PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

Off-the-shelf materials lead to self-healing polymers

2014-02-05
(Press-News.org) Contact information: Liz Ahlberg
eahlberg@illinois.edu
217-244-1073
University of Illinois at Urbana-Champaign
Off-the-shelf materials lead to self-healing polymers

CHAMPAIGN, Ill. — Look out, super glue and paint thinner. Thanks to new dynamic materials developed at the University of Illinois, removable paint and self-healing plastics soon could be household products.

U. of I. materials science and engineering professor Jianjun Cheng, graduate student Hanze Ying and postdoctoral researcher Yanfeng Zhang published their work in the journal Nature Communications.

"The key advantage of using this material is that it's catalyst-free and low-temperature, and can be healed multiple times," Cheng said. "These are very nice materials for internal cracks. This can heal the crack before it causes major problems by propagating."

Other self-healing material systems have focused on solid, strong materials. However, the new study uses softer elastic materials made of polyurea, one of the most widely used classes of polymers in consumer goods such as paints, coatings, elastics and plastics.

After the polymer is cut or torn, the researchers press the two pieces back together and let the sample sit for about a day to heal – no extra chemicals or catalysts required. The materials can heal at room temperature, but the process can be sped up by curing at slightly higher temperatures (37 degrees Celsius, or about body temperature). The polymer bonds back together on the molecular level nearly as strongly as before it was cut. In fact, tests found that some healed samples, stretched to their limits, tore in a new place rather than the healed spot, evidence that the samples had healed completely.

See a video demonstrating the preparation and self-healing properties at https://www.youtube.com/watch?v=1i3yoK0C9Ag.

The researchers use commercially available ingredients to create their polymer. By slightly tweaking the structure of the molecules that join up to make the polymer, they can make the bonds between the molecules longer so that they can more easily pull apart and stick back together – the key for healing. This molecular-level re-bonding is called dynamic chemistry.

Dynamic chemistry has been explored in some other polymers, but those materials tend to be for specialized applications or laboratory settings, rather than the conventional polymers used commercially. By focusing on consumer materials and using readily available ingredients, the researchers hope that manufacturers could easily integrate dynamic materials.

"We just buy commercial materials and mix them together, no fancy controls or special apparatus," said Cheng. "It's a very simple, low-cost, inexpensive process. Anybody can do this on any scale."

Now that they've established the chemistry required, the researchers are exploring how dynamic polyurea could bolster different applications. For example, they could fine-tune the mixture so that a polyurethane coating or paint could be removable.

"In some areas, when it's not necessary for the coating to be permanent and you want it to be removable, this chemistry may be applied to existing coating materials to make it reversible," Cheng said. "In general, polyurea and polyurethane are widely used. This chemistry could modify existing materials to make them more dynamic, healable."



INFORMATION:

The National Science Foundation and the National Institutes of Health supported this research. Cheng also is affiliated with the departments of chemistry and of bioengineering, the Beckman Institute for Advanced Science and Technology, the Institute for Genomic Biology, the Frederick Seitz Materials Research Laboratory and the Micro and Nano Technology Laboratory at the U. of I.

Editor's note: To contact Jianjun Cheng, call 217-244-3924; email jianjunc@illinois.edu. The paper, "Dynamic Urea Bond for the Design of Reversible and Self-healing Polymers," is available online.



ELSE PRESS RELEASES FROM THIS DATE:

Personal experience, work seniority improve mental health professionals' outlook

2014-02-05
One might think that after years of seeing people at their worst, mental health workers would harbor negative attitudes about mental illness, perhaps associating people with mental health ...

Telemedicine can reduce hospitalizations for nursing home residents

2014-02-05
LEBANON, NH (Feb. 4, 2014) – Telemedicine used at nursing homes during hours when doctors are not typically present is a viable way to reduce avoidable ...

New study shows core factors and strategies to turn primary care practices into PCMHs

2014-02-05
BOSTON – (February 4, 2014) – A new study conducted by Robert A. Gabbay, M.D., Ph.D., FACP, Senior Vice-President and Chief Medical Officer at Joslin Diabetes Center and Harvard ...

