An “OFF-to-ON” shape memory polymer conductor for early fire disaster alarming

Abstract

• Silver coated SMP conductor was fabricated by electroless deposition process. • ON-OFF switching of SMP conductor can be achieved via temperature variation. • The SMP conductor realized fast early fire alarm in fire simulation. • Thermal simulation verified the wide response range of the SMP conductor. Casualties and severe damages of environmental resources resulted from wildfires are to some extent caused by belated evacuating personnel and fighting fires. It is considered that if the timely detection of the high temperature signal can be achieved in the early stage of fire disaster, the duly rescue actions brought by the early fire alarming can extensively avoid casualty accidents and the detrimental fire spread. Therefore, in this work, we fabricate a cross-linked polycaprolactone (PCL) network, and based on its shape memory property and subsequent electroless deposition process, we prepare a smart conductor with ability of switching between non-conductive and conductive at low and high temperatures respectively. Outdoor experiments present that this electrically “OFF-to-ON” conductor can effectively respond to a fire and play a crucial role in early fire alarming under simulated fire scene. The finite element analysis simulation results further prove the advantages of this material over the traditional thermocouple in detecting temperature changes.