SIENOX Planetary Vacuum Mixing & Defoaming Mixer adopts an impeller-free non-contact design. It mixes materials through planetary revolution and rotation movement, and completes mixing and defoaming simultaneously with a vacuum system. The standard vacuum level is -98 kPa. SIE-MIX60 handles 0–300 mL per batch, while SIE-MIX1000plus handles 0–1000 mL per batch. It solves the conflicting problem of high-viscosity materials: uneven mixing and incomplete bubble removal.

What is a planetary vacuum mixing and defoaming mixer? How does it differ from centrifugal defoaming and blade stirring?.png

1. Definition and Working Principle

The operation of a planetary vacuum mixing and defoaming mixer consists of three synchronized actions:

  1. Revolution: The material cup revolves around the main spindle of the equipment, turning the whole material mass and ensuring uniform force distribution across all zones inside the cup.

  2. Rotation: The material cup spins around its own axis at the same time, disturbing the internal flow field and preventing the material from rotating passively together with the cup.

  3. Vacuuming: The sealed chamber is evacuated to a standard vacuum of -98 kPa (-100 kPa optional). Reduced pressure makes internal bubbles expand, rise and rupture under pressure difference.

Mixing and defoaming are finished in one single cycle. The whole process is impeller-free and non-contact — materials only touch the inner wall of the cup. This is the fundamental difference from traditional blade stirring.

2. Comparison of Three Defoaming Methods

Comparison Item

Blade Stirring (Atmospheric / Vacuum)

Centrifugal Defoaming

Planetary Vacuum Mixing & Defoaming

Mixing Method

Shearing by immersed blades

Bubbles separated by centrifugal force, limited mixing capacity

Planetary revolution + rotation, non-contact

Material Contact

Contact

Non-contact

Non-contact (impeller-free, material only touches cup wall)

Risk of Metal Contamination / Shear Damage

Shear exists; blade wear may introduce foreign particles

No shearing

Impeller-free, no metal contamination risk

Mixing Dead Zone

Dead zones near blade root and tank wall

No mixing action, risk of material stratification

Material tumbles with planetary motion, no dead zone

Cleaning

Complex blade structure, risk of residue

Simple structure

No internal blades, no cleaning residue

Applicable Viscosity

Wide range

More effective for low & medium viscosity

Outstanding for medium & high viscosity (subject to actual test)

Summary: Blade stirring works by "shearing", centrifugal defoaming by "throwing bubbles out", and planetary vacuum mixing & defoaming completes mixing and defoaming simultaneously via "tumbling + spinning + vacuum evacuation".

3. Typical Process Workflow (Thermal Conductive Potting Compound as Example)

The viscosity and duration data below are typical reference values, subject to on-site test results.

Background: For electronic potting applications, two-component thermal conductive potting compound features high solid content and high viscosity. Manual stirring leaves internal bubbles, which cause shrinkage cavities after curing.

Difficulty: Bubbles rise extremely slowly under high viscosity; static defoaming under atmospheric pressure is impractical. Thermal conductive fillers in potting compound are shear-sensitive; blade stirring may damage filler dispersion and introduce metal contamination from blade wear.

Selection Reason: This scenario requires one-step mixing and defoaming, non-contact impeller-free design and high vacuum capability — exactly the strengths of planetary vacuum mixing and defoaming mixers.

Process Steps:

  1. Load proportioned material into the mixing cup, filling volume within the recommended range (refer to equipment manual).

  2. Secure the cup, check sealing gasket, then start vacuum pump and pull down to target vacuum (standard -98 kPa, adjust vacuum level according to material).

  3. Set revolution and rotation speed, start at low speed and ramp up after observing material tumbling (SIE-MIX60 max 3000 RPM, SIE-MIX1000plus max 2000 RPM, both stepless adjustable).

  4. Run under vacuum + rotation for a holding period (typically 3–10 minutes, determined by viscosity and loading volume).

  5. Release vacuum slowly to atmospheric pressure, take out material and inspect bubble residue. Repeat the cycle if needed.

Comparison: Before treatment — visible bubbles on surface and internal voids in samples; After treatment — smooth surface and no obvious internal bubbles. Final defoaming performance heavily depends on formulation; sample testing is recommended.

4. Key Parameters of Main SIENOX Models

Parameter

SIE-MIX60 (Gear Drive)

SIE-MIX80 (Belt Drive)

SIE-MIX1000plus

Batch Capacity

0–300 mL

0–300 mL

0–1000 mL

Rotation Speed

0–3000 RPM, stepless adjustable

0–3000 RPM, stepless adjustable

100–2000 RPM, stepless adjustable

Vacuum Level

-98 kPa standard, -100 kPa optional

-98 kPa standard, -100 kPa optional

-98 kPa standard, -100 kPa optional

Transmission Feature

Gear drive, mature structure

Belt drive, lower noise

Dual cup station, for pilot & small production

Overall Dimension

510×430×500 mm

510×430×500 mm

820×610×760 mm

Temperature Control

Optional customized module, not standard

Same as left

Optional customized module (heating / cooling available)

SIE-MIX60 and SIE-MIX80 share identical core parameters within the 300 mL range; the difference lies in transmission. SIE-MIX80 with belt drive is preferred for noise-sensitive laboratories.

5. Common Misconceptions

  • Misconception 1: Higher vacuum is always better. The standard -98 kPa (-100 kPa optional) is the upper limit of equipment capability. Vacuum should be tuned by material; low-viscosity liquids may foam violently and overflow at extreme vacuum.

  • Misconception 2: Maximum speed gives highest efficiency. Excessively high speed may cause obvious temperature rise for certain materials. Temperature control is optional, verify process demand before adding this module.

  • Misconception 3: Batch capacity equals cup volume. Valid working capacity follows the rated batch range (0–300 mL for SIE-MIX60 / SIE-MIX80, 0–1000 mL for SIE-MIX1000plus), with reserved space for foaming.

FAQ: 5 Frequently Asked Questions about Planetary Vacuum Mixing & Defoaming Mixers

Q1: How to choose between planetary vacuum mixer and centrifugal defoamer? Choose planetary type when high mixing performance and high viscosity are required; centrifugal type works for simple bubble removal with low mixing demand. They are not mutually exclusive.

Q2: What vacuum level can SIENOX defoamers reach? SIE-MIX60, SIE-MIX80 and SIE-MIX1000plus offer standard -98 kPa, optional -100 kPa. Process vacuum is adjusted according to material characteristics.

Q3: Will it introduce metal contamination like blade stirring? The planetary design is impeller-free and non-contact. Materials only touch the cup wall, eliminating contamination from blade wear.

Q4: Which model for small-batch multi-formula lab work? 300 mL grade SIE-MIX60 (gear drive) or SIE-MIX80 (belt drive, quieter). Free sample testing from SIENOX is available for verification before purchase.

Q5: Does the defoamer come with temperature control? Temperature control is an optional customized module instead of standard configuration. Sample testing is recommended to confirm actual process demand.