MICROSTRUCTURE AND PRESSURE-VOLUME-TEMPERATURE PROPERTIES OF ETHENE 1-OCTENE RANDOM COPOLYMERS/

Copolymers of ethene and 1-octene were synthesized covering the entire composition range by means of the methylalumoxane activated rac-Me2Si (2-MeBenz[e]Ind)(2)ZrCl2 catalyst. C-13-NMR spectroscopy revealed firs t-order Markov statistics to be reasonably suited for the description of the copolymer sequence distribution. Characteristic parameters of e thene/1-octene copolymers were obtained by evaluation of pressure-volu me-temperature data using the Flory-Orwoll-Vrij equation-of-state theo ry. The characteristic pressure could not be correlated with 1-octene comonomer incorporation when assuming validity of the mixing rules kno wn for homopolymer blends, whereas the characteristic specific volume and characteristic temperature are independent of copolymer compositio n within experimental errors. A possible explanation is presented for why the attempts to predict the characteristic pressure of ethene/1-oc tene copolymers from the corresponding homopolymer parameters fail usi ng Flory's mixing rules.