ethylene with cyclic dienes

Facile, efficient functionalization of polyethylene via regioselective copolymerization of ethylene with cyclic dienes

Anionic Polymerization of Cyclohexa‐1,3‐diene in Cyclohexane with High Stereoregularity and the Formation of Crystalline Poly(cyclohexa‐1,3‐diene)

Catalytic 1,3‐Cyclohexadiene Homopolymerization and Regioselective Copolymerization with Ethylene

Contact Info

Product

Resources

About