Extended Material Characterization. ::: Intelligence in Rheometry

Transcription

1 Extended Material Characterization ::: Intelligence in Rheometry

2 Use your rheometer for Extended Material Characterization MCR rheometers offer you an open range of possibilities and this range does not stop at shear rheology. A comprehensive selection of easily integrated accessories transfer the capabilities of the intrinsically modular MCR series into other material characterization applications. Patented features ensure the convenient, reliable exchange and configuration of any application-specific accessory. The choice is yours: Whether you want to perform DMTA analysis in torsion or extension, interfacial rheology, tribology or more the dynamic performance, high sensitivity and low-torque capabilities of MCR rheometers are at your service.

3 4-5 Extensional rheology and mixing processes 7 Starch rheology 6 Dynamic Mechanical Thermal Analysis (DMTA) 9 Interfacial rheology 8 Large-particle rheology 10 Tribology

4 Use your rheometer for... Extensional rheology and mixing processes Sentmanat Extensional Rheometer (SER) The Extensional Rheometer System developed by Dr. Martin Sentmanat turns your MCR rheometer into a universal testing platform for extensional rheology. Combined with the convection temperature devices, this setup enables extensional tests, e.g. tests on synthetic polymers, biopolymers or tissues, across a wide temperature and deformation range. Beside characterizations in extension, the SER system can be used for solid tensile, tear, peel and friction testing. The setup consists of two drums which are connected to the rheometer. While one drum is driven directly by the shaft, the second is connected over gears and turns in the opposite direction. This setup can be immersed into a fluid to prevent potential sample sagging. The SER is completely integrated in the firmware and software of your MCR rheometer; the software provides all necessary extensional settings and presents all resulting properties requiring no further analysis. Used in combination with the SER system, the XIM Miniature Mixer attachment converts your rheometer into a miniature compounding, blending and mixing station that allows you to process batch sizes of less than 4 ml. Equipped with dual 2-wing and dual sigma-blade rotors, XIM is an ideal tool for mixing polymers, doughs and gelling systems. Specifications SER Extensional Rheology System Max. recommended 20 s -1 Hencky strain rate Max. Hencky strain 4 per drum revolution Operating temperature 0 C to 250 C Wind-up drum diameter mm Stretch zone gage length mm Accessories CTD 180/600/620, CTD 200/GL Specifications sample Min. shear viscosity in extension mode Pas Sample mass mg Recommended sample width mm Recommended sample thickness mm Visualization of an extensional experiment on a polyolefin melt XIM Miniature Mixer Lupolen 1840H measured at different Hencky strain rates compared to cone-plate measurements in oscillation

5 Use your rheometer for Extensional rheology Universal Extensional Fixture (UXF) The Universal Extensional Fixture (UXF) is used for tensile and extensional measurements on films and fibers. In combination with an MCR rheometer and a CTD convection temperature device, the UXF enables tensile strain- or stresscontrolled DMTA tests across a wide temperature range. This combined system is used to investigate effects such as temperature stability, shrinkage, elongation, crystallizations, phase transitions, relaxations and the brittleness of films and fibers. The modular system incorporates a rotating wind-up drum and an eccentrically positioned drum for fixing the sample; this setup allows DMTA tests in tension as well as uniaxial extensional measurements. The UXF s AntiSlip fixture ensures excellent grip between sample and drum even at maximum torques, while the convenient QuickSnap fixture allows quick single-hand adaptation and operation. The UXF is completely integrated in the firmware and software of your MCR rheometer; the application software provides all required extensional settings and presents all resulting properties without requiring further analysis. Specifications UXF Universal Extensional Fixture Multifunctional UXF Accessories Digital Eye QuickSnap TM, AntiSlip CTD 180/600/620, CTD200/GL CCD camera for visualization Temperature range -150 C to 270 C Temperature, control principle Temperature, safety features Convection, radiation, Peltier Actively cooled body and exhaust of CTD 600 and CTD 620 Creep, tensile stress mode (ATC) Adaptive Tensile Stress Control 1. Pull and twist to open Spring-based QuickSnap TM 2. QuickSnap TM to close Min. torque Rheometer software 0.01 μnm Supports all extensional variables Sample Toolmaster Wireless transmission of calibration data, name and dimensions of geometry Spring-based clamp lever The QuickSnap TM Fixture allows 'single-hand operation' of the UXF. MCR measuring system coupling Specifications sample QuickConnect Recommended sample width mm Drums: sandpaperlike surface Recommended sample thickness mm Length, sample 18 mm Sample Drum diameter 12 mm Spring-based clamp lever The AntiSlip fixture ensures an excellent grip at maximum torques. Max. extensional rate 5 s -1 Min. extensional rate 10-3 s -1 Recommended min. shear viscosity ~ Pas

