Dimethyl isosorbide (DMI)a well-known biobased high boiling green solventwas used for the first time in the preparation of poly­(vinylidene fluoride)- and poly­(ether sulfone)-based membranes. Preliminary thermodynamic (Hansen and Hildebrand solubility parameters, relative energy difference) and kinetic (viscosity) studies on DMI confirmed that this solvent possesses the required physical/chemical properties to be exploited in casting membranes. Membranes were prepared by nonsolvent induced phase separation (NIPS) and a combination of vapor induced phase separation (VIPS)-NIPS techniques varying the exposure time to humidity. This latter approach led to the formation of membranes with a porous architecture avoiding the use of any pore forming additive. The so-prepared membranes were, then, fully characterized in terms of morphology, polymorphism (in case of PVDF), wettability, thickness, porosity, pore size, and water permeability. The membranes revealed different structures and a tunable pore size in the range of ultrafiltration (UF) and microfiltration (MF) that render them ideal for applications in water treatment processes.

Physico-chemical and sensory techniques enabled the identification of bioadhesive hydrogel formulations with positive characteristics for cosmetic applications. Formulations which combined carbomer homopolymer type C with xanthan gum or with carbomer copolymer type B were the most promising for bioadhesive skin products. Caffeine release profiles of selected formulations were not statistically different. Both hydrogels gradually released the active ingredient, reaching approximately 80% within the first 5 h, and their profiles were well described by the Higuchi model. In this context, it could be concluded that the selected hydrogels are suitable bioadhesive hydrogel formulations for cosmetic application on the skin.

The present investigation reports as it is possible to prepared polyvinylidene fluoride (PVDF) membranes for microfiltration (MF) and ultrafiltration (UF) applications, by using triethyl phosphate (TEP) as non–toxic solvent in accordance with the Green Chemistry. Casting solutions containing different concentrations of polyethylene glycol (PEG) were prepared in order to study its effect on the final membrane morphology and properties. The possibility to finely modulate membrane properties was also investigated by applying two different membrane preparation techniques, the Non-Solvent Induced Phase Separation (NIPS) and its coupling with Vapour Induced Phase Separation (VIPS). Membranes’ morphology was detected by Scanning Electron Microscopy (SEM). Thickness, porosity, contact angle, pore size and water permeability were also recorded. Both the PEG content in the dope solution and the selected time intervals during which the nascent films were exposed to established relative humidity and temperature were found to play a crucial role in membrane formation. In particular, it was demonstrated as, by varying PEG content between 10 and 20 wt %, and by setting the exposure time to humidity at 0/2.5/5/7.5 min, membranes with different pore diameter and bicontinuous structure, suitable for UF and MF applications, could be easily obtained.

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