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Depolymerizable Olefinic Polymers Based on Fused-Ring Cyclooctene Monomers
Published on: December 16, 2022
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Waxes from Long-Chain Aliphatic Difunctional Monomers
Marcel Eck1, Celia Stoltze1, Stefan Mecking1
1Department of Chemistry, University of Konstanz, Universitätsstr. 10, 78457 Konstanz, Germany.
ACS Sustainable Chemistry & Engineering
|December 1, 2023
Summary
New biodegradable linear ester waxes (WLE) offer eco-friendly alternatives to petrochemical polyethylene waxes. These waxes, synthesized via polycondensation and chain scission, exhibit tunable properties and a promising environmental profile.
Area of Science:
- Polymer Chemistry
- Materials Science
- Green Chemistry
Background:
- Petrochemical polyethylene waxes are vital industrial additives but raise environmental concerns due to poor biodegradability.
- Developing biodegradable alternatives is crucial for sustainable manufacturing and reducing environmental impact.
Purpose of the Study:
- To synthesize and characterize novel biodegradable linear ester waxes (WLE) as sustainable alternatives to conventional polyethylene waxes.
- To investigate the influence of molecular structure and end-group functionality on the properties of these novel waxes.
Main Methods:
- Utilized bottom-up (nonstoichiometric polycondensation) and top-down (chain scission) synthesis approaches.
- Created linear ester repeat unit motifs (WLE-12,12 and WLE-2,18) with varying carbon chain lengths.
- Analyzed molecular weight, thermal properties (melting point), crystalline structure, and rheological behavior.
Main Results:
- Successfully synthesized WLEs with molar masses ranging from 600-10,000 g/mol.
- Demonstrated that end-group functionality (methyl ester, hydroxy, carboxylic acid) significantly affects thermal properties, with carboxylic acid end groups yielding higher melting points.
- Achieved HDPE-like orthorhombic crystalline structure and comparable rheological properties to commercial polyethylene waxes.
Conclusions:
- WLE-12,12 and WLE-2,18 waxes are viable, biodegradable, and potentially biosourced alternatives to conventional petrochemical polyethylene waxes.
- The developed synthesis methods allow for tunable properties, making these waxes suitable for diverse applications.
- These findings contribute to the development of more sustainable materials in the chemical industry.
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