Nanoporous membranes based on self‐assembled block polymer precursors are an emerging class of promising separation, purification, and sensing devices due to the ability of researchers to control the nanostructure and chemistry of these multifunctional materials and devices. In fact, modern polymer chemistry provides techniques for the facile, controlled synthesis of the block polymers that constitute these devices. These designer macromolecules, in turn, can then self‐assemble into functional nanostructures depending upon the chemical identity of the synthesized block polymers and the thin film fabrication methods employed. After fabrication, these nanoporous membranes offer a highly tunable platform for applications that require high throughput, high surface area, homogeneous pore size, and varying material properties. And, with these readily tunable chemical and structural properties, block polymer membranes will allow for significant improvements in myriad applications. In this Review, we summarize the key advances, with a specific emphasis on the previous 5 years of work, that have allowed block polymer‐based membranes to reach their current level of technology. Furthermore, we project how these state‐of‐art, self‐assembled block polymer membrane technologies can be utilized in present‐day and future application arenas. In this way, we aim to demonstrate that the rigorous work performed on block polymer‐based membranes has laid a strong foundation that will allow these macromolecular systems to: (1) be major avenues of fundamental scientific research and (2) be parlayed into transferable technologies for the betterment of society in the imminent future. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41683.

The cationic copolymerization of tung oil, limonene, and myrcene as comonomers, initiated by boron trifluoride, is presented and discussed in this work. Dynamic mechanical analysis revealed that all copolymers behave as thermosets. FTIR spectra for both copolymers, after extraction with dichloromethane, suggested that the major component of the insoluble fraction was reacted tung oil (a cross‐linked triglyceride network). Likewise, unreacted tung oil was found to be the main component of the soluble phase. Also, all the copolymers showed only one tan δ peak, indicating no phase separation. Glass transition temperature (Tg) increased with the myrcene content and decreased almost linearly as the limonene content increased. Furthermore, the Fox and Loshaek model showed a relatively good prediction of the Tg values of the polymers. The Young's modulus ranged from 33.8 to 4.7 MPa for all tested thermosets. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 41155.

Rotational and oscillatory shear rheometry were used to quantify the flow behavior under minimal and significant solvent evaporation conditions for polymer solutions used to fabricate isoporous asymmetric membranes by the self-assembly and non-solvent induced phase separation (SNIPS) method. Three different A-B-C triblock terpolymer chemistries of similar molar mass were evaluated: polyisoprene-b-polystyrene-b-poly(4-vinylpyridine) (ISV); polyisoprene-b-polystyrene-b-poly(N,N-dimethylacrylamide) (ISD); and polyisoprene-bpolystyrene-b-poly(tert-butyl methacrylate) (ISB). Solvent evaporation resulted in the formation of a viscoelastic film typical of asymmetric membranes. Solution viscosity and film viscoelasticity were strongly dependent on the chemical structure of the triblock terpolymer molecules. A hierarchical magnitude (ISV>ISB>ISD) was observed for both properties, with ISV solutions displaying the greatest solution viscosity, fastest film strength development, and greatest strength magnitude.

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Self‐assembled block polymer membranes are rising to the fore of next‐generation separations technologies, and a particular fabrication process of significant interest is the self‐assembly and non‐solvent induced phase‐separation (SNIPS) method. This is because the SNIPS process allows for the facile manipulation of independent variables to produce simultaneously size‐ and chemically‐selective membranes in a scalable manner. Despite significant advances in the SNIPS membrane fabrication procedure, the early‐stage solution behavior of many of the polymer–solvent systems employed is still poorly understood. This work addresses the challenges posed by these systems and illuminates guiding relationships for the optimization of SNIPS membrane casting solutions. Specifically, polymer aggregate structures and critical micelle concentration (CMC) values are determined for an A‐B‐C triblock polymer dissolved in 1,4‐dioxane using a combination of scattering and atomic force microscopy techniques. The CMC of this system ranges from 20 to 80 μM and shows a strong dependence on the polymer composition and solution processing method. Additionally, the shape of the self‐assembled structures in solution can be altered by varying these parameters. These studies establish the relationships between polymer solution properties (i.e., the block polymer composition and the processing method) and assembly behavior as they impact membrane fabrication through SNIPS processing. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45531.