Maybe. It will depend on your substrate. Joint compound could crack on a flexible surface, such as canvas. Some artists use joint compound in their work instead of Molding Paste (by Golden). Molding Paste is made with 100% acrylic polymer, while joint compound has only a little vinyl emulsion for binder. The acrylic polymer in Molding Paste helps its adhesion, flexibility, and makes it a bit smoother to use. Molding paste would be the more archival product, however many artists experiment with non-traditional materials such as this.