| Abstract: | Homogeneous copolymers of ethylene and 1-alkenes have been prepared using an ethyl aluminum sesquichloride–vanadium oxychloride catalyst system. Branches were varied from CH3 to C16H33 by appropriate choice of 1-alkene. Size exclusion studies of copolymers of ethylene-d4 and 1-alkenes show that the comonomer content of a given sample is essentially constant over the whole molecular weight range. A random distribution of branches is inferred from the simplicity of the 13C-NMR spectra and from the melting behaviour of the copolymers. Comonomer contents varying from 1 mol% to 15 mol% were readily determined by 13C-NMR spectroscopy. The copolymers can be used to study the separate effects of branch length, branch frequency, and molecular weight on physical properties including melting point and crystallinity. |
