Hydrogenation of polystyrene-b -polybutadiene-b -polystyrene mediated by group (IV) metal metallocene complexes

Abstract

Various group (IV) metal complexes, namely bis(cyclopentadienyl) titanium dichloride, bis(pentamethylcyclopentadienyl) titanium dichloride, cyclopentadienyl titanium trichloride, pentamethylcyclopentadienyl titanium trichloride, bis(cyclopentadienyl) zirconium dichloride, and bis(cyclopentadienyl) hafnium dichloride, were used as the catalysts for mediating styrene–butadiene–styrene hydrogenation. The catalytic efficiency of these catalysts was examined. The results show that catalyst activity strongly depends on the chemical structure of the metallocene complex. We also found that trialkylaluminum has a significant influence on the hydrogenation activity and thermal stability of metallocene catalysts. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 2141–2149

Styrene Moiety-Carrying Diorganozinc Compound Preparation for Polystyrene-Poly(ethylene-co-1-hexene)-Polystyrene Triblock Copolymer Production

“…The demand for SEBS is increasing rapidly owing to its advantageous weather, heat, wear, and impact resistance; adhesiveness; transparency; and recyclability. However, the high resin price represents a hurdle for market expansion. − Polymer hydrogenation is a complicated approach, requiring typically a homogeneous catalyst and consequently a tedious catalyst removal process. − SEBS is sold at approximately thrice the price of SBS. Another hurdle for market expansion is low workability; because it is produced by controlled anionic polymerization, SEBS exhibits very low dispersity ( M w / M n ) and does not flow in a melted state.…”