This research project will expand a recently discovered class of hybrid membrane materials created via vapor phase infiltration (VPI), a gas-phase process that infuses polymers with inorganic constituents intermixed at the atomic level. These hybrid membranes show dramatically enhanced stability in organic solvents while retaining salient membrane properties of high permeance and discerning selectivity. Because the design space for such membranes - including polymer chemistry, inorganic chemistry, and hybrid microstructure - is enormous, traditional Edisonian-based materials development methods are impractical. To address this challenge, the research team combines expertise in: (1) phenomenological theory of VPI materials synthesis, (2) membrane and separation science, (3) materials simulations and data-driven design, and (4) advanced statistical algorithms that incorporate known phenomenological physics with limited initial data. Efforts in each of these areas will rapidly steer the search towards chemical, morphological, and processing spaces of opportunity. Specifically, this project will focus on the design of materials synthesis processes for targeted membrane chemistries and microstructures. The outcomes of this research will be (1) the creation of tangible hybrid membranes based on polymers of intrinsic micro-porosity with superior performance and stability, (2) the identification of key physiochemical descriptors for controlling structure and performance in these hybrid membranes, and (3) the development of new strategies for handling data sparsity and physical phenomena integration into materials informatics-based design.