Science Category Archive

Self Healing Plastic

Leave a reply Jonny Hankins

One of the problems with plastic is that it is very difficult to repair once damaged. When there is a hole in your plastic bucket you cannot generally mend it. But researchers in Spain have developed the world’s first self healing plastic.

Cutting the self healing plastic

Cutting the self healing plastic

Researchers at the CIDETEC Centre for Electrochemical Technologies in San Sebastian, Spain have developed a plastic that once broken can heal itself. All the user has to do is put the pieces together and leave it at room temperature for a couple of hours, and the material kind of re-molds itself. The repair is said to be 97% perfect within a couple of hours, and perfect 2 days later, and a Youtube video demonstrating the strength of the repair is really quite incredible.

Plastics are made up of polymers, a long chain of molecules that are connected through chemical bonds. Natural polymers are everywhere. In nature, many polymers heal themselves when broken or sliced. Think of your skin when you have a small cut — as the two sides of the cut bind back together, you’re witnessing a self-healing polymer in action.

Synthetic polymers are just as common. Scientists started creating nylon and synthetic rubber to make up for the shortage of silk and rubber during World War II. PVC, polyester and many forms of plastic soon followed.

Putting the pieces together

Putting the pieces together

The Spanish have developed the first human-made self-healing polymer to function without a catalyst, they report in the Sept. 13 issue of the journal Materials Horizon. There are in fact other self healing plastics, but they require a catalyst to start the process (ultra violet light for example). Readers might know about self scratch repair paint, as advertised on TV. This paint is made from prawn shells, a fine example of a natural self healing material that uses the sun as catalyst.

The article states that “The idea behind this is to reconnect the chemical crosslinks which are broken when a material fractures, restoring the integrity of the material. This is expected to provide polymers with enhanced lifetime and resistance to fatigue”.

Testing the repair

Testing the repair

The researchers say this breakthrough will allow them to create stronger sealants, paints, adhesives and more. This could eventually lead to self-repairing pipes, bicycle tires and toys, among a million other possibilities.

Sounds great to me, and the less plastic we throw away the better.

Sequencing Baby DNA, a Project in Boston

1 Reply Jonny Hankins

Last week the Science in Mind blog on my local Boston.com website ran an interesting story that is definitely worthy of reflection. It involves 2 local hospitals that are carrying out a project funded by the National Institute of Health (USA). The projects involve sequencing the DNA of newly born babies over the next 5 years. Read all about it here.

Babies to have their DNA sequenced

Babies to have their DNA sequenced

Now sequencing the DNA of babies carries with it several risks and ethical concerns, as well as well argued benefits. If we take the benefits first, doctors may gain information about a baby, such as high risk for a certain disease, genetic mutations that may require changes of lifestyle etc. They might also find explanations for problems that might otherwise go undetected.

There are though as I say risks and concerns. How will parents react if they discover that their baby has a high risk of an incurable disease? How will the knowledge gained through the test effect the way the parents view and behave towards their children? Are we giving families information that will change their understanding of parenting to such a degree that it might destroy the very fabric of their social relationships?

This is not to mention the social implications of giving out such information regarding extended family. If for example I am told that my baby has a genetic mutation carried by the parents that might have a serious effect on its life, should I tell my brothers and cousins so that they can screen their prospective wives, make decisions about having children or even worse a pregnancy already in course? And not to mention the obvious problem of discovering that the father is not the man stood in the room with the mother.

These problems are in fact the issues that the researchers running the project are hoping to look into. The question is if the clinical benefits outweigh the risks of such an approach.

I have written a lot about this subject in recent years if you would like more to read:

In June of last year I wrote a post here on Technology Bloggers called Sequencing the Genome of Unborn Babies. I also raised a lot of similar ethical concerns in May of the same year in Home Genetic Testing, Pros and Cons.

On the Bassetti Foundation we find DNA Privacy Issues from January of this year, a series called Architectures for Life from 2012 and a review of a book called Go Ask Your Father, just for starters.

My own personal view is that much of the promise peddled to us surrounding medicine and the sequencing of the human genome has yet to be delivered. One problem is money. Personalized medicine sounds like a great idea. I get my genome sequenced, we can see which drugs might work the best, the type of treatment I need etc. But drug companies cannot make, test and market a drug especially for me even with all of this information, it is just not cost effective. They want big sellers, generic medicines that work to some extent on everybody, not something that is fantastic for me with my particular gene pool.

There are clinical benefits, I am not arguing otherwise, but we must wait to see how great.

Protecting Our Coral Reefs

5 Replies Jonny Hankins

Last month the US military announced that they had dropped four unarmed bombs into Australia’s Great Barrier Reef Marine Park last week during a training exercise that went wrong. Two aircraft dropped two bombs each, one an inert practice bomb but the other an unarmed lazer guided explosive bomb into the World Heritage marine park. The bombs fell into an area away from the coral and the military report that they did not explode.

The action obviously caused outrage within the environmentalist and marine protection community, and it led me into looking into the state of our reefs today.

According to Global Coral Reef Monitoring Network we have lost 20% of the planet’s coral reef in the last 20 years. They also sate that a further 35% is in serious danger. We are talking about an area in total of 284,800 square kilometres of the seabed that is currently inhabited by coral.

A Coral Reef

A Coral Reef

Anyone who has ever been to the Great Barrier Reef will have seen the effects that mass tourism had on the reef in the past, before it became better regulated. Large parts of the reef lie dead. Overfishing is also one of the major causes for concern, as is climate change, the change in sea levels and the ever growing problem of rubbish (particularly plastics) that float around the reefs.

Recently however scientists at the University of Marche in Italy have discovered that some of the substances used in suncream could damage both the reefs and other maritime life. This presents another serious problem, as millions of us splash it on before going into the sea, washing zinc, various nanoparticles and petroleum derivatives into the water and over the reefs.

We could call it involuntary pollution, and we can debate the risk factor (risk to my skin versus risk to ocean life), but you will be pleased to hear that some cosmetic companies have started to produce a more ecologically sound form of suncream.

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The UK based company Aethic for example produce an Eco-compatible suncream called Sôvée, and they are working with King’s College London to develop a suncream that mimics the capacity that coral naturally has to protect itself from the sun’s rays.

Any development could have multiple uses, and at least help to remove one of the dangers that are threatening these structures.