Geotextiles are permeable fabrics which, when used in association with soil, have the ability to separate, filter, reinforce, protect, or drain.
Jute-based geotextiles are deployed to prevent soil loss from embankments, expose natural or cut slopes and instigate germination and vegetation growth on slope face to prevent shallow mechanical instabilities. They are also used in covering plants to protect them against frost.
In an interdisciplinary project, researchers took up the challenge of developing a chemical or biological process to make jute and other lignocellulosic fibres less hydrophilic (having affinity for water) and more degradation resistant largely using eco-friendly reagents without compromising the ductility and flexibility of the fibres.
"Chemically or biologically modified natural polymers are just baby steps in an effort towards sustainability in erosion control interventions," said Debasis Roy, lead researcher of the project.
The project involves Ramkrishna Sen from the department of biotechnology and Basudam Adhikari from Materials Science Centre.
Adhikari did the research on development of jute geotextiles and a suitable processing technique for rubber coating of jute, while Sen refined the microbial treatment segment required to develop the jute geotextiles with sustainable bioprocess integration and optimisation.
Laboratory testing has exhibited improved resistance of jute fibres and fabric against biological, chemical, UV and moisture related degradations.
Chemical treatment of jute fibres exhibited 75 per cent increase in tensile strength. Similarly, water absorption and equilibrium moisture content were reduced remarkably for yarns spun from treated fibres.
Laboratory studies and field experience also show a manifold increase in the longevity of the jute geotextiles that underwent the chemical treatment compared to their untreated counterparts.
The cost of treatment was found to be about Rs 17 to Rs 19 per square metre of woven jute fabric. These figures are remarkably lower than the costs of alternative treatments currently in use, the researchers said.
The team is now scouting for collaborators who could assist in commercial application of treated jute geotextiles in the construction industry.
