Opening of the Dry Rubber Laboratory, Department of Polymer Science

The ceremonial opening of the newly established Dry Rubber Laboratory of the Department of Polymer Science was held on 21st December 2022. The vice chancellor, Senior Prof. Sudantha Liyanage, the Dean of the Faculty of Applied Sciences, Prof. Upul Subasinghe, the Director of the Accelerating Higher Education Expansion & Development (AHEAD) programme, University of Sri Jayewardenepura, Prof. A. Harendra N. Kariyawasam, the staff members of the Department of Polymer Science accompanied by the Heads of the departments, the academic and non-academic staff members of the Faculty of Applied Sciences, and the students of the Department of Polymer Science graced this occasion. The newly opened Dry Rubber Laboratory is equipped with state-of-the-art facilities for rubber compounding (internal mixer, two roll mill, and molding press), testing rheological properties (moving die rheometer), and testing mechanical properties (universal tensile tester). This facility can be used to support student learning and caters to academic, research, and industrial needs.

Enhancing hyrdophobicity of natural rubber latex using diatomaceous earth

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.

rubber

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

 

Ag-Cellulose/CNT Composite for Molecular Detection

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)

ag-cellulose

Development of 2D Piezoresistive Sensor Using CNT/Rubber Composites

Piezoresistive materials can change their resistivity with respect to the applied pressure. Therefore, piezoresistive materials are used in the development of pressure sensors. This project focuses on developing MWCNT/rubber composites as piezoresistive materials, which could use for monitoring real-time pressure. For instance real-time monitoring of the terrain that an automobile is going on, quality of gasket, the assembling faults associated with aircraft body panels etc. Ongoing studies focus on developing both active material as well as digital algorithms for capturing piezoresistive behaviors of the developed composites. Further studies are to be conducted on building a prototype 2D pressure sensor that can monitor the real-time pressure variation using a mobile device via Bluetooth or Wi-Fi technology.

 

Manuscripts:

De Silva, D.J.; Abeysinghe, H.; Etamapwala, T.N.B.; Carbon Nanotube/Rubber Composites for Pressure Sensing Applications, MRS Advances (Submitted, 2022)

Competitions:

Submitted as an innovation proposal to the ‘Invenção’, Innovative idea competition 2022 organized by the Physics Society of University of Sri Jayewardenepura