6 Use your rheometer for... Dynamic Mechanical Thermal Analysis (DMTA) Fixtures for films, rectangular and circular solids MCR rheometers can also be used for Dynamic Mechanical Thermal Analysis (DMTA). The temperature and mechanical behavior of films, fibers and solids is investigated with a variety of available fixtures such as solid circular or rectangular fixtures (SCF, SRF), film and fiber fixtures (UXF) or parallel-plate systems. The large temperature range of the CTD convection temperature devices allow you to characterize materials from the glassy to the molten state. Consequently, materials transition temperatures and relaxations are precisely determined. All torsional and extensional data is recorded and presented in the MCRs' application software. The CTD 180, CTD 450 and CTD 620 equipped with the Digital Eye camera enable sample imaging or video recording directly in the software. A wide range of workbook templates is available, including analyses for the determination of transition points, curve slopes and more. Reaction kinetics can also be investigated, either isothermally or by presetting a temperature ramp and a defined heating rate. A special macro in the application software evaluates the degree of a material s cross-linkage and analyzes the sol-gel transition. Another application is Photo DMTA, which is used to investigate materials curing behavior initiated by UV light. Temperature sweep in torsion with glass transition Temperature sweep in extension with glass transitions UV cure and rate of cross-linkage

7 Use your rheometer for Starch rheology Starch Rheology System The Starch Rheology System turns your MCR rheometer into a platform for the analysis of starch gelling behavior at elevated pressure and temperature conditions. The high heating and cooling rates required for starch gelling measurements are achieved by combining electrical heating with fluid-circulator-supported cooling. A special stirrer prevents sedimentation in the liquid phase. The system can be used for starch tests under ambient pressure at up to 95 C and, equipped with a specific pressure cell (max. 30 bar), even allows rapid sample cooking up to 160 C. Any real process condition, such as food sterilization, can be simulated based on tailor-made test programs. Easily customized and automated workbook templates with pre-defined heating, holding and cooling intervals simplify your measurement setup and provide all required starch analysis results such as the gelation temperature, peak viscosity and final viscosity. The two examples below illustrate the Starch Rheology System s reproducibility for starch testing. Specifications Starch Rheology System Torque range 50 nnm to 200 mnm* Speed range 10-7 rpm to 3000 rpm Temperature range 0 C to 160 C Max. heating and cooling rates Pressure option 30 K/min Max. pressure 30 bar *depends on the rheometer model used Gelation of dent corn starch Gelation of modified waxy corn starch

8 Use your rheometer for... Large-particle rheology Building Material Cell The Building Material Cell (BMC) is specially designed for rheological measurements on building materials with large particles, providing information on processability, shelf life and flowability. Building materials are often pastes or highly filled suspensions containing large particles with sizes up to 5 mm. They show tendencies of wall slippage or separation when sheared with conventional measuring systems. The BMC's special vane and cup design eliminates this risk; its modular inset cages with flow breakers prevent wall slippage and improve mix-up effects. The Peltier-temperature-controlled cell is abrasion-proof and easy to clean, since all wetted surfaces are made of stainless steel. It is easily adapted to all MCR rheometer models and can be used in all rheological test modes: controlled shear rate (CSR), controlled shear stress (CSS) and oscillatory testing. Ball Measuring System The Ball Measuring System (BMS) is used in combination with an MCR rheometer to measure the flow properties of samples with very large particles. The system is based on a principle by Mueller-Tyrach which involves an excentrically rotating sphere. This sphere is available in various diameters depending on your samples viscosity. Due to the outstanding speed control of the MCR series EC motor, a full flow and viscosity curve can be determined in one single revolution of the measuring system. The flow properties of large-particle samples such as slurries, sludges or food products can be determined within one single rotation; dimensionless analysis of the produced flow field allows the online calculation of rheological parameters such as viscosity and shear rate. Flow curve of silica plaster measured with the BMC Amplitude sweep of silica plaster measured with the BMC

