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A highly improved strategy is established in order to systematically integrate excess exfoliated graphene oxide (GO) as fillers into polyacrylonitrile (PAN) nanofibers via electrospinning. Simple modification of GO surface allowed for their loading efficiency into the nanofibers to surpass the typical limits. Among many features, the hydrophilic and mechanical properties of these membranes were found to be significantly increased compared to the original PAN and bare GO-loaded membranes probably due to the effective reinforcing filler effect caused by the even distribution of the modified GO within the PAN nanofibers. Thus, the simple surface modification of fillers can facilitate the capability of controlling the loading efficiency into electrospun nanofibers which can highly impact the quality and performance of final composite membranes.

High performance, full color electrophotographic printers are gaining acceptance in many office environments. In this study, the authors controlled the aggregation of three different colloidal dispersions using four different multivalent metallic coagulants over a wide pH range to develop a polyester-based chemically prepared toner (CPT). An operational limit existed for the total quantity of each metallic coagulant required to achieve a narrow particle size distribution at a mean target aggregate size. This, when exceeded, produced a viscous, inoperative sludge in the reactor. The optimal pH condition for each coagulant system was mainly dependent on the electrostatic balance produced by deprotonation of exposed carboxylic acid groups on the polyester resin particles at a pHbetween 5.5 and 6.5. Additional electrostatic interactions between the polyester colloidal dispersions and the monovalent cations (M1+) in the metallic coagulation system at high electrolyte concentrations created a favorable environment to reproduce core-toner particles with a narrow particle distribution at a mean target size. By manipulating the aggregation process, the individual nano-dispersions coalesced in an aqueous environment to form a polyester-resin-based chemical toner that was uniform in particle size and had low total volatile organic compound (VOC) leveL The printing and image performance of this toner using a color laser printing system was also observed. This final polyester toner was optimized for high speed, energy efficient electrophotographic printers that utilize an oil-free fusing subsystem that operates at a low fusing temperature. The image quality and toner usage of these toners meet the specifications of major printer manufacturers for digital printing technologies. ©2013 Society for Imaging Science and Technology. [ABSTRACT FROM AUTHOR]