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Positron annihilation lifetime spectroscopy (PALS) is a common technique used to characterize the porosity of polymers. Here, we expand its use to the study of ordered nanoporous polymer monoliths. Polystyrene (PS) monoliths with aligned cylindrical pores ranging in diameters from 15 to 35 nm were examined. Such large pores push the boundaries of the PALS technique. To achieve robust measurement, our system used larger detectors than those typically used for monolithic polymer samples. This was done to improve data rates while sacrificing timing resolution. Pore sizes determined using PALS were consistent with measurements made using small angle x-ray scattering. In addition, PALS was able to detect the collapse of the pores when the monolithic sample was heated above the T g of PS. Because PALS measurements are not sensitive to the nature of the order within the structure nor are they, sensitive to the open or closed nature of the pores this technique could be expanded to a variety of other sample types.

Developments in micro and nanotechnology within the renewable energy industry have the potential to create significant advances for the renewable energy industry. A review of selected renewable energy sectors being influenced by micro and nanotechnology was performed, finding that the most promising areas involve electricity generation, biomass technologies, and hydrogen technologies. Such technologies include: surface microtexturization and nanocrystalline films in photovoltaic and photoelectrochemical cells; nanoscale catalysts and membranes in biomass or thermochemical hydrogen generation; surface utilization of carbon nanotubes in hydrogen storage and fuel cell applications. These advances may increase process yields and efficiencies, and also may lower overall costs.

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Hydrogels are 'intelligent' polymers that respond to various stimuli by swelling or deswelling their volume through the intake or expulsion of solvent. This, sometimes enormous, volume transition can be harvested for purposes such as, artificial muscles, actuating components of microfluidic systems, or drug delivery. Recently an increased number of numerical models have been employed to simulate this volume transition, in hopes of bypassing high prototyping and optimization costs. This work presents a coupled multiphysics chemo-electro-mechanical model for the simulation of hydrogels subjected to chemical and electrical stimulation, performed using the commercial finite element analysis software COMSOL Multiphysics 3.3. Numerical results include the local transient response of the electrical potential, mobile ion concentrations, and hydrogel displacement with associated osmotic pressure. In addition, a comparison is made between this model and literature employing Donnan theory. This work also extends the multiphysics model to examine the effect of lowering the hydrogel's relative permittivity, increasing the magnitude of the electrical potential, and reversing the stimulating electrical field. The numerical models for both chemical and electrical stimulation were in agreement with literature.