The concept of micellar catalysis was transferred to the hydroaminomethylation of 1‐octene with N,N‐dimethylamine. In the first series of experiments a rhodium(I) complex with amphiphilic triphenylphosphane functionalized poly(2‐oxazoline)s as macroligand was applied as catalyst. Results obtained under standard hydroformylation conditions (T = 100 °C, p = 50 bar) were not satisfying with regard to activities and selectivities of the hydroaminomethylation reaction. Rising the temperature to 150 °C increased the yield of amine to 22% with a corresponding n/iso selectivity of 7.5 and a TOF number of 461 h−1. Best results were obtained by applying a dual Rh/Ir catalyst within the polymeric micelles leading at lower temperature of 130 °C to an amine yield of 24% with a corresponding n/iso selectivity of 11 and TOF numbers of about 600 h−1.magnified image
Styrene was isospecifically polymerized on dichloro [1,4-dithiabutandiyl-2,2′-bis(6-tert-butyl-4methylphenoxy)]titanium (1) activated with methylaluminoxane in the presence of monoolefins such as 1-hexene, cyclopentene, and norbornene and nonconjugated diolefins such as 1,9-decadiene, 1,7-octadiene, and dicyclopentadiene. The molecular weight of isotactic polystyrene was varied from 2000 to 600 000 g/mol as a function of the olefin/styrene molar ratio without sacrificing high catalyst activities. Chain transfer constants were determined, with the highest values found for linear mono-and nonconjugated diolefins. In contrast to norbornene, 1-olefin incorporation was very low. End groups were identified by means of 13 C NMR investigations of polymers containing 13 C-labeled 1-octene. Olefin-and diolefin-terminated isotactic polystyrenes including novel vinyl-terminated macromonomers were obtained in high yields.
Vinyl‐terminated isotactic polystyrene macromonomers were copolymerized with ethylene and 1‐octene to new polyolefin graft copolymers with crystallizable polystyrene side chains. The iPS content was varied from 4 to 78 wt.‐% using different metallocene and halfsandwich catalysts. No solubility problems of the stereoregular macromonomer occured, because iPS does not crystallize during polymerization. In addition the polymers show nanophase separation of the polyolefin backbone and the iPS side chains. The crystallization of iPS, having a melting point of about 200 °C, can be achieved by annealing. This synthesis strategy allows the fabrication of a new class of thermoplastic elastomers with improved heat distortion temperatures.magnified image
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