Vacuum Drying Temperature-Sensitive Materials Effectively

Tips for vacuum drying heat sensitive materials with SNAP

Decreasing the drying time of heat-sensitive products can be challenging. Temperature-responsive polymers are polymers that exhibit a drastic and discontinuous change of their physical properties with temperature. The need for drying polymers can be found in many different industries including: additive manufacturing, life sciences, tissue engineering, liquid chromatography, drug delivery, and research and development. Other heat sensitive materials include fruits and vegetables and other botanicals. Vacuum drying is an ideal method for drying thermal and/or oxygen sensitive materials due to the advantage of removing moisture at low temperatures and minimizing the possibility of oxidation reactions. In addition, vacuum drying has the added benefits of a faster drying rate and can be conducted in an oxygen-deficient processing environment.

Utilizing a vacuum oven with automated temperature control allows you to keep your process at precise temperature that maximizes the drying time but avoids damaging the product. Some polymers are more polar than others and bind more strongly to water molecules thus the higher necessary temperatures to dry the polymer. By putting the polymer in a vacuum the user will be able to dry the molecules quicker using less energy.

Here is an example of some vacuum pressure/ temperature combinations that could utilized:

Water	212F	760 Torr
	113F	80 Torr
	100F	56 Torr
	73F	25 Torr
	45F	10 Torr

Some of the most common vacuum drying ovens have digital temperature control, but manual vacuum control valves. At DigiVac, we are all about making vacuum science simple. Adding a vacuum controller to your oven will take you that much closer to full optimization of your process. As you can see from the table, the temperature is kept constant, and the vacuum pressure stays within the rough vacuum range (greater than 1 Torr). This is much easier to do when you add a vacuum controller to your system to regulate vacuum effectively.

Our automated vacuum controllers have integrated sensors that have control ranges of 1 torr up to 760 Torr. Examples of these are the Vapor Pressure Controller and the SNAP. For freeze dryers, you may need lower pressures with a control range below 1 Torr, and we have solutions for that too.

Both of these controllers are made from corrosive resistant high quality stainless steel wetted materials. The VPC offers precise vacuum control by controlling within an upper and lower set-point and is a good option for up to 20 Liters or 3 cubic foot chamber. For larger chambers from 20 liters and above, SNAP has the added benefit of higher throughput delivered by the Digivac proprietary Dinamo valve which offers proportional bleed (for evacuate and purge cycles) and proportional throttle control. The SNAP also has onboard RAMP control and programmable time vs. pressure recipes.

By optimizing your process with an automated vacuum controller you can create a more efficient vacuum drying process. Interested in having your own SNAP click here!

Don’t feel like reading, watch the video demo below!

DigiVac offers a variety of Vacuum controllers and Vacuum Ovens to support your vacuum drying needs. Shop our collections to help automate your process!