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Industrialization has caused high water pollution with the continuous release of harmful chemicals like dyes and pesticides. The aim of this research work to produce a polymer membrane embedded with rice husk silica to filter wastewater that would retain harmful chemicals. The polymer membrane is made out of poly(vinyl alcohol) and poly ethylene glycol by embedding with the rice husk ash derived silica which is prepared using the novel method of spray drying of sodium silicate in the presence of CO₂ gas. We found that the amorphous nature of the rice husk silica highly adsorb cationic dyes. However, it does not adsorb anionic dyes. This novel filtration membrane acts as a quick, cheap and as well as selective membrane in filtration harmful dyes and its potential to filter out pesticides is currently undergoing.

Natural rubber based nanocomposites have current and potential applications in many fields. Mostly the nanomaterial are incorporated to rubber lattices during the compounding stage. However homogeneours dispersion of nanomaterial in rubber matrix is very challenging.

In this research we are trying to develop a spray drying process to improve the dispersion of carbon based nano materials such as graphite and carbon nanotubes in rubber lattices. The nanomaterils is first homogenized in latex and then spray dried to get well-dispersed nanomaterils in dry rubber matrices. So far we have achieved the well dispersed graphite in spray dried NR lattice and they have been compounded to make rubber sheets.

Table 01: The mechanical performance of rubber sheets

The mechanical properties of the rubber sheets made out of spray dried rubber is much better than that of the rubber sheets made out of conventional rubber compounding processes. Our ultimate goal is to develop a laboratory scale spray drying setup for spray drying latex containing nonmaterial.

In this project we are developing a textile material that provides protection against NIR and UV radiation. Spandex and nylon are selected as the textile materials since it is the widely used textile material to make sportswear. People who are engaged in outdoor sports activities expose to solar radiation often. Exposure to solar radiation can cause health issues such as skin and eye cancers, changes in biological genomes, etc. The active material that prevents entering the UV through the textile and reflecting the NIR is ZnO. In order to get the optimum performance ZnO particles must be on the surface of the textile fibrils. Polydopamine (PDA) is used as an adhesive to incorporate these ZnO onto spandex/nylon fibrils. Catechol groups in PDA make bonds with amide groups in the textile substrate and the hydroxyl groups in the ZnO nanoparticle surface. Therefore, the ZnO nanoparticles will immobilize on the textile surface and the ZnO nanoparticles can efficiently absorb UV radiation and reflect NIR radiation. Such textile materials have already prepared and currently the performances are being characterized.