The distribution of configurations in (predominantly) isotactic polypropylene samples obtained with heterogeneous Ziegler-Natta catalyst systems, investigated by means of high-field 13C NMR, reveals deviations from that predicted by the simple "enantiomorphic-site" model commonly used to describe it. Such deviations suggest that the "active socket" in these systems is similar to that of the new homogeneous isotactic-selective catalysts based on C1-sym. ansa-metallocenes of the 4th column. This provides, inter alia, a common explanation for the increase of stereoselectivity with decreasing monomer concn. obsd. for both catalyst classes
Results of a 13C NMR study of polypropene and ethene (I)-propene copolymers (I content <2%) prepd. i...
Homogeneous catalysts for propylene polymerization are now available for production of isotactic po...
We report the results of a 150 MHz 13C NMR characterization of ethene-1-13C/propene copolymers at lo...
The distribution of configurations in (predominantly) isotactic polypropylene samples obtained with ...
13CNMRspectroscopyisthemainsourceofinformationonthestereochemistryofZiegler- Natta and related trans...
13C NMR spectroscopy is the main source of information on the stereochem. of Ziegler-Natta- and rela...
The stereoregularity of polypropylene produced with C2-sym. group 4 ansa-metallocene catalysts resul...
The stereochemistry of polypropenes obtained in the presence of several MgCl2-supported Ziegler-Natt...
The main results of a high-resoln. 150 MHz 13C NMR characterization of polypropene samples prepd. in...
The stereosequence distribution of the "atactic" and "isotactic" fractions of a polypropylene sample...
The stereosequence distribution of the "atactic" and "isotactic" fractions of a polypropylene sample...
Results of a 13C NMR study of polypropene and ethene (I)-propene copolymers (I content <2%) prepd. i...
Homogeneous catalysts for propylene polymerization are now available for production of isotactic po...
We report the results of a 150 MHz 13C NMR characterization of ethene-1-13C/propene copolymers at lo...
The distribution of configurations in (predominantly) isotactic polypropylene samples obtained with ...
13CNMRspectroscopyisthemainsourceofinformationonthestereochemistryofZiegler- Natta and related trans...
13C NMR spectroscopy is the main source of information on the stereochem. of Ziegler-Natta- and rela...
The stereoregularity of polypropylene produced with C2-sym. group 4 ansa-metallocene catalysts resul...
The stereochemistry of polypropenes obtained in the presence of several MgCl2-supported Ziegler-Natt...
The main results of a high-resoln. 150 MHz 13C NMR characterization of polypropene samples prepd. in...
The stereosequence distribution of the "atactic" and "isotactic" fractions of a polypropylene sample...
The stereosequence distribution of the "atactic" and "isotactic" fractions of a polypropylene sample...
Results of a 13C NMR study of polypropene and ethene (I)-propene copolymers (I content <2%) prepd. i...
Homogeneous catalysts for propylene polymerization are now available for production of isotactic po...
We report the results of a 150 MHz 13C NMR characterization of ethene-1-13C/propene copolymers at lo...