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引用次数: 0
摘要
交联聚乙烯(PE)被广泛使用,但其链之间的永久性连接阻碍了回收利用。我们的研究表明,通过与二胺形成亚胺,自由基(酮基低密度聚乙烯,keto-LDPE)和催化(酮基高密度聚乙烯,keto-HDPE)非交替乙烯-CO 共聚产生的酮基官能团聚乙烯可在熔体中高效交联,从而使形成的交联聚乙烯凝胶分数高达 85%,并改善了拉伸性能。材料中的亚胺基交联可在 140 °C 下水解,从而回收高达 97% 的初始热塑性酮基聚乙烯。低酮含量(≤1.5 mol %)是保持类似聚乙烯的热性能、达到足够的交联密度和保持循环可回收性的理想选择。
Circular Cross-Linked Polyethylene Enabled by In-Chain Ketones.
Cross-linked polyethylenes (PEs) are widely employed, but the permanent links between the chains impede recycling. We show that via imine formation with diamines keto-functionalized polyethylenes from both free-radical (keto-low-density PE, keto-LDPE) and catalytic (keto-high-density PE, keto-HDPE) nonalternating ethylene-CO copolymerization can be cross-linked efficiently in the melt, resulting in gel fractions of the formed cross-linked PEs of up to 85% and improved tensile properties. The imine-based cross-links in the material can be hydrolyzed at 140 °C to recycle up to 97% of the initial thermoplastic keto-polyethylene. Low keto contents of ≤1.5 mol % are found ideal to retain PE-like thermal properties, achieve sufficient cross-link density, and maintain circular recyclability.
期刊介绍:
ACS Macro Letters publishes research in all areas of contemporary soft matter science in which macromolecules play a key role, including nanotechnology, self-assembly, supramolecular chemistry, biomaterials, energy generation and storage, and renewable/sustainable materials. Submissions to ACS Macro Letters should justify clearly the rapid disclosure of the key elements of the study. The scope of the journal includes high-impact research of broad interest in all areas of polymer science and engineering, including cross-disciplinary research that interfaces with polymer science.
With the launch of ACS Macro Letters, all Communications that were formerly published in Macromolecules and Biomacromolecules will be published as Letters in ACS Macro Letters.