posted on 2024-11-06, 16:19authored byAlexander Evans, Oliver Casale, Louis J. Morris, Zoë R. Turner, Dermot O’Hare
Functional polypropylenes (FPs) are regarded as versatile
building
blocks for next-generation materials; however, their development has
been stymied due to current synthetic limitations. Here, we report
a diverse range of functionalized polypropylenes prepared via a two-step
copolymerization−postmodification strategy. Solution-phase
copolymerization of propylene and 11-bromo-1-undecene using C2, C1, and Cs-symmetric catalysts-afforded
poly(propylene)-co-(11-bromo-1-undecene), with tunable
comonomer incorporation levels, up to 15.5 mol %, with a range of
tacticities (iso-, syndio-, and atactic) and a wide molecular weight span (4−212
kg mol−1). The latent electrophilic reactivity of
the pendent bromide has been utilized in one of three general synthetic
routes, enabling the incorporation of an array of polar substituents
through the formation of a series of covalent connections (C−O,
C−N, C−S, C−P, and C−C). The resulting
FPs display distinctly altered bulk and surface properties, compared
to polypropylene: improved thermal stability and adhesion to metal,
altered wettability, and latent reactivity. This strategy allows access
to FPs with both high molecular weight and chosen tacticity, taking
advantage of well-developed metallocene catalysts and classical organic
substitution chemistry.