Ordering takeaway or coffee to go is convenient, but it doesn’t take long for the food or coffee to cool down naturally. Thermos cups or insulated lunch boxes can solve this problem, but they are inconvenient to carry and not suitable for applications such as one-time use.
In addition, the currently widely used plastic packaging may become a source of white pollution after use, and some plastics will release microplastics under heating conditions, posing a threat to human health.
So, are there any materials that are easy to carry, environmentally friendly, low in price, and have thermal insulation properties?
Inspired by the skin of cephalopods (cuttlefish, squid and octopus, etc.), the University of California, Irvine team created an adaptive composite material that has the advantage of insulating and insulating. Therefore, it is suitable for beverage cups, takeaway packaging, parcel boxes, containers, etc.
It is worth noting that not only has the team come up with a feasible method of making the new material, but the cost of the raw materials (copper and rubber) for this composite material is only $0.1 per square meter, which is comparable to existing metal -The price of plastic film is comparable. Moreover, the production cost will be further reduced due to the expansion of the manufacturing scale, which lays a solid foundation for the commercial application of this material.
Recently, a related paper was published under the title “Scalable Manufacturing of Sustainable Packaging Materials with Tunable Thermal Regulation”.
The top layer of the composite material is copper, and the support layer is a brown rubber-like polymer. It is worth noting that this material can not only achieve heat preservation and freshness (delaying the degree of spoilage of food), but also adjust the temperature.
To this end, the researchers conducted a coffee cup experiment, which showed that they could not only predict the temperature accurately theoretically, but also use the experiment to clearly record its temperature changes. The team was also able to achieve a 20-fold modulation of infrared radiation transmittance and a 30-fold modulation of heat flux under standardized test conditions, a stable material that copes well even with high levels of mechanical deformation and repeated mechanical cycling. In terms of stability, the composite can maintain the tunable infrared function unchanged even after 10,000 strain cycles.
Reconfigurable metal structures play a key role in the material’s ability to regulate heat, which is characterized by separation from each other and secondary bonding at different strain levels.
”When the material relaxes, the metallic structures in our composite are adjacent to each other, and when the material is stretched, they separate, allowing control over the reflection and transmission of infrared light, or heat dissipation.” UC Irvine Chemistry, corresponding author of the paper “The mechanism is similar to the expansion and contraction of pigment
cells in squid skin, which changes the reflection and transmission of visible light,” Aaron Gorodsky, an associate professor in the Department of Engineering and Materials Science, told the media. How does it work? Generally speaking, squids use this change in their daily life to “transform” themselves in situations where they encounter danger or need to avoid. Inspired by this characteristic of squid, the composite can achieve a “temperature regulation” effect.
Take the use of this composite material for takeaway packaging as an example. On the one hand, it maintains the heat of the food and prevents rapid cooling; on the other hand, it also protects the human skin in contact with the takeaway packaging to avoid skin scalding due to the transfer of heat from the food to the packaging. Wait.
The commercial potential of the material lies in the fact that on the one hand, researchers have developed large-scale production in volumes rather than small-scale production in the laboratory. And its cost is low, and it is easier to be accepted in terms of quantitative production.
On the other hand, its commercial potential is also reflected in the environmentally friendly properties of the material. This composite material only needs to use vinegar to dissolve the copper component, and the remaining material can be recycled in batches through existing commercial channels.
Currently, the team is in the process of establishing contacts with a number of companies to confirm a viable path for their commercialization. The composite material is suitable for a variety of application scenarios that require temperature regulation, from disposable coffee cups, takeaway packaging, outdoor tents to space blankets, clothing, as an insulating layer material for buildings, effectively maintaining the temperature of valuable electronic components, and more.
”This material has numerous applications, such as in perishable goods being shipped to people’s homes during the pandemic,” said Gorodsky. “Any package that requires temperature control that is organic to consumers by e-commerce can use our self-made products.” Adaptive composite material for lining.”