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Synthetic polymers can be designed to meet a particular mechanical criterion, but it is still a challenge to design a polymeric material, which simultaneously exhibits strength and ductility, and elasticity. However, natural materials show exceptional mechanical performance, modulated by composition, environmental triggers, and architecture. One lesson from nature is the combination of weak supramolecular interactions and strong covalent bonds. Understanding of materials, such as the muscle protein titin that exhibits these hierarchical elements, provides inspiration to design polymers with novel mechanics. We explored multiple strategies to develop hierarchical and functional bio-inspired materials: First part of this dissertation focuses on a self-complementary, hydrogen bonding linkage coupled with ultraviolet (UV) crosslinking to design supramolecular elastomers with tunable mechanical response. This interplay of dynamic hydrogen-bonded network and covalently crosslinked network resulted in a range of mechanical performance, controlled via the concentration of hydrogen bonding moieties and the UV curing time. Of particular note, this unique combination dramatically enhanced mechanical response of the UPy-functionalized elastomers, yielding toughness enhancement up to ~200×. In second part of this dissertation, a new class of “supramolecular interpenetrating polymer networks (Supramolecular IPNs)” was introduced where the phase-separated structure of IPNs with dynamic hydrogen-bond forming supramolecular associations and UV cross-linking sites led to materials with both increased extensibility and strength. Fascinatingly, the strong interphase region of the dissimilar networks, along with the dynamic nature of hydrogen bond-forming supramolecular associations yielded up to ~600× enhancement of mechanical toughness. In another effort, the interplay of dynamic hydrogen-bond forming supramolecular associations and phase-segregation - induced by UV crosslinking of pendent vinyl moieties - was exploited to generate vesicles and droplet-decorated vesicles on a submicron scale in model supramolecular IPNs. Of particular note is, these structures were formed in the bulk via combination of thermal activation above order-to-disorder transition (ODT) temperature of supramolecular polymer component and UV-crosslinking induced phase-segregation, without the aid of solvophobic interactions or a dewetting process on the substrate. This facile approach may serve as a platform for the design of self-assembled architectures utilizing dynamic polymeric materials.