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A commercially viable solution process to control long-chain branching in polyethylene.
- Source :
-
Science . 3/15/2024, Vol. 383 Issue 6688, p1223-1228. 6p. 2 Color Photographs, 2 Diagrams, 1 Graph. - Publication Year :
- 2024
-
Abstract
- In polyolefins, long-chain branching is introduced through an energy-intensive, high-pressure radical process to form low-density polyethylene (LDPE). In the current work, we demonstrated a ladder-like polyethylene architecture through solution polymerization of ethylene and less than 1 mole % of a, w-dienes, using a dual-chain catalyst. The ladder-branching mechanism requires catalysts with two growing polymer chains on the same metal center, thus enchaining the diene without the requirement of a steady-state concentration of pendant vinyl groups. Molecular weight distributions lacking a high- molecular weight tail, distinctive Mark-Houwink signatures, nuclear magnetic resonance characterization, and shear and extensional rheology consistent with highly branched polyethylene architectures are described. This approach represents an industrially viable solution-polymerization process capable of producing controlled long-chain branched polyethylene with rheological properties comparable to those of LDPE or its blends with linear low-density polyethylene (LLDPE). [ABSTRACT FROM AUTHOR]
Details
- Language :
- English
- ISSN :
- 00368075
- Volume :
- 383
- Issue :
- 6688
- Database :
- Academic Search Index
- Journal :
- Science
- Publication Type :
- Academic Journal
- Accession number :
- 176029763
- Full Text :
- https://doi.org/10.1126/science.adn3067