Work

Switching the shape of crosslinked high-density polyethylene using α-relaxation

Year: 2025

Type: article

Abstract: Thermally triggerable shape memory polymers (SMPs) typically exploit the glass transition (Tg) or melting temperature (Tm) as switching mechanisms. Recent work on crosslinked low-density polyethylene (xLDPE) indicated that the α-relaxation of semi-crystalline thermoplastics can also act as a switch. However, since the α-relaxation of xLDPE partially overlaps with its melting range, the contribution of crystal melting could not be ruled out. To clarify this, the present study investigates crosslinked high-density polyethylene (xHDPE), whose α-relaxation temperature (Tα) is well separated from the onset of melting. The results demonstrate that reversible switching between temporary and intermediate shapes occurs exclusively above Tα and below Tm, confirming that α-relaxation alone drives shape recovery without any melting. This establishes α-relaxation as a genuine switching mechanism in semi-crystalline SMPs and opens up new possibilities for the design of multi-shape memory materials.

Source: Polymer

DOI: 10.1016/j.polymer.2025.129287

Authors: Michail Maricanov, Robert David Ludwig Jerusalem, Charlotte Meykranz, Lukas Schultz, Joerg Christian Tiller, Frank Katzenberg

Institution: TU Dortmund University

Language: English

Topic: Polymer composites and self-healing

Subfield: Polymers and Plastics

Field: Materials Science

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $3,980

Funder: Deutsche Forschungsgemeinschaft