Polymorphic Behavior and Mechanical Properties of Isotactic 1-Butene–Ethylene Copolymers from Metallocene Catalysts

• DOI: 10.1021/ma500088a
• Publication Date: 2014-06-17T15:02:27Z
• Authors: Claudio De Rosa; Odda Ruiz de Ball...; Finizia Auriemma; Rocco Di Girolamo; Carmela Scarica; Giovangiuseppe Gi...; Simona Esposito; Simona Guidotti; Isabella Camurati
• Keywords: Tacticity; Butene; Post-metallocene catalyst; Polybutene; Ethylene propylene rubber; Thermoplastic elastomer

A study of the crystallization behavior and mechanical properties random isotactic butene–ethylene copolymers prepared with a metallocene catalyst is presented. The use catalysis ensures fine control over molecular structure low concentration rr stereodefects (0.8%), negligible amount regiodefects, uniform distribution ethylene constitutional defects. This characteristic has allowed evidencing only effect presence units on polymorphic polybutene (iPB). accelerates transition form II into I at room temperature nearly 6 mol % favors direct from melt stable I. also affects iPB produces increase flexibility ductility increasing content. significant modification observed for higher than 8 %, development elastomeric properties, never homopolymer Ziegler–Natta catalysts not in similar content stereo In these samples, are due to degree crystallinity that develops upon aging by I′ amorphous phase.