@article {43871, title = {Capillary uptake in macroporous compressible sponges}, journal = {Soft Matter}, volume = {13}, year = {2017}, month = {SEP}, chapter = { 5731-5740}, abstract = {

The capillarity-driven uptake of liquid in swellable, highly porous sponges is of significant industrial importance. Sponges prepared using polymers and their composites with carbon nanotubes and graphene have been reported, with extraordinary solvent uptake capacities and with the ability to separate oil from water. However, the effect of systematic variation of sponge characteristics on solvent uptake has not been investigated. Here, we report experiments that study capillary uptake in a variety of flexible, centimetre-sized macroporous cylindrical sponges. We used ice-templating to prepare a series of model macroporous sponges in which the porosity, modulus and composition were systematically varied. We investigated two kinds of sponge: (a) those composed purely of cross-linked polymers and (b) those prepared as composites of inorganic particles and polymers. Both kinds of sponge are flexible and exhibit elastic recovery after large compressive deformation. All sponges were characterized thoroughly with respect to their pore microstructure and elastic modulus. When one end of a sponge is plunged into a large reservoir, water rises through capillary action against gravity. We observed a transition from an inertial capillary regime, where the liquid column height rose linearly with time, t, to a viscous capillary regime, where the liquid height rose with time t(0.5). We showed that these results can be rationalized using analyses developed for rigid sponges. We combined differential momentum balance equations for uptake in rigid capillaries with the phenomenological Ergun-Forchheimer relations to account for the effect of the sponge microstructure. This approach works remarkably well in the viscous capillary regime and shows that capillary uptake is governed primarily by the total porosity and pore dimensions of soft sponges.

}, keywords = {aerogels, Building blocks, Catalyst Supports, Contact-angels, Dynamics, flow, Organic Liquids, Porous-Media, Rise}, issn = {1744-683X}, doi = {10.1039/c7sm00826k}, author = {Chatterjee, Soumyajyoti and Doshi, Pankaj and Kumaraswamy, Guruswamy} } @article {48758, title = {Thermally activated delayed fluorescent solvent-free organic liquid hybrids for tunable emission applications}, journal = {Chemistry-An Asian Journal}, volume = {18}, year = {2023}, month = {JUL }, type = {Article}, abstract = {

The synthetic feasibility and excellent luminescence features of organic molecules attracted much attention and were eventually found useful in lighting applications. In this context, a solvent-free organic liquid having attractive thermally activated delayed fluorescence features in bulk along with high processability has prime importance. Herein, we report a series of naphthalene monoimide-based solvent-free organic liquids exhibiting cyan to red thermally activated delayed fluorescence with luminescence quantum yields up to 80\% and lifetimes between 10 to 45 mu s. An effective approach explored energy transfer between liquid donors with various emitters exhibiting tunable emission colors, including white. The high processability of liquid emitters improved the compatibility with polylactic acid and was used for developing multicolor emissive objects using 3D printing. Our demonstration of the thermally activated delayed fluorescence liquid will be much appreciated as a processable alternate emissive material suitable for large-area lighting, display, and related applications.

}, keywords = {3D printing, Energy Transfer, OLED, Organic Liquids, TADF}, issn = {1861-4728}, doi = {10.1002/asia.202300276}, author = {Nidhankar, Aakash D. D. and Goudappagouda and Kothavade, Premkumar D. and Dongre, Sangram D. and Veer, Sairam Dnyaneshwar and Dash, Soumya Ranjan and Rajeev, Kavya and Unni, K. N. Narayanan and Shanmuganathan, Kadhiravan and Babu, Sukumaran Santhosh} }