Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Biodegradable reinforced plastics could replace landfills with compost heaps, Cornell fiber scientist believes

10.09.2002


Instead of landfills clogged with computer and car parts, packaging and a myriad of other plastic parts, a Cornell University fiber scientist has a better idea. In coming years, he says, many of these discarded items will be composted.



The key to this "green" solution, says researcher Anil Netravali, is fully biodegradable composites made from soybean protein and other biodegradable plastics and plant-based fibers, developed at Cornell and elsewhere.

"These new fully biodegradable, environment-friendly green composites have good properties and could replace plastic parts in the interiors of cars and trains, in computers and in packaging materials and other consumer products," says Netravali, a professor of fiber science in the College of Human Ecology at Cornell. "They also provide excellent insulation against heat and noise for use in applications such as cars. Although the plant-based fibers may not be as strong as graphite and Kevlar®, for example, they are low in cost, biodegradable and replenishable on a yearly basis," he says.


Netravali’s findings are published in the September issue of the Journal of Materials Science .

He presented his research on green composites made from ramie fibers (which have a feel similar to silk) at the International Conference on Composites Engineering in Denver two years ago and in San Diego this summer. Ramie fibers are obtained from the stem of an Asian perennial shrub and the resin made from a soy protein isolate-polymer. He did this work in collaboration with Preeti Lodha, a graduate student who received her master’s degree from Cornell in 2000, and Sunghyun Nam, who completed her master’s in fiber science earlier this year.

Instead of nondegradable plastics based on petroleum products, green composites (also known as reinforced plastics) use natural fibers that, for strength, are embedded in a matrix made of a plant-based or other resin. Netravali points out that composites technology is not new -- he cites primitive bricks and walls made of straw mixed with mud as examples.

Netravali notes that most nondegradable plastic composites, made from petroleum-based or synthetic polyurethane, polyethylene and polypropylene, end up in landfills. Not much can be reused or recycled. Plant-based green composites, however, could, he says, become inexpensive alternatives for many mass-produced items. "They will be made from yearly renewable agricultural sources and would be environmentally friendly because they would naturally biodegrade once they were thrown on a compost pile."

Netravali’s research group is working with a number of fibers, including those obtained from kenaf stems, pineapple and henequen leaves and banana stems. The resin materials he is researching include commercial resins, such as polyvinyl alcohol and polylactones, and those derived from microorganisms. He currently is manipulating the composites to improve their mechanical properties, such as stiffness and strength, and to decrease their water absorption, which could start premature degradation.

The new composites could also substitute for wood in such applications as crates or building studs. "Trees take 25 years to grow; fibers we use, however, come from plants that grow to maturity in a year," Netravali points out.

Netravali agrees that green composites are likely to be more expensive than nonbiodegradable plastics, but as they gain acceptance and the volume increases, they will become less expensive, he says. For example, graphite fibers, commonly used as a reinforcement in space applications, cost over $180 a pound when first developed. Today they are less than $10 a pound.

Susan S. Lang | EurekAlert!
Further information:
http://www.news.cornell.edu/releases/Sept02/green.plastics.ssl.html

More articles from Ecology, The Environment and Conservation:

nachricht Foxes in the city: citizen science helps researchers to study urban wildlife
14.12.2018 | Veterinärmedizinische Universität Wien

nachricht Machine learning helps predict worldwide plant-conservation priorities
04.12.2018 | Ohio State University

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Data storage using individual molecules

Researchers from the University of Basel have reported a new method that allows the physical state of just a few atoms or molecules within a network to be controlled. It is based on the spontaneous self-organization of molecules into extensive networks with pores about one nanometer in size. In the journal ‘small’, the physicists reported on their investigations, which could be of particular importance for the development of new storage devices.

Around the world, researchers are attempting to shrink data storage devices to achieve as large a storage capacity in as small a space as possible. In almost...

Im Focus: Data use draining your battery? Tiny device to speed up memory while also saving power

The more objects we make "smart," from watches to entire buildings, the greater the need for these devices to store and retrieve massive amounts of data quickly without consuming too much power.

Millions of new memory cells could be part of a computer chip and provide that speed and energy savings, thanks to the discovery of a previously unobserved...

Im Focus: An energy-efficient way to stay warm: Sew high-tech heating patches to your clothes

Personal patches could reduce energy waste in buildings, Rutgers-led study says

What if, instead of turning up the thermostat, you could warm up with high-tech, flexible patches sewn into your clothes - while significantly reducing your...

Im Focus: Lethal combination: Drug cocktail turns off the juice to cancer cells

A widely used diabetes medication combined with an antihypertensive drug specifically inhibits tumor growth – this was discovered by researchers from the University of Basel’s Biozentrum two years ago. In a follow-up study, recently published in “Cell Reports”, the scientists report that this drug cocktail induces cancer cell death by switching off their energy supply.

The widely used anti-diabetes drug metformin not only reduces blood sugar but also has an anti-cancer effect. However, the metformin dose commonly used in the...

Im Focus: New Foldable Drone Flies through Narrow Holes in Rescue Missions

A research team from the University of Zurich has developed a new drone that can retract its propeller arms in flight and make itself small to fit through narrow gaps and holes. This is particularly useful when searching for victims of natural disasters.

Inspecting a damaged building after an earthquake or during a fire is exactly the kind of job that human rescuers would like drones to do for them. A flying...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

ICTM Conference 2019: Digitization emerges as an engineering trend for turbomachinery construction

12.12.2018 | Event News

New Plastics Economy Investor Forum - Meeting Point for Innovations

10.12.2018 | Event News

EGU 2019 meeting: Media registration now open

06.12.2018 | Event News

 
Latest News

When a fish becomes fluid

17.12.2018 | Studies and Analyses

Progress in Super-Resolution Microscopy

17.12.2018 | Life Sciences

How electric heating could save CO2 emissions

17.12.2018 | Power and Electrical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>