A new material that stiffens 1,800-fold when exposed to heat could protect motorcyclists and racecar drivers during accidents.
Hokkaido University researchers have developed a hydrogel that does the opposite of what polymer-based materials, like plastic bottles, normally do: their material hardens when heated and softens when cooled. Their findings, published in the journal Advanced Materials, could lead to the fabrication of protective clothing items for traffic and sports-related accidents.
Takayuki Nonoyama and Jian Ping Gong of Hokkaido University and their colleagues were inspired by how proteins remain stable inside organisms that survive within extreme-heat environments, like hot springs and deep sea thermal vents. Normally, heat “denatures” proteins, altering their structure and breaking their bonds. But the proteins within thermophiles remain stable with heat thanks to enhanced electrostatic interactions such as ionic bonds.
The team developed an inexpensive, non-toxic polyacrylic gel based on this concept. A gel composed of polyelectrolyte poly (acrylic acid) (PAAc) was immersed in a calcium acetate aqueous solution. PAAc on its own acts like any other polymer-based material and softens when heated. But when calcium acetate is added, PAAc’s side residues interact with the calcium acetate molecules, in a way similar to what happens inside thermophile proteins, causing PAAc to act very differently.
The team found that their originally uniform gel separates into a polymer dense “phase” and a polymer sparse one as the temperature rises. When it reaches to a critical temperature, in this case around 60°C, the dense phase undergoes significant dehydration which strengthens ionic bonds and hydrophobic interactions between polymer molecules. This causes the material to rapidly transform from a soft, transparent hydrogel to a rigid, opaque plastic.
The heated material was 1,800 times stiffer, 80 times stronger, and 20 times tougher than the original hydrogel. The soft-to-rigid switching was completely reversible by alternatively heating and cooling the material. Moreover, the scientists could fine-tune the switching temperature by adjusting the concentration of the ingredients.
They then demonstrated a possible application of the material by combining it with a woven glass fabric. This new fabric was soft at room temperature, but when it was pulled against an asphalt surface for five seconds at a speed of 80 km/hour, the heat generated by the friction hardened the material with only minor abrasions forming on the contact surface.
Takayuki Nonoyama says “Clothing made from similar fabric could be used to protect people during traffic or sports-related accidents, for example. Our material could also be used as a heat-absorbent window coating to keep indoor environments cooler.”
“This polymer gel can be easily made from versatile, inexpensive and non-toxic raw materials that are commonly found in daily life. Specifically, the polyacrylic acids are used in disposable diapers and calcium acetates are used in food additives,” Jian Ping Gong added. “Our study contributes to basic research on new temperature-responsive polymers, and to applied research on temperature-responsive smart materials.”
Learn more: Bio-inspired hydrogel can rapidly switch to rigid plastic
Go deeper with Bing News on:
Temperature-responsive smart materials
- The best Amazon deals to shop this week: Save up to 80% on Mother's Day gifts, tech gadgets, gardening essentials and more
These No. 1 bestselling head cushions are cult favorites among Amazon shoppers, and Yahoo readers also can't stop scooping them up. They're made of a cooling gel to help keep those uncomfortable night ...
- Constructing Tomorrow: Leveraging AI In The Building Industry
The integration of AI into architectural practices has the potential to redefine how buildings are designed, constructed and operated.
- Even Non-Techy Folks Will Love the Ray-Ban Meta Smart Glasses
I tried out the Ray-Ban Meta smart glasses, and found them to be perfect for taking photos and listening to music. Read my full review with photos here.
- How Green Technologies Are Reshaping Air Conditioning
As we grapple with global warming and rising global temperatures, air conditioning is no longer just about comfort but a necessity in many parts of the world. The first modern air conditioning system, ...
- Climate-smart routines: Geoskincare takes centre stage in beauty trends for 2024
Geoskincare is one of the main trends our teams identified as shapers of the cosmetic industry in 2024. In today’s changing world, there is no doubt Geoskincare is bound to be adopted as a holistic ...
Go deeper with Google Headlines on:
Temperature-responsive smart materials
[google_news title=”” keyword=”temperature-responsive smart materials” num_posts=”5″ blurb_length=”0″ show_thumb=”left”]
Go deeper with Bing News on:
Temperature-responsive polymers
- Advancing responsive colloidal nanomaterials with virus-polymer crystals
Besides illuminating the fundamental forces governing nanoparticle self-assembly, the study presents a practical method for organizing functional biomolecules into responsive materials with emergent ...
- New Smart Adhesive with Unmatched Strength and Versatility
According to a study published in the National Science Review , scientists at Nanyang Technological University in Singapore (NTU Singapore) have developed a smart, reusable adhesive. This new adhesive ...
- World-Leading Scientist Delivers Annual Aston University Distinguished Lecture on the Marvels of Smart Gels
Dr Raghunath Anant Mashelkar delivered Aston University’s 2024 Annual Distinguished Lecture to more than 70 invited guests on 22 April.One of the world’s renowned figures in polymer science, research ...
- Polymers news
A new development in biomedical research could open the door to a variety of new applications: Scientists at the University of Bayreuth have found that certain polymers, called polyanions ...
- Quick-drying polymer may be key to more energy-efficient buildings
Also, in contrast to a traditional air conditioner, the desiccant would likely not need to be heated to high temperatures to evaporate the ... in her lab are developing a range of thermo-responsive ...
Go deeper with Google Headlines on:
Temperature-responsive polymers
[google_news title=”” keyword=”temperature-responsive polymers” num_posts=”5″ blurb_length=”0″ show_thumb=”left”]