filled-epoxy resin
An epoxy resin with some kind of material mixed in to thicken it, bulk it out. By making it thicker, less resin is used made to be more controlable. Filled-epoxy resin has high-viscosity and less shrinkage because there is less liquid to evaporate. Resin with ground gypsum can be used in high heat areas, like attics because it ups the heat resistance. Very high heat will soften resin, making it easy to remove. Some other fillers include: dirt, sawdust, phenolic or glass microballoon (ziospheres,) chopped cotton, graphite to give it more paste or putty-like consistent. By filling epoxy resins, they are made to be thixatropic, meaning it creates internal strength and weight is enough that it can stand up straight and can overcome the effects of gravity. (Preservation Science, 2019)