Category Archives: Research Highlights

Inspired by the superhydrophobic nature of lotus leafs, there have been many attempts taken to make surfaces with enhanced hydrophobicity. The incorporation of hydrophobic fillers is one way to increase hydrophobicity. The required nano-scale roughness and low surface energy requirements for these hydrophobic surfaces can be fulfilled by the use of fillers with nano-scale surface roughness and treatment with low surface energy compounds. One such example is the use of treated diatomaceous earth (DE). Although, natural rubber latex (NRL) is an inherently hydrophilic material, incorporating hydrophobicity to NRL films could make them useful for applications such as manufacture of hydrophobic rubber gloves, latex clothing, upper layers of a rubber boot or other single or multi-layered-products. It can also be used as a surface coating for existing rubber products. We report the use of hexadecyltrimethoxysilane treated DE to obtain NRL films with enhanced hydrophobicity. Surface wettability was analyzed by water contact angle (WCA) measurements. WCAs of about 115° was achieved with treated DE incorporated into NRL films. However, the resulting NRL films were harder and had smaller tensile strengths compared to normal NRL films.

Ambegoda, VT, Egodage, SM, Blum, FD, Maddumaarachchi, M. Enhancement of hydrophobicity of natural rubber latex films using diatomaceous earth. J Appl Polym Sci. 2021; 138:e50047

Aromatic molecules are ubiquitous environmental pollutants, which show a significant threat to human health because of their hazardous nature. Currently, many research works focus on developing rapid molecular detection techniques compared to time-consuming conventional detection methods with complicated procedures. Recently we have introduced a technique for rapid detection of phthalates in solutions in which we have used carbon nanotube (CNT) buckypapers and CNT/cellulose composite membranes as an electrochemical sensing materials. However, they have a limitation of detecting phthalates in dilute solutions, which is great disadvantage. Therefore in this study, Silver (Ag) incorporated cellulose is used with CNT to develop a highly sensitive phthalate sensing material. Based on the studies carried out so far, this developed material shows potential for detecting down to 1 ppm (v/v) concentrated phthalates in solutions. Further studies on increasing the sensitivity of the developed phthalate sensing cellulose/CNT material and developing an easy-to-use, real-time, and in-situ phthalate sensor are to be done.

Manuscripts:

Anuchani, P.; Abeysinghe, H.; Etampawala, T.N.B.; Ag-nanoparticle Decorated Cellulose/CNT Composite for Detection of Aromatic Molecules, MRS Advances (Submitted, 2022)

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.