Cool Cube™ Lab Freezer temperature regulating panels contain phase change material (PCM) that is nontoxic, biodegradable and has similar characteristics to that of water. However unlike water, freezing points are custom formulated to maximize the hold time within specific temperature parameters.
Lab Freezer PCM turns solid when its temperature is below -21.5°C/-6.7°F (unlike water which has a freezing point of 0°C/32°F). When using solid, Lab Freezer PCM panels in the Cool Cube™, packed out product will stay frozen in warm/hot conditions for an extended period of time.
About Lab Freezer PCM (Phase Change Material)
PCM absorbs and releases thermal energy during the process of melting and freezing. When solid PCM melts, it absorbs the heat from the environment, yet its temperature stays at the melting point until totally liquid. Conversely, when liquid PCM freezes, it absorbs the cold from the environment yet stays at its temperature until totally solid. Therefore, PCM an ideal, passive solution for a variety of applications that require temperature control. The most common PCM is water, which has a melting point of 0 °C (32 °F). When solid, ice/water maintains a temperature of 0 °C until it turns completely liquid. So, in essence, the 0 °C melting point makes it unsafe for most frozen temperature-sensitive applications.
Cool Cube™ Lab Freezer PCM has a melting point of -21.5 °C/-6.7 °F. When the PCM is solid, a panel helps the Cool Cube™ stay cool (about -21 °C) in warm/hot environments. It’s right around that -21.5 °C/-6.7 °F where a PCM panel’s temperature plateaus for a while during the warming up and/or cooling down processes.
CLICK & PRINT DOWNLOADS (PDF)
Prep Method A: Ultra-Low Freezer Prep to keep product frozen
2.1 Lay panels flat in an ultra-low freezer until all the PCM (phase change material inside the panel) turns solid. At -25°C/-13°F the PCM will solidify in a day or two.*
- * If the freezer temperature is ever warmer than -25°C, PCM may not get completely solid (due to the possibility of supercooling). If panels are stored within the temperature parameters of the product but the PCM is liquid, panels may be used but the hold time will decrease.
2.2 Shake panels to verify the PCM is solid. If there is liquid, restart at step 2.1 to ensure the longest hold time. Using liquid PCM or panels with a solid/liquid combination decreases the hold time.
Prep Method B: Dry Ice Prep to keep product frozen
2.1 Pack out cooler with dry ice until the PCM (phase change material inside the panel) panels become solid. The more dry ice, the faster the PCM will solidify.*
- * Time varies dependent on the starting temperature of the panels, size of panels, and amount of dry ice used. CAUTION: Dry ice has a surface temperature of -78.5°C/-109.3°F, so handle with care.
2.2 (Optional) If product to be packed out cannot withstand an initial -70°C temperature, transfer panels into a standard freezer at least 3 hours before use. Panels may be stored in the freezer until needed for assembly or the PCM melts.
If a freezer maintains -23°C or below, the PCM within the panels will not melt (melting point is -21.5°C), keeping the PCM solid indefinitely until pack-out. If the freezer maintains -21.5°C or above, periodically check for melting and restart at step 2.1 to ensure the longest hold time.
2.3 Shake panels to verify the PCM is solid. If there is liquid, restart at step 2.1 to ensure the longest hold time. Using liquid PCM or panels with a solid/liquid combination decreases the hold time.
Prep Method C: Standard Freezer Prep to keep product frozen
Store panels in a standard freezer (turned down to its lowest setting) for a minimum of 24 hours before use. Unless the freezer is always below -23°C, the PCM (phase change material inside the panel) will never turn completely solid, but short-term use is still possible.*
- * Although PCM is liquid, it is at the temperature of storage environment after 3 hours. For instance, panels stored in a -18°C freezer are at -18°C even PCM is liquid. Assembling the Cool Cube™ with this additional thermal mass will keep product frozen, just for a shorter amount of time than the lab-validated results.
Shake panels to check the state of the PCM (phase change material inside the panel).
- If liquid…panel is at the freezer temp but above -20°C; anticipate shorter hold times.
- If solid…panel is at the freezer temp but below -23°C; ideal for maximum hold times.
- If solid/liquid combination…panel is at the freezer temp between -23 and -20°C; monitor longer use periods.
Phase change materials (PCMs) are materials that absorb and release thermal energy during the process of melting and freezing. When a PCM melts, it absorbs the heat from the environment, yet its temperature stays at the melting point until totally liquid. Conversely, when a PCM freezes, it absorbs the cold from the environment, yet stays at its temperature until totally solid. This makes PCM an ideal, passive solution for a variety of applications that require temperature control. The most common PCM is water/ice. Ice is an excellent PCM for maintaining temperatures at 0°C. But water’s freezing point is fixed at 0°C (32°F), which makes it unsuitable for most temperature sensitive applications.
Cool Cube™ PCMs offer custom temperature holds based on their melting point. The PCM inside Lab Freezer panels has a melting point of
[wpfilebase tag=file id=433/]
- Always prep the PCM panels before use according to one of the described methods provided by VeriCor.
- Ensure all components are clean and free of damage.
- During prep, enable ample air flow around all panel sides (use spacers or racks).
- Lay panels flat when “freezing”.
- Freeze/melting times vary depending on number of panels being prepped and equipment specifications being used. Assemble using all six panels for maximum hold time.
- Using less panels does not change the holding temperature but does decrease hold time.
- Panels are reusable (10,000+ cycles). (End-of-life disposal: panels use a plastic #2, typically recycled by businesses/communities; PCM is nontoxic and readily biodegradable.)
- Use a calibrated data logger or other temperature monitoring device to observe internal temperature.
- Avoid unnecessary opening of the Cool Cube™ after loading payload. Opening of the Cool Cube™ will decrease hold time.
- An infrared temperature thermometer can assist in ensuring the panels reach a safe pack-out temperature (good for finding out the approximate temperature of each panel).
- Further the temps are away from the melting point, the quicker PCM will change states.