Model hexyl-branched linear low density polyethylene (C8-LLDPE) samples were synthesized by the ring-opening metathesis copolymerization (ROMP) of the 5-hexylcyclooct-1-ene (1) and cyclooctadiene (COD), followed by catalytic hydrogenation. The ROMP of 1 and copolymerization of 1 and COD using the Grubbs second generation catalyst (G2) afford polymers with the number of hexyl branches based on the feed composition. The resulting hexyl-branched polymers, poly(1) and poly(1-stat-COD), were completely converted into model C8-LLDPE samples by catalytic hydrogenation. The C8-LLDPE samples exhibit the expected reduction in density on branching content. The melting temperature (T m), crystallization temperature (Tc), and heat of fusion/crystallization (ΔHm/ΔHc) of these materials were studied by differential scanning calorimetry.
Bibliographical noteFunding Information:
This work was supported by The Dow Chemical Co. and the Abu Dhabi-Minnesota Institute for Research Excellence (ADMIRE); a partnership between the Petroleum Institute (PI) of Abu Dhabi and the Department of Chemical Engineering and Materials Science of the University of Minnesota.