This study presents a novel biobased polyurethane (PU) adhesive with integrated performance characteristics: mechanical robustness, high adhesion strength, intrinsic fire retardancy, switchable adhesion, and degradability. The adhesive is designed using a fire-retardant phosphorus-containing pimaric acid derivative, AD, as a functional segment. The PU adhesive exhibits an ultrahigh adhesion force of 38.8 N cm⁻¹ on a polyvinyl chloride (PVC) substrate. It can be reused due to its solubility in ethanol and shows temperature-responsive switchable adhesion without degradation. The adhesive also demonstrates intrinsic fire retardancy due to its biphasic modes of action. The labile ester bonds in the structure enable complete degradation in the presence of lipase or dilute acid. The adhesive is also shown to have superior heat dissipation efficiency compared to commercial heat sinks when blended with copper powders. The study highlights the potential of this adhesive for next-generation sustainable, high-performance adhesives with functional integration and circular life cycles, suitable for applications in electronics, furniture, construction, and automotive industries. The adhesive's unique properties, including its ability to self-extinguish upon flame removal and its dual-mode degradability, make it a promising candidate for sustainable and environmentally friendly applications. The study also addresses the challenges of creating mechanically robust, fire-retardant PU adhesives and offers a novel design approach for sustainable adhesives.This study presents a novel biobased polyurethane (PU) adhesive with integrated performance characteristics: mechanical robustness, high adhesion strength, intrinsic fire retardancy, switchable adhesion, and degradability. The adhesive is designed using a fire-retardant phosphorus-containing pimaric acid derivative, AD, as a functional segment. The PU adhesive exhibits an ultrahigh adhesion force of 38.8 N cm⁻¹ on a polyvinyl chloride (PVC) substrate. It can be reused due to its solubility in ethanol and shows temperature-responsive switchable adhesion without degradation. The adhesive also demonstrates intrinsic fire retardancy due to its biphasic modes of action. The labile ester bonds in the structure enable complete degradation in the presence of lipase or dilute acid. The adhesive is also shown to have superior heat dissipation efficiency compared to commercial heat sinks when blended with copper powders. The study highlights the potential of this adhesive for next-generation sustainable, high-performance adhesives with functional integration and circular life cycles, suitable for applications in electronics, furniture, construction, and automotive industries. The adhesive's unique properties, including its ability to self-extinguish upon flame removal and its dual-mode degradability, make it a promising candidate for sustainable and environmentally friendly applications. The study also addresses the challenges of creating mechanically robust, fire-retardant PU adhesives and offers a novel design approach for sustainable adhesives.