From compost to composites: An eco-friendly way to improve rubber

February 21, 2018, American Chemical Society
Credit: American Chemical Society

The concept of "from trash to treasure" holds true for the world of composting, where food waste is recycled into fertilizer for gardens. But what if compost could go beyond fertilizer? Now, one group reports in ACS Omega that by collecting the gases produced during the compost process, they can combine it with rubber to make optimized electronic sealants and sensors.

Natural is obtained by tapping the Hevea brasiliensis tree and having a little patience. This polymer is used in everyday items from tires to rainboots because of its flexibility, elasticity and durability. But usually isn't pure by the time it hits the pavement. Manufacturers have added fillers, such as carbon black, to it to enhance its properties. Because carbon black is needed in large amounts that negatively affect the rubber's color and other properties, scientists have been looking for an alternative to completely or partially replace it. One option being explored is graphitic nanocarbons as fillers. Alain Pénicaud and colleagues set out to make nanocarbon fillers that are more cost-efficient and consistent in size than others being developed.

The team used graphitic nanocarbons derived from the methane produced by decomposing food, or compost, which is inexpensive and sustainable. In addition, the nanocarbons were small and consistently sized, meaning they would be ideal for fillers. The were combined with natural rubber to form a composite. Upon testing, the composite's was verified, which the researchers say shows that the material could be applied as a sealant for electrical devices. The composite only gained conductivity when loaded with 10 wt percent of the nanocarbons, a potential application for developing sensors. The group concluded that the nanocarbons were a viable competitor to carbon black as a filler. Watch this Headline Science video to see this material in action.

Explore further: Turning food waste into tires: Eggshells, tomato peels add strength to sustainable rubber

More information: Katerina Kampioti et al. Highly Conducting, Sustainable, Nanographitic Rubber Composites, ACS Omega (2018). DOI: 10.1021/acsomega.7b01848

Environmentally friendly multifunctional rubber composites are reported. Graphitic nanocarbon (NC) deriving from cracking of biogas (methane/carbon dioxide) and natural rubber extracted directly from the Hevea brasiliensis tree are the two components of these composites produced via latex technology. While maintaining and enhancing the intrinsic thermal and mechanical characteristics of rubber, the presence of NC shows a significant improvement on the electrical response. For a 10 wt % NC content, a 1010-fold increase in conductivity has been achieved with a conductivity value of 7.5 S·m–1, placing these composites among the best obtained using other carbon fillers. In addition, the piezoresistive behavior has also been verified. These promising green composites have a potential use in a variety of applications such as sealing of electronic devices and sensors.

Related Stories

Researchers develop highly stretchable aqueous batteries

January 26, 2018

The current development of stretchable battery materials that mimic the functions of nature has emerged for the next wave of wearable electronics. A recent study presented a bioinspired Jabuticaba-like hybrid carbon/polymer ...

Graphene makes rubber more rubbery

May 20, 2016

In an article published in Carbon, Dr Aravind Vijayaraghavan and Dr Maria Iliut from Manchester have shown that adding a very small amount of graphene, the world's thinnest and strongest material, to rubber films can increase ...

Natural rubber from dandelions

June 8, 2015

Dandelions are modest plants that are an excellent alternative source for a raw material of high demand: natural rubber, the fundamental ingredient in rubber products. Fraunhofer researchers have established the basis for ...

Tapping into the rubber plant genome

February 7, 2013

A group of international scientists have sequenced the draft genome sequence of the rubber tree Hevea brasiliensis, the major commercial source of natural rubber. The manuscript describing the draft genome is published in ...

Some smart ways to jumpstart your recycling program

January 25, 2018

(HealthDay)—Working toward a healthier environment involves more than separating glass and plastic. Try a new take on the three "R's"—recycle, reduce and reuse—to save money, energy and natural resources.

Recommended for you

Programming DNA to deliver cancer drugs

March 19, 2018

DNA has an important job—it tells your cells which proteins to make. Now, a research team at the University of Delaware has developed technology to program strands of DNA into switches that turn proteins on and off.

Modified biomaterials self-assemble on temperature cues

March 19, 2018

Biomedical engineers from Duke University have demonstrated a new approach to making self-assembled biomaterials that relies on protein modifications and temperature. The hybrid approach allows researchers to control self-assembly ...

Identifying 'designer' drugs taken by overdose patients

March 19, 2018

Drug overdoses are taking a huge toll on public health, with potent synthetic drugs posing a particular threat. Medical professionals are scrambling to meet the growing demand for emergency room treatment, but they're hampered ...

The Swiss army knife of smoke screens

March 18, 2018

Setting off smoke bombs is more than good fun on the Fourth of July. The military uses smoke grenades in dangerous situations to provide cover for people and tanks on the move. But the smoke arms race is on. Increasingly, ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.