The fuel was made non-flammable: for this it was turned into a hydrogel

The developers considered the process of storing ethanol, a common liquid fuel, in a chemically cross-linked gel

poly-(N-isopropylacrylamide).They tested whether trapping ethanol molecules in PNIPAAm's long and chemically intertwined polymer chains helped reduce its evaporation rate. To test this, the researchers created small spheres of PNIPAAm gel filled with ethanol and placed them on an electronic balance to record how the mass changed as the ethanol evaporated. They also performed this experiment with an equivalent dose of ethanol with approximately the same surface area and mass as the gel sphere.

They found that storing ethanol in a polymergel completely suppresses the tendency of the fuel to evaporate quickly. This is likely due to the fact that the ethanol molecules are "trapped" in the gel, as Professor Hosoya explains: "A polymer gel contains countless three-dimensional polymer chains that are highly chemically cross-linked. These chains link the ethanol molecules through various physical interactions, limiting its evaporation in the process." Interestingly, the loaded gel does not behave like a wet towel. While a wet towel releases liquid when squeezed, the polymer gel does not release ethanol when exposed to external forces.

Having solved the problem of evaporation, the team moved on tostudying the actual combustion characteristics of ethanol in a polymer gel network to see if they burn efficiently. They ignited ethanol-filled gel spheres of various sizes and observed their mass and shape profiles in real time. Based on this, they determined that the combustion of the loaded PNIPAAm gel spheres consisted of two phases: a phase dominated by the combustion of pure ethanol, followed by a second phase dominated by the combustion of the PNIPAAm polymer itself.

Through subsequent theoretical analysisFrom these results, the team reached an important conclusion: the first and main combustion phase of the loaded PNIPAAm gel spheres follows a constant temperature droplet model. This means that the combustion of gel with ethanol can be described by the same model as for droplets of liquid fuel, hinting that their combustion characteristics should be similar.

"Storing polymer gel can preventexplosions and fires due to a sharp reduction in fuel evaporation and, in turn, the formation of flammable gas mixtures, which can easily occur as a result of a leak in the storage facility,” explains Professor Hosoya. 

High Energy Density Liquid Fuelnecessary in many applications where chemical energy is converted into controlled motion, such as in rockets, gas turbines, boilers, and some vehicle engines. In addition to combustion characteristics and performance, it is also important to ensure the safety and stability of these fuels during use, as well as during transport and storage.

One of the common hazards when working withliquid fuel is that it can quickly evaporate in a confined space, forming clouds of flammable gases. This may cause explosions or fires. To solve this problem, the researchers considered the possibility of using thickened fuels or fuels that turn into thick gel-like substances at low temperatures. Unfortunately, there are many aspects that need to be optimized and hurdles to overcome before gelled fuels can move beyond the research phase.

Read more:

Look at the "silent" drone with a new generation of ion propulsion

Ancient trilobite males strapped females on during mating

Russia and the United States have Doomsday planes: how and where they will fly in the event of the end of the world