Efficient synthesis of thermoplastic elastomeric amorphous ultra-high molecular weight atactic polypropylene (UHMWaPP)

Abstract

The synthesis of amorphous ultra-high molecular weight atactic polypropylene (UHMWaPP), with molecular weights (Mw) up to 2.0 MDa and narrow polydispersities is reported using remarkably efficient permethylindenyl-phenoxy (PHENI*) titanium complexes.

Fully tuneable ethylene–propylene elastomers using a supported permethylindenyl-phenoxy (PHENI*) catalyst

“…The sMAO-supported PHENI* complex sMAO-Me2 SB-( t Bu2 ArO,I*)TiCl 2 ([Al sMAO ] 0 /[Ti] 0 = 200; 1) was prepared, 21,22 and utilised in slurry-phase olefin copolymerisations. Polymerisations were carried out within a temperature of polymerisation (T p ) range of 30 r T p r 90 1C under 2 bar total pressure with 10 mg of 1 (B712 nmol Ti) and either MAO or TIBA as cocatalyst ([Al] 0 /[Ti] 0 = 1000) in 50 mL hexanes as a diluent.…”

“…In these cases the amorphous nature of the aPP segments is responsible for the degraded behaviour, while the M w is insufficient to achieve the desirable elastic properties of UHMWaPP. 22 Following the successful synthesis of EPM polymers at high activity and with tuneable composition, 1/TIBA was used in the terpolymerisation of ethylene, propylene, and 5-ethylidene-2norbornene (ENB). As well as being easier to handle than butadiene, ENB is commonly used as a diene in multicomponent polymerisations.…”

“…Even in this case, a clear preference for ethylene is observed with 13% incorporated from a 3 : 97 E : P feed. 10 Following our recent report of group four permethylindenylphenoxy (PHENI*) catalysts, and their outstanding performance for ethylene and propylene homopolymerisation, 21,22 we now describe the application of the PHENI* complex Me2 SB( t…”

“…Following our recent report of group four permethylindenyl-phenoxy (PHENI*) catalysts, and their outstanding performance for ethylene and propylene homopolymerisation, 21,22 we now describe the application of the PHENI* complex Me 2 SB( t Bu 2 ArO,I*)TiCl 2 ({(η 5 -C 9 Me 6 )Me 2 Si(2,4- t Bu 2 -C 6 H 2 O)}TiCl 2 ), heterogenised on solid polymethylaluminoxane (sMAO), 23 1 (Fig. 1), for the production of EPM elastomers.…”

“…In these cases the amorphous nature of the a PP segments is responsible for the degraded behaviour, while the M w is insufficient to achieve the desirable elastic properties of UHMWaPP. 22…”