monolithic aerogels of high molecular weight polyethylene (mw= 3x106- 6x106 g/mol) have been prepared by solvent extraction with supercritical carbon dioxide from thermoreversible gels prepared in decalin. these low density and highly porous aerogels present an apparent porosity up to 90%. the aerogel morphology observed by scanning electron microscopy (sem) is characterized by spherulitic stru...

Monolithic aerogels of high molecular weight polyethylene (Mw= 3x106- 6x106 g/mol) have been prepared by solvent extraction with supercritical carbon dioxide from thermoreversible gels prepared in decalin. These low density and highly porous aerogels present an apparent porosity up to 90%. The aerogel morphology observed by scanning electron microscopy (SEM) is characterized by spherulitic stru...

Almost 40% of active Pharmaceutical ingredients have low oral bioavailability, high hepatic first-pass metabolism and also less efficient in crossing the blood brain barrier for brain targeting through oral delivery. To overcome this problem the various system such as: nasal spray, gels, emulsions, droplets, suspensions, powders and thermoreversible mucoadhesive gels etc have been studied for n...

Gelation of tannin-formaldehyde (TF) solutions was systematically investigated by changing pH and concentration of TF resin in water. In this way we constructed the TF phase diagram, from which chemical hydrogels could be described, and also synthesized thermoreversible tannin-based hydrogels. Conditions of non-gelation were also determined. Hydrogels were dried in supercritical CO2, leading to...

Mn3O4 aerogels and their graphene nanosheet (GN) composite aerogels were synthesized by a simple supercritical-ethanol process. In the process, supercritical ethanol acted as a reductant to reduce graphene oxide and MnO2 gels simultaneously. The synthesized aerogels consisted of 10-20 nm Mn3O4 nanocrystallites, with BET-specific surface areas around 60 m(2)/g. The performance of the aerogels as...

We describe the simple preparation of nitrocellulose gels and high surface area (300 + m(2) g(-1)) aerogels and their hierarchical pore structures. The solvent in which the gels form greatly influences the pore geometry and size distribution of the gels in both the macro- and mesopore domains.

While the low thermal conductivities of silica aerogels have made them of interest to the aerospace community as lightweight thermal insulation, the application of conformal polymer coatings to these gels increases their strength significantly, making them potentially useful as structural materials as well. In this work we perform multiscale computer simulations to investigate the tensile and c...

Aerogels refer to a new class of materials holding air in their structure. They are highly porous solids having a large inner surface area. They are extremely light, low heat conductive, and high sound absorbent materials. Therefore, aerogels have excellent performance in applications such as heat insulators, particle filters, particle trappers, and catalyst carriers 1 . Aerogels are prepared s...