Thermal stabilisation of squaraine dyes by encapsulation in a rotaxane

Here we show how encapsulation of a squaraine dye in a rotaxane structure renders the dye that normally start decomposing at 100 °C stable above 250 °C. This thermal stabilisation makes new applications possible, and we demonstrate how the squaraine rotaxane can mediate laser welding of polyethylene, a process that requires thermal stability.