9 Use your rheometer for... Interfacial rheology Interfacial Rheology System The Interfacial Rheology System (IRS) combined with an MCR rheometer enables two-dimensional rheological measurements of interfacial films at the air/liquid and the liquid/liquid interface. In the IRS, a bi-cone measuring system is placed in the interface and measures absorbed or spread films, e.g. films produced by proteins or surfactants. Employing the low-torque capabilities and the TruStrain TM feature of the MCR rheometer, the IRS enables rheological measurements of weakest interfacial structures. The temperature is controlled by Peltier elements in the range from 5 C to 70 C; the patented normal force sensor in the air bearing of the MCR rheometer allows the accurate positioning of the bi-cone in the interface. A post-processing hydrodynamic flow field analysis subtracts the contribution of the bulk and covering phase and calculates the relevant interfacial properties of the measured interfacial layer. Specifications Interfacial Rheology System Measuring geometry Temperature 5 C to 70 C Accessory Bi-cone with radius of mm and bi-cone angle of 10 (2 x 5 ) P-PTD 200/80/I Measurements can be performed in rotational and oscillatory mode, e.g. allowing flow curves and creep tests at an interfacial layer or oscillatory tests during the film formation process. All measured and calculated interfacial data is recorded and displayed in the MCR series application software, in which pre-defined interfacial rheology workbooks are available for user-friendly operation. Software Specifications sample Spread interfacial film Absorbed interfacial film Covering phase Interfacial Flow Field Analysis Sample dissolved in solvent Sample dissolved in the bulk liquid Air or fluid Air/liquid interface Liquid/liquid interface

10 Use your rheometer for Tribology Tribology System The Tribology System (T-PTD 200) turns your MCR rheometer into a fully functional tribometer based on the ball-on-three-plates (ball-on-pyramide) principle. Side view The setup employs the fast, accurate normal force control as well as the excellent rotational speed and torque capabilities of the MCR rheometers for tribological measurements. Material wear tests can be performed as well as Stribeck curves, static friction tests and tailor-made measurements on lubricated systems. A special ball bearing option enables lubricant performance tests on rolling element bearings. The Tribology System developed together with Werner Stehr (Dr. Tillwich GmbH, Germany) consists of a sample plate fixture mounted on a specially designed spring system allowing threedimensional motion. This ensures concentric positioning and equal load on all contact points when a ball is pressed on the plates. This ball, the second friction partner, is mounted on a shaft and driven by the MCR rheometer s motor. This design enables the easy replacement and exchange of balls and plates to meet respective material requirements. Excellent temperature control in the range from -40 C up to 200 C is ensured due to the use of Peltier elements installed close to the plate holder and in an additional actively temperature-controlled hood covering the entire setup. Self-positioning plate fixture (movable in x-, y- and z-direction) Shaft Ball fixture Ball Plate The user-friendly application software enables flexible test programming in rotation and oscillation, displays all tribological parameters and includes pre-defined workbooks for Stribeck curves and static friction tests. Figure 2 illustrates friction tests between stainless steel balls and polyoxymethylene (POM) plates in dry and lubricated conditions. A constant load F N of 5 N per plate was set. The rotational speed was increased from to 1400 mm/s. The friction coefficient m is calculated as follows: m = F R /F N (F R : Friction Force, F N : Normal Load). Shaft Ball Top view Fig. 1: Setup of tribology geometry Specifications Tribology System Normal load range per plate Speed range Max. sliding speed v s Max. torque M Max. friction force F R per plate Ball diameter Rolling element bearing 0.3 N to 23 N 10-8 to 3000 rpm 1.41 m/s 200 mnm 19 N 12.7 mm (standard) 30 mm (optional) optional Fig. 2: Friction test steel/pom dry (blue) and lubricated (green)

11

12 Photos: Croce & Wir Anton Paar GmbH Anton-Paar-Str. 20 A-8054 Graz Austria - Europe Tel: +43 (0) Fax: +43 (0) info@anton-paar.com Web: Instruments for: Density & concentration measurement Rheometry Viscometry Sample preparation Microwave synthesis Colloid science X-ray structure analysis Refractometry Polarimetry High-precision temperature measurement Specifications subject to change without notice 02/13 C92IP007EN-C