Continuous emulsification of polymers and resins
Finely distribute preformed polymers and resins
Polymer and resin emulsions are used as binders in coatings, adhesives and other industrial formulations. A liquid, molten or dissolved polymer or resin phase is finely distributed and stabilised in an immiscible continuous phase, often water.
Cavitron rotor-stator systems provide mechanical emulsification in the product stream. The process described here concerns preformed polymers and resins. It is distinct from molecular dissolution and from their chemical manufacture by emulsion polymerisation.
Control droplet size and stability together
- Viscosity ratio: The viscosities of both phases influence droplet formation and break-up. Temperature-dependent flow behaviour is especially important for melts.
- Interfacial stabilisation: The emulsifier or protective colloid must suit the formulation and adequately stabilise the newly formed interfaces.
- Phase ratio: Concentration and addition sequence influence emulsion type, viscosity and the risk of unwanted phase inversion.
- Temperature profile: Mechanical energy input, cooling and any solidification of the dispersed phase must be coordinated.
Continuous emulsification with defined processing
The metered phases are mixed intensively in the rotor-stator system. Shear and turbulent flow deform and break up droplets. The formulation stabilises the newly created interfaces. The objective is the required droplet size distribution; breaking polymer chains is not an intended mechanism of emulsification.
Tool configuration, speed, throughput and temperature are specified together. Continuous operation also requires controlled phase flows, emulsifier addition, start-up conditions and downstream cooling. Vessel recirculation is an alternative operating mode with a different residence time distribution.
Whether the target quality is achieved in a single pass or requires further processing is assessed for the specific formulation. Storage stability depends on both dispersion quality and formulation.
Benefits at a glance
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Defined droplet break-up
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Reproducible emulsion quality
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Coordinated dosing and processing
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Integrated emulsification and cooling
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Design for formulation and throughput
Benefits for your production
Defined droplet break-up: The active processing zone provides mechanical treatment matched to the emulsion target.
Reproducible quality: Defined formulation and operating parameters support control of droplet size distribution, viscosity and stability.
Connect dosing and processing: The inline stage can be combined directly with controlled phase flows, supporting consistent composition during steady-state operation.
Integrate temperature management: Emulsification and downstream cooling are coordinated, particularly for temperature-dependent viscosity or solidifying resin phases.
Appropriate plant concept: Machine size and the process sequence are selected for throughput, formulation changes and existing infrastructure.
Design based on your emulsion specification
Required information includes polymer or resin type, supplied form, composition of both phases, emulsifier system, phase ratio and viscosities at process temperature. Throughput, permissible temperature range and cooling requirements are also needed.
Agreed quality criteria include droplet size distribution, viscosity, emulsion type and stability under defined storage and application conditions. Melt emulsions also require assessment of behaviour during cooling.
Materials, seals, drive and operating limits are selected to suit the process media. See the Cavitron datasheet for an overview of the machines.
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