Two independent sets of studies are conducted on two collections of thermoset coatings, each exploring the molecular-level structures of its subject materials. The first work searches for the sources of durability in a library of paint film samples, prepared using linseed oil and inorganic pigments 1-2 decades before analysis. The second inquiry examines a series of end-linked polymer networks, created using different monomer architectures through molecular dynamics. Investigations proceed by drawing connections between the materials’ local structures and their large-scale properties: for oil paint, guided by questions of whether metal carboxylates are responsible for the films’ cohesion, and if so, then through what means; for simulations, by viewing all data through the lens of the theory of rubber elasticity, as well as outside of it. In the end, a new working model for the structure of mature oil paint is proposed; extensive connections between model and real-world polymers are made.