OPTIMIZATION OF OLEFIN COPOLYMERIZATION - EFFECTS OF REACTION PARAMETERS ON CATALYTIC ACTIVITY AND PROPERTIES

The copolymerization of ethylene with 1-hexene using Et[lnd](2)ZrCl2/M AO as catalyst was studied by multivariate methods. Three complete fac torial designs were performed to study the influence of 1-hexene conce ntration, reaction temperature and [AI]/[Zr] ratio on catalytic activi ty, copolymer viscosity, crystallinity and melting point. Since the [A I]/[Zr] ratio has a small effect on the catalytic activity, a fourth d esign with 1-hexene and temperature was developed, giving higher catal ytic activities. Temperature and 1-hexene concentration were the main effects found in the system. A second order effect arising from 1-hexe ne versus [AI]/[Zr] ratio was also detected. Polymer viscosity, crysta llinity and melting points decreased with 1-hexene concentration. Visc osity decreased with temperature whereas crystallinity increased when the temperature was raised from 30 to 60 degrees C.