Plastics offer several advantages, but their production
and disposal
processes have severe environmental implications. To overcome these
issues, there is a need to switch from the linear to a circular economy
by recycling plastic waste and by utilizing renewable resources to
create bioplastics. However, this is challenging in the case of nonbiodegradable
polyolefins (POs), which form the largest fraction of produced polymers
and the least recycled one. Mechanical recycling, chemical recycling,
and PO bioplastics are the three pillars of PO circular economy. Although
mechanical recycling is an environmentally and economically viable
option, it often results in the degradation and downgrading of POs.
Nonetheless, innovations in mechanical recycling, such as the use
of (nano)fillers or compatibilization with olefin block copolymers,
attempt to mitigate these issues. Furthermore, the development of
covalent adaptable networks improves the mechanical properties of
recycled PO thermoplastics and provides recyclable PO elastomers.
If mechanical recycling fails to meet the desired characteristics
of the recyclate PO, chemical recycling to other chemicals is a potential
alternative. Although retrieving the monomer is ideal for achieving
a closed-loop circular economy, traditional approaches for the noncatalytic
chemical recycling of POs are energy-intensive and lack specificity.
This has been tried to be addressed by advancements in catalytic approaches.
Finally, biobased polyolefins, especially those produced through emerging
nonbiochemical approaches, offer attractive alternatives that can
be integrated into existing petrochemical plants. With this comprehensive
perspective on POs circular economy academic and industrial researchers
of the field can better contribute to a more sustainable future.