NASA satellite catches Australia's newborn Tropical Storm Edna and stubborn Fletcher

2014-02-05
Northeastern Australia has been watching two tropical low pressure areas over the last several days, and NASA's Aqua satellite captured both in one infrared image. Tropical Storm Edna ...

Fruit flies -- fermented-fruit connoisseurs -- are relentless party crashers

2014-02-05
That fruit fly joining you just moments after you poured that first glass of cabernet, has just used its poppy-seed-sized brain to conduct a finely-choreographed search, one that's been described ...

Taking statins to lower cholesterol? New guidelines

2014-02-05
ROCHESTER, Minn. — Feb. 4, 2014 — Clinicians and patients should use shared decision-making to select individualized treatments based on the new guidelines to prevent cardiovascular disease, according to a commentary ...

3D mapping biopsy finds 3x prostate cancer of ultrasound-guided biopsy

2014-02-05
Ultrasound-guided biopsies miss prostate cancers that are detected by the slightly more expensive and slightly more invasive 3D mapping biopsies. For example, in a 2006 study of 180 men diagnosed ...

AGU journal highlights -- Feb. 4, 2014

2014-02-05
The following highlights summarize research papers that have been recently published in Geophysical Research Letters (GRL), Journal of Geophysical Research-Solid Earth (JGR-B), and Paleoceanography. In this release: 1. Canada's ...

New study finds feeling 'in control' can help you live longer

2014-02-05
Do you believe in your own ability to succeed, or do you believe life events are largely beyond your control? Think carefully ...

Good hair day: New technique grows tiny 'hairy' materials at the microscale

2014-02-05
Scientists at the U.S. Department of Energy's Argonne National Laboratory attacked a tangled problem by developing a new technique to grow tiny "hairy" materials that assemble themselves ...

LAST 30 PRESS RELEASES:

Multi-resistance in bacteria predicted by AI model

Tinker Tots: A citizen science project to explore ethical dilemmas in embryo selection

Sensing sickness

Cost to build multifamily housing in California more than twice as high as in Texas

Program takes aim at drinking, unsafe sex, and sexual assault on college campuses

Inability to pay for healthcare reaches record high in U.S.

Science ‘storytelling’ urgently needed amid climate and biodiversity crisis

KAIST Develops Retinal Therapy to Restore Lost Vision​

Adipocyte-hepatocyte signaling mechanism uncovered in endoplasmic reticulum stress response

Mammals were adapting from life in the trees to living on the ground before dinosaur-killing asteroid

Low LDL cholesterol levels linked to reduced risk of dementia

Thickening of the eye’s retina associated with greater risk and severity of postoperative delirium in older patients

Almost one in ten people surveyed report having been harmed by the NHS in the last three years

Enhancing light control with complex frequency excitations

New research finds novel drug target for acute myeloid leukemia, bringing hope for cancer patients

New insight into factors associated with a common disease among dogs and humans

Illuminating single atoms for sustainable propylene production

New study finds Rocky Mountain snow contamination

Study examines lactation in critically ill patients

UVA Engineering Dean Jennifer West earns AIMBE’s 2025 Pierre Galletti Award

Doubling down on metasurfaces

New Cedars-Sinai study shows how specialized diet can improve gut disorders

Making moves and hitting the breaks: Owl journeys surprise researchers in western Montana

PKU Scientists simulate the origin and evolution of the North Atlantic Oscillation

ICRAFT breakthrough: Unlocking A20’s dual role in cancer immunotherapy

How VR technology is changing the game for Alzheimer’s disease

A borrowed bacterial gene allowed some marine diatoms to live on a seaweed diet

Balance between two competing nerve proteins deters symptoms of autism in mice

Use of antifungals in agriculture may increase resistance in an infectious yeast

Awareness grows of cancer risk from alcohol consumption, survey finds

[Press-News.org] Off-the-shelf materials lead to self-healing polymers