PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

Chalk-based coating creates a cooling fabric

Chalk-based coating creates a cooling fabric
2024-08-21
(Press-News.org) DENVER, Aug. 21, 2024 — In the scorching heat of summer, anyone who spends time outside — athletes, landscapers, kids at the park or beachgoers — could benefit from a cooling fabric. While there are some textiles that reflect the sun’s rays or transfer heat away from the body, current options require boutique fibers or complex manufacturing processes. But now, researchers report a durable chalk-based coating that cools the air underneath treated fabric by up to 8 degrees Fahrenheit.

Evan D. Patamia, a graduate student at the University of Massachusetts Amherst, will present their team’s results at the fall meeting of the American Chemical Society (ACS). ACS Fall 2024 is a hybrid meeting being held virtually and in person Aug. 18-22; it features about 10,000 presentations on a range of science topics.

“If you walk out into the sunlight, you will get increasingly hot because your body and clothing are absorbing ultraviolet (UV) and near-infrared (near-IR) light from the sun,” says Trisha L. Andrew, a chemist and materials scientist working with Patamia. “And as long as you’re alive, your body is generating heat, which can be thought of as light, too.”

To make people more comfortable outside, scientists have been developing textiles that simultaneously deflect the sun’s rays and push out natural body heat — a process known as radiative cooling. Some of those materials have light-refracting synthetic particles, such as titanium dioxide or aluminum oxide, embedded into spun fibers. Others use organic polymers, such as polyvinylidene difluoride, which require perfluoroalkyl and polyfluoroalkyl substances, known as PFAS or forever chemicals, in their production processes to create light-reflective textiles.

But scaling the manufacturing of these materials for commercialization isn’t sustainable, according to Andrew. So, she posed the question to research team members Patamia and Megan K. Yee, “Can we develop a textile coating that does the same thing using natural or environmentally benign materials?”

Previously, Andrew and colleagues created a simple technique to apply durable polymer coatings on fabric called chemical vapor deposition (CVD). The method combines synthesis and deposition into the same step: grafting a thin polymer layer onto commercial textiles with fewer steps and less environmental impact than other ways to attach coatings.

So, inspired by the crushed limestone-based plasters used historically to keep houses cool in extremely sunny places, Patamia and Yee worked on innovating a process to integrate calcium carbonate — the main component in limestone and chalk — as well as bio-compatible barium sulfate onto the polymer applied by CVD. Small particles of calcium carbonate are good at reflecting visible and near-IR wavelengths, and barium sulfate particles reflect UV light.

Treating small squares of fabric, the researchers applied a 5-micrometer-thick poly(2-hydroxyethyl acrylate) layer and repeatedly dipped the polymer-treated squares into solutions containing calcium or barium ions and solutions containing carbonate or sulfate ions. With each dip, the crystals become larger and more uniform, and the fabric develops a chalky, matte finish. Patamia says that by changing the number of dipping cycles, the particles can be tuned to reach the ideal size distribution (between 1 and 10 micrometers in diameter) for reflecting both UV and near-IR light.

The researchers tested the cooling abilities of treated and untreated fabrics outside on a sunny day when the temperature measured more than 90 F. They observed air temperatures underneath the treated fabric that registered 8 F cooler than the ambient temperature in the middle of the afternoon. The difference was even greater, a maximum of 15 F, between treated and untreated fabric, which heated the air underneath the sample. “We see a true cooling effect,” says Patamia. “What is underneath the sample feels colder than standing in the shade.”

As a final evaluation of the mineral-polymer coating, Yee simulated the friction and impact of laundry detergent in a washing machine. She found that the coating didn’t rub away and the material retained its cooling ability.

“So far in our processes, we’ve been limited by the size of our laboratory equipment,” says Andrew. But she’s part of a startup company that’s scaling the CVD process for bolts of fabric, which are about 5 feet wide and 100 yards long. Andrew explains that this venture could provide a way to translate Patamia and Yee’s innovations into pilot-scale production.

