The preparation and characterization of homogeneous copolymers of ethylene and 1‐alkenes

Abstract

Abstract Homogeneous copolymers of ethylene and 1‐alkenes have been prepared using an ethyl aluminum sesquichloride–vanadium oxychloride catalyst system. Branches were varied from CH 3 to C 16 H 33 by appropriate choice of 1‐alkene. Size exclusion studies of copolymers of ethylene‐d 4 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 13 C‐NMR spectra and from the melting behaviour of the copolymers. Comonomer contents varying from 1 mol% to 15 mol% were readily determined by 13 C‐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.