GenMooney measures the viscosity of unvulcanized rubber - natural, synthetic or regenerated, mixed or unmixed. It warms up quickly, holds its temperature and calibrates itself before each experiment, which is what keeps readings comparable from one batch to the next.
Mooney viscosity operation video.
A second recording of the same machine.
Three tests live in one instrument, and the parts that decide whether a reading can be trusted - temperature and torque - are each measured on their own hardware.
The software returns the following values at the end of a run.
| Value | What it means |
|---|---|
| Minimum Mooney value | The lowest reading within the 30 s before the finish. |
| MY | Mooney viscosity value once the viscosity time has expired. |
| MY-T | Mooney value at the corresponding time. |
| TR80 | The time required for the stress relaxation to reach 80%. |
| LM-Min | Torque value at the minimum Mooney viscosity in the scorch test. |
| Ml | Initial Mooney viscosity. |
| Me | Mooney viscosity value. |
| MRe | Mooney stress relaxation test. |
The machine is run from a computer; the air supply is not included.
| Item | Value |
|---|---|
| Temperature range | Room temperature to 200 °C |
| Temperature display resolution | 0.1 °C |
| Rotor frequency | 2 ±0.02 rpm |
| Mooney viscosity range | 0 to 200 Mooney |
| Torque unit | kg-cm, lb-in, N-m Mooney |
| Test time | Set freely, and can be changed mid-run |
| Control | By computer |
| Air pressure | 65 psi (4.6 bar), air compressor not included |
| Specimen dimension | 5 cm |
| Display | NextGen software |
| Dimensions (W × D × H) | 12.2 × 22 × 24.40″ (31 × 56 × 62 cm) |
| Weight | 770 lbs (350 kg) |
| Power | 110 V / 60 Hz or 220 V / 50 Hz |
Tell us the compound and the standard you work to, and we will confirm the configuration and what the software reports. Send a quick request online.
Need Additional Quality Control Equipment to Build Your Laboratory?
Mooney viscosity testing is only one part of a complete quality control laboratory. NextGen can help you equip your entire lab with rheometers and viscometers, abrasion and flex testers, ageing and salt spray chambers, hardness and rebound testers, specimen cutting presses, and other supporting solutions, all coordinated as one complete project.
The main difference between silicone and rubber is that most rubber forms have backbones containing carbon-carbon bonds. On the other hand, the backbone of silicone is comprised of silicon and oxygen. Both silicon and rubber are types of elastomer.
The major source of commercial natural rubber latex is the Hevea brasilliensis, more commonly known as the Amazonian rubber tree. It is a member of the Euphorbiaceae from the spurge family. The species is a good option since it can thrive well under cultivation. When properly managed, the tree responds nicely to wounding by providing more latex for many years.
The cure rate is a crucial vulcanization parameter because it defines the time that the compound needs to be cured. This is known as the cure time. The thermo plasticity is taken from the difference between the initial viscosity and the minimum viscosity.
Pre-vulcanized natural rubbers present Mooney viscosity that range between 60 and 90. In tire manufacturing the acceptable range used is anywhere from 75 to 80.
The value of viscosity that the Mooney Viscometer determines only depends on the molecular weight, molecular structure, and non-rubber components present in the rubber specimen. Because the behavior of rubber is that of a non-Newtonian fluid, no direct relationship exists between viscosity and molecular weight.
Stress relaxation is not only an elastic response. It is a viscous response as well. Stress relaxation does not depend on the molecular weight. A slow rate is an indication of a higher elastic portion in the entire specimen. A rapid rate, on the other hand, is an indication of a higher viscous composition. The stress relaxation rate correlates to the data points of the rubber structure such as chain brancing, weight distribution, and gel content.
Yes, absolutely! The increase in viscosity can be detected by the machine. Thus, the test procedure can be employed when measuring the scorch or incipient cure time as well as the cure rate during the initial stages of vulcanization.
