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oai:figshare.com:article/34022538 2026-09-29T10:05:57Z category_1 category_4 category_915 category_12 category_21 category_272 category_873 category_39 category_46 category_734 category_132 portal_63 item_type_6 month_year_09_2026

Reversible Cross-Linking of Ketone-Functionalized Polyethylenes through the Formation of Acetals Robin Lemmens (606822) Tristan De Rijck (25136475) Jules Henrotte (25136478) Rodrigo de Oliveira-Silva (10885643) Dimitrios Sakellariou (2318191) Anton Ginzburg (19927315) Dirk De Vos (7869506) Biophysics Biochemistry Physical Sciences not elsewhere classified Cell Biology Biotechnology Environmental Sciences not elsewhere classified Chemical Sciences not elsewhere classified Ecology Immunology Biological Sciences not elsewhere classified Infectious Diseases rheological characterization confirmed otf )< sub latter experiments indicate additional heating step catalyzed acetalization reaction 3 </ sub promising acid catalysts >- toluenesulfonic acid para </ removed either readily removed link density like behavior irreversible nature increased upon gel contents functionalized polyethylenes functionalized polyethylene elevated temperature catalyzed hydrolysis azeotropic distillation acetal bridges The recycling of conventional cross-linked polyethylene (XLPE) is hampered by the irreversible nature of cross-link formation. In this work, a ketone-functionalized polyethylene (kf-PE) was reversibly cross-linked through the formation of acetal bridges by using different polyol cross-linkers. The acid-catalyzed acetalization reaction was optimized using two different reaction systems in which water was removed either by azeotropic distillation or through the hydrolysis of an orthoester. <i>para</i>-Toluenesulfonic acid (pTSA) and Bi(OTf)₃ stood out as the most promising acid catalysts. Rheological characterization confirmed the thermoset-like behavior of the cross-linked materials, while solid-state NMR experiments demonstrated that the cross-link density further increased upon an additional heating step. The latter experiments indicate that the acetal cross-links are dynamic and can rearrange at elevated temperature. In this way, cross-linked materials with gel contents up to 80% were obtained. Finally, it was shown that the acetal bridges can be readily removed again through acid-catalyzed hydrolysis, which allows recycling of the original kf-PE. 2026-09-29T00:00:00Z Text Journal contribution 10.1021/acsapm.6c03134.s001 https://figshare.com/articles/journal_contribution/Reversible_Cross-Linking_of_Ketone-Functionalized_Polyethylenes_through_the_Formation_of_Acetals/34022538 CC BY-NC 4.0