Brookfield cone/plate viscometer

The pressure varies only over about a ten psi range between the injector and producer, even with the higher viscosity foam present as compared to the viscosity of the other fluids. The higher viscosity of the foam was obtained by assigning a fictitiously high viscosity to the surfactant, such that the blend of v/ater and surfactant which was injected had a viscosity of 62 cp (kPa-s), which is the viscosity measured for foam in the laboratory experiments (with a Brookfield cone plate viscometer). 

The viscosities of some semidilute solutions were measured by using a Brookfield cone/plate viscometer. All the measurements were performed at temperature 25 C. 

Brookfield has introduced a new digital cone—plate viscometer in two versions. The CAP 1000 is a single speed instmment (12,000 or 3, 000 with 60 Hz current) that upgrades the ICl cone—plate design (ASTM D4287). The CAP 2000 is a multispeed viscometer with a viscosity range of 1 15, 000 mPa-s. This instmment covers a wide range of shear rates (166-26, 600 ) and complements the low shear WeUs-Brookfield viscometer. 

Blood is a non-Newtonian liquid showing a shear-dependent viscosity. At low rates of shear erythrocytes form cylindrical aggregates (rouleaux) which break up when the rate of shear is increased. Calculations show [82] that the shear rate (D) associated with blood flow in a large vessel such as the aorta is about 100 s but for flow in the capillaries it rises to about 10(K) s The flow characteristics of blood are similar to those of emulsions except that, while shear deformation of oil globules can occur with a consequent change in surface tension, no change in membrane tensions occurs on cell deformation. Fig. 9.32 shows the viscosity of blood at low shear rates, measured in a Brookfield LVT micro cone-plate viscometer. 

With several springs, which function as torque gauges, and a number of spindles, viscosities can be measured up to 10 mPa-s with the Brookfield viscometer. The shear rates depend on the model and the sensor system they are ca 0.1 100 for the disk spindles, <132 for concentric cylinders, and <1500 for the cone—plate forlow viscosity samples. Viscosities at very low (ca 10 — 1 )) shear rates can be measured with the concentric... 

The Nametre Rotary B rotational viscometer measures torque in terms of the current needed to drive the d-c motor at a given speed while a material is under test. The standard sensors are coaxial cylinders or Brookfield disk-type spindles, but a cone—plate system is also available. The viscosity range for the coaxial cylinder sensors is 5 to 5 x 1(T mPa-s, and the maximum shear rate is 200. ... 

Rheological measurements. Routine viscosity measurements were made with a Wells-Brookfield micro-cone and plate viscometer, or a Brookfield LVT(D) viscometer with UL adapter. Viscosity-temperature profiles were obtained using the latter coupled via an insulated heating jacket to a Haake F3C circulator and PG100 temperature programmer or microcomputer and suitable interface. Signals from the viscometer and a suitably placed thermocouple were recorded on an X-Y recorder, or captured directly by an HP laboratory data system. 

Assays. Nitrogen assays to determine 1-amidoethylene unit content were done by Kjeldahl method. Limiting viscosity numbers were determined from 4 or more viscosity measurements made on a Cannon-Fenske capillary viscometer at 30°C. Data was extrapolated to 0 g/dL polymer concentration using the Huggins equation(44) for nonionic polymers and the Fuoss equation(45) for polyelectrolytes. Equipment. Viscosities were measured using Cannon-Fenske capillary viscometers and a Brookfield LV Microvis, cone and plate viscometer with a CP-40, 0.8° cone. Capillary viscometers received 10 mL of a sample for testing while the cone and plate viscometer received 0.50 mL. 

Two Brookfield viscometers were used to collect the data necessary for rheologic property studies of wet grains a Brookfield RVDV III viscometer with a cone-and-plate spindle and a Brookfield HBDV III viscometer with a double helical ribbon impeller attachment. The Brookfield RVDV III had a full-scale torque of 7187 dyn-cm, and the HBDV III had a full-scale torque of 57,496 dyn-cm. Each viscometer had a maximum rotational speed of 250 rpm. Both viscometers had accuracy limits of 5% full-scale torque. 

The method and type of equipment used also vary with the type of adhesive. As an example, the viscosity of electrically conductive adhesives is measured according to ASTM D1824, Apparent Viscosity of Plastisols and Organosols at Low-Shear Rates by Brookfield Viscosity The viscosity of typical electrically conductive die-attach adhesives is measured with a Brookfield HBT viscometer with Spindle TB and Speed 5. For higher-viscosity conductive adhesives and for underfill adhesives, a Brookfield RVT or RVF viscometer is used with Spindles 6 or 7 at speeds of 4—10.4 rpm. Another Brookfield viscometer, the Cone-and-plate viscometer with a CP-51 spindle is used for low-to-intermediate viscosity adhesives. Finally, the Brookfield HAT and HBT instruments are used for the high-viscosity (1-2 million cP at 1 rpm) adhesives typically used in SMT applications. ... 