An arbitrary unit, a Mooney unit is used for measuring the plasticity of unvulcanized or raw rubber. The plastic expressed in Mooney units is equivalent to the torque, which is measured using an arbitrary scale. It is on a disc inside a vessel containing rubber rotating at two RPM (revolutions per minute, at a temperature setting of 100o C.
It can be defined simply as the shearing torque providing resistance to the rotation of the rotor or cylindrical metal disc that is embedded in a rubber specimen with a cylindrical cavity.
The Mooney viscosity test is among the most prevalent procedures done in the rubber industry at present. It is typically used for measuring raw rubber viscosity as well as to depict the quality of both synthetic and natural rubber.
The Mooney Viscometer confirms to both the ISO 289 industry standards as well as the ASTM D1646 standards.
When the rotor makes an abrupt stop, the stress or torque on the rotor goes down at rate that is promptly measured. The stress relaxation is determined by the type of specimen rubber, as well as the test’s temperature.
The answer is YES. The ASTM standard describes a method to measure the initial vulcanization rate. When testing compounded rubber at a temperature that may possibly result to vulcanization, the reaction generates an increase in torque. This can then be measured using the equipment.
Parts 1 and 2 of the ISO 289 describes the process of Mooney viscosity determination as well as the pre-vulcanization characteristics. The primary difference between the ISO and the ASTM Standard is this: ISO 289 has no provisions for specimen preparation on a mill. The ASTM method, on the other hand, allows the preparation of the milling specimen for a Mooney viscosity test. The use of milling may have an impact on different types of rubber. Thus, the test might produce different results.
After cutting a circular sample from a 6-8mm rubber sheet, the sample is pierced in the middle to form a donut shape. This allows the spindle to pass through the specimen. The temperature begins to rise where the sample reaches thermal equilibrium. The spindle begins to turn and the Mooney value typically remains constant until the temperature reaches higher levels where vulcanization starts and the Mooney value increases.
The Mooney test is frequently used to classify the quality of both natural and synthetic rubber types.
The components for any Mooney viscometer include a rotating spindle and heated dies. The torque on the spindle is what measures the Mooney value.
Melvin Mooney invented the Mooney viscometer along with many other equipment types for the rubber industry.
Parts 1 and 2 describe the determination of Mooney Viscosity and the pre-vulcanization characteristics. The main difference from the ISO to the ASTM standard is that ISO 289 does not provide for sample preparation on a mill - while the ASTM method allows milling to prepare the sample for Mooney viscosity testing. Different rubbers may be affected by the use of milling in which cause the results will differ.
Yes, the ASTM standard defines a method for measuring the initial rate of vulcanization. When compounded rubber is tested at a temperature where vulcanization may occur, the reaction produces an increase in torque which can then be measured with the instrument.
When the rotor stops abruptly, the torque or stress on the rotor decreases at a rate which is then measured. The stress relaxation depends on the rubber sample type and the temperature of the test.
The GenMooney Mooney Viscometer follows both the ASTM D1646 standard as well as the ISO 289 industry standard.
It is defined as the shearing torque resisting rotation of a cylindrical metal disc (or rotor) embedded in a rubber sample with a cylindrical cavity.
Absolutely! It can be detected with an increase in viscosity. Because of this, the testing procedure can be used to measure incipient cure (Scorch) time and the rate of cure during the beginning stages of vulcanization.
Stress relaxation is both an elastic and viscous response. Viscosity and stress relaxation do not depend on molecular weight. A slow rate indicates a higher elastic component in the overall sample while a rapid rate indicates a higher viscous component. The rate of stress relaxation correlates with the rubber structure data points such as molecular weight distribution, chain brancing and gel content.
Viscosity values determined by the Mooney Viscometer depend only on molecular structure, molecular weight, and non-rubber constituents that are present in the rubber sample. Seeing as rubber behaves as a non-Newtonian fluid, there is no direct relationship between molecular weight and viscosity.