HYDROGENATED BUTADIENE ETHENE/1-OLEFIN TERPOLYMERS AS MODEL SUBSTANCES FOR SHORT-CHAIN BRANCHED POLYETHYLENE/

butadiene-alt-ethene)-co-(butadiene-alt-1-olefin)] terpolymers were sy nthesized by Ziegler-Natta polymerization using VO(O-neopentyl)(2)Cl/A l(i-Bu)(3) catalyst system in toluene. Variation of the 1-olefin/ethen e ratio in the monomer feed produces terpolymers with mixed units of b utadiene-alt-ethene and butadiene-alt-1-olefin. After hydrogenation on e obtains model substances for LLDPE with a special distribution of me thylene sequences between branching points. Differential scanning calo rimetry (DSC) was used to determine the degree of crystallinity and th e melting behavior. From the melting temperature region, the thickness distribution of the crystal lamellae, and thus the average number of C-atoms between the alkyl branches, can be determined. From detailed X -ray diffractometry, the mean crystallite size, the lattice distortion s and the degree of crystallinity was determined for those products wh ich show distinct reflections. The crystallization behavior can only b e described by a three-phase model.