“What makes our technique unique is that we can do this on nearly any commercially available fabric and turn it into something that can keep people cool,” concludes Patamia. “Without any power input, we’re able to reduce how hot a person feels, which could be a valuable resource where people are struggling to stay cool in extremely hot environments.”

The research was funded by the U.S. National Science Foundation. Trisha L. Andrew is involved in commercializing the polymer coating process.

A Headline Science video about this topic will be posted on Wednesday, Aug. 21. Reporters can access the video during the embargo period, and once the embargo is lifted the same URL will allow the public to access the content. Visit the ACS Fall 2024 program to learn more about this presentation, “Functional reflective textile coatings for personal cooling,” and other science presentations.

###

The American Chemical Society (ACS) is a nonprofit organization chartered by the U.S. Congress. ACS’ mission is to advance the broader chemistry enterprise and its practitioners for the benefit of Earth and all its people. The Society is a global leader in promoting excellence in science education and providing access to chemistry-related information and research through its multiple research solutions, peer-reviewed journals, scientific conferences, eBooks and weekly news periodical Chemical & Engineering News. ACS journals are among the most cited, most trusted and most read within the scientific literature; however, ACS itself does not conduct chemical research. As a leader in scientific information solutions, its CAS division partners with global innovators to accelerate breakthroughs by curating, connecting and analyzing the world’s scientific knowledge. ACS’ main offices are in Washington, D.C., and Columbus, Ohio.

Registered journalists can subscribe to the ACS journalist news portal on EurekAlert! to access embargoed and public science press releases.  For media inquiries, contact newsroom@acs.org.

Note to journalists: Please report that this research was presented at a meeting of the American Chemical Society. ACS does not conduct research, but publishes and publicizes peer-reviewed scientific studies.

Follow us: X, formerly Twitter | Facebook | LinkedIn | Instagram

Title
Functional reflective textile coatings for personal cooling

Abstract
As the effects of climate change become more severe and widespread, maintaining personal thermal homeostasis becomes both necessary for survival and increasingly energy intensive. In principle, advanced textiles and garments can leverage light absorption and/or reflection, in addition to straightforward convection, to heat or cool bodies in extreme temperature conditions. For cooling, in particular, surfaces adept at selectively reflecting or refracting high-energy wavelengths (200nm-2.5um) while transmitting or emitting infrared light (8-13um) boast the ability to maintain cooler body temperatures, even when exposed to direct sunlight and the open sky. Here, we present guiding principles for designing textiles for passive personal cooling via diffuse light reflectance. Biocompatible calcium carbonate and barium sulfate micro/nanoparticles are found to serve as appropriate optical materials for cooling via diffuse reflectance. Finite-difference time domain simulations reveal, surprisingly, that textile coatings containing a polydisperse mixture of CaCO3 and BaSO4 nano/microcrystals provide the highest, broad-spectrum reflection efficiency, as compared to extruded metamaterial fibers containing embedded particles within a polymer matrix. A stepwise process to create polydisperse CaCO3 and BaSO4 nano/microcrystal textile coatings is reported. Through the use of photoinitiated chemical vapor deposition (pICVD), a 5 um thick layer of a hydrophilic polymer polyhydroxyethyleneacrylate (pHEA) was deposited on the fabric substrate. Subsequently, through serial immersion in solutions containing Ca and Ba ions and solutions containing CO3 and SO4 ions, inorganic microcrystals were grown directly on the surface of the fabric. Upon outdoor testing, textiles coated with polydisperse CaCO3 and BaSO4 nano/microcrystals show a cooling ability of 8°C compared to an uncoated sample, achieving a maximum cooling of 4°C below ambient temperature. Washing and durability testing of the coating found no degradation in the material's performance, affirming its resilience and long-term effectiveness. 

