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Introducing the high viscosity mixer that easily processes viscous pastes and Slurries Other Mixers Can't
What is Viscosity?
Viscosity is a measure of how resistant a fluid is to flow and is measured in centipoise (cP) and is one of the properties that influences how easily a mixture can achieve homogeneity.
Low viscosity materials - such as water and other liquids, have a lower resistance and flow more rapidly. Water has a viscosity of 1 cP.
High viscosity materials - such as honey or tar resist deformation and flow more slowly. Honey has a viscosity ranging from 2,000 to 10,000 cP. Some highly viscous materials have a viscosity of hundreds of millions centipoise - approaching what appears to be and behave much like a solid. Pastes, slurries and highly viscous mixes are made up of solids in a liquid matrix.
Why is High Viscosity Mixing a Problem?
High viscosity mixing is one of the most challenging problems in industrial processing. Whether you're working with electrode pastes, pharmaceutical ointments, ceramic slurries, adhesives, or filled polymer compounds, the same frustrating pattern tends to repeat: long processing times, poor uniformity, damaged materials, and a scale-up process that forces you to start over from scratch.
Conventional mixing technology has been trying to solve this problem for decades. It hasn't. Not completely.
ResonantAcoustic® Mixing (RAM) takes a fundamentally different approach — and the results speak for themselves.
How RAM Works and Why It's Different
ResonantAcoustic® Mixing uses low-frequency, high-intensity acoustic energy — sound — to mix materials rather than mechanical agitation. A precision transducer converts electrical energy into resonant acoustic waves that are transmitted through the mixing vessel and into the material itself.
The result is something no rotating blade or paddle can produce: simultaneous three-dimensional movement of every particle in the batch, at the same time.
In a conventional mixer, movement propagates outward from the mixing element. Material near the blade moves; material far from it doesn't. In RAM, the acoustic energy penetrates the entire volume of the material simultaneously — top, bottom, sides, center — creating what engineers describe as a bulk flow pattern that is impossible to replicate with mechanical means.
This has profound implications for high viscosity processing.
Why RAM Excels at High Viscosity Mixing
1. Overcome Mechanical Restrictions From Conventional Mixers
Traditional, blade and axis technologies can work through early stages of wetting and possibly incorporation, but often overheat or grind to a halt when mixing starts and the viscosity increases.
Every highly viscous mixing process requires three steps:
- wetting
- incorporation
- mixing phases
Without the mechanical limitations of axis/blade methods that require all materials to pass through a limited mixing zone, RAM technology performs all three steps simultaneously and consistently throughout the mixing vessel, reducing processing time by orders of magnitude.
2. No Shear Damage At Any Viscosity
RAM technology is a “non-contact” mixing method requiring no blades, propellers, or other engineered devices to cause mixing. This also means that the high shear traditionally associated with viscous materials can be eliminated, allowing delicate or hazardous materials to be processed rapidly without excessive heat build-up or physical shear stress.
3. Achieve Uniformity in High Viscosity Materials Up to 100x Faster
The more viscous a material, the more difficult it is to mix traditionally. This means that consistent dispersion and distribution suffer at higher centipoise. These restrictive phenomena are completely avoided using RAM mixers at any scale.
Sound energy wets, incorporates, and mixes materials rapidly, thoroughly and at levels of quality not previously possible. Over years of test data across numerous industrial installations, RAM devices have delivered exceptional results, well into the tens of millions of centipoise.
RAM High Viscosity Mixer Accessories, Temperature Control and Vacuum
Every RAM device’s mixing parameter variables can be enhanced by combinations of vacuum, mixing payload temperature control, and other accessories. Viscous materials often mix more effectively at higher temperatures and under vacuum. RAM systems provide these functions before, during, and after actual mixing operations. This means that idle, degassing time, and failed batches due to the wrong temperature are eliminated.
Get a FREE ResonantAcoustic® Mixing Demo
We can schedule an on-site or online video demonstration with a LabRAM I or II (bench scale) mixer to show you the incredible versatility of RAM high viscosity mixing technology. We can mix any materials you wish to test, and we love challenging mixes!
- Mix 10x to 100x faster
- Eliminate cleanup & cross contamination
- Exceptionally thorough and consistent mixing
- Only available through Resodyn
HOW RAM HIGH VISCOSITY MIXERS DELIVER RESULTS 10x - 100x FASTER
The Mechanics of RAM Mixing
RAM's high viscosity mixer drives intense liquid to particle interaction at the wetting stage of viscous ingredient processing through Faraday Instabilities, throughout the materials instantly and continuously.
