  Electronics are integral to modern life; however, at their end-of-life these
devices produce environmentally hazardous electronic waste (e-waste). Recycling
the ubiquitous printed circuit boards (PCBs) that make up a substantial mass
and volume fraction of e-waste is challenging due to their use of irreversibly
cured thermoset epoxies. We present a PCB formulation using transesterification
vitrimers (vPCBs), and an end-to-end fabrication process compatible with
standard manufacturing ecosystems. We create functional prototypes of IoT
devices transmitting 2.4 GHz radio signals on vPCBs with electrical and
mechanical properties meeting industry standards. Fractures and holes in vPCBs
can be repaired while retaining comparable performance over more than four
repair cycles. We further demonstrate non-destructive decomposition of
transesterification vitrimer composites with solid inclusions and metal
attachments by polymer swelling with small molecule solvents. We hypothesize
that unlike traditional solvolysis recycling, swelling does not degrade the
materials. Through dynamic mechanical analysis we find negligible catalyst
loss, minimal changes in storage modulus, and equivalent polymer backbone
composition across multiple recycling cycles. We achieve 98% polymer recovery,
100% fiber recovery, and 91% solvent recovery which we reuse to create new
vPCBs without degraded performance. Our cradle-to-cradle life-cycle assessment
shows substantial environmental impact reduction over conventional PCBs in 11
categories.
