Shape memory effect for recovering surface damages on polymer substrates

Abstract Self-repair properties based on shape-memory features of covalently crosslinked semi-crystalline polyalkenamers were demonstrated by thermal-activated recovery of performed surface marks (indented holes and scratches). Shape memory polymers were prepared by mixing a commercial polycycloocte...
Ausführliche Beschreibung

Abstract Self-repair properties based on shape-memory features of covalently crosslinked semi-crystalline polyalkenamers were demonstrated by thermal-activated recovery of performed surface marks (indented holes and scratches). Shape memory polymers were prepared by mixing a commercial polycyclooctene (PCO) with different percentages of peroxide, and then these mixtures were processed by compression moulding to obtain crosslinked sheets. With the aid of a hardness test pencil, holes and scratches in the surface of the materials were realized with different known forces (5, 10 and 15 N). The disappearance of surface defects was evaluated using both optical and contact surface profilometry, as well as optical microscopy under heating processes. This technique allowed evaluating shape recovery ratios of edgewise holes in PCO samples. In parallel, the analysis of maximum depth of indentations with temperature for edgewise samples by optical microscopy allows evaluating shape recovery. As a complementary tool for analysing thermal shape-recovery and surface resistance to indentation, thermal properties and hardness were investigated by DSC and Shore durometer test, respectively. Ausführliche Beschreibung