An initial investigation into active disassembly using shape memory polymers

Abstract

The aim of the work was to demonstrate an alternative to conventional end-of-life (EOL) disassembly strategies such as robotic or hand dismantling. This initial investigation reports the disassembly of consumer electronic products using smart materials in the design of embedded releasable fasteners. A series of products was tested in a variety of different ways using shape memory polymers (SMPs). Tests were run on macroassemblies and subassemblies of telecommunications goods. The devices designed with SMP used two distinct properties of the material suited to active disassembly: the mechanical property loss (MPL), in this case a loss of rigidity in the thread of the SMP screws; the shape memory effect (SME), a change in form, resulting in this case in the loss of moulded thread from SMP shape memory effect screws. Once SMP components were developed and embedded into the candidate products, timed disassembly experiments were conducted. These tests used infrared, air jet and water bath methods for applying heat to trigger the SMP devices. Once the trigger temperature was reached, shape change and property loss occurred in the screws and brackets, allowing assembly release.