After incorporation, RAM’s sound energy enables mixing at high viscosities. Without restrictions of mechanical mixing methods and the heat and sheer they generate, RAM allows highly viscous materials to be mixed at the densest levels.
- Vertical vessel movement of 60 x/second and 0.55” / 14 mm displacement, at up to 100 g of acceleration generates intense particle motion.
- RAM’s primary viscous mixing mechanism is intense liquid and solids material boundary interaction, and highly effective sound energy facilitating and accelerating mixing.
- The addition of processing vacuum or temperature improves many viscous ingredient mixes and aids in degassing.
Acoustic Energy Penetrates Where Blades Cannot
The fundamental limitation of mechanical mixing is that it relies on the material to transmit force from the mixing element outward. In low viscosity fluids — water, thin solutions — this works reasonably well because the fluid flows easily. In high viscosity materials, force transmission is poor. The material near the blade moves; the material further away doesn't.
Acoustic energy doesn't have this limitation. Sound waves propagate through materials based on their acoustic properties, not their viscosity. A high viscosity paste transmits acoustic energy just as effectively as a thin liquid — which means RAM achieves the same whole-batch mixing in a thick, resistant material that would defeat any conventional mixer.
The practical result: RAM processes high viscosity materials in 1–5 minutes that would take conventional equipment 60–180 minutes — because there are no dead zones, no waiting for slow mixing fronts to reach the edges of the batch.
Stop Excessive Heat and Shear
- Traditional high viscosity mixers require all ingredients to traverse the entire vessel to repeatedly enter and exit a small, mechanically driven mixing area to achieve proper mixedness.
- Viscous materials experience high temperature generation and physical shear, damaging many ingredients. RAM technology activates all ingredients throughout the vessel immediately, eliminating material motion without mixing. RAM mixes everywhere in the vessel without mechanical devices or accessories, reducing temperature generation and eliminating physical shear.
Bringing Quality to High cP Processing
- High quality viscous performance requires thorough distribution of solids in the liquid matrix, for consistent processing characteristics at any place in the final product.
- RAM’s intense and pervasive processing facilitates solid particle separation and dispersion, improving dispersion, consistency, and performance.
Real-World Applications
Battery electrode slurries. Cathode and anode slurries for lithium-ion and solid-state batteries are among the most challenging high viscosity mixing applications. RAM routinely reduces electrode slurry processing time from 45–90 minutes to 2–5 minutes, while delivering superior homogeneity that directly translates to better, more consistent cell performance.
Pharmaceutical semi-solids. Topical creams, ointments, and pastes present a classic high viscosity challenge: API must be uniformly dispersed through a viscous, often multi-phase base without shear-induced degradation. RAM achieves this in minutes rather than hours, with API uniformity that meets FDA content uniformity requirements on the first blend.
Ceramic pastes and slurries. Advanced ceramics processing often involves highly filled, high viscosity slurries that are difficult to homogenize and prone to settling or agglomeration. RAM delivers thorough dispersion of ceramic particles without the extended ball milling times that conventional processing requires.
Energetic materials. The defense and aerospace industries have adopted RAM for processing energetic material pastes and compositions where both the viscosity challenge and the sensitivity of the materials make conventional mixing hazardous and unreliable.
Adhesives and sealants. High viscosity adhesive formulations — filled epoxies, polyurethane sealants, silicone compounds — benefit enormously from RAM's ability to uniformly disperse fillers, pigments, and reactive components throughout a viscous matrix without introducing air or causing pre-cure degradation.
Behind the Numbers
The performance advantage of RAM for high viscosity mixing can be summarized simply:
- Processing time: 1–5 minutes vs. 30–180 minutes with conventional mixing
- Blend uniformity: RSD <1% routinely achieved
- Scale-up: Direct from lab to production, zero reformulation
- Equipment: One unit replaces four (mixer, mill, sieve, coat)
- Material integrity: No shear damage, no heat generation, no contamination
VIDEO'S ON RAM HIGH VISCOSITY MIXING
Rocket Motor Static Fire: Composite Propellant made with RAM by The Falcon Project LTD UK
Static fire of a 49 kg composite propellant rocket motor made with RAM:
Boost - Sustained Thrust Profile
Loaded Polymer Blending in Less than 3 Minutes!
To illustrate a heavily loaded polymer blend, two materials of very different particle sizes are blended with a polymer surrogate. This footage documents the nature of the material blending and integration into a heavily loaded (~85%) polymer based paste in just over 2 minutes. The use of RAM™ technology is ideally suited for loading of solids into polymers and mixing to a high rate of dispersion and consistent viscosity throughout the blend.
