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Glacier Tek LLC of Minneapolis has incorporated flexible PCM microspheres in the cooling packs used in its Flex Vest line of cooling vests.
The cooling packs, redesigned for improved comfort and performance, feature a soft, durable nylon shell. They reach a flexible state more quickly and feel colder than the previous packs.
The Flex Vest is designed to maintain a comfortable microclimate of 18 degrees C for up to 2.5 hours. The new packs can be recharged in about 30 minutes in ice water or two hours in a refrigerator. But they are most effective when fully solidified in a freezer, which takes about an hour. The cooling packs weigh about 164 grams each and fit into 12 pockets inside the vest.
The novel cooling material, developed by PureTemp LLC of Minneapolis, is composed of a biobased phased change material. It is similar to the material used in the Glacier Tek therapy cooling packs introduced at the American College of Sports Medicine trade show in Orlando in May.
“PureTemp is excited to bring this shape-stabilized PCM format to the market,” said Chris Servais, vice president of operations at PureTemp. “Glacier Tek has capitalized on its unique and improved characteristics.”
U.S. patent application 20190211171 (assignees Dow Global Technologies LLC, Midland, Mich., and Rohm and Haas Co., Collegeville, Penn.):“A coated viscoelastic polyurethane foam includes a viscoelastic polyurethane foam having the coating thereon, the viscoelastic polyurethane foam having a resiliency of less than or equal to 20% as measured according to ASTM D3574, and a coating material on and embedded within the viscoelastic polyurethane foam, the coating material including an aqueous polymer emulsion and an encapsulated phase change material.”
U.S. patent application 20190210790 (applicant Cold Chain Technologies Inc., Franklin, Mass.):
“Shipping system for storing and/or transporting temperature-sensitive materials. In one embodiment, the system includes an outer box having four side walls, bottom closure flaps, and top closure flaps. A vacuum insulated panel (VIP) is detachably coupled to one of the top closure flaps and is removably covered by a cover. An insulation unit is removably positioned within the outer box, the insulation unit including a plurality of VIPs arranged to define a cavity bounded by a bottom wall and four side walls. A disposable liner is removably mounted on the insulation unit. The liner may be a thermoformed sheet and may cover the interior and top surfaces of the insulation unit.”
U.S. patent application 20190210743 (applicant Planet Labs Inc., San Francisco, Calif):
“An apparatus attached to a feature to be deployed on a satellite, the apparatus comprising: a first material having an impedance; a second material coupled to the first material configured to provide a current or voltage to the first material causing the first material to generate heat based on the impedance after a launch process of a launch vehicle carrying the satellite has completed; a third material configured to change state at a transition temperature, wherein: a release mechanism is coupled to the third material and holds the feature in an undeployed position on the satellite, the heat generated by the first material causes the third material to change state from a first state to a second state when the transition temperature range is reached, and the release mechanism is released from the third material when the third material is in the second state to deploy the feature from the satellite after the launch process has completed. … The restraint system includes a phase-change restraint material that changes state at a transition temperature. For example, when the material is below the temperature, the structure of the material is a solid state, such as a ‘glassy’ state that reliably holds, binds, and restrains the deployment of the feature. However, when the material goes above the temperature, the material experiences a phase change to an amorphous material and the restraint system is released from being attached to a release mechanism to deploy the feature.”
For our full list of recent academic research, see puretemp.com/academic. Here are highlights from the past week:From Trends in Food Science & Technology:
• Micro/nano-encapsulated phase change materials (PCMs) as emerging materials for the food industry
From Solar Energy Materials and Solar Cells:
• A foamed cement blocks with paraffin/expanded graphite composite phase change solar thermal absorption material
• Solvent-free preparation of bio-based polyethylene glycol/wood flour composites as novel shape-stabilized phase change materials for solar thermal energy storage
• Spray-graphitization as a protection method against corrosion by molten nitrate salts and molten salts based nanofluids for thermal energy storage applications
• Preparation and characterization of microencapsulated phase change materials containing inorganic hydrated salt with silica shell for thermal energy storage
• Enhancing thermal conductivity of paraffin wax 53–57 °C using expanded graphite
From Solar Energy:
• Simultaneous charging and discharging of phase change materials: Development of correlation for liquid fraction
From Energy and Buildings:
• Numerical study of the electrical load shift capability of a ground source heat pump system with phase change thermal storage
From International Conference on Materials, Environment, Mechanical and Industrial Systems:
• Simulation-based analysis of the use of PCM and shading devices to improve the thermal comfort in buildings
From Applied Thermal Engineering:
• Experimental study of a pilot-scale fin-and-tube phase change material storage
• On-demand Intermittent Ice Slurry Generation for Subzero Cold Thermal Energy Storage: Numerical Simulation and Performance Analysis
• Atomistic modelling of water transport and adsorption mechanisms in silicoaluminophosphate for thermal energy storage
From Clima 2019, 13th REHVA World Congress:
• Experimental comparison of radiant ceiling panels and ceiling panels containing phase change material (PCM)
From Journal of Energy Storage:
• Review of stability and thermal conductivity enhancements for salt hydrates
• Characterisation of promising phase change materials for high temperature thermal energy storage
From Journal of Cleaner Production:
• Self-assembly of 3D-graphite block infiltrated phase change materials with increased thermal conductivity
From Sustainable Cities and Society:
• Thermal Performance Difference of Phase Change Energy Storage Units Based on Tubular Macro-encapsulation
From Renewable and Sustainable Energy Reviews:
• State-of-technology review of water-based closed seasonal thermal energy storage systems
From Applied Energy:
• Thermal energy storage in district heating and cooling systems: A review
• Fabrication and Characterization of Novel Shape-Stabilized Phase Change Materials Based on P(TDA-co-HDA)/GO Composites
More than 1,480 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 Derall Riley, a mechanical engineering undergrad at Arizona State University, Tempe, Arizona; and Raheleh Avanmardi, research assistant at Technische Universität Kaiserslautern, Germany.