Drop and Bubble Shape Tensiometer PAT-1

Most modern method to measure the surface and interfacial tension of liquids
Principle is based on the analysis of the shape of pendent and sessile drops or buoyant and captive bubbles. The instrument is well suited to determine the contact angle of liquids on solid surface. The apparatus is driven by a modern Windows software. Modular extension for different applications.
PAT-1

Instrument parts
basic platform on which all parts are safely mounted
computer controlled dosing system
adjustable temperature controlled measuring cell (low temperature range 10 to 80 °C, high temperature range 10 to 1000 °C)
CCD-camera with fixed objectives
high-performance frame grabber installed in the PC
cold back lighting with continuously adjustable intensity

Features of the instrument

This instrument allows measuring quite a number of interfacial properties. In addition to the properties of a standard drop and bubble instruments the PAT-1 (Profile Analysis Tensiometer) from SINTERFACE allows unique experiments and gives access to quantities not easy available by other methods:

  • surface and interfacial tension of liquids
  • static and dynamic contact angle according to the sessile drop method
  • surface rheological studies to measure the dilational elasticity and viscosity
  • capillary pressure measurements for iso-dense liquid/liquid systems
  • short time interfacial tensions with extra module DPA-1
  • direct drop-drop, bubble-bubble, and dropbubble interactions with a special micro manipulator (extra equipment DBMM-1)
  • fast oscillations with extra module ODBA-1
  • time dependence of all measured quantities
  • online temperature control
  • area or volume can be kept constant during the measurement
  • 0.1 s resolution over a period of seconds up to days

Main features of the software

  • on-line interfacial tension/contact angle calculation
  • calculation of the surface free energy of solids according to the equation of state by Li and Neumann
  • control of the dosing system for accurate changes of a drop or bubble (transient or harmonic changes)
  • control of a piezo system (additional equipment) for active and very accurate control loop to keep constant either volume or area of drop or bubble
  • smooth oscillations with piezo system harmonic and transient relaxation experiments
  • calculation of the dilation rheological parameters from relaxation measurements via Fourier analysis

    More information to be downloaded as PAT-1.pdf ( 401kB).
    A general measuring example is available as PAT-1P-Example.pdf (167 kB).
    A measuring example for interfacial tension measurement is available as PAT-1P-Example-Inter.pdf (139 kB).
    A measuring example for the measurement of dilational rheology is available as PAT-1P-Example-Rheo.pdf (310 kB).

    SINTERFACE Technologies
    Dr. Reinhard Miller & Dr. Alexander Makievski GbR
    Volmerstraße 5, D-12489 Berlin, Germany
    Phone: +49 30 63923240; Fax: +49 30 63923241; Email: info<at>sinterface<dot>com

    This page last updated: 12.01.2011