Viscometric properties of the three polymer systems were studied under dilute (<1%) and concentrated (10%) conditions utilizing an Ubbelohde dilution viscometer for the former and a cone-plate Brookfield digital viscometer for the latter. Polymer samples were dissolved in an agpropriate salt solution. Viscosities were determined at 25 0.i C taking precautions to keep all solutions dust free. 

Viscosities of liquid resins are typically determined with a Cannon-Fenske capillary viscometer at 25°C, or a Brookfield viscometer. The viscosity depends on the temperature, as illustrated in Figure 2. Viscosities of soUd epoxy resins are determined in butyl carbitol (diethylene glycol monobutyl ether) solutions (40% solids content) and by comparison with standard bubble tubes (Gardner-Holdt bubble viscosity). The Gardner color of the same resin solution is determined by comparison with a standard color disk. Recently, data have been reported for solid epoxy resins using the ICI Cone and Plate viscometers, which are much more time-efficient because they do not require sample dissolution. 

Binding ratios of SDS (BHD Ltd.) and CPC (Tokyo Kasei Ltd.) to HPC (M.W. =11 -I5xl0 Tokyo Kasei Ltd.) were determined at 30 °C by an equilibrium dialysis method. Cloud point of an HPC solution was observed by the naked eye. Amounts of p-dimethylaminoazobenzene (Nakarai Ltd.) solubilized by the surfactant micelle and the surfactant-polymer complex were determined at 30 °C by colorimetry at 1 = 418 nm. Viscosity was measured by an Ubbelohde-type capillary viscometer, a cone-plate rotary viscometer, or a Brookfield-type rotary viscometer at 25 or 30 °C. Mean diameter of secondary particles of kaolinite in its dilute suspension (1 g/dl) was estimated by a Coulter counter (type TA-II) in 154 mmol/dm NaCl at room temperature. 

For the purpose of this research, brief information about cone and plate geometry viscometer will be given. As noted in Brookfield catalog, cone and plate viscometer offers absolute viscosity determination with precise shear rate and shear stress information. The sample volume is extremely small amount and temperature controlled is easily accomplished. Cone and plate geometry viscometer is particularly advanced rheological analysis of non-Newtonian fluids (Phair Kaiser, 2009). 

The viscosity measurement was carried out in semi-clean room condition and the ambient temperature is maintained at 25°C. This is the key factor which might be affects the printing quality. Brookfield viscometer Model RV-DV cone plate geometry with CP-52 spindle, using a plate 1.2 cm radius and a cone angle of 3 ° is used. Viscometer speed was set at 0.5, 1.0,1.5, 2.0 and 2.5 RPM. The viscosity and torque readings were recorded. Viscosity of the paste for the sample 2, 4, 6, 8, 10 and 12 wt% of thinner was achieved from the measurement. 

The cone and plate viscometer is ideal for determining the absolute viscosity of fluids in a small sample volume. The commercially available cone and plate viscometer (e.g., Wells-Brookfield), a precise torque-measuring system, which consists of a calibrated beryllium-copper spring connecting the drive mechanism to a rotating cone, senses the resistance to rotation caused by the presence of sample fluid between the cone and a stationary flat plate. The resistance to the rotation of the cone produces a torque that is proportional to the shear stress in the fluid. The amount of torque is displayed digitally. A commercially available viscometer is illustrated in Figure 7-3fi. 

Figure 7-3. (a) A digital programmable viscometer. (Courtesy of Brookfield Engineering Laboratories.) (b) Cone and plate viscometer. (Courtesy of Brookfield Engineering Laboratories.)... 

The viscosities of adhesives and sealants can be measured with various types of equipment such as the spindle (e.g. Brookfield), cone and plate, bob and couette viscometers, and torque rheometers. The viscosity value of an adhesive or sealant is dependent on the shear rate at which the measmement is made, as shown in Figme 2. 

FTIR spectra were obtained on a MIDAC spectrophotometer. The H NMR and NMR spectra were collected on a 300-MHz Bruker AM spectrometer, using deuterated water as a solvent and with trimethylsilane (TMS) as internal standard. Viscosities of the copolymer solutions (50-50, wt-wt) were measure by a cone and plate viscometer, using a Cap 2000 Viscometer (Brookfield Engineering Laboratories, Inc., Stoughton, MA), at 25°C. An Instron universal testing machine (Instron Model 4204, Instron Corp., Canton, MA) was used to determine mechanical properties. 

A number of techniques have been developed to measure melt viscosity. Some of these are listed in Table 3.8. Rotational viscometers are of varied structures. The Couette cup-and-bob viscometer consists of a stationary inner cylinder, bob, and an outer cylinder, cup, which is rotated. Shear stress is measured in terms of the required torque needed to achieve a fixed rotation rate for a specific radius differential between the radius of the bob and the cup. The Brookfield viscometer is a bob-and-cup viscometer. The Mooney viscometer, often used in the rubber industry, measures the torque needed to revolve a rotor at a specified rate. In the cone-and-plate assemblies the melt is sheared between a flat plate and a broad cone whose apex contacts the plate containing the melt. 

Viscosity measurements were made at 25°C and 65% relative humidity with a Wells-Brookfield micro-viscometer equipped with a cone and plate. 

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