END


[Attachments] See images for this press release:
Chalk-based coating creates a cooling fabric Chalk-based coating creates a cooling fabric 2

ELSE PRESS RELEASES FROM THIS DATE:

Pilot study uses recycled glass to grow plants for salsa ingredients

Pilot study uses recycled glass to grow plants for salsa ingredients
2024-08-21
DENVER, Aug. 21, 2024 — Tortilla chips and fresh salsa are tasty in themselves, but they could be even more appealing if you grow the ingredients in a sustainable way. Researchers report that cilantro, bell pepper and jalapeño can be cultivated in recycled glass from discarded, pulverized bottles like those from beer or soda. The pilot study found that partially substituting soil in a planter with recycled glass fragments speeds up plant development and reduces unwanted fungal growth. The researchers will present their results at the fall meeting of the American Chemical Society (ACS). ACS Fall 2024 is ...

MIT engineers’ new theory could improve the design and operation of wind farms

2024-08-21
The blades of propellers and wind turbines are designed based on aerodynamics principles that were first described mathematically more than a century ago. But engineers have long realized that these formulas don’t work in every situation. To compensate, they have added ad hoc “correction factors” based on empirical observations. Now, for the first time, engineers at MIT have developed a comprehensive, physics-based model that accurately represents the airflow around rotors even under extreme conditions, such as when the blades are operating at high forces and speeds, or are angled in certain directions. The model could improve the way rotors themselves ...

Proposed risk factor tool finds heart failure rates are higher among American Indian adults

2024-08-21
Research Highlights: An analysis based on a proposed heart failure risk prediction tool reveals that the incidence of heart failure may be 2- to 3-fold higher among American Indian adults compared to people in other population groups. The risk prediction equation focused on diabetes control and kidney damage indicates that smoking, Type 2 diabetes, high blood pressure, previous heart attack and diabetes-related kidney damage are associated with increased risk of developing heart failure among American Indian adults. The findings suggest a need to develop population-level preventive strategies in American Indian communities, researchers said. Embargoed until 4 a.m. CT/5 ...

Breakthrough in cost-effective production of cultivated meat

Breakthrough in cost-effective production of cultivated meat
2024-08-21
A groundbreaking study demonstrates the first cost-effective method for producing cultivated meat. The study shows that continuous manufacturing addresses the key challenges of scalability and cost, potentially making cultivated meat accessible to everyday consumers and contributing to a more sustainable and ethical food system. In an extraordinary stride for cellular agriculture, Professor Yaakov Nahmias, founder of Believer Meats, and a multidisciplinary team at the Hebrew University of Jerusalem and the cultivated meat industry unveiled a pioneering continuous manufacturing process ...

Marriage strongly associated with optimal health and well-being in men as they age

2024-08-21
A new study that followed over 7,000 Canadians, middle-aged and older, for approximately three years found that married men or men who became married during the study period were twice as likely to age optimally compared to their never-married male peers.  Among women, those who had never married were twice as likely to age optimally compared to married respondents who became widowed or divorced during the study period. Married women did not differ significantly from never-married women with respect to optimal aging. “Little is known about the relationship between marital trajectories in old age and successful aging. Our goal was to see whether different marital trajectories ...

Research shows reducing future global flooding hinges on cutting greenhouse gas emissions

2024-08-21
Pioneering research forecasts worldwide flooding is likely to be significantly worse in future decades if countries fail to meet official pledges to cut carbon emissions. The study, published today and led by experts from the University of Bristol and global water risk intelligence firm Fathom, reveals projections of different types of flooding in various climate change scenarios with unprecedented precision. Through deploying the most comprehensive mapping framework, findings indicate overall global flooding could increase by around half between 2020 and the turn ...

Do gender, ethnicity, and education affect people’s ability to get jobs that fit their interests?

2024-08-21
In a study published in Applied Psychology, researchers investigated the degree to which people can obtain jobs that fit their interests (called vocational interest fit), with the goal of identifying any differences in fit across race/ethnicity, gender, and education. The study included a diverse sample of more than 250,000 American employees. Overall, employees showed moderate positive vocational interest fit with their jobs. There were small gender differences in vocational interest fit favoring men, especially white and Hispanic men, with minimal differences across other race/ethnicity groups. Considerable differences were observed regarding education, ...

