Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Syntheses of poly(siloxane)-supported zirconocene catalysts and application to olefin polymerizations (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 421-428 
    Details
    ISSN: 0887-624X
    Keywords: poly(siloxane)-supported zirconocene catalysts ; polymerizations of ethene and propene ; copolymerization of ethene with 1-octene ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Poly(siloxane)s with bisindenyl, bisfluorenyl, bis(1,2,3,4-tetramethylcyclopentadienyl), bis(2,4,7-trimethylindenyl) and monoindenylmethyl side groups were synthesized by condensation of the corresponding dichlorosilanes and water. For reference, diphenylsilanediol or hydroquinone was also employed in place of water. A series of poly(siloxane)-supported zirconocene catalysts were then prepared from these precursors and applied to ethene and propene polymerizations as well as to the copolymerization of ethene with 1-octene in the presence of methylalumoxane. The polymerization activity of the new supported metallocenes depends drastically upon the substituents in the siloxane backbone. The zirconocene catalysts supported on poly(bisindenylsiloxane) and poly(bisfluorenylsiloxane) give the highest activities for ethene and propene polymerizations, respectively. The weight-average molecular weights of the polymers are also markedly dependent upon the substituents. On the other hand, the molecular mass distributions (MMD) are generally not so sharp, suggesting that the active species formed in these supported catalysts are not uniform. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 421-428, 1998
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
  • 2
    Electronic Resource
    Electronic Resource
    Polymerization of 1,3-butadiene with MgCl2-supported cobalt catalysts activated by ordinary alkylaluminums (1995)
    New York, NY [u.a.] : Wiley-Blackwell
    Polymer International 36 (1995), S. 41-45 
    Details
    ISSN: 0959-8103
    Keywords: polymerization of 1,3-butadiene ; MgCl2-supported CoBr2 catalysts ; control of 1,2-content ; triphenylphosphine ; dimethoxydiphenylsilane ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: MgCl2-supported CoBr2 catalysts were prepared from mixture of MgCl2 and CoBr2L2 (L = triphenylphosphine or pyridine) in toluene. Polymerization of 1,3-butadiene was conducted over the catalysts combined with ordinary alkylaluminums as cocatalyst. The CoBr2(PPh3)2/MgCl2 catalyst gave polybutadiene with approximately 80% of 1,2 units, whereas cis-1,4-poly-butadiene was obtained with the CoBr2(C5H5N)2/MgCl2 catalyst.Addition of triphenylphospine to the latter catalyst caused a marked increase in the content of 1,2 units. The content of 1,2 units could be thus controlled in the range from 0 to 80% by changing the amount of triphenylphosphine.On the other hand, the CoBr2(PPh3)2/MgCl2 catalyst with very low content of CoBr2(PPh3)2 hardly displayed any activity. Addition of dimethoxydiphenylsilane to the catalyst gave polybutadiene containing 90 % of 1,2 units with a fairly high activity.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pi.1995.210360107
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...