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A novel phase change material developed by PureTemp LLC of Minneapolis is the key component of a new flexible therapy pack introduced at the American College of Sports Medicine conference in Orlando, Fla., last month.
The flexible PCM microspheres have a melt point of 18 degrees C and remain pliable when frozen. The flexible GlacierPacks, developed by Glacier Tek LLC of Minneapolis, are designed to provide targeted cooling relief for bruises, muscle strains, headaches and more. The patent-pending packs can be recharged in ice water in about an hour, hold their target temperature of 18 C for more than two hours and can be reused indefinitely.
The packs can be applied directly to skin without damaging tissue or causing discomfort. They can be used safely and effectively for longer periods than traditional ice packs or cold water immersion (CWI) treatments.
In research led by Dr. Malachy P. McHugh and Susan Y. Kwiecien of the Nicholas Institute of Sports Medicine and Athletic Trauma in New York, packs filled with PureTemp’s biobased phase change material have been shown to provide a practical way to deliver prolonged post-exercise cooling and thereby accelerate muscle recovery.
A 2019 study, “Accelerated Recovery of Muscle Function in Baseball Pitchers Using Post-Game Phase Change Material Cooling,” set out to examine the effectiveness of post-game PCM cooling on strength recovery in pitchers. Based on prior research (Kwiecien et al 2018 and Clifford et al 2018), it was hypothesized that PCM cooling would accelerate recovery. The flexible cooling packs were applied to the elbows and forearms of college pitchers after each had thrown 45 pitches. Pitchers in a control group received no PCM cooling treatment. The strength, soreness and creatine kinase levels of the athletes were then measured to gauge the effectiveness of the PCM cooling. CK is an enzyme released into the blood at elevated levels when there is muscle damage.
The researchers concluded that prolonged PCM cooling accelerated recovery of strength but did not affect soreness or CK levels. “The effect of PCM cooling of the medial elbow and forearm on grip strength recovery is very encouraging considering the role the wrist flexors play in dynamic stability of the elbow,” the researchers wrote.
“Can you believe it? A PCM that remains flexible when fully charged!” said RoxAnne Best, president of PureTemp and Glacier Tek. “I am really proud of our team for their commitment to bringing this technology to market. The consumer application possibilities are endless.”
The therapy packs are available on Amazon and on the Glacier Tek website. A set of six packs retails for $179. Contact Glacier Tek to inquire about samples, volume discounts and custom configurations.
THERMAL ENERGY STORAGE
8 Viking Cold Solutions systems installed in Massachusetts
Viking Cold Solutions has completed the installation of eight thermal energy storage systems as part of a utility-backed demand management program in Massachusetts. The Houston company says its PCM-based system, designed for use in cold storage facilities, stores enough energy to cycle off refrigeration for up to 13 hours per day and reduce energy consumption by more than 25 percent.
U.S. patent application 20190178534 (inventor Nico Ros, Riehen, Switzerland):
“In a transport container for transporting temperature-sensitive transport goods comprising a chamber for receiving the transport goods, a casing enclosing the chamber and at least one cooling element for temperature control of the chamber, the cooling element comprises an evaporation element with a cooling surface and a desiccant for receiving coolant evaporated in the evaporation element. The transport container further comprises a latent heat accumulator that communicates with the chamber for heat exchange. … In a preferred embodiment, in which the transport goods are to be kept in the chamber at a temperature range of 2-8° C., the latent heat accumulator has a phase transition temperature of approx. 4-6° C.”
U.S. patent application 20190175395 (applicant RecensMedical Inc., Ulsan, South Korea):
“The present disclosure provides a device and a method for cooling living tissues for a medical purpose and other purposes. The cooling device comprises: a container configured to accommodate a cooling medium and thermally coupled with the cooling medium by directly contacting the cooling medium; a cooling generator configured to be thermally coupled with the container by a direct contact and thereby to provide cooling energy to the cooling medium; and a heat sink dissipating heat from the cooling generator. … [The] heat transfer medium  may comprise a heat pipe or a vapor chamber and may include a pipe body and phase change material (PCM) provided inside the pipe body. The pipe body may be made of material having the high thermal conductivity so as to effectively transfer the heat from the cooling generating unit that is in contact with the heat transferring medium to the PCM therein.”
U.S. patent application 20190177224 (applicant Université de Cergy-Pontoise, Cergy, France):
“A method for manufacturing a solid-solid organic phase-change material made of polyurethane, said method comprising: a single step (i) of synthesis by mixing and reacting a liquid polyethylene glycol, a crosslinking agent, and a liquid polyisocyanate, combined by mechanical agitation at a first controlled temperature, in an enclosure in order to obtain the liquid polyurethane, a step (ii) of curing the liquid polyurethane at a second controlled temperature in order to solidify the polyurethane, the synthesis step (i) being carried out in the absence of a solvent.”
For our full list of recent academic research, see puretemp.com/academic. Here are highlights from the past week:From Solar Energy:
• Effectiveness of phase change materials for improving the resiliency of residential buildings to extreme thermal conditions
From Energy Conversion and Management:
• Analysis and design of air ventilated building integrated photovoltaic (BIPV) system incorporating phase change materials
• Experimental and numerical study on a novel hybrid battery thermal management system integrated forced-air convection and phase change material
From Applied Thermal Engineering:
• Thermal Performance of Electrospun Core-Shell Phase Change Fibrous layers at Simulated Body Conditions
From Applied Engineering:
• Phase change material blind system for double skin façade integration: System development and thermal performance evaluation
From Building and Environment:
• Reduced-scale experiments on the thermal performance of phase change material wallboard in different climate conditions
From Renewable Energy:
• Analysis of a laboratory scale thermal energy accumulator using two-phases heterogeneous paraffin wax-water mixtures
From Thermochimica Acta:
• Nano-inclusion aided thermal conductivity enhancement in palmitic acid/di-methyl formamide phase change material for latent heat thermal energy storage
From Journal of Manufacturing Processes:
• Experimental investigation of phase change materials fabricated using selective laser sintering additive manufacturing
From International Journal of Heat and Mass Transfer:
• Cyclic characteristics of water thermocline storage tank with encapsulated PCM packed bed
From Journal of Building Engineering:
• Thermal behaviour of wallboard incorporating a binary mixture as a phase change material
From Composites Part B: Engineering:
• Effects of aging on asphalt binders modified with microencapsulated phase change material
From Chemistry Select:
• Experimental Study of the Thermal Properties of Microencapsulated Palmitic Acid Composites with CuCO3 Shell as Thermal Energy Storage Materials
From Fire Safety Journal:
• Fire resistance of light gauge steel framed wall systems lined with PCM-plasterboards
From ACS Applied Nano Materials:
• Size-tunable Alumina-encapsulated Sn-based Phase Change Materials for Thermal Energy Storage
More than 1,475 people have joined a LinkedIn group devoted to the discussion of phase change material and thermal energy storage. The Phase Change Matters group is an interactive complement to the award-winning blog and newsletter of the same name.
You are invited to join the group and connect with PCM and TES experts from around the world. This week we welcome Egil Arne Skare, senior project engineer at Østensjø Rederi, Karmsund, Norway; Guy Manor, bachelor of science (2018) at Afeka Tel Aviv Academic College of Engineering, Israel; Amit Rai, postdoctoral research associate at Oak Ridge National Laboratory, Oak Ridge, Tenn.; and Jill Byrne, RN surgery, Cleveland Clinic, Cleveland, Ohio.