Is there a low-cost, eco-friendly alternative to the plastic used in car interiors? A composite of jute and soy resin could possibly do the job, say researchers at the Indian Institute of Technology, Kharagpur, who recently demonstrated a simple technique without the use of chemical solvents to prepare jute fibres that were strong enough and bio-degradable.

While jute has long been pitched as an alternative for plastics, its water-loving nature has typically posed a challenge in preparing composites with thermoplastic resins that are ‘hydrophobic’ apart from the fact that these composites are not fully bio-degradable.

That same property, however, also proves to be an advantage in making eco-friendly composites with a hydrophilic resin such as soy, says the paper. The protein-rich bean has previously been used – in the form of soy protein concentrate or soy protein isolate – as the matrix for developing natural ?bre reinforced composites.

By using soy milk extracted from soaked soy seeds, however, the process of developing the jute composites is cheaper than either bio-resin and also takes less time, the researchers say. ?Though signi?cant amount of work has been reported on natural ?bre and bio-resin-based composite, no literature report is available on the use of soy milk as resin with jute woven or non-woven fabric to prepare eco-friendly jute composite,? says the paper published in the journal Carbohydrate Polymers, in January. ?We have developed 5-6 products for which we are now talking to companies,? says Ramakrishna Sen, associate professor at the IIT Kharagpur’s Department of Biotechnology who co-authored the paper. Some of the products have been patented, he said. ?Our final goal is to use it in car interiors or panels. We are targeting the railways sector also, but it may take some time.?

Sen and his co-workers soaked jute felts and fabric in the soy resin which were then dried and compressed to obtain the composites. ?The novelties of this work are use of water as solvent for soy resin preparation instead of any organic solvent and jute without any chemical treatment,? says the paper, which notes that a composite prepared with jute weight of 60% showed highest tensile strength. ?Water absorption of these composites is moderately high, which can be reduced by using a different resin modifer,? it says.

In a test for bio-degradation, the researchers found that the soy resin degraded the most with 52% loss in weight after seven days buried under soil while the woven-jute

soy composite and non-woven jute soy composite degraded by 23% and 26%, respectively. After 60 days, the soy resin lost 92% of its weight while the woven jute composite and non-woven composite showed 60% and 64% weight loss, respectively.

Jute, known for its high tensile strength, is grown mostly in India?s eastern states. Raw jute production in the country is estimated to be 10.9 million bales in 2011-12. The output of the jute goods industry was estimated at 1.5 million tonne in 2010-11, most of it for sacking.

Several other uses for jute composites, however, have been devised over the years including apparel, handicraft and furniture, besides its application in roofing, plumbing or building interiors. ?There is a lot of scope for jute geotextiles in the control of soil erosion. The only challenge is that they have to be manufactured on a large scale,? says D Paul, former principal scientist at the Kolkata-based National Institute of Research on Jute and Allied Fibre Technology, an arm of the Indian Council of Agricultural Research. Jute geotextiles are being used in applications such as building embankments or road construction.

Sen reckons that developing suitable equipment for the treatment of the jute

to produce the composite would be the

main challenge his group would face in

taking their techniques from laboratory stage to a pilot project.

Statfacts

Alternative to plastic

* IIT-K researchers develop bio-degradable jute composite using soy resin

* Their technique of extracting soy milk cheaper than is the case with bio-resin

* India?s raw jute production estimated at 10.9 million bales in 2011-12

* The jute goods industry output was 1.5 mt in 2010-11, most of it for sacking

* Jute composites are being promoted as an alternative to plastic