What is VCM Technology?

More than three letters.

VCM (Vacuum Compression Molding) allows the mg-to-g scale screening of new formulations for hot-melt extrusion. VCM is a process that transforms thermoplastic materials into homogeneous specimens without altering the source materials’ characteristics due to degradation.

VCM Tool

Perfect samples


or extrudates, flakes etc.

Vacuum Compression Molding by MeltPrep


or powder etc.

How does it work?

In three steps.

The desired amount of materials is filled into the VCM Tool. Vacuum is applied, compacting the powder as well as preventing bubbles.

Step 1 : Vacuum Compaction

Rapid melting is achieved by heating the VCM Tool on a preheated hot plate. Particles fuse together to create a homogenous melt.

Step 2 : Melting 

Perfect samples

Rapid cooling of the VCM Tool is

obtained by convection and conduction
on a separate cooling unit solidifying the sample.

Step 3 : Cooling

Vacuum Compression Molding by MeltPrep

What are the innovations?

Simplicity at its best.

The VCM sample chamber is fully PTFE-lined and yet adaptable in volume. Thanks to the arrangement of the foils, two key innovations are guaranteed. #1 adaptable sample chamber: It follows the natural material behavior during sample preparation. Density changes during compaction, melting and solidifying are compensated and defined sample geometries are obtained.


or flakes etc.




Compaction pressure


Geometrically defined sample,

no voids or bubbles

Key innovation #1: Adaptable sample chamber

Key innovation #2: Peelable sample chamber



#2 peelable sample chamber: The separation foils are simply peeled off after the preparation process. No tedious cleaning is required. The chamber has no dead zones enabling lossless sample preparation. After the insertion of new foils, the equipment is ready for the next preparation cycle. The foils can be reused multiple times making the process even more cost efficient.

Vacuum Compression Molding by MeltPrep

How much material do I need?

Just enough to shape your sample.



The VCM Process holds the balance between input and output material. It’s the first lossless approach to melt samples into a defined shape without air inclusions. With 1 gram of powder, you will obtain a cylindrical sample of 1 gram with a defined shape.

Ø 2 mm

up to 10 mm length

1 - 50 mg required

We understand that for some applications, 1 gram might already be a very high quantity. That’s why we have downsized our VCM Technology to dimensions as small as 2 mm in diameter. 2 mm rods can be produced with heights of 0.1 mm and 10 mm enabling screenings, accurate material characterization -starting at the low mg-range.

What about mixing?

Empower diffusion.

It’s important to obtain a homogeneous starting material in the small micrometre range to empower diffusive mixing.


If you work with heterogeneous materials at large particle sizes and process it via VCM, you will obtain a heterogeneous sample. VCM is not applying any mechanical mixing inside the Chamber. To illustrate this, we have chosen to fuse multi-colored pellets in the mm-size range with VCM. They are squeezed and melted together, forming a solid disc without air inclusions but the individual pellets with a sharp interface are still visible.  


Pellets (length scale = mm range)

VCM Processing

One solid disc,

individual pellets visible.


Empowering diffusion is key to obtain a homogeneous sample out of heterogeneous starting materials. We can reduce the particles’ size by starting with a physical powder mixture. After the VCM processing, the result is better than the previous one, but some agglomerates and inclusions are not completely dissolved. This might be due to insufficient mixing or too large particle sizes in general.






VCM Processing

Inhomogenous sample with API crystals.

Empowering diffusion

To  obtain diffusive mixing it’s important to have a starting material which is homogeneous in the small micrometer range. Our customers usually apply a milling step, preferably under cryogenic conditions. After VCM processing the result will be a homogeneous and defined sample that has properties comparable to extruded formulations.

Cryo Milling


Powder (HPMCAS)


Route 1: Milling

Route 2: Solvent casting


Mixing Powder [5g] and tip of spatula with 100 ml Ethanol.

Let the solution evaporate until a thin layer remains

Homogenous sample.

Homogenous sample.

Another way to empower diffusion is particle dissolution via solvent casting. We can use suitable solvents (ethanol, acetone), let the particles dissolve in it and pour the solution on a Petri Dish. Afterwards, we let the solvent evaporate until we obtain a thin layer of our materials. The layer is peeled off from the Petri Dish and transferred to the VCM Tool, from which a homogenous sample is obtained after processing.

Vacuum Compression Molding by MeltPrep
Vacuum Compression Molding by MeltPrep
VCM Customer
VCM Customer

Who are our customers?


Check out our testimonial page and see yourself what our customers say about our technology.

Vacuum Compression Molding by MeltPrep

Do you prefer a video?

Just one click.

VCM technology enables lossless and rapid production of solid samples from powder by performing fusion under vacuum, allowing milligram to gram scale screening. Watch the video to get all the insights!

Vacuum Compression Molding by MeltPrep

What are the benefits?


The key innovations change the rules. New possibilities simplify daily lab routines and open up new doors in development. Improved sample quality may reveal new insights into material characteristics. The shortcuts allow you to concentrate on more important tasks.

Rapid & straightforward process

The VCM process can be used to combine several VCM samples to one merged multilayer sample easily. Multilayer structures result in different functional benefits (e.g. diffusion barrier).




based approach

The process is robust and easy to operate. The temperature is the key process parameter. A sample is usually produced in less than 10 minutes without tedious process development.

Multilayered structures prototyping

Lossless sample preparation

The VCM Tool is the first device to enable lossless sample preparation. Thanks to the thoughtful design of the sample chamber, there are no dead zones.

Air inclusions are prevented using vacuum during the entire sample preparation process. Even micronized powders melt homogeneously to form solid specimens with defined geometries.

Homogeneous with defined geometry







Material A

Material B

Co-extrusion die


Co-extruded strand

Minimal cleaning effort

The separation foils form the sample chamber. Replacing the foils saves you valuable development time as cleaning is reduced to a minimum.


Vacuum Compression Molding by MeltPrep

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