Super-strong, super-stretchy material to be used as artificial skin

A new stretchy material has been developed that can lift an object one-thousand times its weight while still maintaining the ability to revert back to its original shape, when heated at body temperature.

Scientists at the University of Rochester believe that because of its flexibility their shape-memory polymer will be used as artificial skin but could also be useful when applying sutures, for body-heat assisted medical dispensers and for use as a wearable self-fitting apparel.

“Our shape-memory polymer is like a rubber band that can lock itself into a new shape when stretched,” said lead researcher, Mitch Anthamatten. “But a simple touch causes it to recoil back to its original shape.”

Image and featured image courtesy of Adam Fenster, University of Rocheste

Image and featured image courtesy of Adam Fenster, University of Rocheste

The shape-memory polymer works by controlling the crystallisation that occurs when the material is cooled or stretched.

As the material is deformed, polymer chains are stretched, and small segments of the polymer align in the same direction in small areas called crystallites.

These crystallites fix the material into a temporarily deformed shape, but as the number of crystallites grows, the polymer shape becomes more and more stable, making it increasingly difficult for the material to revert back to its initial shape.

To avoid the material becoming fixed in a deformed state the research team inserted molecular linkers to connect the individual polymer strands.

Anthamatten’s group discovered that linkers inhibit, but don’t stop, crystallisation when the material is stretched.

By altering the number and types of linkers used, as well as how they’re distributed throughout the polymer network, the university researchers were able to adjust the material’s structure and precisely set the point at which the material’s shape can be reverted.

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As well as being able to stretch and revert back to its original shape the new material has been optimised so that it can store as much elastic energy as possible.

As a result, the shape-memory polymer is capable of lifting an object one-thousand times its weight. For example, a polymer the size of a shoelace – which weighs about a gram – could lift a litre of soda.

“Tuning the trigger temperature is only one part of the story,” said Anthamatten. “We also engineered these materials to store large amount of elastic energy, enabling them to perform more mechanical work during their shape recovery”

Full details of the shape-memory polymer can be found in the Journal of Polymer Science Part B: Polymer Physics.

Rocket Lab’s battery-powered, 3D-printed rocket journeys into space

Silicon Valley funded space company Rocket Lab has today completed the maiden voyage of its low-cost, battery-powered and 3D-printed orbital class rocket.

Rocket Lab’s Electron rocket was launching from a private launch site on the Mahia Peninsula in New Zealand and represents the culmination of four years of preparatory work.

The company’s achievement will hopefully begin the process of removing the  financial and logistical barriers to space and provide unprecedented launches to low Earth orbit.

“It has been an incredible day and I’m immensely proud of our talented team,” said Peter Beck, CEO and founder of Rocket Lab.

“We’re one of a few companies to ever develop a rocket from scratch and we did it in under four years. We’ve worked tirelessly to get to this point. We’ve developed everything in house, built the world’s first private orbital launch range, and we’ve done it with a small team.

“It was a great flight. We had a great first stage burn, stage separation, second stage ignition and fairing separation. We didn’t quite reach orbit and we’ll be investigating why, however reaching space in our first test puts us in an incredibly strong position to accelerate the commercial phase of our programme, deliver our customers to orbit and make space open for business,” Beck said.

Although the Electron rocket wasn’t able to reach orbit on its first attempt, Rocket Lab has another two test flights scheduled for this year to achieve that goal.

Over the coming weeks, Rocket Lab’s engineers in Los Angeles and Auckland, New Zealand will work through the 25,000 data channels that were collected during Electron’s flight to optimise the vehicle for future journeys.

“We have learnt so much through this test launch and will learn even more in the weeks to come,” said Beck.

“We’re committed to making space accessible and this is a phenomenal milestone in that journey. The applications doing this will open up are endless. Known applications include improved weather reporting, internet from space, natural disaster prediction, up-to-date maritime data as well as search and rescue services.”

At full production, Rocket Lab expects to launch more than 50 times a year, and is regulated to launch up to 120 times a year.

The space innovation company already has plans to enter a “commercial phase”, which will see Electron fly already-signed customers including NASA, Spire, Planet, Moon Express and Spaceflight.

Next-generation spaceplane: DARPA and Boeing to make on-demand space launches a reality by 2020s

DARPA has taken a major step towards the creation of a new class of hypersonic aircraft that would offer low-cost, short-notice space launches, with the selection of The Boeing Company as its design partner.

Having already developed initial designs for the next-generation spaceplane, known as Experimental Spaceplane or XS-1, Boeing will now be tasked with completing detailed working designs, fabricating the craft and performing flight tests. The vehicle will be constructed and tested by 2019, before embarking on between 12 and 15 test flights in 2020.

Once completed, the plane will represent a major step forward in accessing space, allowing launches to be enacted within a matter of days, rather than the current timescale of months or years, and at a cost far lower than is currently the case.

“The XS-1 would be neither a traditional airplane nor a conventional launch vehicle but rather a combination of the two, with the goal of lowering launch costs by a factor of ten and replacing today’s frustratingly long wait time with launch on demand,” said Jess Sponable, DARPA program manager.

Designed to be completely re-useable, the unmanned XS-1 is around the same size as a business jet, and would take off vertically like a traditional rocket.

However, unlike a traditional rocket, it would require no external boosters to launch, instead being powered entirely by self-contained cryogenic propellants. Once the XS-1 arrived in subortbit, a booster would release a one-use upper stage to deploy the payload: a satellite, before the craft itself returned to Earth, landing horizontally like an aircraft.

Upon landing, the craft would be prepped for the next launch, and would be available to blast off again within a matter of hours. It is hoped that it will cut the cost of launch to below $5m per launch with frequent flights.

“We’re delighted to see this truly futuristic capability coming closer to reality,” said Brad Tousley, director of DARPA’s Tactical Technology Office (TTO).

“Demonstration of aircraft-like, on-demand, and routine access to space is important for meeting critical Defense Department needs and could help open the door to a range of next-generation commercial opportunities.”

Images courtesy of DARPA

Now Boeing has been selected to move forward with the spaceplane, it will face a very short timeframe in which to complete a working craft.

“We’re very pleased with Boeing’s progress on the XS-1 through Phase 1 of the program and look forward to continuing our close collaboration in this newly funded progression to Phases 2 and 3—fabrication and flight,” said Sponable.

From now until 2019, Boeing will be tasked with completing all design work and fabricating the spaceplane, before completing on-the-ground tests. These will require the aircraft to be fired 10 times in 10 days before a launch is attempted.

Once this stage is completed, Phase 3 will be launched, which will see the spacecraft complete between 12 and 15 test flights in 2020.

After these, the XS-1 will be subject to more rigorous flight tests, including 10 flights in 10 days, first without payloads, at speeds up to Mach 5. Eventually the spaceplane will be tested at Mach 10, and will deliver dummy payloads first at a fraction of and then the full weight of a satellite.