Rheological properties

detailed specification sheets from www.malvern.co.uk/bohlincvor

Rheological instruments backed withrheological experience

Bohlin

2 Bohlin C-VOR

Bohlin Rheological measurement made easy

www.malvern.co.uk

A high resolution, modular rheometer and dynamic spectrometer system with triple-modemotor control which allows strain, stress or shear rate controlled measurement to beperformed. A built-in normal force sensor is used for a range of measurement, gap controland sample loading protocols.

The Bohlin C-VOR is not simply an advanced rheology research tool, it is a completesystem ready to measure what you need, in ways you define and with the accuracy whichthe demands of modern industry and research require.

Enables the motor to be engaged andrun as a conventional servo motorallowing true strain controlledmeasurements such as relaxation.Alternatively, the motor can be run atpre-set speeds to generate shear ratecontrolled data. Conversely, by runningin open-loop mode, stress controlledtests such as creep and creep recoverycan be performed.

Inductive motor technology avoids usingpermanent magnets and results in a lowinertia motor. The motor design givesadditional benefits of superb low torqueresponse, does not require user re-calibration, and cannot be affected byany ambient magnetic fields. Thesedesign principles and characteristicscreate a motor with outstandingtransient response – a step change instrain can be effected in less than 10ms.

Triple motor control – with inductive motortechnology

Bohlin Rheological measurement made easy

— High resolution normal force controlHigh resolution normal force sensorincorporated directly into the C-VORmechanics which gives both extremesensitivity and a wide range. Capable ofmeasuring just 0.1g, data for the first normalstress difference can be generated at even lowvalues of thrust. In oscillation, the sensor canbe used to compress or tension a sample witha pre-defined force using ‘autotension’ mode

— Wide dynamic rangeMotor technology combined with an inherentlysensitive air bearing generates a dynamicrange in torque in excess of 1:1 million, andmeans that large variations in modulus duringmaterial transitions can be properly followed.The minimum torque is just 0.1µNm whichenables investigations of even the mostweakly structured viscoelastic dispersions.

— Unique high speed facilityUnique, high dynamic range position sensortechnology can generate data at high shearrates, applicable to coating applications. Anupper speed of 600rads-1 can achieve shearrates in excess of 5 x 10 5s-1.

— Sub micro-strain position sensingAdvanced position sensor technology hasobvious benefits in sensitivity for low strainmeasurement. Complemented by the C-VOR’slow torque response, this enables extremelysensitive creep and recovery measurements tobe performed.

— Flexible temperature controlFor maximum flexibility and to suit all testingrequirements, the C-VOR can be quickly andeasily configured with a wide range oftemperature control units. These include fluidscirculators, Peltier devices, electrically heatedplates and a forced gas oven with a liquidnitrogen cooling option.

Complete rheology – total control

3 Bohlin C-VOR www.malvern.co.uk

Bohlin Rheological measurement made easy

4 Bohlin C-VOR www.malvern.co.uk

— Parallel plate, cone and plate

— Coaxial cylinders (DIN)

— Double gap

— Small sample cell

— Roughened and serrated systems

— Vane tool

— Solids and fibre film fixtures

— Vacuum disposable systems for thermosets

— Optical UV curing cell

— Optical analysis cell

— High pressure cells

— Electro-rheology cell

— Humidity enclosure

Optional equipment

Applications – from fluids to solids

— Coatings

— Adhesives

— Cosmetics

— Personal care products

— Foods

— Composites

— Petrochemicals

— Polymers

— Pharmaceuticals

— Asphalt

— Solids

— Low viscosity fluids

As you would expect, all software provided with the Bohlin C-VOR is WindowsTM compatibleand designed with flexibility and ease of use in mind and includes an in-built rheology“textbook” and topic search facility.

Data analysis programs, which can be incorporated into user-defined templates forautomated procedures, include advanced Model Fitting, Time-Temperature Superposition(WLF), advanced viscoelastic analysis (VE data conversion) and molecular weightdetermination. Multiwave analysis is available as an option.

Bohlin Rheological measurement made easy

5 Bohlin C-VOR www.malvern.co.uk

Software to make it happen

Viscometry measures viscosity as a function of shearstress or shear rate. Measurements include single valueof shear rate (or stress), table of shear rates (or stresses),continuous shear rate (or stress) ramp (including yieldstress) and complex shear rate (or stress) profile.Temperature control can be isothermal (time sweep), or follow defined gradients or step changes.

Creep and Creep Recovery measures the creepcompliance and recoverable compliance as a functionof time. User defined sampling modes can be set. Zeroshear viscosity and yield stress can be determined.

Oscillation measures the dynamic viscoelastic propertiesas a function of frequency, Measurements include singlefrequency, frequency sweep, amplitude sweep, timesweep and temperature sweep (gradient, step change orprofile). Tests can be performed at constant stress orconstant strain amplitude (under direct control). Oscillationmeasurements can be superimposed on steady shear.Partial wave and Multiwave sampling are available.

Relaxation measures relaxation modulus as a functionof time following a step change in strain. The relaxationspectrum and zero shear viscosity can be determined.

detailed specifications at www.malvern.co.uk

© 2005 MRK659-02

Malvern Instruments LimitedEnigma Business Park • Grovewood Road • Malvern • Worcestershire • UK • WR14 1XZTel: +44 (0)1684 892456 • Fax: +44 (0)1684 892789

Malvern Instruments WorldwideSales and service centres in over 50 countries for details visit www.malvern.co.uk/contact

Malvern Instruments is part of Spectris plc, the Precision Instrumentation and Controls Company.

Overview Bohlin C-VORComprehensive rheological analysis

Torque range: 0.1µNm to 150mNm0.1µNm to 200mNm

Torque resolution: Better than 1nNmPosition resolution: 50nradFrequency range: 1µHz to 150HzControlled speed range (CR mode): 0.01mrad s-1 to 600rad s-1

Measurable speed range (CS mode): 10nrad s-1 to 600rad s-1

Normal force N1 measurement range: 0.001N to 20N (50N optional)Step change in strain: <10msTemperature range (dependent on control used): -150ºC to 550ºC

Temperature controlsFluids Circulator: -40ºC to 250ºCETO (Extended Temperature Option): -15ºC to 300ºCMelts Oven: ambient to 450ºCPeltier Plate: -30ºC to 200ºCPeltier Cylinder: -20ºC to 180ºCUniversal Peltier Option – Coaxial Cylinder or Cone/Plate GeometriesETC (Extended Temperature Cell): ambient to 550ºCETC with optional LTU (Low Temperature Unit): -150ºC to 550ºC

Nominal operating voltage 110 or 220VSize (with Peltier plate) 52cm (H) x 29cm (W) x 34cm (D)Weight (with Peltier plate) 27kg

Optional equipmentMeasuring SystemsVacuum Disposable Plates: Peltier Plate, Melts Oven or ETOHigh Pressure (Sealed Cell): 40bar pressure, 30ºC to 150ºCHigh Pressure/High Temperature Cell: 300bar pressure, ambient to 300ºCOptical UV Curing CellOptical Analysis CellImmobilisation CellElectro-rheology Cell: DC voltage up to c.10kV

Bohlin

Every Bohlin C-VOR from Malvern is backed with the technical and sales support of Malvern Instruments, the only material characterization company with the resources andequipment to measure particle size and shape, zeta potential and molecular weight as wellas the expertise to advise on how these parameters influence rheological properties.