The DST series of surface tensiometers from SEO is designed for educational, Quality Control (QC), research, and product development purposes in diverse user applications such as:
- Measurement of surface tension of liquids (liquid-vapour interfaces)
- Measurement of interfacial tension of mixtures (liquid-liquid interfaces)
- Studying the wetting behavior of polymeric materials, composite materials, fibers, metals, and ceramics.
- Determination of properties of surfactants / emulsifying agents.
- Evaluation of the reformulation of paints and inks
- Petroleum and fuel applications
- Chemical / biological applications
The instruments perform precise automated tension measurements using two methods:
- Du Noüy Ring method: The Du Noüy Ring is immersed deep within a liquid and pulled up slowly through the liquid-vapour interface. The maximum downward force on the ring is measured using an electrobalance. The surface tension is calculated from the force and other known parameters of the Pt-Ir ring. A similar procedure is followed in the measurement of interfacial tension between liquids.
- Wilhelmy Plate method:A platinum plate (or Cleam glass/Emery plate) is immersed in a liquid with its flat surface perpendicular to the liquid’s free surface. Then the force acting on the plate is measured by an electrobalance when the system is at equilibrium, and the surface tension is calculated from this measurement. A similar procedure is followed in the measurement of interfacial tension between liquids. This technique provides highly accurate and repeatable measurements.
DST-30
The DST-30 is an easy-to-use tensiometer for performing measurements with both the Du Noüy Ring and Wilhelmy Plate methods. It has the following features:
- The sample stage is operated manually with precision and ease.
- Automated force measurements are performed by the software.
- The surface (interface) tension results are obtained quickly with no additional steps or calculations.
- It has an ergonomic, user-friendly design
- Test results are digitally displayed on a touch-screen LCD display.
- Data can be exported to Excel on PC
- Optional: A dual chamber for temperature control (-10°C to 120°C) and a heating/cooling circulation system.
DST-60
The DST-60 is an upgraded version of the manual system in which the sample stage operation is automated for both the Du Noüy ring and Wilhelmy plate methods. It has the following features:
- Automated lifting eliminates errors from manual operation and allows for accurate, repeatable measurements.
- Upgraded ability to perform analyses on larger samples.
- Force measurements are performed with a higher precision compared to DST-30.
- Optional: A dual chamber for temperature control (-10°C to 120°C) and a heating/cooling circulation system.
- Test results are displayed digitally on the PC and a touch-screen LCD display. DST-60 also has an additional print function for results.
The following table offers a comparison of product specifications for choosing the right instrument for suitable applications:
Dynamic Contact Angle and Surface Tension
The DCA 200 series of analyzers are all-in-one versatile instruments designed for quality control (QC), educational, research, and product development purposes in a wide range of applications such as:
- Analysis and improvement of adhesion properties
- Determination of properties of surfactants / emulsifying agents
- Surface wettability of polymeric materials, composite materials, fibers, metals, and ceramics
- Effect of liquid absorbency on papers, textiles, diapers
- Evaluation of the reformulation of paints and inks
- Determination of cleanliness and surface/topological homogeneity of solids, sheets, and fibers
- Temporal changes in liquid surface tension
- Dispersive and non-dispersive solid surface tension determination
- Advanced studies in chemical/biological processes
The DCA 200 offers the following analyses and solutions for characterizing multiple surface chemistry phenomena:
- Surface tension and interfacial tension of liquids using Wilhelmy Plate and Du Nuoy Ring methods
- Dynamic Contact Angle of the liquid-solid interface: Advancing – Receding angle hysteresis using the Wilhelmy plate method.
- Fiber Contact Angle
- Dynamic Contact angle of powders and other porous materials using the Washburn method
- Dry material absorption, wicking rate
- Density / Penetration / Sedimentation measurements
- Zisman plots of liquid-solid surfaces: critical surface tension calculations
- Surface energies: geometric mean, harmonic mean (reciprocal), Lewis acid/base (polar plus/minus), surface homogeneity
- Critical Micelle Concentration (CMC) measurements (Optional)
For an overview of the measurement methods and calculations, click here.
Features and benefits:
The DCA 200 has an ergonomic, user-friendly design powered by SEO’s Quantum-S software which offers several benefits such as:
- Automated stage operation: Automatic stage controllers eliminate human errors in measurements for higher precision, accuracy, and reliability of results
- Highly flexible operations: Quantum-S offers method/recipe creation and storage, and an automated program run mode
- Automatic data acquisition and analysis: A complete range of analyses are performed automatically to determine surface characteristics quickly
- Continuous characterizations: Real-time display of test liquid temperature, real-time buoyancy correction, and temporal analyses during hydration
- Advanced analysis: Wetting behavior can be measured and correlated to surface composition and surface treatment
- Quality Control: Routine parameters, such as surface cleanliness, topography, and modification are easily monitored with a non-destructive test method
- Optional features:
- CMC doser, built-in stirrer for liquid mix
- Temperature control accessories: heating/cooling bath
- USB connection to PC: Data display on PC and data export to Excel
Full list of product specifications:
For more information on the instrument and usage in specific applications, contact us.