Can flexibility help people live longer?

2024-08-21
Flexibility exercises are often included in the exercise regimens of athletes and exercisers. New research in the Scandinavian Journal of Medicine & Science in Sports suggests that levels of flexibility may affect survival in middle-aged individuals. After analyzing data on 3,139 people (66% men) aged 46–65 years, investigators obtained a body flexibility score, termed Flexindex. This score was derived from a combination of the passive range of motion in 20 movements (each scored 0–4) involving 7 different joints, resulting in a score range of 0–80. Flexindex was 35% higher in women compared with men. During an average follow-up ...

Does cognitive behavioral therapy benefit cancer survivors?

2024-08-21
A recent analysis of all relevant published studies reveals clear benefits of Cognitive Behavioral Therapy (CBT) for improving mental health and quality of life in cancer survivors. The findings, which are published in Cancer Medicine, extend CBT’s effects beyond what has long been known in the general population. For the analysis, investigators uncovered 132 clinical trials comparing CBT with controls, including standard therapy, waitlist control, or active/alternative therapy. Across the trials, CBT moderately ...

What’s the best method for extracting edible protein from insects?

2024-08-21
Edible insects are emerging as an alternative protein source that has various benefits compared with conventional animal sources. New research published in the Journal of Food Science compared four different methods for extracting protein from mealworms, which were designated by the European Union as the first insect to be used as a novel food source in 2015. For the research, investigators compared alkali, salt, enzyme, and screw press methods for extracting mealworm protein. Alkali extraction enhanced protein content, enzyme treatment improved nutritional value and antioxidant capacity, and salt-assisted extraction exhibited anti-inflammatory effects. Enzyme and salt treatments ...

LAST 30 PRESS RELEASES:

Reality check: making indoor smartphone-based augmented reality work

Overthinking what you said? It’s your ‘lizard brain’ talking to newer, advanced parts of your brain

Black men — including transit workers — are targets for aggression on public transportation, study shows

Troubling spike in severe pregnancy-related complications for all ages in Illinois

Alcohol use identified by UTHealth Houston researchers as most common predictor of escalated cannabis vaping among youths in Texas

Need a landing pad for helicopter parenting? Frame tasks as learning

New MUSC Hollings Cancer Center research shows how Golgi stress affects T-cells' tumor-fighting ability

#16to365: New resources for year-round activism to end gender-based violence and strengthen bodily autonomy for all

Earliest fish-trapping facility in Central America discovered in Maya lowlands

São Paulo to host School on Disordered Systems

New insights into sleep uncover key mechanisms related to cognitive function

USC announces strategic collaboration with Autobahn Labs to accelerate drug discovery

Detroit health professionals urge the community to act and address the dangers of antimicrobial resistance

3D-printing advance mitigates three defects simultaneously for failure-free metal parts 

Ancient hot water on Mars points to habitable past: Curtin study

In Patagonia, more snow could protect glaciers from melt — but only if we curb greenhouse gas emissions soon

Simplicity is key to understanding and achieving goals

Caste differentiation in ants

Nutrition that aligns with guidelines during pregnancy may be associated with better infant growth outcomes, NIH study finds

New technology points to unexpected uses for snoRNA

Racial and ethnic variation in survival in early-onset colorectal cancer

Disparities by race and urbanicity in online health care facility reviews

Exploring factors affecting workers' acquisition of exercise habits using machine learning approaches

Nano-patterned copper oxide sensor for ultra-low hydrogen detection

Maintaining bridge safer; Digital sensing-based monitoring system

A novel approach for the composition design of high-entropy fluorite oxides with low thermal conductivity

A groundbreaking new approach to treating chronic abdominal pain

ECOG-ACRIN appoints seven researchers to scientific committee leadership positions

New model of neuronal circuit provides insight on eye movement

Cooking up a breakthrough: Penn engineers refine lipid nanoparticles for better mRNA therapies

[Press-News.org] Chalk-based coating creates a cooling fabric