Supported metallocene catalysts prepared by impregnation of MAO modified silica by a metallocene/monomer solution

Kamfjord, Thor; Wester, Thale Sofie; Rytter, Erling

doi:10.1002/(sici)1521-3927(19981001)19:10<505::aid-marc505>3.3.co;2-h

Cited by 4 publications

(4 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The polymerization rates of the three catalysts consist essentially of acceleration to a maximum activity followed by a continuous decline (Figs 3–5). This is consistent with the rate profiles of metallocene/MAO catalysts reported in the literature 41–45. The acceleration phase has been attributed to different induction times of individual catalyst particles caused by inhomogeneous MAO loading,46 and gradual exposure of catalyst sites due to fragmentation of the catalyst particles 47.…”

Section: Resultssupporting

confidence: 90%

Gas‐phase olefin polymerization over supported metallocene/MAO catalysts: influence of support on activity and polydispersity

Hammawa

Wanke

2006

Polymer International

View full text Add to dashboard Cite

Three catalysts obtained by supporting bis(n‐butylcyclopentadienyl)zirconium dichloride/methylaluminoxane on: (1) porous crosslinked poly(2‐hydroxyethylmethacrylate‐co‐styrene‐co‐divinylbenzene) particles (CAT1); (2) swellable crosslinked poly(styrene‐co‐divinylbenzene) particles (CAT2); and (3) by evaporating the catalyst precursors solution to dry powder, CAT3 were used in gas‐phase polymerization of ethylene, and ethylene/1‐hexene in a 2 L semi‐batch reactor at 80 °C and 1.4 MPa. The average polymerization activities of the three catalysts were 12.3–15.5, 4.2–10.1, and 14.3–62.9 ton PE (mol Zr h)−1 respectively. CAT1 and CAT3 produced polyethylenes with a polydispersity range of 2.3–2.7, while that of CAT2 was 3.5–6.4. The supported catalysts produced polyolefin particles with bulk density of 0.36–0.43 g ml−1, and essentially no fines. Ethylene/1‐hexene co‐polymerization (7 mol m−3 initial 1‐hexene concentration in the reactor) increased polymerization activities and produced lower‐molar‐mass co‐polymers. At 21 mol m−3 1‐hexene the polymerization activities decreased, but the relative amount of the low‐molar‐mass co‐polymer for CAT2 increased, leading to higher polydispersity. Copyright © 2006 Society of Chemical Industry

show abstract

Section: Resultssupporting

confidence: 90%

Gas‐phase olefin polymerization over supported metallocene/MAO catalysts: influence of support on activity and polydispersity

Hammawa

Wanke

2006

Polymer International

View full text Add to dashboard Cite

show abstract

“…Silica-supported MAO has been treated by Rytter et al with ( Bu Cp) 2 ZrCl 2 dissolved in a liquid α-olefin (1-hexene, 1-octene, or styrene) using the pore-filling technique described above for the impregnation of MAO onto silica . Instead of evaporation, the solvent is allowed to polymerize, affording catalyst particles that were protected from oxidation.…”

Section: 32 Supporting An Aluminoxanementioning

confidence: 99%

“Bound but Not Gagged”Immobilizing Single-Site α-Olefin Polymerization Catalysts

et al. 2005

View full text Add to dashboard Cite

“…Alumina is an inorganic oxide studied often as support for the metallocene catalysts and γ‐alumina is the type that is most frequently used 8–12. Furthermore, as silica is available in a large range of particle size and pore‐size distribution and, because of these ranges can be controlled during its synthesis, this solid material is also one of the inorganic oxides that is greatly explored in research as support for the metallocene catalysts 7–10, 12–22…”

Section: Introductionmentioning

confidence: 99%

The influence of the preparing conditions of SiO₂ supported Cp₂ZrCl₂ catalyst on ethylene polymerization

Marques

Conte

2002

J of Applied Polymer Sci

View full text Add to dashboard Cite

ABSTRACT:In this work, ethylene was polymerized by using Cp 2 ZrCl 2 supported on silica pretreated with methylaluminoxane (MAO) as the catalyst system. The influence of the conditions for the preparation of the heterogeneous catalyst, such as temperature, washing method of the catalytic solid, MAO and metallocene concentration in the support treatment, time of MAO, and metallocene immobilization on the support, type of alkylaluminum used in the support pretreatment, and calcination temperature of the support were investigated. Aluminum and zirconium content fixed on the silica surface were determined by inductively coupled plasma emission spectroscopy. Polymer characteristics were determined by gel permeation chromatography and differential scanning calorimetry. According to the results, the activity of some supported catalysts were far higher than with the homogeneous system. Moreover, polyethylene with very high molecular weights were also obtained and with molecular weight distribution larger than those produced with the homogeneous precursor.

show abstract

Supported metallocene catalysts prepared by impregnation of MAO modified silica by a metallocene/monomer solution

Cited by 4 publications

References 0 publications

Gas‐phase olefin polymerization over supported metallocene/MAO catalysts: influence of support on activity and polydispersity

Gas‐phase olefin polymerization over supported metallocene/MAO catalysts: influence of support on activity and polydispersity

“Bound but Not Gagged”Immobilizing Single-Site α-Olefin Polymerization Catalysts

The influence of the preparing conditions of SiO₂ supported Cp₂ZrCl₂ catalyst on ethylene polymerization

Contact Info

Product

Resources

About

Supported metallocene catalysts prepared by impregnation of MAO modified silica by a metallocene/monomer solution

Cited by 4 publications

References 0 publications

Gas‐phase olefin polymerization over supported metallocene/MAO catalysts: influence of support on activity and polydispersity

Gas‐phase olefin polymerization over supported metallocene/MAO catalysts: influence of support on activity and polydispersity

“Bound but Not Gagged”Immobilizing Single-Site α-Olefin Polymerization Catalysts

The influence of the preparing conditions of SiO2 supported Cp2ZrCl2 catalyst on ethylene polymerization

Contact Info

Product

Resources

About

The influence of the preparing conditions of SiO₂ supported Cp₂ZrCl₂ catalyst on ethylene polymerization