Phase Change Materials (PCM) Shipping
Cold-Chain
Supplies
PCMs change phases at a specific temperature and are often used to keep substances cold but not frozen
For example, if you have a substance that needs to remain at exactly 3°C or below, there is a PCM specifically formulated to meet your needs.
Shipping with Phase Change Materials
Advantages:
Unlike dry ice or wet ice, PCMs can be refrozen and reused
PCMs maintain a very specific temperature range that is often cold, but not frozen
PCMs work in both directions keeping your substance from getting too cold or too hot
Disadvantages:
PCMs need to be “pre-conditioned”, which is a very specific process that can take hours to freeze or refrigerate them to the right temperature
Adding more PCMs doesn’t linearly add onto the amount of time a package can be shipped/stored. If 4 gel packs are needed to maintain a certain temperature for 3 days while shipping, 8 gel packs would not give you 6 days with the same result
Dry ice is readily available and logistically easier for a recipient to ship with versus the time and resources required to re-freeze a PCM
Shipping with Dry and Wet Ice

At a specific temperature, every substance undergoes a change in phase. For instance, water changes from a solid to a liquid state when its temperature reaches 0°C (32 F).
When a substance reaches its phase change temperature, it absorbs a significant amount of heat at a constant temperature until it completely melts. This property makes ice an effective coolant for anything that needs to be kept at or below 0°C, as long as the packaging can contain the liquid water.
Another substance that changes phase at a specific temperature is solid carbon dioxide, commonly known as dry ice. It changes phase at a temperature of -78°C and is used to keep substances frozen at or below -78°C. An added advantage of dry ice is that it sublimates into a gas, leaving no liquid behind that could potentially harm the substance or its packaging.
Each shipment is unique and Mercury’s expert team provides a customized solution to meet your specific needs. We also sell cold chain supplies such as PCMs, dry ice and validated thermal shippers.
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