# Synthesis of Cleavable Polyolefins via Ring-Opening Insertion Metathesis Polymerization (ROIMP) of Cyclopentene with Unsaturated Polyester Oligomers

## TL;DR

Scientists developed a new way to make environmentally friendly plastics that can be broken down easily using a chemical process called ROIMP.

## Contribution

A novel method for synthesizing cleavable polyolefins via ROIMP using cyclopentene and unsaturated polyester oligomers.

## Key findings

- Cleavable polyolefins were successfully synthesized using ROIMP with cyclopentene and polyester/polycarbonate oligomers.
- Hydrolysis of the resulting polymers produced OH-functionalized oligomers suitable for further hydrogenation.
- The approach was demonstrated at scale using oligo-diallyl succinate.

## Abstract

The replacement of
persistent plastics with chemically recyclable
and environmentally benign alternatives is an urgent environmental
challenge. Although an increasing number of degradable polymers are
now available, many face limitations that prevent their efficient
direct substitution for durable plastics, such as polyethylene. Here,
we present a methodology for the synthesis of polyolefin copolymers
containing cleavable units via Ring-Opening Insertion Metathesis Polymerization
(ROIMP) of cyclopentene (CP) with unsaturated polyester
and polycarbonate oligomers. In the first step, diallyl ester oligomers
were prepared through acyclic diene metathesis (ADMET) polymerization
followed by copolymerization with CP via ROIMP to yield
long-chain polypentenamer (PPe) dyads separated by singular,
easily cleavable ester or carbonate functionalities. Hydrolysis of
the resulting cleavable PPe elastomers produced low-molecular-weight,
telechelic OH-end-functionalized PPe oligomers. Subsequent
hydrogenation using Wilkinson’s catalyst afforded saturated
long-chain hydrocarbon polymers with randomly distributed cleavable
subunits. The scalability of this approach was demonstrated for the
ROIMP of CP with oligo-diallyl succinate (oligo-DAS).