Polymer and Petrochemical
Application Notes
Viscosity is an incredibly important property to measure when it comes to the research and development, and quality assurance of petrochemicals and polymers.
The viscosity of lubricating oils and greases at low and high temperatures is used to indicate, for example, their performance and deterioration. Viscosity measurement can also be used to study physical property changes of polymers as they bond with monomers and other polymers in processes such as polymerization, and crosslinking/curing.
Viscosity measurement methods widely adopted in petrochemistry labs have many drawbacks including tedious and time-consuming instrument cleaning and difficulties in dealing with sample hardening and volatilization.
However, these problems are solved with the EMS-1000S Viscometer by Kyoto Electronics Manufacturing (KEM). The EMS-1000S measures samples in autoclavable and hermetically sealable tubes that contain a metallic probe made to spin in the sample medium. The system prevents direct contact between the sample and the instrument, eliminating the need for cleaning between measurements. The system also allows you to control the gaseous atmosphere your sample is exposed to while preventing harmful vapors from escaping. The viscometer’s measurement temperature can be adjusted quickly and accurately, and it is possible to study the hardening/curing process of samples over a measurement range of 0.1 to 1,000,000mPa.s.
Lovingly adopted by major oil producers such as PetroChina Company Limited, the EMS-1000S by trusted analytical instrument maker, KEM, is making viscosity measurement easier and more efficient, inspiring new in-house measurement
standard methodologies.
Features and functions relevant to this industry include:
Wide measurement range
EMS viscometer covers a wide range of viscosity measurement, from 0.1mPa・s to 1,000,000mPa・s. It can measure and observe the viscosity of the polymerization or curing process in monomers.
Accurate temperature control mechanism and small sample quantity
EMS viscometer is equipped with an electronically controlled temperature mechanism, a micro ceramic heater for heating and a peltier element for cooling. The temperature can be controlled with an accuracy of ±0.1°C, from a range of 0 °C to 200 °C. Any heater for temperature control is not necessary to be prepared at customer's site.
The temperature control takes only 10 minutes for the temperature to increase from 25 °C to 200 °C, and 15 minutes for the temperature to decrease from 200°C to 25°C.
When measuring thermoplastic resins, all it takes is to introduce a small piece of the solidified sample at room temperature into the sample container and place the container into the EMS viscometer. The measurement starts by pressing the start button. This shows that the EMS viscometer does not require sample preparation steps like heating and melting steps unlike when rotational viscometer is used.
EMS viscometer is equipped with accurate and quick temperature control system for small sample quantities, accomplishing easy measurement of temperature dependence in viscous sample.
Sequence mode to observe temperature dependency
Software of EMS viscometer is equipped with the function of sequence mode which enables continuous measurements at different temperatures. This function is very useful by just modifying the parameters when evaluating temperature dependency in viscous sample.
The viscometer is also useful when the viscosity behavior is observed for long hours because the instrument has safety function to prevent temperature runaway.
Easy operation for all operators
Unlike Rheometer, EMS viscometer does not require special experiences and knowledge for all operators. The viscometer can measure viscosity in small samples from 0.3mL, afterwhich the operator just need to introduce the disposable container with small sphere into the instrument.
Operators do not need to introduce sample delicately into the container. The sample is enough just to introduce more than 0.3mL which immersed small sphere probe in the disposable container. (Operators do not need to monitor the sample amount introduced into the container. It is possible to introduce more than 0.3mL volume as long as the small sphere is immersed in the sample)
In contrast, when operator uses Rheometer, they always need to take note of the sample quantity to prevent influences from the volume variation.
Evaluation of lubricating oil and grease
The product life and evaluation of deterioration by observing viscosity in lubricating oil and grease under heating conditions has been of great importance in the industry. EMS viscometer enables this evaluation easily and safely by using disposable container sealed with cap.
Non-direct contact measurement by using disposable sample container
When Rotational viscometer is used, the cleaning process after measurement is a struggle for all operators. Especially when highly viscous sample like polymer is measured, it becomes solidified at room temperature, causing difficulties in removing and cleaning.
The solidified sample that is not removed completely on sensors and other parts of the Rotational viscometer sometimes causes measurement errors and malfunctions by generating unexpected stress.
In contrast, the EMS viscometer adopts non-contact measurement method by using disposable containers. This principle reduces possibility of malfunction caused by solidified samples and enables viscosity measurement in sticky samples.
Applications
Major applications of EMS viscometer for this industry are as below.
Aqueous Polymers
Fluid mechanics are important in chemical engineering – the corresponding dimension less numbers (Reynolds Number, Prandtl Number) are widely used in optimization and scale-up of chemical synthesis. To evaluate these dimensionless numbers, the viscosity in the process under investigation must be examined under realistic conditions. This often requires viscosity measurements at elevated temperatures and pressures.
The same is the case if reaction kinetics must be studied under real conditions based on viscosity changes which occur during a reaction.
The EMS Viscometer is the ideal tool for such applications, as it easily allows to monitor the viscosity during reactions at elevated temperatures and pressures. With the EMS Viscometer it is thus possible, for example, to monitor the viscosity during a polymerization process at 150°C under a pressure of 5 bar.
Adhesives
Viscosity is an important physical property of any adhesive. With normal viscometers, however, viscosity measurements of adhesives require a vast amount of time as cleaning is difficult or nearly impossible.
The disposable measuring cell of the EMS Viscometer brings decisive time savings to such measurements as cleaning is no longer necessary.
Ionic Liquids
Ionic liquids (IL) are salts in a liquid state. They are often used in electric batteries. For this application, the viscosity of the ionic liquid should be as low as possible, as the ability of the ionic liquid to transport charge is the better the lower its viscosity. An ionic liquid suitable to be used in electric batteries must therefore have a low viscosity over a wide temperature range. Few ionic liquids remain liquid at extremely low temperatures and in many cases their viscosities become prohibitively high for electrochemical applications. Often, mixtures of different ionic liquids or the use of additives helps to mitigate this problem.
When developing a new ionic liquid, normally only small amounts of the product are available to perform viscosity measurements at different temperatures and to examine the influence of additives or the addition of another ionic liquid on its viscosity.
The EMS Viscometer is the ideal tool to perform such studies:
It requires only a small amount of sample to perform the measurements and can automatically measure the viscosity over a wide temperature range. Furthermore, the same sample can be used to perform measurements with different amounts of a certain additive or another ionic liquid added to check the influence of these additions on the sample's viscosity.
Liquids to Capture Carbon Dioxide
Liquids which are able to capture large amounts of carbon dioxide might help to reduce CO2 emissions in future. Often ionic liquids are considered for this application, as they have almost no vapour pressure and do therefore not evaporate even under high temperature. When developing ionic liquids for this application, it is important to know how the viscosity of the ionic liquid is influenced by the absorbed carbonic acid.
With the EMS Viscometer the corresponding measurements can be carried out quickly and accurately as its measuring cell can be pressurized.
Luminescent Materials
Luminophores are applied as thin emissive electroluminescent layers in display technology. To ensure a flawless application of a thin layer of the organic semiconductor, the viscosity of the material must exactly be known. The synthesis of new luminescent materials is normally complicate and expensive. To carry out several test normally only a minute amount of sample is available.
With the EMS Viscometer it is possible to determine the viscosity of luminescent materials with a very small amount of sample and there is no risk that the samples get contaminated during measurement. One sample can therefore be used for several tests without any problem.