Catalyst Type Effects on Structure/Property Relations of Polypropylene Random Copolymers
نویسندگان
چکیده
Polypropylene (PP) random copolymers are an important class of commercial materials that can be tuned for a wide range different applications. The structure–property relations mainly discussed in this article focusing on two major influencing factors, the catalyst system and type amount comonomer. Ziegler–Natta (ZN) systems still dominate production polypropylene todays sixth-generation ZN catalysts based postphthalate donor systems. Metallocene (MC) offer possibilities to exactly control microstructure polymer even better. Mostly, ethylene is used as comonomer being randomly distributed up 7.3 mol% when using catalysts. For single site catalysts, homogenous (single phase) achieved contents 20.8 mol%. incorporated reduces crystallization speed lamellar thickness thus affording soft highly transparent materials. Random terpolymers with higher ?-olefins only play minor role but additional possibility property adjustments. PP also varied their performance through multistage polymerizations, altering content or molecular weight polymerization reactors.
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ژورنال
عنوان ژورنال: Macromolecular Chemistry and Physics
سال: 2021
ISSN: ['1521-3935', '1022-1352']
DOI: https://doi.org/10.1002/macp.202100302