Should electrolytic or polypropylene capacitor be used in buck converter?

It's obvious that for same capacitance value electrolytic is way much
cheaper, and its higher ESR produces a ESR zero at lower frequency
which is beneficial to design of controller since type II compensator
can be used. However since my design works at 55kHz, I'm just not sure
if electrolytic is a good performer at such high frequency, or if I
should go for a polypropylene one.

Besides, polypropylene has lower ESR, so does that mean it can handle
much larger ripple current since the power dissipation is lower? Is
there limitation on max ripple current that polypropylene cap can
accept, since I couldn't find this parameter in most datasheets?

Thanks for any advice.

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